The acidic water dissolves the carbonate rock along cracks and fractures in the bedrock dissolution within pore spaces and along fractures creates increasingly larger voids Download the NPS app to navigate the parks on the go Meeting scheduled at Savage River Lodge in Frostburg on March 13 The Maryland Department of Natural Resources (DNR) is scheduled to host an informational meeting on March 13 in Frostburg to take public feedback related to the potential Mid-Atlantic Resiliency Link (MARL) power transmission line project being planned by NextEra Energy that could stretch through Western Maryland The meeting will be an open house style setting to gather feedback from the public regarding impacts to wildlands There will be no formal presentations by the Department The discussion will take place from 4:30 p.m The meeting will be held in the main lodge DNR is hosting the meeting to better understand the community’s views about transmission lines and potential impacts on wildlands, forests, coldwater streams, and other natural resources. Residents who want to share feedback, but can’t attend the meeting, can do so through DNR’s online public comment form about the project As of publication, NextEra Energy is conducting a route study for the project and has not yet selected a route, according to its website The company plans to share route alternatives in the spring DNR will not know which specific public lands could be impacted by the project until specific route options have been identified by the company The project calls for building a new 105-mile 500-kV transmission line from Frederick County Pennsylvania to bolster the regional electric grid Maryland.gov The dates displayed for an article provide information on when various publication milestones were reached at the journal that has published the article activities on preceding journals at which the article was previously under consideration are not shown (for instance submission All content on this site: Copyright © 2025 Elsevier B.V. “The SMSU RN to BSN Program does not have you take a set amount of credits each semester This flexible scheduling was perfect for me as it allowed me to vary the amount of credits I took each semester I would have struggled without that flexibility as I am a non-traditional student who is also a wife and worked full time while completing my degree This program is designed to fit into your life whether you want to be a full-time or part-time student.” Thirty individuals have been selected to participate in Minnesota Agriculture and Rural Leadership (MARL) Class 13 The class members will begin their two-year leadership journey this fall with their first seminar on Sept MARL is a rigorous and dynamic two-year educational experience featuring 11 in-state seminars—six in the first year and five in the second year The program highlights include a national study seminar in Washington and an international study seminar to a destination to be determined by the MARL Board of Directors and announced in the summer of 2025 Class 13 is comprised of unique blend of individuals from agricultural producers and those involved in ag-adjacent “The board was incredibly impressed with the caliber of applicants for this class,” said Executive Director Brad Schloesser “We had forty-three highly qualified applicants which meant the board had the very difficult task of selecting only 30 of those applicants for MARL Class 13.” The following individuals have been selected for MARL Class 13: “We are excited for this class to begin as the participants represent communities and industries across the state,” Schloesser said “The MARL Program’s goal is to develop the leadership skills of those who are ready to make a difference in agriculture at the local The MARL seminar cycle is designed to accommodate the busy schedules of participants Most activities occur over the winter months The first seminar meets in the Bemidji/Itasca area on Sept MARL is a partnership between the Southwest Minnesota State University Foundation which serves as the administrative host and the University of Minnesota Extension which develops and delivers the curriculum The program is made possible by many generous investors and sponsors To learn more about the MARL Program visit www.MARLProgram.org SMSU's 57th Commencement Set for May 10 Read Article Student Association Election Results Announced Read Article SMSU's Seed Coalition Award Winners Announced Read Article The Owensboro Times April 10th at the West Kentucky Veterans Center in Hanson  He was born on September 11,1934 in Muhlenberg County to Ray and Lydia McIntosh and was a member and former elder of the Greenville Church of Christ He owned & operated McIntosh and Boggess Timber Company along with his cousin Clive Boggess for over 25 years cutting timber throughout the surrounding area from the late 1950s through 1986  He loved farming and was an avid quail hunter and woodworker  After retiring from the timber business he enjoyed playing golf with many friends and buddies at Twin Oaks in Greenville and the Central City Country Club April 15 at Gary’s Funeral Home in Greenville with Byron Groves and Paul Moore officiating  Friends are invited to call from 10:00 a.m   Burial will follow at the Memorial Gardens cemetery in Powderly The McIntosh family would like to extend a special note of thanks to the staff and caregivers at the West Kentucky Veterans Center in Hanson for the loving care provided over the past 9 months Privacy Policy Site by Tanner+West Center for Heritage and Archaeological Studies The future of White Marl is uncertain owing to proposed plans to widen a highway that bisects the site and Beier addressed potential measures that could be taken to mitigate or minimize adverse effects to this crucially important heritage site Heritage and Archaeological Studies Montclair State University Policies Return to Top Help keep local news alive—donate to support our community reporting!Donate Traci Husse candidate, election, housing, infrastructure, mayor, transparency Saline voters will see a familiar face running for mayor Brian Marl has led the city since 2012 and is seeking re-election for another mayoral term giving voters a chance to reflect on his leadership over the past decade he has focused on issues such as housing and economic development Marl shares his thoughts on these topics and others important to Saline residents Q: The council has recently discussed housing developments like apartments on Michigan Ave and a community on the property at the intersection of Saline-Ann Arbor and Waterworks high-end developments with the need for diverse options and attainable housing in Saline?   Brian Marl: I strongly support a policy of “smart growth” – thoughtful deliberate expansion of our housing and commercial amenities thereby growing and diversifying our tax base and enhancing our residents’ quality of life Expansion of our housing stock must include obtainable and affordable options While working with our state and regional partners we must incentivize projects that attract middle class families and those seeking to relocate to the Saline community Q: Citizens often attend council meetings to comment on agenda items but leave frustrated when they feel their comments did not impact the final vote Many participants are unaware that the most substantial discussions happen much earlier in the council’s process than the final meeting where a vote takes place How do you plan to enhance transparency and increase community participation in long-term decision-making processes particularly regarding the city’s projects I strongly encourage residents and business owners to attend subcommittee and board/ commission meetings when appropriate Many pertinent issues are evaluated and discussed at the board and commission level prior to being forwarded to City Council Participating in board meetings can often influence outcomes and feedback from residents is extremely beneficial as we make decisions on impactful local issues what core personal and professional values guide your vote and how do these values help you prioritize the needs of different community groups How will you demonstrate support for projects or measures that were approved even if/when you voted against them it starts with what is in the best interest of Saline residents “Our Shared Priorities.” These priorities included investment in our municipal infrastructure and openness/transparency in City government If these issues remain top priorities for our City as will our residents’ quality of life part of my job is to develop consensus with my colleagues and of course I try my very best to support the majority decision it is critically important to move forward and not rehash past issues once an outcome has been identified and a solution implemented.  Q: Small towns often have tight-knit communities How do you plan to serve constituents who hold vastly different views than you on core issues How do you plan to foster increased participation and more inclusive civic engagement especially among residents who (please respond to all three): Brian Marl: The Mayor of Saline must represent regardless of ideology or background – full stop I will continue to seek out and meet with individuals and groups who have been underrepresented and I will continue to make myself accessible to anyone in the community if they wish to meet or share ideas for the betterment of Saline I will also promote and continue to recruit a diverse array of individuals to serve in local government on our numerous boards and commissions.  such as a natural disaster or economic downturn community members seek guidance and advice from their local leadership Please share an experience where you led during a crisis or challenging situation and how that affected the outcome Brian Marl: I would cite an incident that occurred about five years back – a broken water main along US-12 subsequent issues with our main water tower this was a major inconvenience to our residents and business owners responded quickly and provided robust communication to all our utility customers in a news segment on local Detroit television while responding quickly and thoughtfully to resolve/mitigate the issue at hand.  Q: Residents have raised concerns about the city’s communication on important issues How do you plan to improve overall communications between the city and its residents and ensure that residents have real-time access to accurate and complete information from official sources Brian Marl: I actually believe we have the appropriate infrastructure and technology in place but must do a better job disseminating this information to the broader community Some examples – we have Documents-on-Demand email blasts to condo associations and HOAs The City also maintains a strong web and social media presence and staff is about to launch a new and vastly improved online reporting tool for local residents I believe it is more important than ever to engage directly and on occasion I will redouble my efforts to host/organize coffee hours and town halls for community members to interface directly with staff and other stakeholders while also discussing timely and relevant issues that are applicable to local residents and families.    his focus remains on continuing the work he has started Marl emphasized his commitment to open communication and thoughtful leadership as Saline navigates both opportunities and challenges he hopes to build on the progress made and continue fostering a strong Karen Lambert STN Staff The Sun Times News is the hub of the most useful information in Chelsea, Dexter, Milan, and Saline. Subscribe to our free daily newsletter to stay on top of all the local news. Volume 3 - 2015 | https://doi.org/10.3389/fevo.2015.00082 This article is part of the Research TopicUsing paleolimnology for management and restoration of lakesView all 12 articles Eutrophication is the most pressing threat to highly calcareous (marl) lakes in Europe Despite their unique chemistry and biology comprehensive studies into their unimpacted conditions and eutrophication responses are underrepresented in conservation literature A multi-indicator palaeolimnological study spanning ca 1260–2009 was undertaken at Cunswick Tarn (UK) in order to capture centennial timescales of impact Specific aims were to (1) establish temporal patterns of change (gradual/abrupt) across biological groups thereby testing theories of resistance of marl lake benthic communities to enrichment and (2) compare the core record of reference condition with prevailing descriptions of high ecological status revealed three abrupt changes in ecosystem structure with biomass increases in charophytes and other benthic nutrient-poor indicators supported ideas of resistance to eutrophication in Chara lakes occurred alongside reductions in macrophyte cover in support of ideas of threshold responses to enrichment Core P increased consistently into the 1990s when rapid transitions into pelagic shallow lake ecology occurred and Cunswick Tarn became biologically unidentifiable as a marl lake The moderate total P at which these changes occurred suggests high sensitivity of marl lakes to eutrophication the early record challenges ideas of correlation between ecological condition Management measures must focus on reducing external nutrient and sediment loads at early stages of impact in order to preserve marl lakes allowing for increasingly confident ecosystem reconstructions moderately clear water combined with dense aquatic flora is frequently considered near-pristine conditions yet may not reflect truly unimpacted ecology This may be especially true for marl lakes should further empirical support for sensitivity of their benthic communities arise In order to elaborate on concepts of marl lake ecology and -reference status a multi-indicator palaeolimnological approach was undertaken with specific aims to (1) establish the centennial-scale temporal patterns of change (gradual/abrupt) across biological groups (2) test whether ecological change was limited to one or two biological groups or whether it was apparent at an ecosystem level (physical–chemical function; multiple biological groups at all observed trophic levels; synchronicity across responses) and (3) compare the core record evidence of reference condition with prevailing descriptions of high ecological status for marl lakes assuming that marl lakes have distinct biological communities compared with other lake types both calcium (Ca) and P were expected to be significant correlates of biological community composition showing the core collection sites and water depths Two littoral sediment cores were taken from Cunswick Tarn (Figure 1). CUNS1 (74 cm) was taken in January 2008 at a depth of 2.4 m from the southwestern margins using a “fat” Livingstone piston corer (internal diameter 71 mm). CUNS2 (94 cm) was taken in October 2009 from the northern margins at a water depth of 4 m using a “Big Ben” piston corer (internal diameter 140 mm) (Patmore et al., 2014) Most palaeolimnological analyses were undertaken on CUNS2 but analysis of macrofossils and loss-on-ignition (LOI) in CUNS1 confirmed a lakewide signal and sediment samples for pigment analysis (CUNS2) were placed in separate bags and frozen Samples used to create the dating profile of CUNS2 in order to include these “ecophenotypes.” Uncalcified and calcified oospores were counted separately Chaoborus obscuripes and Chaoborus crystallinus were not separated and are referred to as C All data analysis was performed with R version 3.1.2 (R Development Core Team, 2010) using packages analogue (Simpson, 2007; Simpson and Oksanen, 2011), vegan (Oksanen et al., 2011), and mvpart (De'ath, 2002) Statistical analysis was only undertaken on CUNS2 data owing to the low resolution of the chronology for CUNS1 Diatom and testate amoeba data were transformed into percentage abundances and taxa with <5% abundance and less than five occurrences in the core profile were omitted Pigment and macrofossil data were (log10+1) and XRF data (logln)-transformed and normalized with respect to organic matter Cladoceran data were transformed into percentage data for principal curves and multivariate regression trees (MRT) and square-root transformed for all analyses pigment data were further standardized to abundances between 0 and 1 to reduce the statistical effects of “abundant” pigments (low degradation and to test for synchronicity in change across indicators (ecosystem change) Analysing each response separately allowed for a high number of data points and therefore confidence in grouping The number of data points was n = 94 (pigments) A previously developed cladoceran-based model capable of semi-quantitative inference of macrophyte and fish abundance, employing MRT (Davidson et al., 2010a) was also applied to the cladoceran data set (n = 32) in order to estimate past plant abundance [late summer plant volume infestation (PVI); Davidson et al., 2010b] ephippia (counted only at macrofossil resolution) for missing levels was modeled based on the relationship between ephippia (macrofossils) and post-abdominal claws (cladocerans) and biological data sets were tested using redundancy analysis (RDA) Owing to the varying resolution of the data Analysis of the diatom data set was omitted due to the low number of matching observations To allow for temporal ordering of the data significance of variance explained was tested using ANOVA with cyclic permutations The lowest attainable p-value of such permutations depends on the number of observations tested (1/n) and therefore significance was unattainable for most data sets at a 0.05 level (e.g. permutation tests were also performed without restrictions Core CUNS2 spanned a period of approximately 1260–2009 AD (date of core collection) with highest age uncertainties in the middle section of the core (46.5–75.5 cm; Figure 2). The gap in measured ages was unavoidable given the constraints of the time spans of 210Pb (to ca. 150 years from present) and radiocarbon dating (minimum age several hundreds of years). Sedimentation rates (SRs), core carbonate (Figure 3) 1 in Supplementary Material) followed a similar pattern the latter two of which were considered equivalent owing to deposition as calcite/marl (CaCO3) and their high correlation (Spearman's rho = 0.97 Figure 3. Carbonate concentrations in cores CUNS1 and CUNS2, shown with calendar years obtained by 210Pb-dating of CUNS2 with errors (±), and approximate calendar years based on radiocarbon dates (see Table 1 for details) Four carbonate zones were apparent in CUNS2 (Figure 3) and were used as Zones for all Diagrams in Supplementary Materials and as sections for presentation of biological data results Zone 1 encompassed the base of the core (92.5 cm; 1250s) to the early 1400s characterized by relatively low carbonate content (<10%) Carbonate and SR were at their lowest values in Zone 2 (ca which encompassed the 1400s (72.5 cm) to the 1890s (42.5 cm) Zone 3 (42.5–22.5 cm) encompassed substantial increases in carbonate and SR (to ca with two carbonate peaks of 36% and 40% (1920s) followed by a rapid decline (ca 0.2–0.5 cm year−1) occurred in Zone 4 from the 1930s (22.5 cm) to 2009 (core top) Higher carbonate concentrations than in CUNS2 were found in Zone 2 (ca and similar carbonate peaks (>40%) occurred in Zone 3 CUNS2 carbonate δ18O could not be measured for most of Zone 2 owing to insufficient carbonate (data not shown). Therefore, only 14 samples were analyzed, five of which were in Zones 1 and 2 and had highly variable δ18O out of equilibrium with rainfall (−3 to −6‰), indicating a hydrologically closed system (Leng and Marshall, 2004; Leng et al., 2006) The uppermost nine samples ranged between −6 and −7‰ and were in equilibrium with rainfall indicating that Cunswick Tarn became a hydrologically open system between the 1890s and 1900 CUNS2 P concentrations were expressed relative to core organic matter to correct for dilution by calcite and are therefore only interpretable as relative values within the core sequence (Supp the lowest concentrations occurred before the 1530s (0.5–0.6) and between the 1530s and the 1890s (0.4–0.45) Rapid increases occurred in the early 1900s coincident with increases in Ca concentrations increased consistently from 0.7 to 1 (Supp and cyanobacteria were low in Zone 1 (Supp slightly higher concentrations of diatom (diatoxanthin) and cryptophyte (alloxanthin) pigments occurred throughout The notable difference between the zones was the concentration of a purple sulfur bacterial pigment (okenone) which was highest at the base of the core and declined to levels below detection at the upper limit of Zone 1 (Supp Remains of pelagic cladocerans at the base of the core were relatively abundant and declined slightly toward the upper end of the zone (e.g. Other filter-feeding and/or pelagic species included D Plant- and mud-associated species included Alonella exigua Species exclusive to Zone 1 included Pleuroxus truncatus Plant macrofossils included terrestrial Juncus spp and uncalcified oospores of Chara hispida agg. statoblasts were particularly abundant in Zone 1 compared to the rest of the core (Supp Mollusca were largely absent with the exception of Sphaeriidae and key absolute and relative abundance changes of biological groups against time Changes among the dominant testate amoeba taxa (Supp 3 in Supplementary Material) included gradual increases in Cucurbitella tricuspis (to ca before rapidly declining in the mid nineteenth century and decreases in Difflugia oblonga “oblonga.” Centropyxis constricta “aerophila” and Arcella vulgaris increased in abundance while Cyclopyxis kahli remained in lesser proportions Diversity and total abundance of cladocerans were at their lowest in Zone 2, and pelagic taxa were rare (Supp. 4 in Supplementary Material, Figure 4). The community was dominated by benthic taxa (e.g., Tremel et al., 2000; Thienpont et al., 2015) including Chydorus sphaericus ephippia were abundant (n >1000 × 100 ml−1) at the beginning of Zone 2 (ca followed by consistent decreases to the upper end of the zone (n < 100 × 100 ml−1) the Sphaeriidae dominated the record (maximum of n = 50–100 × 100 ml−1) whereas in CUNS1 several different taxa became more abundant toward the latter part of the Zone (Bithynia leachi/tentaculata Cladoceran abundances were highest in Zone 3 (Figure 4) however community composition changed toward a dominance of strictly plant-associated species: Pleuroxus laevis and A Ephippia of pelagic cladoceran taxa were largely absent or rare in CUNS1 and CUNS2 (Supps increased consistently from the 1930s to the 2000s in the macrofossil (CUNS1 CUNS2) and cladoceran records (CUNS2) (Supps which had been absent from the record after the 1400s Five plant-associated cladoceran species characteristic of Zone 3 declined in abundance in contrast to increases in ubiquitous species (Alonella nana) filter feeders (Sida crystallina) and sediment-associated species (Leydigia leydigi) (Supp The abundance of mollusc remains decreased markedly following the 1940s and Bithynia spp became the dominant taxon until the 1980s after which numbers declined to Zone 2 levels (Supps 6 negatively influenced the strength of the test with Ca RDA-based correlations and p-value of Ca and P over biological data Chronological MRT splits are indicated as the midpoint between samples either side of a split and therefore are not an exact reflection of the temporal relationship across groups While P and Ca data occurred at identical depths the splits for pigments (median age gap 6 years) will necessarily be more precise than those for macrofossils (median age gap 40 years) In order to remain unambiguous about split locations given the exact dates put into the model dating errors were not incorporated into split estimates Four significant MRT zones were identified for P (Figure 5). For Ca, three or four significant zones were identified by MRT depending on the data transformation used (bimodality in the density distribution of Ca-values interfered with the method). In order to cohere with P and biological data groupings, and to delineate the decline in Ca content in the uppermost section of the core (Figure 3) Relatively small changes occurred in P and Ca concentrations between 1200s and the late 1800s within which one split was found at ca Changes were more synchronous in the latter end of the sequence where splits were identified at 1896 (Ca) The first split marks an increase in the concentration of both elements and the second a decrease in Ca and continued increase in P Horizontal lines indicate MRT-derived splits those dashed to aid inspection indicate least importance Principal curves identified modest changes in biological communities between the 1200s and the late 1800s. MRTs located shifts of cladocerans and pigments around 1427, and 1370 and 1458, respectively, followed by macrofossils around 1500, and testate amoebae around 1516 (Figure 5) Substantial community change occurred between the 1890s and the 2000s during which splits in biological groups showed clear synchronicity Split 2 as per P (1902) and Ca (1896) (Zone 2/3) cladocerans (1898) and macrofossils (1901) where Ca declined (1930) (Zone 3/4) and P continued to increase (1935) coincided with splits in pigments (1936) The highest number of significant splits occurred in primary producers (pigments n = 8, diatoms n = 5), which also changed significantly in the most recent years (pigments: 2000, diatoms: 1995), coincident with the most recent split in cladocerans (1990) (Figure 5). The highest frequency of splits occurred between the 1900s and 1930s. The most important pigment splits are indicated by solid lines (Figure 5) Primary producer and cladoceran community changes were therefore assumed to be independent of top-down effects from fish Cladoceran-inferred August plant volume infestation and zooplanktivorous fish abundance of CUNS2 sample depths (cm) the former is a previously undocumented eutrophication-driven switch in marl deposition with important consequences to lake management targets and marl lake reference conditions which may confound simplistic responses to nutrients Shallowing is supported in the oospore record of CUNS2 by a shift from a dominance of the Chara hispida group to the more shore-line associated, lower-growing Chara aspera. However, evidence for a predominant effect of eutrophication following an initial pulse of lake shallowing is supported by a few factors. Firstly, the Ca and oospore increase also occurred in CUNS1, the location of which was 1.5 m shallower than that of CUNS2 (Figure 1) CUNS1 reflected littoral conditions (high carbonate content and Chara aspera oospores) throughout the record and therefore did not undergo charophyte community shifts suggesting that increased nutrient availability was in part responsible for the change the change in Ca and charophytes was a continuous rather than a stepwise transition suggesting underlying eutrophication responses independent of a simple water level change the positive relationship between Ca and P in the early 1900s strongly suggest a eutrophication effect on Chara biomass and marl deposition Rate of change in P and ecological distances between consecutive samples of biological groups suggesting that high charophyte densities were the main factor in maintaining clear water and ecology reflective of nutrient-poor conditions and increasing N availability could be contributing to the 1920s shift in community composition toward a difflugid-dominated assemblage The transition in algal and testate amoeba indicators corresponded with shifts toward angiosperm dominance and reduced macrophyte biomass in the lake which may indicate a combined effect of nitrogen and phosphorus in shaping the biological eutrophication responses of Cunswick Tarn and the low concentration of Nymphaeaceae trichosclereids It remains possible that (1) climate effects were non-linear and (2) climatic conditions interacted with more discrete change within the catchment over the period between zones 1 and 2 there are unfortunately no detailed records to support the hypothesis Some support for shading and DOC as drivers of ecological change can be found in the more recent history of the lake during which okenone has reappeared in the core record The period coincides with growth of willows (Salix spp.) at the lake margins bank erosion at the north end of the lake which has resulted in high DOC and suspended sediment loads and strong chemical stratification with hypolimnetic anoxia in summer months hence being required to achieve both Good ecological status and Favorable conservation status Sites with such dual designation are additionally considered “protected areas” under WFD and are consequently given earlier deadlines for achieving their target objectives with Cunswick Tarn data in particular indicating shifting perceptions of good ecological status this improved understanding of the pre-impact character of Cunswick Tarn has implications for how it is described protected and restored under national nature conservation designations (SSSI); the Tarn is currently identified as a naturally eutrophic water body which is in strong disagreement with the palaeolimnological data and foodwebs based on benthic production with planktonic taxa largely absent and historical communities based on available historical data Near-pristine conditions in Cunswick Tarn were therefore remarkably “non-marly.” which was also indicated in the early record of Cunswick Tarn Cunswick Tarn is currently a marl lake only by geology, and is therefore considerably impacted. It is highly unlikely that conditions similar to the thirteenth to eighteenth centuries can be attained given the high load of P in the sediment, low flushing rates, and therefore high potential for internal loading in the lake. However, reductions of external nutrient loads are potentially the most effective means of restoring shallow lakes (Jeppesen et al., 2007) especially lakes such as Cunswick Tarn where fish manipulation is irrelevant Unless nutrient availability for phytoplankton is restricted charophytes will not be able to recolonize the Tarn The most likely sources of nutrients to the Tarn are in the north where a drain pipe leads directly into the lake and high nutrient concentrations have been measured in the inflow (December TP 44 μg L−1) Streams in the east woodland are likely to contribute less (December TP 14–20 μg L−1) the feeding of artificially high populations of ducks in the lake margins was a further major nutrient source Given the potential for hydrology to be complex in limestone catchments an inclusive and larger scale approach to determining nutrient sources may be important coppicing around the lake would be strongly advisable Biological community shifts in Cunswick Tarn demonstrated synchronicity in response to gradual eutrophication pressure Drainage of the lake and land improvement in the lake surrounds in the 1890s led to sub-decadal responses in multiple biological groups (microalgae cladocerans) and substantial increases in carbonate precipitation Further abrupt ecosystem shifts occurred in the 1920s and finally the 1990s when the lake changed into its current condition of low macrophyte diversity reduced macrophyte colonization depth and predominance of nutrient-tolerant micro- and macrophyte taxa The patterns of rapid ecosystem-wide change partly decoupled from the change in core P supported ideas of abrupt responses to eutrophication as well as the importance of internal dynamics such as the self-sustaining capacity of charophyte beds Variance in marl lake biological communities correlated with both Ca and P as expected for marl lake communities responding to external nutrient load the period of least impact in the Tarn was characterized by very low carbonate precipitation in the deeper water with marling restricted to the shallower littoral zone where charophyte meadows occurred It is likely that pristine marl lakes do not attain sufficient levels of photosynthesis for intensive whole-lake scale authigenic carbonate precipitation and that macrophyte cover could be quite low The detection of two periods of accelerated change over intermediate core P concentrations support hypotheses of high eutrophication sensitivity of benthic communities in marl lakes especially considering the modest concentration of TP (ca 56 μg L−1) in Cunswick Tarn currently the association of high benthic biomass and calcite deposition with high ecological condition may be biased reflecting a shift in perception due to the scarcity of truly high quality examples of marl lakes The complete loss of marl lake biology in Cunswick Tarn argues strongly for restoration interventions at early stages of eutrophication in order to preserve characteristic marl lake communities if similar lake type transformations have occurred in other (formerly) marl lakes perceptions of their geographical distribution and scarcity may be misguided The majority of this publication is the direct result of a PhD by EW EW undertook all palaeolimnological analyses excepting testate amoebae which are part of a PhD by SP and diatoms which were part of an undergraduate dissertation by LS All fieldwork was undertaken by EW and a combination of HB GS offered crucial guidance during statistical analysis of the data during EW's PhD and also contributed to the design and execution of statistical methods particular to this publication and all other authors contributed essentially to the interpretation and wording of components falling within their expertise The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest This study was funded by a NERC and Natural England Ph.D Funding of sediment isotope analyses was awarded to EW by the NERC Isotope Geosciences Facilities (IP-1220-1110) (stable isotopes) and the NERC Radiocarbon Facility (NRCF010001; 1685.0313) (radiocarbon dating) with the help of Dr Charlotte Bryant at the NERC labs for her commitment many thanks go to the gamekeeper Andy Dixon for providing access to Cunswick Tarn to field experts Ian Patmore and Jorge Salgado for crucial help with coring and equipment maintenance Thanks also to John Birks and staff at various Natural England offices for finding and sharing old survey data of the site and to John Boyle for his expert advice on interpreting XRF data Thanks also to Teresa Needham and Graham Morris (University of Nottingham) for assistance with pigment analysis Miles Irving and Cath D'Alton at the UCL Drawing Office constructed macrophyte colonization and site location diagrams thanks to Magdalena Toporowska for introductions to Polish marl lake literature and the reviewers for their constructive and positive suggestions for manuscript improvement The Supplementary Material for this article can be found online at: http://journal.frontiersin.org/article/10.3389/fevo.2015.00082 The culicidae of sardinia and corsica (diptera) CrossRef Full Text | Google Scholar Equilibrium and disequilibrium stable isotope effects in modern charophyte calcites: implications for palaeoenvironmental studies “Chronostratigraphic techniques in recent sediments,” in Tracking Environmental Change Using Lake Sediments Last (Dordrecht: Kluwer Academic Publishers) Google Scholar 210Pb dating by low background gamma counting CrossRef Full Text | Google Scholar Palaeolimnology as a tool to inform shallow lake management: an example from Upton Great Broad Seventy years of changes in the abundance of Danish charophytes CrossRef Full Text | Google Scholar “Diatoms,” in Tracking Environmental Change Using Lake Sediments Google Scholar A palaeolimnological meta-database for assessing the ecological status of lakes Defining reference conditions and restoration targets for lake ecosystems using palaeolimnology: a synthesis Harnessing the potential of the multi-indicator palaeoecological approach: an assessment of the nature and causes of ecological change in a eutrophic shallow lake 15 years of pond assessment in Britain: results and lessons learned from the work of pond conservation Blaauw, M., and Christen, J. 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This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) distribution or reproduction in other forums is permitted provided the original author(s) or licensor are credited and that the original publication in this journal is cited in accordance with accepted academic practice distribution or reproduction is permitted which does not comply with these terms *Correspondence: Emma Wiik, Department of Biology, University of Regina, Laboratory Building, 3737 Wascana Parkway, Regina, SK S4S0A2, Canada,ZW1tYS53aWlrQHVyZWdpbmEuY2E= Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher 94% of researchers rate our articles as excellent or goodLearn more about the work of our research integrity team to safeguard the quality of each article we publish The landscapes we see today in Everglades National Park are the direct result of geologic events of the past and ongoing environmental processes Although the activities of humans have altered the south Florida landscape The geologic secrets of the earth are visible to all who learn to recognize them It is impossible to consider the geology of the Everglades without also considering the hydrology the bedrock geology of Everglades National Park has responded over time to the ongoing processes of weathering and episodes of sea-level rise and fall to produce the landscapes we see today nearly flat seabed that was submerged at the end of the last Ice Age Its limestone substrate is one of the most active areas of modern carbonate sedimentation UNESCO recognized that the subtropical wetlands and complex biological processes that make the Everglades a sanctuary for its legendary wildlife would not exist were it not for the underlying geology which predefines existing Everglades landscapes and ecosystems subtle changes in elevation result in dramatic changes in vegetation communities Pine forests are present on the higher ground of the Atlantic Coastal Ridge Sawgrass prairies extend south of the ridge A narrow band of mangroves fringes the southeastern coast and the shallow waters of Florida Bay provide an abundant food supply for great numbers of wading birds South Florida lies within the Atlantic Coastal Plain physiographic province this province is divided into seven subprovinces: Okeechobee Basin Johns River Water Management District;Map courtesy of Trista L water flowing through the Greater Everglades slowly trickled south down to the sea from the Okeechobee Basin subprovince in central Florida freshwater overflowed the south shore of Lake Okeechobee and flowed about 100 miles dropping only about 12 to 14 feet in elevation to reach its southern terminus in Florida Bay human population has steadily increased in south Florida and levees were built to drain swamps for agriculture built from the spoils of canal construction slow moving sheetflow of water from Lake Okeechobee to Florida Bay people have forever altered the once-steady slow flow of freshwater through the Everglades also known as the "River of Grass." The Everglades subprovince forms an elongate low-lying area between the Southern Atlantic Coastal Strip subprovince to the east and the Big Cypress Swamp subprovince to the west The elevation change is only 12 to 14 feet from the maximum near Lake Okeechobee to sea level Prior to the digging of canals and building of dams flow in this drainage system was slow and steady from north to south Karst is a term used for the characteristic terrain produced by the chemical erosion of carbonate rocks such as limestone and dolomite Acidic water dissolves the carbonate rock along cracks and fractures in the bedrock Most precipitation is of relatively neutral pH but becomes increasingly acidic as it infiltrates live plant tissue The extensive carbonate rocks of Florida are inherently porous and have been exposed to weathering processes since the last significant interglacial period led to widespread flooding about 130,000 years ago much of the original bedrock has been altered and partially dissolved by acidic rain and groundwater The Rocky Glades region of Everglades National Park is an area of karst that separates Shark River Slough from Taylor Slough Solution holes are pits in karst that formed in the past when sea level and the water table were lower than present levels Solution holes provide winter dry-season refuge for aquatic animals and provide a repopulation source for species upon reflooding of the marsh during the following summer wet season Caused by weak acids created by decaying vegetation dissolving the limestone bedrock which is at or inches below ground level    Form when the ceiling of an underground cavity suddenly collapses  Caused by clay soils seeping into and eroding away the underlying limestone bedrock which is found deeper below ground level than in southern Florida organic material in the periphyton oxidizes leaving calcium carbonate behind as light-colored soil Marl also is called calcitic mud and it is common in the short-hydroperiod (short-term flooding) wet prairies of Everglades National Park Marl is the most common soil seen on the drive to Flamingo along the main park road Peat soil is a product of long-hydroperiod (long-term flooding) wetlands and typically occurs in areas of deeper bedrock Peat is composed of the organic remains of dead plants The color of peat depends on its plant source Peat derived from sawgrass is typically dark brown to black in color hot fires that burn during the winter dry season Accumulation of peat requires anaerobic conditions microorganisms cannot decompose plant material as fast as it accumulates Abundant precipitation in south Florida during the summer rainy season causes flooding of vast low-lying areas which prevents oxygen in the air from touching soils and allows the organic material to transform into peat If left undisturbed over long periods of time increasingly thick layers of peat accumulate until the surface is able to dry sufficiently to allow either decay or fire Most natural fires that burn in the Everglades occur during the spring typically coinciding with the end of the winter dry season when water levels are at their lowest and average daily temperatures are quickly rising human interference in the ecosystem in the form of water-management practices has drained large parts of the Everglades and resulted in severe losses of peat in some areas Marl and peat soils are like opposites that cannot coexist Peat does not accumulate in the short-hydroperiod marshes in which marl accumulates and the acidic conditions in which a peat soil thrives would dissolve marl The Big Cypress Swamp subprovince defines the western boundary of the Everglades subprovince The rocks underlying Big Cypress Swamp are among the oldest in south Florida and are composed of silt This area is slightly higher in elevation that the Everglades basin because it is underlain primarily by the coral-rich limestones of the Pliocene (3 to 5 million years ago) Tamiami Formation which is exposed in large areas of Big Cypress National Preserve Elevation in Big Cypress Swamp ranges from 12 to 39 feet above mean sea level in the northern reaches to just slightly above sea level in the mangrove areas in the south Drainage in the province is primarily to the south and southwest Southern Atlantic Coastal Strip Subprovince The Southern Atlantic Coastal Strip subprovince consists of Pleistocene (Ice Age) Miami Limestone a marine limestone covered by thin sheets of quartz sand This limestone is composed of tiny spheres called ooids Calcium carbonate settling out of the seawater coated tiny bits of shell and sand in layer upon layer were pushed by longshore currents into the linear Atlantic Coastal Ridge during the Pleistocene The ooids later cemented into the rock formation known as Miami Limestone (formerly known as Miami Oolite) and this same limestone also covers much of the area to the east of Everglades National Park and most of Florida Bay the oolitic Miami Limestone grades into a marine limestone composed of the calcified carbonate remains of tiny moss animals called bryozoans which lived in quieter waters in the area that is now the central part of Everglades National Park The Atlantic Coastal Ridge extends from Mahogany Hammock northeast to Miami and ranges in elevation from 5 to 20 feet in the southernmost parts The width of the ridge ranges from about 10 miles in southern Miami-Dade County to 3 to 5 miles farther north The ridge prevents water in the Everglades from flowing east and draining into the Atlantic Ocean directing it instead toward the southwest and into Florida Bay Much of the south Florida metropolitan area has been built along the Atlantic Coastal Ridge much of this landscape has changed dramatically as a result of urban growth The southern parts of the Atlantic Coastal Ridge are breached in places by sloughs (marshy channels of water) oriented perpendicular to the trend of the ridge The southernmost part of the Southern Atlantic Coastal Strip subprovince wraps around the southern end of peninsular Florida and contains vast tracts of coastal marshes and mangrove swamps These wetlands cover the area extending from the northeastern part of Florida Bay and west into the Gulf of America as far as the Ten Thousand Island region near Everglades City Strips of swamps and brackish marshes that are just above sea level characterize this area Freshwater runoff and tidal fluxes cause the salinity to vary dramatically and lagoons characterizes the Ten Thousand Islands subprovince which extends for about 60 miles along the southwestern edge of the Big Cypress Swamp and Everglades subprovinces on Florida's Gulf Coast The complex of small islands that make up the Ten Thousand Islands protects inland areas from the destructive and powerful winds and flooding caused by tropical storms and hurricanes that rampage from time to time in the Gulf of America These uninhabited islands are surrounded by a highly productive estuary where freshwater draining from the land mixes with saltwater from the Gulf of America The mangrove islands provide protected habitat and nursery areas for many terrestrial and marine animal species and branches eventually fall into the water where they decay and decompose into organic detritis which forms the basis of an elaborate food chain The nutrient-rich soup supports a robust marine nursery for species such as pink shrimp The Ten Thousand Islands subprovince is largely the result of multiple sea-level fluctuations during the Ice Age Although glacial ice never extended as far south as Florida the effects of distant glaciation are evident The resulting global-scale climatic and sea-level changes played a major role in the formation of the geologic formations and the overall landscapes that we see today in south Florida Copious amounts of freshwater were trapped within the glaciers as the size of the massive continental ice sheets increased sea level in south Florida lowered as much as 300 feet below present levels The Great Ice Age actually consists of four shorter and smaller ice ages with periods of warming in between returning large amounts of fresh meltwater to the sea The last interglacial stage occurred about 100,000 years ago sea level in south Florida rose about 100 feet above present levels sea-level fluctuations resulted in constantly changing conditions during which periods of sediment deposition alternated with periods of erosion The variable layering of rocks and sediments that tells the story of Florida's sedimentary history is the result of these variations in sea level Composed of limestone or carbonate sand and mud the Florida Keys subprovince consists of long narrow islands that stretch in an arc from the northernmost keys of Biscayne National Park to the southwesternmost keys of remote Dry Tortugas National Park upper keys are the exposed remnants of coral reefs that fossilized and were exposed as sea level declined North of Elliott Key in Biscayne National Park lie several small transitional keys that are composed of sand built up around areas of exposed ancient coral reefs Yet further north in the Miami metropolitan area as are the barrier islands that protect much of the entire east coast of Florida consist of oolitic limestone that is similar to the bedrock that makes up the previously discussed Atlantic Coastal Ridge The shallow waters of Florida Bay are separated into many smaller basins by shallow banks and small islands the lower keys consist of carbonate sands and muds that consist of the remains of small marine plants and animals Drastic fluctuations in sea level resulting from the Ice Age further shaped the Florida Keys into the landscape we see today several parallel reefs formed along the edge of the submerged coastline Later sea-level fluctuations caused some of the Miami Limestone to dissolve and then redeposit as a denser cap rock overlying the Key Largo and Miami limestones Rounding out the physiographic subprovinces that make up south Florida are the Miocene (5 to 23 million years ago) and Pliocene (3 to 5 million years ago) sedimentary rocks and sediments that underlie the Southwestern Flatwoods subprovince which lies to the northwest of the Everglades subprovince and west of the Okeechobee Basin subprovince Landforms in this subprovince include flatwoods Also present in the northwestern corner of Everglades National Park the wedge-shaped Tamiami Formation crops out at land surface in the lower reaches of Big Cypress National Preserve and appears as far north as Fort Lauderdale on the east coast of Florida Following deposition of the sediments of the Tamiami Formation in a warm rising sea levels eroded and dissolved the uppermost layers and a subsequent decline in sea levels resulted in deposition of the Miami Limestone on top of the Tamiami Formation The highly permeable calcareous sandstones and sandy limestones that make up the Tamiami Formation are layered with impermeable clay-rich layers that cannot transport large amounts of groundwater Commonly found fossils in the Tamiami Formation include barnacles Doug Marrin Saline Police Department updates, Saline public safety, Saline traffic enforcement, Saline Wellness Initiative Saline Mayor Brian Marl delivered his 13th annual State of the City address at my first ever State of the City address as Saline Mayor I expressed the belief that the path of least resistance is always downhill,” opened Marl “That Saline’s way was that of the rising road I indicated our City remained committed to tackling big issues not ignoring problems or coasting through times of prosperity.” Economic Development: A Pro-Business Stance Mayor Marl reaffirmed Saline’s commitment to supporting local businesses and attracting new ventures emphasizing the city’s focus on partnerships and strategic initiatives “Saline will never have the ignominious distinction of being hostile to business or private sector investment,” he declared Ongoing efforts include creating a comprehensive business database and evaluating a community greenspace project Marl noted progress on mixed-use developments at 1080 East Michigan Avenue and 147 West Michigan Avenue Infrastructure Investment: Building for the Future The Mayor detailed Saline’s robust infrastructure investments but it certainly bears repeating – based on our strong track-record over the past several years it should be crystal clear to all residents and business owners – the days of infrastructure delays and deferrals are over.” Highlights included the ongoing Wastewater Treatment Plant rehabilitation the upcoming Saline River Valley Trail project and continued lead service line verifications “We remain committed to public engagement on this issue and welcome feedback/concerns from community residents.” He encouraged residents to email their opinions to City Engineer Tesha Humphriss by January 31st Residents are encouraged to follow updates on all projects via the ClearGov website Fiscal Responsibility: Growth with Prudence Mayor Marl celebrated the city’s sound financial management sharing that the overall net position grew by 19.35% in the past fiscal year He attributed this to increased property values and strategic revisions in investment policies “The City of Saline has fully embraced a philosophy of reinvestment in infrastructure to enhance public services and improve our residents’ quality of life,” he stated “We are prudently funding post-employment benefits Saline is well-positioned to meet our future demands which is bolstered by the appropriate policies has allowed us access to lower borrowing costs for our critical municipal needs The City’s total debt remains well within state-imposed limits – in fact we have capacity for an additional $47.5 million in allowable debt.” The City recently received its annual audit for fiscal year 2024 it received a perfect opinion from the auditing firm Mayor Marl confirmed staffing improvements within the Saline Police Department and announced upcoming traffic enforcement near schools to address congestion He also highlighted the Saline Area Fire Department’s strategic planning efforts and the city’s launch of a new Wellness Initiative aimed at addressing mental health “Our first responders can rest easy knowing that our community’s elected officials will continue to provide them the resources they need,” he assured The mayor also reflected on a tragic incident on December 29 when a serious event occurred at City Hall involving the Saline Police Department Marl commended the swift and professional response of SPD officers whose coordination was critical in resolving the situation He emphasized the need for greater mental health awareness and expanded healthcare services underscoring the city’s commitment to launching a new Wellness Initiative to address mental health Marl highlighted significant progress made by the Saline Area Fire Department (SAFD) over the past year including the development of a capital improvement plan The city has also approved a request for proposals (RFP) to evaluate fire services a routine action aimed at identifying potential cost savings and operational improvements nor does said action deviate from the established protocols of the past decade,” assured th Mayor “We’ve conducted independent reviews/evaluations of police services while also completing both a municipal wage study and organizational review aligns with the city’s broader goal of ensuring public safety and organizational efficiency Mayor Marl reiterated the city’s dedication to supporting emergency services acknowledging the critical role of first responders and committing to providing the resources necessary for their success Transparency and Community Engagement: A Culture of Positivity Mayor Marl underscored the city’s dedication to open communication and operational efficiency our best days are yet to come,” he concluded urging residents to engage with the city’s resources and contribute to its ongoing success The Mayor closed by thanking city staff and council members for their service reiterating his optimism for Saline’s future; “Let us not be distracted by personalities or any petty grievances Volume 10 - 2022 | https://doi.org/10.3389/feart.2022.1075151 This article is part of the Research TopicRock Physics of Unconventional ReservoirsView all 11 articles Eagle Ford Formation has significant heterogeneity due to the existence of marl and interbedded limestone layers The objective of this paper is to study the elastic properties of different layers in the Eagle Ford Formation the relationships between compressional and shear velocities in marl and limestone layers were investigated in two representative Eagle Ford wells These empirical equations can be used to estimate the shear velocity in Eagle Ford wells without sufficient well log data correlations between elastic properties and GR were obtained Among all layers in the Eagle Ford Formation marl layers of the lower Eagle Ford have the lowest averaged values of compressional velocity shear velocity and dynamic Young’s modulus while the limestone layers of the upper Eagle Ford have the highest averaged values of these three elastic parameters the effect of elastic properties of shale layers on the aspect ratio of unconfined and confined fractures were evaluated The influence of Young’s modulus contrast of shale layers on the aspect ratio of confined fractures was remarkable In the unconventional reservoir stimulation hydraulic fracturing design is usually performed in layered shales which are stratified by layers with distinct mechanical properties Elastic parameters are crucial to seismic imaging wellbore stability and hydraulic fracturing treatment The elastic parameters including compressional velocity and minimum horizontal stress can be obtained from mechanical well logs the high expense of the mechanical well logging limits the usage of well logs it is time and cost efficient to estimate elastic properties from conventional well logs The compressional and shear velocities of synthetic shale samples were measured Results showed that sonic velocities were negatively related to TOC and clay content Although previous researchers have investigated the elastic properties of the Eagle Ford Formation (Hsu and Nelson, 2002; Yang et al., 2019; Kim, 2021) most of the results focused on the average values of reservoir properties over a certain depth interval or on presentative shale samples Little research has been done on the characterization and quantification of the elastic properties in marl and interbedded limestone layers the correlations of velocities as well as correlations of elastic properties and gamma ray or clay content in marl and limestone layers of the Eagle Ford Formation will be developed respectively the effect of elastic moduli on fracture aperture of layered shale is discussed in this study The well in this study is on the southwest side of the San Marcos arch and is close to the Edwards Reef Margin and the Sligo Reef Margin. It is in the jointed zone of the gas condensate and dry gas zone. Vertically, the Eagle Ford Formation can be divided into the Upper and Lower Eagle Ford based on previous research (Donovan et al., 2015; Breyer et al., 2016; Zumberge et al., 2016) as shown in Figure 1 Well logs of the studied Eagle Ford well in Dewitt County the Th/U ratios measured from cores have more variations than the Th/U ratios from well logging though the trends of the two curves are quite the same Since the hand-held spectral core gamma instrument collects Th U and K data every 0.17 ft (5 cm) along the core samples it can collect spectral gamma of layers with different characteristics spectral core gamma measurement can avoid well bore environmental distortion Based on well log and core sample analysis, there are distinct differences in reservoir properties of the marl and limestone layers. As depicted in Figure 2 samples from the marl layers are darker and flakier than those from limestone layers XRD results show that the calcite content of marl layers ranges from 30% to 70% and clay content ranges from 20% to 50% The interbedded limestone layers contain less clay (5%–30%) and more calcite (55%–90%) than marl layers Left: Marl and limestone layers of the Eagle Ford Formation in Dewitt County Texas (A,C) Core samples from marl layers; (B,D) core samples from limestone layers Right: Ternary plot of the marl and limestone layers in the Eagle Ford and Buda Formation Vs can be estimated based on the proposed correlations especially in the marl layers of Upper Eagle Ford interbedded limestone layers of Lower Eagle Ford and the Buda Limestone layers Correlations of compressional and shear velocity in Dewitt County Correlations of compressional and shear velocity of Eagle Ford well in Dewitt County (in m/s) The elastic properties of different layers and the correlations between elastic properties and gamma ray intensity are shows in Figures 4, 5, 6, 7 and Tables 2, 3. According to Figures 4, 5 compressional and shear velocities have a power law relationship with gamma ray The Buda Limestone on the upper left of the figures shows the lowest gamma ray (ranging from 18 API to 48 API) and highest compressional velocity (ranging from 4981 m/s to 5949 m/s) and shear velocity (ranging from 2701 m/s to 3181 m/s) the Eagle Ford layers have much lower sonic velocities Correlations of compressional velocity and gamma ray in different layers Correlations of shear velocity and gamma ray in different layers Correlations of dynamic Young’s Modulus and gamma ray in different layers Correlations of dynamic Poisson’s ratio and gamma ray in different layers shear velocity and gamma ray of Eagle Ford well in Dewitt County (in m/s) Summary of parameters in different layers of the Eagle Ford and adjacent formation in Dewitt County Among the marl and interbedded limestone layers in the upper and lower Eagle Ford marl layers of the lower Eagle Ford have the highest average value of gamma ray 97 API and lowest average values of compressional velocity 3496 m/s and shear velocity 2027 m/s interbedded limestone layers of the upper Eagle Ford have the lowest average values of gamma ray 57 API and highest average value of compressional velocity 3751 m/s and shear velocity 2084 m/s Table 2 shows the correlation of compressional velocity shear velocity and gamma ray in different layers of the Eagle Ford well in Dewitt County (in m/s) In the marl and interbedded limestone layers in the Upper Eagle Ford there is a good negative linear relationship between the sonic velocities and gamma ray intensity in the Lower Eagle Ford and Buda Limestone there is a weak or no correlation between compressional velocity Attention should be paid when R2 is used to evaluate the fit of nonlinear relationships Since R2 is calculated based on the linear regression model assumption the increase of R2 does not always relate to better nonlinear models Based on compressional and shear velocities, the mechanical properties such as dynamic Young’s modulus and dynamic Poisson’s ratio can be obtained through Eqs 3, 4 where Ed is the dynamic Young’s modulus of rock MPsi; υm is the dynamic Poisson’s ratio of rock dimensionless; ρb is density of rock g/cm3; Vp is the compressional velocity of rock The mechanical properties of different layer and the correlation of mechanical properties with gamma ray intensity are shown in Figures 6, 7 and Table 3. Figure 6 depicts the relationship between dynamic Young’s modulus and gamma ray Young’s modulus decreases with gamma ray and the data points fall into two clusters Buda limestone shows the higher dynamic Young’s modulus with an average value of 8.9 Mpsi and the Eagle Ford Formation has much lower dynamic Young’s modulus marl layers of the lower Eagle Ford have the lowest averaged value of dynamic Young’s modulus (3.6 Mpsi) while the limestone layers of the upper Eagle Ford have the highest averaged value (4.5 Mpsi) In addition to the cross plots of compressional velocity, shear velocity and dynamic Young’s modulus against gamma ray, the relationships between dynamic Poisson’s ratio and gamma ray in different layers are also explored. As shown in Figure 7 there is no obvious difference among the three formations and no linear correlation between Poisson’s ratio and gamma ray There is no obvious difference in Poisson’s ratio in the Eagle Ford Formation and the Buda Limestone The average values of Poisson’s ratio in the Buda Limestone For a better understanding of the elastic properties of the Eagle Ford Formation, another well located in La Salle County, Texas was studied. Figure 8 shows the maturity level of samples from the two wells Samples from La Salle County are in the oil window and most samples from Dewitt County are in the condensate gas and dry gas window The well log information of the well in La Salle County is shown in Figure 9 The Eagle Ford Formation has higher gamma ray intensity lower calcite content than the overlying Austin Chalk and the underlying Buda Limestone The contact between the Upper and Lower Eagle Ford is marked by an increase in the gamma ray shows lower bulk density and higher resistivity than the Upper Eagle Ford showing the Eagle Ford shale and the adjacent formation unit At depth interval 2420 m–2423 m, the peak of potassium in the Upper Eagle Ford indicates the existence of ash bed layer (Mokhtari et al., 2016), which has much higher clay content than other parts of the formation. The features of ash bed are consistent with the results of Kiipli et al. (2008) Ash bed layers differ from the host rock by high concentrations of Al According to the contents of calcite and clay, we set a threshold of 75 API for categorizing limestone and marl layers in the upper Eagle Ford and a threshold of 105 API in the Lower Eagle Ford. The correlations between compressional and shear velocity in the Eagle Ford Formation and adjacent Buda Limestone are shown in Figure 10 Correlations of compressional and shear velocity in La Salle County There is a good positive linear relationship between compressional and shear velocity. Among the three correlations, Vs = 0.518 Vp + 240.56 is the best fit line for the data of Eagle Ford, the overlying Austin Chalk and the underlying Buda Limestone. The correlations in different layers of the Eagle Ford well in La Salle County are summarized in Table 4 Vs can be estimated based on the proposed correlation especially in the Lower Eagle Ford Formation Correlations of compressional and shear velocities of Eagle Ford well in La Salle County (in m/s) The elastic properties of different layer and the correlation between elastic properties and gamma ray intensity and clay content are shown in Figures 11, 12, 13, 14 and Table 5. According to Figures 11, 12, and Table 5 compressional and shear velocities have good negative linear relationships with gamma ray The Buda Limestone on the upper left of the figures shows the lowest gamma ray (ranging from 17 API to 40 API) and highest compressional velocity (ranging from 5546 m/s to 5857 m/s) and shear velocity (ranging from 3082 m/s to 3333 m/s) The Austin Chalk has higher gamma ray (ranging from 23 API to 113 API) lower compressional velocity (ranging from 4728 m/s to 5370 m/s) and shear velocity (ranging from 2624 m/s to 3031 m/s) than the Buda Limestone Correlations of dynamic Young’s Modulus and clay content in different layers Summary of elastic parameters in different layers of the Eagle Ford and adjacent formation in La Salle County Among the marl and limestone layers in the upper and lower Eagle Ford marl layers of the lower Eagle Ford have the highest average value of gamma ray 115 API lowest average values of compressional velocity 3892 m/s and shear velocity 2243 m/s limestone layers of the upper Eagle Ford have the lowest average values of gamma ray 63 API and highest average value of compressional velocity 4275 m/s and shear velocity 2480 m/s The correlations of compressional velocity shear velocity and gamma ray show that there is a weak or no relationship between sonic velocities and gamma ray in different layers of the Eagle Ford well in La Salle County Figure 13 depicts the relationship between dynamic Young’s modulus and gamma ray Young’s moduli decrease with gamma ray and the data points fall into three clusters Buda limestone shows the highest Young’s modulus with an average value of 10.3 Mpsi and the Eagle Ford Formation has the lowest Young’s modulus marl layers of the lower Eagle Ford have the lowest averaged value of Young’s modulus (4.5 Mpsi) while the limestone layers of the upper Eagle Ford have the highest averaged value (5.7 Mpsi) Figure 14 depicts the relationship between dynamic Young’s modulus and clay content there is a clear difference among the group of Austin Chalk But the negative linear relationship between Young’s modulus and clay content is relatively weak The comparison of elastic parameters in different layers of two Eagle Ford wells is shown in Table 6 Buda Limestone has the least variations in gamma ray intensity compressional and shear velocities and Young’s moduli in these two wells Compressional and shear velocities of the well in La Salle County are more than 11% higher than the well in Dewitt County in marl and limestone layers of the Eagle Ford Formation It can be seen from the comparison of mechanical properties of two Eagle Ford wells that dynamic Poisson’s ratio of two wells is similar while dynamic Young’s modulus in La Salle County is more than 25% higher than in Dewitt County Comparison of elastic parameters in different layers of two Eagle Ford wells The San Marcos Arch traverses the Eagle Ford play and extends towards the Gulf of Mexico southeasterly The Edwards City shelf margin and the Sligo shelf margin spread toward southwest in parallel and then separate the well in La Salle County is on the north side of the Edwards City shelf margin while the well in Dewitt County is close to the Edwards Reef Margin and the Sligo Reef Margin Both of these two wells are on the southwest side of the San Marcos arch caution should be paid when these results are generalized to other areas which are on the northeast side of the San Marcos arch Characterization of elastic properties of the marl and limestone layers in shale formations is crucial to hydraulic fracture design The aperture or aspect ratio of fractures can be affected by factors such as layer thickness ratio The modulus contrast between adjacent layers is an essential factor in the investigation of fracturing behaviours and the effect of elastic properties on fracture aperture should be analyzed The FEM models of layered shale with an unconfined fracture and confined fractures are shown in Figure 15 several assumptions are made: 1) there is no slip and opening along the layer boundaries; 2) there is a plane strain condition for the entire model; 3) the marl layers that are adjacent to the middle limestone layer have the same elastic properties The bottom boundary is fixed in the y direction and the middle point of the bottom boundary is fixed in the x direction so uy(B)=0 and ux(B)=0 at x=0 A constant displacement condition is imposed along the left and right boundaries so ux(L)= -ux and ux(R)=ux FEM model and its boundary conditions of layered shale (A) Unconfined fracture model; (B) confined fracture model with three fractures (revised from Bai et al. three fractures are equally spaced and the fracture height is equal to the thickness of the limestone layer In order to investigate the effects of elastic properties of the marl and limestone layers on the fracture aspect ratio, one parameter is changed at one time and other parameters are kept constant. Figure 16 shows that the relative change of the unconfined fracture aspect ratio is positively related to the ratio of the Young’s modulus of the limestone layer to that of the marl layer (El/Em) Correlations of relative change of aspect ratio and Young’s modulus ratio of adjacent layers in unconfined fracture model (υm=υl=0.25 According to the elastic properties of the Eagle Ford Shale in Dewitt County (shown in Table 3), the Young’s modulus ratio of the Upper Eagle Ford Shale ranges from 1.0 to 2.2, while the ratio of the Lower Eagle Ford Shale ranges from 1.0 to 1.7. According to the elastic properties of the Eagle Ford Shale in La Salle County (shown in Table 5) the Young’s modulus ratio of the Upper Eagle Ford Shale ranges from 1.3 to 1.7 while the ratio of the Lower Eagle Ford Shale ranges from 1.0 to 1.7 the relative change of aspect ratio with respect to the Young’s modulus ratio is less than 0.1% Figure 17 illustrates the variations of the relative change of aspect ratio with Poisson’s ratio. As shown in Table 3, the Poisson’s ratio of the Upper and Lower Eagle Ford Shale in Dewitt county ranges from 0.21 to 0.33 and 0.18 to 0.33, respectively. As shown in Table 5 the Poisson’s ratio of the Upper and Lower Eagle Ford Shale in La Salle County ranges from 0.20 to 0.32 and 0.18 to 0.30 the absolute value of relative change of aspect ratio with respect to the ratio of Poisson’s ratio is less than 0.01% Correlations of relative change of aspect ratio and Poisson’s ratio in unconfined fracture model (Em=El=5 MPsi It can be concluded from Figures 16, 17 that the influence of elastic properties of the Eagle Ford Shale on the aspect ratio of the unconfined fracture can be negligible in these two areas The effect of elastic properties of the layered shale on the aspect ratio of confined fractures is shown in Figures 18, 19. Figure 18 shows the relative change of aspect ratio increases with the ratio of the Young’s modulus of limestone layer to that of the marl layer the relative change of aspect ratio increases significantly when the ratio of fracture spacing to layer thickness is low Correlations of relative change of aspect ratio and Young’s modulus ratio of adjacent layers in confined fracture model (υm=υl=0.25 Correlations of relative change of aspect ratio and Poisson’s ratio in confined fracture model (Em=El=5 MPsi Taking the Eagle Ford Shale in Dewitt County as an example the ratio of Young’s modulus ranges from 1.0 to 2.2 and from 1.0 to 1.7 in the Upper and Lower Eagle Ford The corresponding relative change of aspect ratio can reach up to 14% when S/H equals 0.5 Correlations of the relative change of aspect ratio and Poisson’s ratio in the confined fracture model are shown in Figure 19 Taking the Eagle Ford Shale in La Salle County as an example the Poisson’s ratio ranges from 0.20 to 0.32 and from 0.18 to 0.30 in the Upper and Lower Eagle Ford respectively The corresponding relative change of aspect ratio is less than 1% indicating the effect of Poisson’s ratio on aspect ratio is negligible The elastic properties of the marl and limestone layers in the Eagle Ford Shale were analyzed in this study the effect of elastic properties on aspect ratio of unconfined and confined fractures were evaluated (1) Shear velocity has a positive linear relationship with compressional velocity in the Eagle Ford and adjacent formations Two relationships including Vs = 0.498 Vp + 250.85 and Vs = 0.518 Vp + 240.56 were developed for two wells with R2 value of 0.96 Correlations of shear velocity and compressional velocity in marl and interbedded limestone layers of Eagle Ford Formation were obtained (2) There are power law or negative linear relationships between compressional velocity dynamic Young’s modulus and gamma ray intensity in the Eagle Ford well in Dewitt County and La Salle County No correlation between Poisson’s ratio and gamma ray or clay content exists (3) Comparison of elastic properties shows that there are more variations in dynamic Young’s modulus less variations in compressional and shear velocities and no obvious difference in dynamic Poisson’s ratio (4) The effect of Young’s modulus ratio on the aspect ratio of confined fractures is remarkable when the ratio of fracture spacing to layer thickness is low while the influence of elastic properties contrast of shale layers on the aspect ratio of the unconfined fracture can be negligible in the Eagle Ford wells in Dewitt County and La Salle County The original contributions presented in the study are included in the article/supplementary material further inquiries can be directed to the corresponding author All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher Shale elastic property relationships as a function of total organic carbon content using synthetic samples CrossRef Full Text | Google Scholar and production in the Eagle Ford shale (cretaceous) between the san Marcos arch and the maverick basin Google Scholar Relationships between compressional-wave and shear-wave velocities in clastic silicate rocks CrossRef Full Text | Google Scholar Rock physics – the link between rock properties and AVO response Google Scholar Chronostratigraphic relationships of the woodbine and Eagle Ford groups across Texas Google Scholar Shear-wave velocity estimation in porous rocks: Theoretical formulation CrossRef Full Text | Google Scholar Effects of porosity and clay content on wave velocities in sandstones CrossRef Full Text | Google Scholar Vp-Vs relationship and amplitude variation with offset modelling of glauconitic greensand CrossRef Full Text | Google Scholar CrossRef Full Text | Google Scholar Characterization of marl and interbedded limestone layers in the Eagle Ford Formation CrossRef Full Text | Google Scholar Geochemistry of telichian (silurian) K-bentonites in Estonia and Latvia CrossRef Full Text | Google Scholar New geomechanical application utilizing MWD gamma ray logs: An Eagle Ford case study CrossRef Full Text | Google Scholar Characterization of elastic anisotropy in Eagle Ford shale: Impact of heterogeneity and measurement scale CrossRef Full Text | Google Scholar Acoustic character logs and their applications in formation evaluation CrossRef Full Text | Google Scholar The relationship between acoustic properties and the petrographic character of carbonate rocks CrossRef Full Text | Google Scholar Estimation of net-to-gross from P and S impedance in deepwater turbidites CrossRef Full Text | Google Scholar A new velocity model for clay-sand mixtures CrossRef Full Text | Google Scholar A physical model for shear-wave velocity prediction CrossRef Full Text | Google Scholar Roles of multicomponent adsorption and geomechanics in the development of an Eagle Ford shale condensate reservoir CrossRef Full Text | Google Scholar Petroleum geochemistry of the cenomanian–turonian Eagle Ford oils of south Texas Google Scholar Mokhtari M and Song J (2023) Comparative study of elastic properties of marl and limestone layers in the Eagle Ford formation Received: 20 October 2022; Accepted: 11 November 2022;Published: 10 January 2023 Copyright © 2023 Jiang, Mokhtari and Song. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited *Correspondence: Mehdi Mokhtari, bXhtNDQ4N0Bsb3Vpc2lhbmEuZWR1 2025) – A fatal car crash occurred on Saturday resulting in the death of one individual and injuries to another on Dupont Parkway (US-13) just north of Marl Pit Road a Toyota Prius was traveling northbound in the left lane of Dupont Pkwy southbound a Ford Mustang was traveling southbound in the left lane of the same roadway sustained critical injuries and was transported by ambulance to a nearby hospital His identity is being withheld pending family notification suffered non-life-threatening injuries and was transported to a local hospital for treatment Authorities did not provide details regarding the driver of the Mustang The roadway remained closed for approximately five hours while the Delaware State Police Troop 2 Collision Reconstruction Unit conducted its investigation and emergency crews worked to clear the wreckage Our heartfelt condolences go out to the family of the deceased victim has seen a significant number of fatal car accidents in recent years contributing to concerns about road safety in the area Some of these accidents have involved impaired or reckless drivers highlighting the need for more effective measures to protect residents and visitors Local authorities have responded by implementing traffic safety initiatives including the introduction of traffic cameras in high-risk zones These efforts aim to reduce speeding and improve safety particularly in areas near schools and busy intersections When a fatal car accident occurs due to someone else’s negligence the surviving family members in Middletown may be eligible to file a wrongful death lawsuit the statute of limitations for wrongful death claims is generally two years from the date of death These lawsuits can help families recover compensation for funeral expenses Families must seek legal advice from an experienced wrongful death attorney to understand their rights and ensure that they receive the compensation they deserve If you have lost a loved one in a fatal car accident locally, our compassionate and bold Middletown wrongful death attorney at Murphy & Landon will build and handle a strong and compelling claim to get you compensation for burial costs and other damages derived from your tragic loss With a firm commitment to client advocacy and a long track record of success our efficient legal team provides quality legal representation to grieving families who have lost a loved one due to a careless motorist To speak with our attorney about your loved one’s fatal Middletown car accident call Murphy & Landon at (302) 472-8112 to arrange a complimentary consultation Our vigorous legal team is ready to guide you through the claims process and ensure that your rights and interests are fiercely defended Note: Our law firm utilizes secondary sources to create this post The facts surrounding this specific accident have not been independently verified Contact Murphy & Landon if you locate any inaccurate information We will update the post right away to reflect the most accurate information available Disclaimer: None of the information in this post is intended to be legal advice or medical advice The photo used in this post was not taken at this accident scene Murphy & Landon Delaware 1011 Centre Road Suite 210 Wilmington, DE 19805 Map and Directions Murphy & Landon New York 800 Third Avenue 28th Floor New York, NY 10022 Map and Directions Get Directions powered by Google MORGANTOWN — While the exact route remains a work in progress Monongalia County appears to be in the path of a major power transmission project representatives of NextEra Energy Transmission sat down with members of the Monongalia County Commission to discuss the Mid-Atlantic Resiliency Link (MARL) a 105-mile transmission line that’s going to run from Greene County Think about it as if it’s a major highway for energy and electrons,” NextEra Energy Transmission Senior Director Kaitlin McCormick said “We have a small component in Pennsylvania then we’ll be crossing through West Virginia back into West Virginia and then ending in Virginia.”  When pressed for any specifics in terms of potential location McCormick explained NextEra was looking at the northern part of the county “I think we’re primarily looking at areas that don’t have zoning districts within them.” PJM Interconnection manages the electrical transmission system for a 13-state region that runs from Michigan to Tennessee and from Illinois to Delaware for which PJM is predicting a dramatic increase in the  number of power-hungry data centers coming online “PJM is working through a lot of stuff and a lot of changes as demand for electricity changes particularly there are some major industrial users that are looking for things It’s a total change in landscape and we’re just a piece of that,” McCormick said NextEra’s MARL project was one of several selected by PJM to help meet the region’s shifting power demands NextEra Energy Transmission MidAtlantic will finance operate and maintain the transmission line which is expected to take two years to construct it’s not affiliated with any one generation source or any one power source It’s just working to help provide a backbone to move electricity across the grid and through the region,” McCormick said “That’s a major capital investment here in the region and in the state and in Mon County as well.” postcards will go out to anyone living within a miles-wide swath identified for the potential route That study area will be centered around existing transmission corridors.  McCormick said the company wants to run the line parallel to existing infrastructure “We recognize some of those transmission lines have been there for decades and where we can’t parallel we’re looking to go around some of the human environment that’s built up around that,” she said The company will ultimately need a 200-foot wide right of way.  Interactive online maps and a survey will be part of the public feedback process as will a public comment period and open meetings tentatively planned for the March/April 2025 timeframe “Juice Crew Allstars” hit the streets as a seven-minute posse cut a B-side to “Evolution” on a Cold Chillin’ Records 12-inch and it still reverberates through Hip Hop’s golden age like a boombox on a Queensbridge stoop and a very young Tragedy Khadafi over a beat that grooves with funky horns and crisp TJ Swan’s smooth chorus—“Juice Crew Allstars”—hooks you in while the MCs trade bars with a swagger that’s pure ’80s bravado and the mood crackles with crew pride—an artifact of a time when Hip Hop was raw this song is a cornerstone of the Juice Crew’s legacy and a window into Marley Marl’s seismic influence on the genre Marley Marl’s Juice Crew wasn’t a group born overnight Magic’s DJ on WBLS’s Rapp Attack—the first all-Hip Hop radio show on a major station dubbed “Sir Juice,” gave the crew its name Starting with 1983’s “Sucker DJ’s (I Will Survive)” by Dimples D.—a retort to Run-DMC’s “Sucker M.C.’s”—Marley kicked off a tradition of answer records a chance meeting with 15-year-old Roxanne Shanté birthed “Roxanne’s Revenge,” a scathing clapback to UTFO’s “Roxanne and the vibe bristles with teenage defiance It ignited the Roxanne Wars—dozens of response records—and put Cold Chillin’ Records Marley’s cousin MC Shan dropped “The Bridge” in 1986 a love letter to Queensbridge with a bassline that rumbles low and drums from The Honey Drippers’ “Impeach the President” snapping clean The track’s chill groove hides a bomb—Boogie Down Productions (BDP) took it as a claim that Queens birthed Hip Hop Shan and Marley fired “Kill That Noise” on Down By Law but KRS’s “The Bridge Is Over” sealed the feud with a piano loop and a taunting flow The clash wasn’t just noise—it sharpened Hip Hop’s edge “Juice Crew Allstars” arrived in this heat his voice slicing through the funky horn sample like a blade his charisma painting vivid lines over the steady beat while MC Shan’s verse struts with veteran ease and Tragedy Khadafi—then MC Percy—darkens the mood The structure’s a relay—each MC grabs the mic Marley keeps it lean: no overblown effects just a tight loop and drums that hit your chest The sample—a nod to Shanté’s “Roxanne’s Revenge”—ties it to the crew’s roots This wasn’t Marley’s most famous posse cut—1988’s “The Symphony” with Masta Ace and Big Daddy Kane often steals that crown with its Otis Redding “Hard to Handle” piano and sparse it’s less a polished showcase than a street-level rally cry The beat’s funk-driven pulse and the MCs’ competitive spits make it a time capsule—Hip Hop before sampling laws tightened when producers like Marley could flip anything and MCs could flex without a hook-heavy formula The Juice Crew’s roster grew legendary—Big Daddy Kane’s suave flow Kool G Rap’s street tales—but “Juice Crew Allstars” spotlights the early core beats were stiff—synthetic drums and basic loops chopping samples with an MPC like a jazz drummer “Juice Crew Allstars” grooves loose yet tight the horns bright—a blueprint for the ’90s boom-bap wave The Juice Crew bridged old-school party vibes with the new school’s lyrical flex born from Queensbridge’s projects but echoing everywhere They fueled the posse cut trend—think Wu-Tang or Boot Camp Clik—and their beefs the crew’s DNA lingered—Nas’ “Da Bridge 2001” with Mobb Deep and Tragedy nodded back “Juice Crew Allstars” isn’t a chart-topper or a polished gem—it’s a crew anthem, rough around the edges, pulsing with 1987’s golden-age grit. For HHGA, it’s a reminder of Marley Marl’s genius: a producer who turned Queensbridge into a sound and website in this browser for the next time I comment Enter your email address to subscribe to our newsletter (WXYZ) — An animal shelter in Pontiac is reaching out to fill the plates of cats and dogs this Thanksgiving A $25 donation will provide a pet-friendly holiday meal to animals at the Michigan Animal Rescue League It includes special versions of classics like savory green beans and sweet potatoes Donations will also go toward rescuing and caring for animals at MARL You can watch them enjoy their meals on the shelter's Facebook, Instagram and TikTok pages If you're interested in donating, visit marl.org The Saline Area Senior Center (SASC) is preparing for its upcoming 11th Annual Mayor’s Senior Conference on Friday the complimentary event provides valuable educational content and updates on topics that matter to senior citizens in the area The conference promises to deliver a dynamic lineup of sessions and activities designed to enhance the lives of Saline’s senior residents Saline Senior Center Program Coordinator Andrea Lewis told STN “Our goal is to bring together–not just the regulars from the senior center but any senior in the area–for a day filled with learning and community.”  The ½ day conference is scheduled to kick off at 8:30am with a continental breakfast sponsored by Brookdale Senior Living The programming includes opening remarks by Mayor Marl a panel discussion with regional municipal leaders moderated by Mayor Marl The conference then concludes with a lunch sponsored by the Mayor.  The conference will be held at the Saline Area Senior Center but folks do not need to be a member of the Senior Center to attend space is limited and pre-registration is required.  To register or learn more interested seniors must stop by or call the Saline Senior Center at 734-429-9274.  More information about the Saline Area Senior Center, its programs and membership, and the Mayor’s Annual Seniors Conference can be found on the Saline Senior Center website The Sun Times News is the hub of the most useful information in Chelsea Subscribe to our free daily newsletter to stay on top of all the local news Glamox has entered into an agreement to acquire the UK based company MARL International MARL International is located in Ulverston UK and has over 50 years' experience in the design and manufacture of electronic systems The acquisition of MARL International will provide the Glamox Group with a leading lighting solution range in the growing defense and navy markets The defense and navy markets are expanding and exhibits favorable characteristics that align with Glamox' strategic growth objectives the UK Navy stands out as an especially attractive partner due to its track record of exporting advanced vessel designs the navy sector demands high quality and reliability which aligns well with Glamox' expertise and innovation-driven approach This acquisition would enable Glamox to leverage these strengths and enhance its competitive position in the maritime industry MARL had total revenues of GBP 6,0 mGBP for the 2023/24 financial year with close to 60% coming from Navy projects All 62 employees are based in the United Kingdom The company specializes in designing and providing high performance LED lighting solutions in highly technical environments for domestic and international customers in Navy Group Chief Executive Officer Astrid Simonsen Joos highlighted: “With MARL’s capabilities dedicated employees and growth within the Navy segment this strategic acquisition aligns with our ambitions we will be better equipped to serve our customers with cutting-edge solutions within the Navy segment.” “The growing market for sustainable lighting solutions within the Navy and marine segments is continuing to be a profitable opportunity for Glamox and with MARL onboard as a part of the team we are positioned well for growth” says Simonsen Joos MARL International's main owner and managing director is enthusiastic about the new opportunity: “We are thrilled to see our company join forces with a solid international lighting company with a focus on innovation Their commitment to excellence and forward-thinking approach ensures a bright future for our employees MARL International will be a part of the Glamox Marine The products and services herein described in this press release are not endorsed by The Maritime Executive Fireworks are a tradition at most Fourth of July celebrations, but the loud booms from these displays can cause anxiety for area pets and animals. One local rescue, Michigan Animal Rescue League (MARL) is keeping the cats and dogs in its care calm this year with a new and unique program called “Comfort Crew.” Each night when Fourth of July fireworks are expected staff and volunteers at the Pontiac-based rescue will stay at the shelter until midnight to offer the adoptable pets soft music and other activities and treats aimed at keeping them distracted during the displays The goal of this hands-on approach is to “ease the stress and anxiety caused by loud noises “As ‘A Different Breed of Shelter,’ we want to ensure the comfort of our dogs and cats at all times,” Magee Humes “Recognizing that fireworks can cause stress in animals our team of staff and volunteers jumped at the chance to stay late to provide comfort and security to the over 200 animals currently in our care.” After one night, staff at MARL are confident that the Comfort Crew will become an annual tradition for the rescue, and while it is too late to help this Fourth of July, Humes told Hour Detroit that the rescue is always looking for volunteers willing to be trained by the rescue to help care for the cats and dogs all year round Those trained to work with cats will learn about enrichment activities for them and how to watch their behavior as well as how to clean and handle them volunteers who work with dogs learn how to put a harness on and walk them what to do if you encounter another dog on a walk Volunteers at the rescue must be at least 18 years of age For more information about the Comfort Crew and other volunteer opportunities at MARL, visit marl.org Traci Husse Saline Mayor Brian Marl officially kicked off his campaign for reelection on Thursday with a reception at Mac’s Acadian Seafood Shack Despite rainy weather and coinciding with the downtown’s Ladies Night Out around 100 guests gathered to support Marl’s announcement In an interview with The Sun Times News (STN) Marl expressed his gratitude for the turnout noting he was particularly honored to have friends such as U.S Representative Debbie Dingell and State Representative Felicia Brabec in attendance “Minus the weather and the conflict with Ladies Night Out “We packed the space at Mac’s and I was very honored to have Debbie Dingell as the guest of honor.” STN asked Marl about potential challengers for the mayoral race but the filing deadline is still weeks away with plenty of time to complete paperwork and collect signatures and dialogue and provides the voters with a choice I think there’s always something inherently beneficial about that.” Currently serving his twelfth year in office Marl highlighted the importance of service when asked why he chose local politics as a profession It’s the place that I was born and raised and on my mother’s side we’ve been here for five or six generations,” he stated The services that we provide here at the City of Saline are some of the most valued and some of the most important services that a government provides to citizens and business owners–police What happens when things go awry with those services and people direct their anger toward city officials If you’re going to choose this as a vocation you have to have a thick skin and you have to come to terms with the fact that people will impugn your judgment that criticism is conveyed in a constructive manner I’m able to learn and grow and improve from receiving it.”  he says he will remain focused on five key long-term priorities: financial stewardship and openness and transparency in city government The St Andrew South Criminal Investigation Branch on Thursday charged 24-year-old Malik Peart of Ambroke Lane in the parish for fatal shooting a man in the head on Lower Marl Road in 2023 Frekleton was at the location when he was pounced upon by Peart who was armed with a firearm Peart allegedly opened gunfire hitting Frekleton in the head and upper body Peart was formally charged following an eyewitness statement and a question-and-answer session in the presence of his attorney Follow The Gleaner on X, formerly Twitter, and Instagram @JamaicaGleaner and on Facebook @GleanerJamaica. Send us a message on WhatsApp at 1-876-499-0169 or email us at onlinefeedback@gleanerjm.com or editors@gleanerjm.com View the discussion thread. CU News , The Fine Arts and Cultural Management Office of Chulalongkorn University invites you to visit the “Wisdom Through Canvas: The Art of Marl and Tamarind Seed Glue” exhibition featuring works by artists, students, and faculty members from the Department of Art, Music, and Dance, Faculty of Education The exhibition will be held from March 27 to June 6 The opening ceremony will take place on Tuesday Vice President of Chulalongkorn University The exhibition reflects the concept of “Preserving and Conserving Thai Wisdom.” It features works created by 36 artists and faculty members from the Art Education program in the Department of Art They collectively explored and experimented with canvas frames supported by Marl and tamarind seed glue—an innovation that combines traditional Thai wisdom with contemporary art The exhibition is supported by information from KCT Conservation Co. experts in the conservation of fine arts.  The exhibition is open daily from Monday to Friday please contact 0-2218-3645-6 or 0-2218-3624 Facebook: Chulamuseum   Chula Leads Dialogue on Thai Business Resilience in Logistics Amidst Global Trade Disruptions  Chula Student Wins Best Poster Award at International Conference in Malaysia  Sasin and SCGC Ignite Startup Impact, Driving Business Transformation Toward Sustainability at the Bangkok Business Challenge 2025—Growing Impactful Ventures  Chula Law Students Bring Honor to Thailand at the International Law Moot Court Competition in the U.S.  Chula–BAT Partnership to Advance Sports Science and Develop Athletes  Chula Wins Top Innovation Prize at THE Asia Awards 2025 The sense of kinship and warmth found in the Chula community is priceless and a treasure worth keeping This website uses cookies to personalize content ท่านสามารถเลือกการตั้งค่าคุกกี้โดยเปิด/ปิด คุกกี้ในแต่ละประเภทได้ตามความต้องการ ยกเว้น คุกกี้ที่จำเป็น This subscription allows you article access for 1 day or sign up for a new account to continue reading Thank you for visiting myfenton.com,your new daily Tri-County Times news source Click here for details We hope that you continue to enjoy our free content Checking back? Since you viewed this item previously you can read it again. Cloudy with periods of rain. Low 51F. Winds N at 10 to 15 mph. Chance of rain 80%. Rainfall near a quarter of an inch. Shown here is Austin Berger with his father James Berger, sister Mandy Gidelski and his mother Lisa Berger when he graduated from UM-Flint. Genesee County Sheriff’s Dive Team members (from left) Dep. Evan Myers, Dep. Connor Storms and Dep. Miles Allen prepare to search a spot in Marl Lake identified by the Aqua Eye provided by Oakland County at 8:30 p.m. on Tuesday, June 25.   Genesee County Sheriff Chris Swanson reported Thursday afternoon that the body of Austin James Berger, 33, of Fenton Township, was recovered from Marl Lake at approximately noon.  On Tuesday, June 25, the sheriff’s office were alerted to his disappearance by a 911 call at 1:30 p.m. It was reported that Berger was a vulnerable adult and he was last seen Sunday, June 23 at 8:15 p.m. in the 16000 block of Hi Land Trail in Fenton Township.  Swanson said Berger was known to walk the areas of Owen Road, downtown Fenton and Silver Parkway.  The sheriff said Berger’s eyeglasses were found at the end of a dock on Marl Lake. Sheriff’s deputies, its dive team, and the Oakland County Sheriff’s Office dive team immediately began searching the lake for Berger. Sonar equipment also was used.  Dive teams were back out Wednesday and Thursday to continue their search. The sheriff said a fisherman found Berger Thursday, June 27 approximately 800 yards from where he was reported missing.  Swanson said the family is absolutely devastated with the news of Berger’s death.  “He was a good man with a big heart,” he said. “He grew up on the lake.”  He added that there were no signs of foul play or self harm and the family is convinced he would never have hurt himself. An autopsy will be conducted.  The sheriff said, “It’s been a very violent and tragic year for water deaths,” as he mentioned recent drownings in the Flint River and Oakland County.  With the Fourth of July holiday approaching and the busiest time for activity on area lakes, Swanson is reminding everyone that “water is unforgiving.” He urges everyone enjoying the lakes not to take any chances, have spotters when pulling tubers or skiers, use life jackets, be in control of your watercraft and don’t drink and drive watercraft.  The Genesee County Sheriff’s Office Marine Division will be out in full force for the Fourth of July holiday but Swanson added, “It’s up to each and every one of us.”  Scott Henman, one of Austin’s many cousins spoke on behalf of Berger’s family.  Henman said that growing up on Marl Lake, Austin felt at home in or on the water. He was always willing to take anyone on the lake for tubing, fishing, swimming, or jet-skiing.  “While not on the water growing up, Austin stayed active with hockey from a young age through his graduation from Flint Powers Catholic High School in 2009 where he was recognized for his accomplishments and sportsmanship on and off the ice.   “Where Austin showed his greatest fortitude was navigating his personal mental health journey; exuding grit and resilience during the challenges he faced.  “His victories and growth inspired him to pursue a career in health care administration, for which he graduated with honors and a BS from the University of Michigan – Flint and was a passionate advocate for patients and their family support systems; much like his mother who made a career at Reach Resource Services in Flint.  “Austin valued his personal relationships and enjoyed being a part of his community. He was recognized by many as a regular at his favorite Fenton restaurants Leo’s Coney Island and Panera.  “The family would like to thank the first responders from the Genesee County Sheriff’s Office, Oakland County Sheriff’s Office, and the Fenton Township Fire Department; with a special thanks to the GCSO Marine Division and for the leadership of Det. Sgt. Scott Pritchard and Sheriff Chris Swanson for their compassionate, thorough and professional coordination of the search and investigation.  “Many more thanks go to the countless friends, colleagues, and local communities who reached out with overwhelming and much needed support. The community joined together in spreading the information from law enforcement and media outlets so widely that many tips and continued possible sightings kept hope alive for Austin’s safe return.  “Despite the outcome, Austin’s parents and family take solace in the support they have and are able to begin grieving. Arrangements are not yet finalized but will be made public when available.” Email notifications are only sent once a day, and only if there are new matching items. Your browser is out of date and potentially vulnerable to security risks.We recommend switching to one of the following browsers: Volume 12 - 2024 | https://doi.org/10.3389/feart.2024.1411126 Recent exploration has revealed that the Middle Triassic Leikoupo Formation 32 Submember (T2l32) in the Sichuan Basin contains unconventional marl reservoirs with significant natural gas potential the lithological understanding of T2l32 is incomplete and relies solely on inaccurate mud logs This lack of lithological foundation challenges geology and petroleum research this paper presents a double-hierarchical workflow to identify seven types of lithology using logs while the second order further subdivides marl into anhydrite marl Different rocks’ logging response characteristics are summarized based on quantity-limited cores and micro-resistivity imaging logs Lithological identification of 2D and 3D plots is established using sensitive GR Corresponding identification standards are built in two hierarchies the lithology of T2l32 is identified in a total of 119 wells the lithological characteristics of vertical and plane are discussed in the research area The research results may aid in comprehending the entire lithological characteristics of the complex marl reservoir in T2l32 of the Sichuan Basin It would help the exploration potential of petroleum systems in turn Marl reservoir exhibits poor physical properties with porosity ranging from 2% to 8% and permeabilities of (0.001–1) × 10−3 μm2 in T2l32 obtaining accurate geological information would be difficult in the T2l32 formation a hierarchical lithological identification method from logs is formed to solve the lithological problem of tight marl reservoir in T2l32 effectively Log response characteristics of different rocks are summarized on the quantity-limited cores and micro-resistivity imaging log Corresponding 2D and 3D lithological plots are established the lithological characteristics of T2l32 are discussed Figure 1. Tectonic of the Sichuan Basin and depositional background of T2l32. (A) Tectonic background of the Sichuan Basin (modified from Tian et al., 2021). (B) Depositional background of T2l32 in the Sichuan Basin (modified from Tian et al., 2021) Stratigraphic characteristics of the T2l32 in the central Sichuan Basin (A) Lithological characteristics of the Leikoupo Formation (B) Generalized open-hole stratigraphic T2l32 of CT1 Well Conventional logs: CAL-borehole diameter (in) RT-deep investigation resistivity (Ω·m) RXO-shallow investigation resistivity (Ω·m) (C) Core description and photos in CT1 Well The third stage summarizes the logging response characteristics of the above three categories and four types of lithologies The lithological evidence comes from mud logs The fourth stage produces several 2D and 3D lithological plots hierarchically from logs The fifth stage applies plots to identify lithology in boreholes and discusses the vertical and plane lithological characteristics of T2l32 in the Sichuan Basin Standardization of logging curves in some wells Hierarchical workflow of lithological identification in T2l32 Logging response characteristics of different lithologies (A) Logging response characteristics of first-order lithologies in GS1 Well (B) Logging response characteristics of second-order lithologies in JY1 Well The corresponding identification standard would be: salt GR<35 API RT>3,000 Ω·m; anhydrite GR<35 API RT>800 Ω·m; marl GR>30 API Lithological identification plots for the first-order lithologies of salt Lithology and logging data derived from coring intervals of CT1 and JY1 Well (B) 2D RT-GR plot; (C) 2D RT-DEN plot; (D) 3D GR-DEN-RT plot Lithological identification GR-RT plot for the second-order lithologies of anhydrite marl Lithology and logging data derived from coring intervals of JY1 Well Lithological identification standard of logs for complex marl reservoir of the T2l32 in the central Sichuan Basin To check the availability of the lithological identification standard, identifying results are compared with core lithology in CT1 Well. In the coring interval, 3,560–3,568.65 m, upper lithology is argillaceous limestone and lower lithology is shaly limestone in coring description. In the lithological identification result, the interval of 3,561.8–3,562.54 m is in higher GR than up and down, and lithology is recognized as shaly limestone Figure 8 Coincidence rate between coring identifying and lithology is about 91% centimeter-scale lithology would be acquired Water is hard to store in this tight marl reservoir the logging responses are principally rooted in the rock framework Different amount of pore fluids affects the GR Compare identification results with cores in CT1 Well Lithological identification results of LG47 Well Quantitative thickness statistics of different lithologies and maximum thickness of different lithologies (B) Total thickness percentage of different lithologies In the entire T2l32 formation, the percentage of salt thickness is 16.1%; the percentage of anhydrite thickness is 16.9%; the percentage of anhydrite marl thickness is 5.9%; the percentage of argillaceous limestone thickness is 27.6%; the percentage of shaly limestone thickness is 25.8%; the percentage of limy shale thickness is 7.7% (Figure 10B) These quantitative parameters reveal the characteristics of the different lithologies the individual thicknesses of the shaly limestone and argillaceous limestone are medium The total thicknesses of these two lithologies are the greatest the individual layer thicknesses of salt and anhydrite are large The total thickness of these two lithologies is the second the single-layer thickness of limy shale is the smallest During the deposition of the Middle Triassic Leikoupo Formation, uplifts were developed at the edge of the basin. The saline seawater was evaporated in the restricted platform in the arid paleoclimate. From the center to the margin of the Sichuan Basin, the depositional facies are anhydrite-salt lagoon, marly lagoon, lagoon margin of marly flat, dolomitic flat, and marly flat (Figure 1B) Based on the lithological identification results in individual boreholes, the lithological characteristics in the horizontal formation are interpreted in different depositional facies (Figure 11) is the thickest in the central anhydrite-salt lagoon and thins towards the basin margin The total thickness percentage of salt is reduced from the central to the marginal in the basin The number of layers and the total thickness of anhydrite decrease towards the margin of the basin as well The number of marl layers in the central basin is greater than in the marginal basin; The monolayer thickness and total percentage of marl thickness in the central basin are less than in the marginal basin Gases are well trapped in these thin marls Figure 11. Lithological characteristics in the horizontal formation of T2l32. The location of the wells is marked in Figure 1B Regional features of the preponderant reservoir and limy shale are crucial factors for further geological understanding These lithological characteristics of the region would offer an important reference for subsequent exploration and development of natural gas First-order lithological thickness plane spread of T2l32 Lithological thickness plane spread of marl in T2l32 (A) Thickness plane spread of anhydrite marl (B) Thickness plane spread of argillaceous limestone (C) Thickness plane spread of shaly limestone (1) Lithological identification of 2D and 3D plots is established for the complex marl reservoir in T2l32 of the Sichuan Basin Identification standard of the first-order lithology is: salt GR<35 API Identification standard of the fine lithology in marl is: anhydrite marl GR<35 API RT 800–2000 Ω·m; argillaceous limestone GR 30–50 API RT 200–2000 Ω·m; shaly limestone GR 40–60 API RT 30–300 Ω·m; limy shale GR>45 API the coincidence rate of identifying lithological results is larger than 90% while salt is just dominated in the southeastern The distribution of the marl is relatively wide and developed throughout the area mainly concentrated in the center NE-SW region and limy shale have practical significance for follow-up exploration in T2l32 of the central Sichuan Basin The data analyzed in this study is subject to the following licenses/restrictions: The dataset not available. Requests to access these datasets should be directed to ZW, MjAyMjcxMDM2N0B5YW5ndHpldS5lZHUuY24= The author(s) declare that no financial support was received for the research The reviewers are gratefully acknowledged for constructive comments that substantially improved the quality of this manuscript we appreciate the editor’s suggestions to revise this manuscript How facies and diagenesis affect fracturing of limestone beds and reservoir permeability in limestone–marl alternations CrossRef Full Text | Google Scholar Chemostratigraphy of unconventional shale reservoirs: a case study of the Niobrara Formation within the Denver-Julesburg Basin CrossRef Full Text | Google Scholar Aptian-Lower Albian Serdj carbonate platform of the Tunisian Atlas: development CrossRef Full Text | Google Scholar The use of microresistivity image logs for facies interpretations: an example in point-bar deposits of the McMurray Formation CrossRef Full Text | Google Scholar Proportional integral derivative controller used to simulate the mineral concentration and fluid saturations from geological data and well logs in the Namorado reservoir CrossRef Full Text | Google Scholar Maturity assessment of solid bitumen in the Sinian carbonate reservoirs of the eastern and central Sichuan Basin China: Application for hydrocarbon generation modelling CrossRef Full Text | Google Scholar Deep-sea trace fossils and depositional model from the lower Miocene Tiaret marl formation (northwestern Algeria) CrossRef Full Text | Google Scholar Utilising borehole image logs to interpret delta to estuarine system: a case study of the subsurface Lower Jurassic Cook Formation in the Norwegian northern North Sea CrossRef Full Text | Google Scholar Petrophysical evaluation of well log data and rock physics modeling for characterization of Eocene reservoir in Chandmari oil field of Assam-Arakan Basin India CrossRef Full Text | Google Scholar Fracture mechanical properties of carbonate and evaporite caprocks in 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approach based on machine learning with evolutionary parameter tuning CrossRef Full Text | Google Scholar Origin of Triassic Leikoupo dolostone reservoirs in Sichuan Basin CrossRef Full Text | Google Scholar Sedimentary characteristics and control factors of anhydrite-salt rocks in the Paleogene Xingouzui formation in Jiangling Depression CrossRef Full Text | Google Scholar Application of seismic geomorphology to carbonate rocks: a case study of the Cambrian Longwangmiao formation in the Gaoshiti-Moxi area CrossRef Full Text | Google Scholar General depositional features of the carbonate platform gas reservoir of the Lower Triassic Jialingjiang Formation in the Sichuan Basin of southwest China: Moxi gas field of the central basin CrossRef Full Text | Google Scholar Well logging petrophysical experiment analysis of dolomite reservoir in Leikoupo Formation in Zhongba Area CrossRef Full Text | Google Scholar Characteristics and formation conditions of carbonate reservoir in Leikoupo 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unconventional marl reservoir: a case study of the Member 1 of Maokou Formation in Hechuan-Tongnan Area CrossRef Full Text | Google Scholar Conglomerate petrology characterization using high-definition borehole electrical images in the Upper Urho Formation at well JL42 CrossRef Full Text | Google Scholar Gas⁃bearing property prediction of Leikoupo Formation in the northwest Sichuan Basin based on the theory of two⁃phase media CrossRef Full Text | Google Scholar Generating porosity spectrum of carbonate reservoirs using ultrasonic imaging log CrossRef Full Text | Google Scholar A new unconventional gas reservoir type: source-reservoir integrated carbonate gas reservoir from evaporated lagoon facies in Lei32 sub-member in Central Sichuan Basin CrossRef Full Text | Google Scholar Application of hyperspectral scanning in mineral composition analysis of carbonate rocks doi:10.15898/j.cnki.11-2131/td.202112100200 CrossRef Full Text | Google Scholar Direction of gas exploration in the middle Triassic Leikoupo Formation of the Sichuan Basin CrossRef Full Text | Google Scholar Application of Fullbore formation Microimager (FMI) to study of glutenite sedimentary structures in Jiyang Depression Google Scholar Wu S and Yang S (2024) Utilizing logs to identify complex lithology of tight marl reservoir in the Leikoupo Formation 32 Submember (T2l32) of the Sichuan Basin Received: 02 April 2024; Accepted: 02 May 2024;Published: 20 May 2024 Copyright © 2024 Yuan, Wu, Xin, Zhang, Wu and Yang. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use *Correspondence: Zhiwei Wu, MjAyMjcxMDM2N0B5YW5ndHpldS5lZHUuY24= and they still hold up all these years later Not content with releasing PS1 and PS2 classics NIS have truly outdone themselves with Rhapsody: Marl Kingdom Chronicles which includes two titles in the Rhapsody series I didn’t even know existed The original Rhapsody was released on the PS1 but it also released on the DS and as part of Prinny Presents Volume 3 you adventured across the land and used your magical powers to control puppets that helped you in combat It was a fairly simple game with a cute story and adorable characters In Rhapsody II: Ballad of the Little Princess you play as Cornet’s daughter Kururu who is getting old enough to want to escape the castle she grew up in and find her prince charming After a life of luxury and pampering in the castle Kururu doesn’t really understand that she can’t just do whatever she wants on her adventure which gets her into some wacky and generally amusing situations Don’t go in expecting an epic story full of emotional moments and tragic deaths As well as attacking with your party members themselves you can also summon any puppets they have equipped to fire off an attack or heal these cuddly helpers demand a bit of cash to come and help you deal with any smiling mushrooms or slimes that want to beat you up The best part about equipping puppets though is that just by placing them on a character they’ll give you some big ole stat boosts so even if you’re strapped for cash gathering and levelling up these adorable allies is well worth doing the best thing about Rhapsody: Marl Kingdom Chronicles is the music These games have a joyous and catchy soundtrack full of la la las and light-hearted melodies The very best moments of the game are when the characters unexpectedly burst into song which although sung in Japanese have subtitles to let you know that our lovely protagonist is belting out a ballad about finding her one true love Because the games included in Rhapsody: Marl Kingdom Chronicles haven’t been released in the west before it’d be totally reasonable to expect some subtitles for us English speakers and not a lot more NIS decided that wouldn’t be good enough though and added English voice acting to these old PS1 games and just shows that NIS are willing to go above and beyond to make their classic titles available in the best possible form for their fans the games also have some spruced up text to make reading all that dialogue a little more palatable Although the rest of the visuals are still made up of the same lower resolution sprites from back in the day it’s amazing how well they hold up in 2023 Sure when the camera zooms out a bit the environments are a bit blurry and backdrops are reused sometimes but not a lot of PS1 games are as pretty as Rhapsody it’s hard to ask people to spend their time and money on a collection of games that just aren’t on that level The fact that Rhapsody: Marl Kingdom Chronicles exists makes me extremely happy because niche titles like the ones in this collection are so often lost to history Admittedly compared to modern turn-based RPGs they do feel a little lacking but the charm of the musical theme and silly characters is undeniable If you’re interested in older Nippon Ichi games or enjoyed the first Rhapsody game in Prinny Presents Volume 3 Rhapsody: Marl Kingdom Chronicles might struggle to stand up to modern RPGs but it's a thoroughly charming bit of gaming history Brad Schloesser has been named the next Executive Director of the Minnesota Agriculture and Rural Leadership Program (MARL) at SMSU.  Brad is coming to MARL from South Central College in North Mankato & Faribault where he has served as the Dean of Agriculture and served as the first director of the Minnesota State Southern Agricultural Center of Excellence Brad taught post-secondary agriculture for two decades.  Brad has been a leader in agricultural education across the state for over 30 years and became a MARL alumnus in Class XI in June 2022.  In addition to his time at South Central College Brad has served as an Agriculture and Rural leader in many ways.  Most notably as a development team member for GreenSeam a leader with the Minnesota Association of Agricultural Educators and a developer and program manager of the National CASE Ag Science Curriculum.  Brad holds a Master of Science in Animal Science from Montana State University in Bozeman Montana as well as a Bachelor of Science in Agricultural Education from the University of Minnesota Brad will be concluding the fall semester as the Dean of Agriculture at South Central College (SCC) “The MARL Executive Director role is one that I have prepared for a lifetime to humbly serve The experiences gained as a MARL class member and internationally all will be cultivated in the rich future ahead,” said Brad “I am excited for the future and hopeful for the ability to serve those who have benefited from this program I look forward to this with a growth mindset and am optimistic this new endeavor will be fulfilling and exciting as we work at strengthening leaders past Brad brings to MARL three decades of supporting and building partnerships with students His work has been primarily centered around the learning and development of agricultural professions and consumers He has also been a lifelong advocate for FFA “I’m excited about this announcement because Brad brings to the table an untethered enthusiasm for MARL,” said Mark Enninga president of the MARL Board and Class IX alumnus “Brad also brings the ability to recruit and retain students and other stakeholders as well as his familiarity with the MARL program and his future colleagues.” reside near Saint Peter on a rural acreage and some Minnesota River Valley lands.  Their two adult daughters are married and are involved in agriculture They have eight grandchildren and are aware of the blessings of family “I am very excited to be working with Brad as the MARL Program begins a new chapter under his leadership,” said Nathan Polfliet Brad will begin his role as the MARL Executive Director on December 19 after the current semester at South Central College is complete and the new MARL Class XII is beginning their journey The MARL program is a dynamic leadership development program for active and engaged adult agricultural and rural leaders in Minnesota a class of up to 30 participants is selected through a rigorous application process Each class has roughly two-thirds of participants involved in production agriculture and organization professionals from across rural Minnesota agriculture To learn more about the MARL Program, visit the website: www.MARLprogram.org Volume 18 - 2024 | https://doi.org/10.3389/fnbot.2024.1364587 Multiagent Reinforcement Learning (MARL) has been well adopted due to its exceptional ability to solve multiagent decision-making problems knowledge transfer algorithms have been developed among which experience-sharing-based and action-advising-based transfer strategies share the mainstream although there exist many successful applications of both strategies For the long-developed action-advising-based methods (namely KT-AA short for knowledge transfer based on action advising) their data efficiency and scalability are not satisfactory As for the newly proposed experience-sharing-based knowledge transfer methods (KT-ES) although the shortcomings of KT-AA have been partially overcome they are incompetent to correct specific bad decisions in the later learning stage To leverage the superiority of both KT-AA and KT-ES expecting better data efficiency from KT-ES to enhance the policy to a basic level as soon as possible we focus on correcting specific errors made by the basic policy trying to use KT-AA methods to further improve the performance Simulations demonstrate that the proposed KT-Hybrid outperforms well-received action-advising- and experience-sharing-based methods introducing a kind of hybrid trigger condition by considering both the advisors' monitoring and the advisees' requirements By modeling the learning agents as memetic automatons eTL provides two metrics to evaluate whether an agent has learned a better policy than the others in the training process forming a dynamic indicator as the trigger condition to provide action advice an important operator in memetic computing Recently, Experience-Sharing-based Knowledge Transfer (KT-ES) has been proposed to tackle these problems. Wang et al. (2022) extended the concept of memetic knowledge transfer MeTL-ES proposed to share specific experiences This mechanism converts the bi-directional information flow in each transfer to a one-way manner which solves the scalability issue by nature MeTL-ES employs a new idea in designing the trigger condition Rather than selecting experiences with higher rewards or Q values it shares experiences with stochastic rules which matches the need for exploration in RL When the performance is enhanced to a certain level and the exploration is roughly enough; MeTL-ES tends to indicate the value of an experience via Q values Only experiences with higher possible outcomes will get transferred we can observe a rapid rise in performance in the early stage which benefits from the sufficient exploration brought by MeTL-ES KT-ES methods such as MeTL-ES lack the focus on the later stage indicating that KT-AA and KT-ES have complementary features this study proposes a Hybrid Knowledge Transfer method by binding the advantage of KT-AA and KT-ES expecting to promote the learning performance of the randomly initialized agents in the whole process the contributions of this study are 3-fold: This study discusses the scopes of application of KT-AA and KT-ES and presents a novel two-phase knowledge transfer framework to enhance the learning speed of MARL accordingly; Based on the unique features of the framework along with the corresponding trigger conditions to balance exploration and exploitation; Building on the well-received Minefield Navigation Tasks empirical studies in several typical scenarios are provided in this study indicating that the proposed KT-Hybrid outperforms popular KT-AA and KT-ES algorithms This section introduces some basic concepts and knowledge relevant to this study RL is an effective way to solve decision-making problems that can be modeled as Markov Decision Processes (MDP), and the entity that makes decisions to achieve certain tasks in a given environment is called an agent (Barto et al., 1989; Sutton and Barto, 2018) in which S→ℝS denotes the S-dimensional state space of the environment A={a1,a2,⋯,aK}→ℝK represents the K-dimensional action space of the agent T(s,a,s′):S×A×S→[0,1] works as the state transition function providing the probability that the current state s will transfer to s′ when the agent takes action a R(s,a):S×A→ℝ is the reward function The discount factor γ defines how a future reward will be discounted the experience of an agent can be defined as 〈s in which s denotes the state of the environment a represents the action that the agent takes r shows the reward that the agent can earn from the environment when implying action a and s′ informs the resultant environment state that corresponds to s and a the goal of an RL agent is to learn a policy π:S×A→[0,1] to conduct sequential decision-making processes in the MDP the policy will gradually converge to an optimal policy that can maximize the state value of the initial state The state-value function can be given as follows: in which st and rt imply the state and reward at time t Q-learning is one of the most popular RL algorithms (Watkins and Dayan, 1992) which learns to estimate the Q-value function given as follows: the update rule can be written as follows: in which y=r+γmaxa′Q(s′,a′) denotes the target Since Deep Neural Networks (DNN) have been developed greatly in the past decade, Mnih et al. (2013) and Mnih et al. (2015) proposed Deep Q-Network (DQN) the loss function of the neural network in the learning process can be given as follows: which is designed to break the correlations of the data Another part that can do the same is the introduction of the target network the target network is a copy of the policy network whose parameters are updated intermittently Denoting the parameters of the target network as θ− the target value can be calculated as follows: When the number of entities that need to make decisions extends from one to several, the underlying model will be extended from MDP to Stochastic Games (SG) (Shapley, 1953) An SG can be described by the tuple of 〈n,S,A,T,R,γ〉 in which n is the number of agents and S represents the state of the environment A:A1,A2,⋯,An denotes the joint action space where Ai gives the action space of agent i we can define the action of agent i as ai∈Ai and the joint action a∈A as the joint action of all the agents we can write the state transition function T as T(s,a,s′):S×A×S→[0,1] the agents cannot have access to the global state of the environment they will have different observation functions the tuple of an SG can be extended to 〈n,S,O,O,A,T,R,γ〉 in which the added O:O1×O2,⋯,On describes the joint observation space of the agents and O:O1×O2⋯ × On gives the observation functions we only consider the commonly used homogeneous multi-agent systems in which the agents share the same observation function O we adopt I-DQN as the basic learning algorithm in this study Knowledge transfer mechanisms aim to leverage insights gained by one agent to accelerate learning or improve performance for another agent This can be particularly beneficial in MARL since the learning agents are able to share various types of useful information agents using KT-ES methods share personal experiences in a one-way manner the experiences are defined by the state transitions together with variables used to calculate the sharing trigger conditions The stochastic sharing without consideration of specific states leads to unfamiliar situations for which exploration may emerge it is clear that both KT-AA and KT-ES can enhance learning performance we will introduce a novel knowledge transfer method that combines the strengths of KT-AA and KT-ES to enhance the learning performance of independent MARL systems further This section introduces the overall architecture of the proposed KT-Hybrid algorithm along with the design details answering the questions of what to transfer Recalling the goal that we require the knowledge transfer to achieve we need the agents in MARL systems to learn as fast as possible at which period the agents will form basic-level policies that can roughly obtain a satisfactory performance it is not ideal to put too much extra computational load on the agents at this early learning stage to avoid possible obstacles to large-scale MARL it would be better to adopt knowledge transfer methods with guaranteed scalability These discussions make the KT-ES a great solution for the MARL problems KT-AA focuses on every single decision-making performance of an agent at the cost of scalability KT-AA needs bidirectional interactive communication rather than unidirectional broadcast-like communication in KT-ES this brings about the unique advantage of KT-AA and KT-AA can help the agents in specific decision-making steps every possible action of each agent has some possibility of getting double-checked by other agents helping to prevent bad decisions in specific states This feature of KT-AA indicates that although it may be inefficient in the early learning stage it has the potential to further enhance the policies that are roughly trained KT-ES and KT-AA exhibit distinct advantages across different learning stages suggesting the potential for improved learning performance through their combination Building on the above discussions, the goal of this study is to design hybridization of KT-ES and KT-AA, KT-Hybrid, trying to make full use of their complementary features. Overall, the KT-Hybrid follows a two-phase structure, as shown in Figure 1 Robots in different backgrounds represent different learning agents purple waves show the shared experience in the Igniting Phase black arrows depict the self-learning process of the agents and the blue and orange arrows are the transferred state and action in the Boosting Phase the green background shows the early learning stage and the orange shows the later learning stage These two stages are divided with a blurred line indicating that the shift timing should be selected by balancing the exploration and exploitation of these two stages the first phase is called the Igniting Phase which aims to rapidly learn a moderate-level policy in the early stage we design experience-sharing-based knowledge transfer mechanisms in the Igniting Phase leveraging the benefits of KT-ES in terms of fast learning speed and high data efficiency to provide the users with workable policies as soon as possible While for the learning process in the late stage the Boosting Phase takes over to further boost the policy to a higher level with more communication effort the requirement of the user is converted from getting workable policies to tuning the policies for better performance we need to follow the principles of the action-advising-based knowledge transfer approaches in the Boosting Phase expecting to obtain better performance even with a higher load Since the primary goal of knowledge transfer is to promote learning speed it is unacceptable for the KT-Hybrid if the transfer scheme is of high complexity order which may lead to significant computational costs it is obvious that due to the complex mechanism we will detail the format of knowledge in the two phases in Section 3.2 introduce a novel trigger condition to balance the two phases in Section 3.3 and design the learning scheme accordingly in Section 3.4 This subsection will introduce what type of knowledge is transferred in KT-Hybrid To meet the two-phase architecture of KT-Hybrid we need to design the form of knowledge separately For the Igniting Phase, agents are required to share implicit knowledge that works as ingredients in the learning process, i.e., experiences (Wang et al., 2022) this agent will observe the state of the environment and obtain its own observation at this time oti agent i makes a decision to take action ati according to oti and its current policy πti the state of the environment s will transit to a new state s′ and agent i will get an updated state observation agent i will also get the reward signal rti from the environment after a complete state (observation) transition the experience of agent i at time t can be formulated as follows: agent i will assess the quality of Eti; once Eti is suitable for sharing it will be broadcast as a knowledge package Kti by agent i to the other agents for further learning the knowledge at time t in the Igniting Phase In the knowledge shown in Equation 8 pIti denotes the probability for agent i to share the current experience in the Igniting Phase Detailed description and definition of pIti will be provided in Section 3.3 the way how KT-Hybrid uses the shared knowledge KtI for learning will be described in Section 3.4 The benefits of defining the state (observation) transition as the carrier of knowledge are threefold sharing transitions that an agent has just experienced does not need any extra computation or memory storage which means that the agents can learn faster with no extra loads since the broadcasting of experiences is a one-way communication the overall communication load will only increase linearly the state transition is commonly used as experience in RL which makes KT-Hybrid a general knowledge transfer method for a wide range of MARL algorithms the agents will have moderate-level policies to handle the task in the environment it is time for the agents to transfer explicit knowledge to get action advice for observation oti at time t it will query the other agents with the observation oti other agents will provide actions according to their own policies it generates actions atij according to πtj and oti in which atij represents the action generated by agent j to solve the observation of agent i at time t it will receive a collection containing advice from all the others defining the probability of triggering the action advising from agent j for agent i as pBtij all the advice for agent i at time t can be defined as follows: the knowledge at time t in the Boosting Phase With the action advice from the other agents the focal agent can avoid some inappropriate decisions made by the moderate-level policy transferring action-based explicit knowledge can further improve the policy in the boosting phase Since the primary goal of KT-Hybrid for learning-from-scratch settings is to promote learning performance in the whole process it is important to assess whether the knowledge should be transferred the trigger conditions that enable knowledge transfer in the literature have the goal of transferring knowledge that can result in better task performance we have to distinguish the different purposes between knowledge transfer in the multi-agent learning process and action demonstration in the process of task execution the goal of knowledge transfer should be to promote the learning performance rather than to enhance the correctness of some specific actions which is especially true for the scenarios when all the agents learn simultaneously it is necessary to re-consider what kind of knowledge is more beneficial to different learning phases in KT-Hybrid The Q value is a widely adopted metric to design trigger conditions (Silva and Costa, 2019) all of the agents are in the early learning stage conventional metrics such as Q values are not reliable since the networks have not been fully trained according to the explore–exploit balance RL agents at this stage need to sufficiently explore the environment the Q values calculated by the networks will be more accurate and reliable the probability of triggering knowledge transfer for any agent i at time t is defined as pti Q̄t-i represents the mean value of the latest Q values received from the other agents in which N-1 denotes the agents in the MARL system without agent i. Meanwhile, f(Qti,τ) in Equation 12 defines a scaling function inspired by the Sigmoid function in which τ represents the learning steps that agent i has experienced the scaling function can be calculated as follows: where a and b are tuning hyper-parameters. Substituting Equations 12, 13 into Equation 11 when agent i has experienced little training the sharing of experiences will be triggered as much as possible the agents will tend to share experiences with higher Q values This matches our expectations for the balance between exploration and exploitation However, we should note that due to the trigger condition in the Igniting Phase (Equation 11) does not consider any specific observations the agents can only get moderate-level policies from the overall perspective the agents will have different learning trajectories after the independent learning in the Igniting Phase indicating they will be proficient in different states building on the policies learned in the Igniting Phase the agents need to further learn from the others' expertise in the Boosting Phase Inspired by Hou et al. (2021) we consider two metrics to evaluate the necessity of taking advice the value of which counts the number of successful episodes that agent i has experienced The other is the self-significance hi=Qti/max(Q1i,⋯,Qti) which evaluates the significance of an action advice to the advisor will only be qualified for agent i to choose when satisfying the following condition: By the condition shown in Equation 14 only advice provided by agents with better overall performance that may have higher potential returns will be considered since an agent is allowed to take only one action at a time we need to further design a merging module to resolve the conflicts among the qualified actions from different peers Inspired by the multi-objective evolutionary algorithms a ranking score Rj for each qualified action aij can be given as follows: in which l^j=lj/max(l1,⋯,ln) is the regulated success counts we can finally choose the action with the highest Rj as the final advice among the qualified candidates in the Boosting Phase the extra computational load brought by the trigger conditions of KT-Hybrid is tolerable Another critical issue is how to determine the timing to shift the learning phase from the Igniting Phase to the Boosting Phase which means we need a metric to determine whether the learning process is in the early or later stage There are several potential principles in designing this shift scheme including making the agents keep transferring knowledge in the whole learning process preserving a longer Igniting Phase for less communicational cost or letting the Boosting Phase intervene as early as possible for more efficient transfer we take a straightforward shifting scheme by setting a fixed learning episode threshold E to divide the early and later learning stages The learning process will be taken as the early learning stage before E episodes have been experienced in which period the Igniting Phase will be triggered the Boost Phase will be used for the following learning process The sensitivity of E will be tested later in Section 4 while the design of shifting schemes holds promise for exploring the potential of KT-Hybrid delving into this aspect is currently beyond the scope of this study we omit this part and take the corresponding computational load as a constant Ct Assuming there are n agents in the MARL system each of which conducts one round of both decision-making and training at each time step on average the total amount of computation of the system can be formulated as follows: in which cI and cB are the total computational load of the Igniting Phase and the Boosting Phase β is a binary indicator showcasing the current phase When the number of experienced episodes is less than E indicating the Igniting Phase is triggered; on the contrary we have β = 0 in the Boosting Phase Denoting the computational load of one decision-making process of each agent as cf and one backpropagation as cb the total computational load of the system in a step can be written as For the Boosting Phase in which KT-Hybrid performs action advising assuming the probability for each agent to ask for advice is pask and a probability pans for agents received the inquiries to provide advice to the advisees the total computational load of n learning agents can be given as follows: Substituting Equations 17, 18 into Equation 16 the full computational load of the n-agent system in one step can be given as follows: the time complexity of the proposed KT-Hybrid is O(n2) It is also noted that although the proposed KT-Hybrid shares the same time complexity with KT-AA methods the computational cost of KT-Hybrid is less due to the Igniting Phase Having detailed the format and transfer timing of the knowledge this subsection will introduce how to integrate the transferred knowledge into the learning process Non-stationarity is one of the most important issues to handle in the independent MARL processes. To prevent the learning performance from being affected by the non-stationarity brought by the simultaneous learning of multiple agents, a common solution is to disable the experience replay buffer (Palmer et al., 2018) techniques such as synchronized learning have also been developed these approaches can only reduce the influence of non-stationarity to some extent rather than fully remove it we ignore the non-stationarity issue and learn with both the shared experiences both of which are stored in a replay buffer D The primary reason for neglecting the non-stationarity in this phase is to ensure data efficiency for better exploration of the environment which helps to promote the policies as expected for the Igniting Phase since the policies of the agents vary widely from random ones in the Igniting Phase it should be difficult to significantly reduce the effect of non-stationarity the loss function for learning in the Igniting Phase can be written as follows: the policies grow to a relatively stable level which differs a lot from previous policies it is important to avoid the non-stationarity brought by outdated experiences we only train the agents with the latest transitions in the Boosting Phase This section provides simulation results to validate the effectiveness of the proposed KT-Hybrid In this section, we set the map of MNT as 16 × 16. The network of each learning agent is a fully connected two-layer multi-layer perceptron with 36 neurons in each layer. The learning rate is set to be 0.5. ϵ-greedy is utilized in the training process, the value of which anneals linearly from 0.5 to 0.005. Hyper-parameters a and b in Equation 13 are set to 5 and 0.001 The agents will be trained for 100,000 episodes and the maximum length of each episode in MNT is set to 30 steps the switch between the Igniting Phase and the Boosting Phase occurs after 10,000 episodes The second testing environment is the Half Field Offense (HFO) environment (Hausknecht et al., 2016), which was used as the testbed for AdHocVisit and AdHocTD (Silva et al., 2017) we compare the performance of KT-Hybrid with AdHocVisit and AdHocTD for fairness Figure 3 depicts a snapshot of the HFO environment, including three agents learning from scratch, trying to score goals. Moreover, there is a goalkeeper with the Helios policy, which is from the 2012 RoboCup 2D champion team. To achieve fair comparison, we use the same environmental setting, learning parameters of AdHocTD and AdHocVisit, and the Helios policy with the study by Silva et al. (2017) the learning process shifts from the Igniting Phase to the Boosting Phase after 500 episodes we first provide a comparison of the results in the MNT environment with 3 agents and 5 mines to validate the advantage of the proposed KT-Hybrid All the results are generated by 30 independent runs Figure 4 shows the learning performance of the proposed KT-Hybrid and the other baseline methods The lines plot how the average success rate changes in the learning process while the shadows depict one standard deviation It is obvious that the proposed KT-Hybrid outperforms the other methods in the success rate of the task If we compare the results of KT-Hybrid with those of MeTL-ES we will notice that although they both share a fast promotion in the learning process (Igniting Phase for KT-Hybrid) the line of MeTL-ES drops slightly from the best performance the success rate keeps going up in the Boosting Phase This difference matches our expectations when designing KT-Hybrid in Section 3 indicating that the proposed KT-Hybrid can achieve better performance by integrating experience-sharing-based and action-advising-based knowledge transfer approaches in the two-phase structure focusing on specific decision-making processes of all the agents This enhances communication around the KT-AA level Comparision of the number of communication on MNT This results in a higher starting point for the Boosting Phase than agents with eTL at the same stage agents with KT-Hybrid will need less advice than eTL to accomplish the task This negative correlation between the number of communications and the success rate also indicates the rationality of the trigger conditions provided in Section 3.3 these results also indicate the superiority of using KT-Hybrid in real-world applications the users can get moderate-level policies in a very short time with limited communication in the Igniting Phase which means that the agents can form a basic ability to solve certain tasks the users can decide how much extra training is needed in the Boosting Phase via systematical consideration of the performance and the training cost To further validate the superiority of KT-Hybrid we also provide the comparison results of KT-Hybrid with AdHocTD and AdHocVisit on the HFO platform Figure 6 demonstrates the learning performance of the proposed KT-Hybrid with the other three baselines The lines show the average rate of goal with learning proceeds our proposed KT-Hybrid still outperforms the baselines we further compare the learning results with the aforementioned knowledge transfer algorithms in different experimental scenarios Figure 7 compares the success rates and the number of communications in different scenarios the results are generated in MNT tasks with (a) & (b): 3 agents and 5 mines (3a5m) (c) & (d): 5 agents and 10 mines (5a10m) (e) & (f) 10 agents and 5 mines (10a5m) and (g) & (h): 15 agents and 3 mines (15a3m) It is noted that as the number of agents grows These trends are reasonable because as the scale grows the number of communications is enlarged since there are more agents involved in the knowledge transfer the superiority of KT-Hybrid remains in these scenarios and the curve trends of KT-Hybrid are aligned with the results and discussions in Section 4.2 Performance comparison in different scenarios Table 1 compares the average success rate of the different algorithms in different scenarios which also indicates the advantage of KT-Hybrid Average success rate of the different knowledge transfer approaches in different scenarios To further validate the proposed KT-Hybrid we have also added experiments on different settings of the phase shifting time we can find that the KT-Hybrid is not very sensitive to the phase-shifting time E but we still need to conduct more research on how to choose the phase-shifting time in the future Performance comparison of different phase shifting time This study proposed a novel knowledge transfer method for independent MARL The proposed KT-Hybrid integrates the widely adopted KT-AA and the recently proposed KT-ES into a two-phase architecture agents with KT-Hybrid conduct the Igniting Phase trying to leverage the high data efficiency of KT-ES to achieve fast promotion of the decision-making ability via experience sharing based on the moderate-level policies obtained by the Igniting Phase the following Boosting Phase tries to further enhance the performance via transferring actions Empirical studies on several MNT scenarios show that the performance of the proposed KT-Hybrid matches our expectations in design and outperforms the baselines A primary concern lies in the manually adjusted shift timing between the Igniting Phase and the Boosting Phase which necessitates reliance on the user's domain expertise a more comprehensive investigation on the influence of hyperparameters through theoretical analysis is desired Such an approach can offer insights into the underlying mechanisms governing the performance of KT-Hybrid the exploration of automated tuning methods leveraging cutting-edge intelligent decision-making techniques such as evolutionary algorithms holds promise for enhancing the efficacy of KT-Hybrid the development of a data-driven metric for evaluating the optimal phase selection within the algorithm is also promising could further enhance the adaptability and robustness of KT-Hybrid The raw data supporting the conclusions of this article will be provided on request DL: Writing – review & editing JG: Writing – review & editing The author(s) declare financial support was received for the research This research was funded by the National Key Research and Development Program of China grant number 2021YFC2803003 “Interactive teaching strategies for agent training,” in Proceedings of the 25th International Joint Conference on Artificial Intelligence (New York Google Scholar Google Scholar Reinforcement learning for selective key applications in power systems: recent 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with deep reinforcement learning,” in Proceedings of the 34th AAAI Conference on Artificial Intelligence (New York Li D and Gao J (2024) Hybrid knowledge transfer for MARL based on action advising and experience sharing Received: 02 January 2024; Accepted: 10 April 2024; Published: 07 May 2024 Copyright © 2024 Liu, Li and Gao. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) *Correspondence: Dongqi Li, MzA1NjA3ODk3QHFxLmNvbQ== OPINION: NJ’s ‘marl’ pits yield dinosaur wondersAsburyParkEver wonder how New Jersey towns like Marlton and Marlboro got their names Look no further than “marl,” a soil also known as greensand Marl deposits date to the time when the southeastern half of this state we’re in was the sea floor and greensand was deposited in coastal bays and freshwater river mouths The marl contains fossils of ancient shelled invertebrates and freshwater and marine forms of every vertebrate group — fish Colonial-era farmers discovered that marl — which contains clay and calcium carbonate — made great fertilizer Many marl pits were dug in the narrow geographic band now known as the Inner Coastal Plain Greensand was sold to farmers all over New Jersey and beyond spotted gigantic bones in a sand pit on his property fossil hobbyist William Parker Foulke heard about the bones while vacationing nearby They excavated the bones of an animal larger than an elephant with structural features of both a lizard and a bird The fossilized bones were the world’s first nearly complete dinosaur skeleton The dinosaur died along the shallow coastline during the Cretaceous period 65 to 145 million years ago and sank to the bottom where its skeleton fossilized in the greensand The creature was named Hadrosaurus foulkii after Foulke and Haddonfield and was the first mounted dinosaur ever to be displayed to the public when it was put on exhibit at the Academy of Natural Sciences in Philadelphia in 1868 Nearly 160 years after the dinosaur discovery made Haddonfield the birthplace of American paleontology “New Jersey is a great place to be if you’re a paleontologist,” says David Parris paleontologist and head curator of natural history at the New Jersey State Museum in Trenton The state’s most productive fossil region is the Inner Coastal Plain which runs from Raritan Bay to the upper reaches of the Delaware Bay in Salem County During the Cretaceous period — when New Jersey was located much closer to the equator the Earth was warmer and sea levels higher — the Atlantic coastline was located there the sediments of the Inner Coastal Plain contain fossils of both sea creatures like mosasaurs and giant crocodiles and land creatures that lived in swamps on the edge of the continent Two Inner Coastal Plain sites where land has been permanently preserved are especially good for finding fossils The first is within Monmouth County’s Historic Walnford Park preserved with the help of New Jersey Conservation Foundation in the 1970s is yielding thousands of fossils of all sizes all being studied at the New Jersey State Museum The second is the former Inversand Quarry in Mantua Township where mosasaurs — ancient sea lizards resembling Komodo dragons — were excavated Rowan University purchased the quarry in 2016 It is now called the Jean and Ric Edelman Fossil Park and is available to Rowan students as well as schools and individuals attending “Community Dig” days The former quarry must be continually pumped to keep out water but the marl there is so soft that paleontologists can dig with a garden trowel rather than having to chip through rock the site where “Haddy” the hadrosaurus was discovered is no longer a viable dig site its exact location was lost until 1984 when a local Boy Scout named Chris Brees used old maps and Joseph Leidy’s descriptions to rediscover it the site is marked with a plaque commemorating its amazing history If you want to learn more about New Jersey’s Inner Coastal Plain and the fossils discovered there take time to visit the New Jersey State Museum Among the exhibits are a full-size hadrosaurus made from casts of the original bones excavated in Haddonfield in 1858 and a giant crocodile from Burlington County just found in the last couple of years You can even watch as scientists carefully remove this fossil crocodile from the rock in which it is embedded The original Haddonfield dinosaur is kept at the Academy of Natural Sciences and is too fragile to be displayed Find out more about the NJ State museum exhibit at http://www.nj.gov/state/museum/dos_museum_exhibit-written-rocks.html go to the Academy of Natural Sciences website at http://ansp.org/explore/online-exhibits/dinosaurs/ And to learn more about preserving New Jersey’s land and natural resources visit the New Jersey Conservation Foundation website at www.njconservation.org or contact me at info@njconservation.org Byers is executive director of the New Jersey Conservation Foundation.