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Baseflow And Water Resilience Variability In Two Water Management Units In Southeastern Brazil, Lucas Vituri Santarosa, Didier Gastmans, Troy E. Gilmore, Jan Boll, Sebastian Balbin Betancur, Vitor Fidelis Monteiro Gonçalves 2022 São Paulo State University

Baseflow And Water Resilience Variability In Two Water Management Units In Southeastern Brazil, Lucas Vituri Santarosa, Didier Gastmans, Troy E. Gilmore, Jan Boll, Sebastian Balbin Betancur, Vitor Fidelis Monteiro Gonçalves

Conservation and Survey Division

Changes in climate and water demand in densely populated regions increasingly affect hydrological systems, and, in turn, impact socioeconomic conditions. In this case study, we identify how the hydrogeological frameworks of two water resource management units, Tietê-Jacaré (TJ) and Piracicaba-Capivari-Jundiaí (PCJ) in Sao Paulo state (Brazil), control the baseflow processes and resilience in the face of streamflow fluctuations in response to anthropogenic activities and climate variation. The results reveal between 40% and 75% contributions of baseflow to total streamflow in basins overlying crystalline and sedimentary aquifers. The basins in PCJ which mostly overly crystalline aquifers, have shorter water residence times …


Male Mastodon Landscape Use Changed With Maturation (Late Pleistocene, North America), Joshua H. Miller, Daniel C. Fisher, Brooke E. Crowley, Ross Secord, Bledar A. Konomi 2022 University of Cincinnati

Male Mastodon Landscape Use Changed With Maturation (Late Pleistocene, North America), Joshua H. Miller, Daniel C. Fisher, Brooke E. Crowley, Ross Secord, Bledar A. Konomi

Department of Earth and Atmospheric Sciences: Faculty Publications

Under harsh Pleistocene climates, migration and other forms of seasonally patterned landscape use were likely critical for reproductive success of mastodons (Mammut americanum) and other megafauna. However, little is known about how their geographic ranges and mobility fluctuated seasonally or changed with sexual maturity. We used a spatially explicit movement model that coupled strontium and oxygen isotopes from two serially sampled intervals (5+ adolescent years and 3+ adult years) in a male mastodon tusk to test for changes in landscape use associated with maturation and reproductive phenology. The mastodon’s early adolescent home range was geographically restricted, with no evidence of …


The Revised Systematics And Paleoecology Of The Devonian Stemless Crinoid Genus Edriocrinus Hall, 1858, Catherine E. Herbert 2022 University of Kentucky

The Revised Systematics And Paleoecology Of The Devonian Stemless Crinoid Genus Edriocrinus Hall, 1858, Catherine E. Herbert

Theses and Dissertations--Earth and Environmental Sciences

New morphological observations of Edriocrinus Hall, 1858, enable a modern, holistic view of this unusual crinoid genus, previously included in the Superorder Flexibilia (Zittel, 1895) Wright et al., 2017. Re-analysis of Edriocrinus suggests that the genus should now be assigned to the Order ‘Dendrocrinida’ within the Magnorder Eucladida Wright, 2017 based on the five infrabasals, single radianal in the cup, absent anal sac, and non-pinnulate arms with rectangular uniserial brachials. Moreover, examination of the slight variations separating the current 14 Edriocrinus species indicates that these “species” are likely ecophenotypes. The current Edriocrinus species are revised based on firmly bound calyx …


Microfabric Analysis Of Mid-Pliocene Amundsen Sea Interglacial Sediments Demonstrates A Link Between Iceberg Melt And Diatom Productivity (Iodp Exp. 379), Heather Leanne Furlong 2022 Northern Illinois University

Microfabric Analysis Of Mid-Pliocene Amundsen Sea Interglacial Sediments Demonstrates A Link Between Iceberg Melt And Diatom Productivity (Iodp Exp. 379), Heather Leanne Furlong

Graduate Research Theses & Dissertations

Anthropogenically induced climate change in the polar regions has rapidly become an emergent global issue, especially for low-lying coastal communities, which are most affected by sea-level rise. The future of the West Antarctic Ice Sheet (WAIS) is of significant concern due to its history of instability and retreat, especially in light of the observed ongoing changes. Establishing rates of retreat is critical to forecasting future behavior of the WAIS, and previous studies have been unable to establish rates of ice sheet collapse in part because Antarctic continental shelf records are impacted by erosional hiatuses. In 2019, International Ocean Discovery Program …


The Kanarra Fold-Thrust System -- The Leading Edge Of The Sevier Fold-Thrust Belt, Southwest Utah, William Joseph Michael Chandonia 2022 Missouri University of Science and Technology

The Kanarra Fold-Thrust System -- The Leading Edge Of The Sevier Fold-Thrust Belt, Southwest Utah, William Joseph Michael Chandonia

Doctoral Dissertations

“The Jurassic to Eocene Sevier fold-thrust belt is the subject of continued scientific curiosity in tectonics, stratigraphy, and industry. Understanding its development in southwest Utah is hindered in part due to the multiple origins proposed for the Kanarra anticline, a major leading edge structure -- a drag fold along the Hurricane fault, Laramide monocline, Sevier fault propagation fold, or a combination of these -- which have confused its tectonic significance and regional context. This confusion results from the structural complexity of its exposed eastern limb, as well as displacement and burial of its crest and western limb beneath Neogene sediments …


The Impact Of Sampling Methodology On Soil Bulk Density Measurement By The Clod Method, Aldi J. Airori, Trinity Baker, Judith Turk 2022 University of Nebraska-Lincoln

The Impact Of Sampling Methodology On Soil Bulk Density Measurement By The Clod Method, Aldi J. Airori, Trinity Baker, Judith Turk

Conservation and Survey Division

The clod method is a widely used and accurate bulk density method. However, its use is limited to sampling from soil pits. This study was conducted to: 1) determine whether clods collected from cores provide similar bulk density measurements to those collected from soil pits and 2) evaluate the impact of various clod bulk density methods on carbon stock calculation. Clods were collected from soil pits, 5.1 cm soil cores, and 8.9 cm soil cores. Three-dimensional laser scanning was used to measure the volume of the soil clods before and after oven-drying and bulk density was calculated as the dry …


Model Of A Biotic Hard Substrate Community: Paleoecology Of Large Trepostome Bryozoans From The Upper Ordovician (Katian) Of The Cincinnati Region, Usa, Kate Runciman 2022 The College of Wooster

Model Of A Biotic Hard Substrate Community: Paleoecology Of Large Trepostome Bryozoans From The Upper Ordovician (Katian) Of The Cincinnati Region, Usa, Kate Runciman

Senior Independent Study Theses

The calcite skeletons of trepostome bryozoan colonies from the Upper Ordovician (Katian) of the Cincinnati region record the diverse interactions and growth responses these colonies experienced. Trepostome specimens from three Cincinnatian strata; the Bellevue Member, the Bull Fork Formation, and the Whitewater Formation, were studied within this project. These three strata were deposited in a shallow epicontinental sea environment that was located in the southern subtropics, approximately 20-23°S at the time of deposition. The focus of this project was the paleoecology of large trepostome bryozoans, which was studied by examining bryozoan growth patterns, trace fossils, and sedimentation. Microscopic examination of …


Stable Isotope Analysis Of A Platecarpus Tympaniticus (Squamata, Mosasauridae) With Actinocamax Sternbergi (Mollsuca, Belemnoidea) Reveals Possible Endothermic Thermoregulation, Mitchell Lukens 2022 Fort Hays State University

Stable Isotope Analysis Of A Platecarpus Tympaniticus (Squamata, Mosasauridae) With Actinocamax Sternbergi (Mollsuca, Belemnoidea) Reveals Possible Endothermic Thermoregulation, Mitchell Lukens

Master's Theses

Mosasaurs, ancient marine reptiles, dominated the late Cretaceous oceans. However, their ecological success is a contentious topic. Were they ectothermic, like their modern relatives the varanid lizards? Or endothermic like extant marine mammals? Stable isotopes can reveal temperature and physiological variances within skeletons, but do not differentiate between body temperature and ambient environmental temperature. A rare mosasaur specimen from the Smoky Hill Chalk of a partial, articulated Platecarpus tympaniticus with stomach contents of belemnites provides a possible direct temperature contrast between predator and prey. The belemnites, related to modern coleoids, are identified as Actinocamax sternbergi. These animals possessed body …


Unearthing The Effects Of European-American Settlement On A Northeast Ohio Kettle Lake Through Diatom Stratigraphy, Justine Paul A. Berina 2022 The College of Wooster

Unearthing The Effects Of European-American Settlement On A Northeast Ohio Kettle Lake Through Diatom Stratigraphy, Justine Paul A. Berina

Senior Independent Study Theses

Recently, wetland conservation has highlighted the necessity for assessing limnological changes following European-American settlement. A prior study at Brown's Lake (northeast Ohio) identified a stratigraphic sequence that shows an abrupt transition from organic-rich muds to several centimeters of a bright loess layer, then a recovery to organic-rich sediments near the top. Based on 210Pb dates, the loess deposition occurred before 1846 CE, when a growing population cleared trees and farmed intensively. Likewise, organics had recovered after 1950 CE, when people abandoned farmland and practiced conservation tillage. However, the effects of settlement on limnology are poorly known. Diatoms (microscopic algae; …


Examining Evolutionary Rate In Xiphosura, Samantha B. Ocon 2022 West Virginia University

Examining Evolutionary Rate In Xiphosura, Samantha B. Ocon

Graduate Theses, Dissertations, and Problem Reports

Horseshoe crabs, a group of aquatic chelicerate arthropods of the class Xiphosura, are strongly linked with the concept of “living fossils” – a term colloquially used to refer to clades that display a consistently low rate of morphological evolution through time. The concept of living fossils has been hotly debated, as it is considered to simplify or obscure millennia of evolutionary change. Recent methodological and computational advances in the paleobiological sciences have allowed for the investigation of these claims. Xiphosura are a model taxon for this type of investigative study because they exhibit a complex evolutionary history, despite their reputation …


The Naming Of Homo Bodoensis By Roksandic And Colleagues Does Not Resolve Issues Surrounding Middle Pleistocene Human Evolution, Eric Delson, Chris Stringer 2022 CUNY Lehman College

The Naming Of Homo Bodoensis By Roksandic And Colleagues Does Not Resolve Issues Surrounding Middle Pleistocene Human Evolution, Eric Delson, Chris Stringer

Publications and Research

Roksandic et al. (2022) proposed the new species name Homo bodoensis as a replacement name for Homo rhodesiensis Woodward, 1921, because they felt it was poorly and variably defined and was linked to sociopolitical baggage. However, the International Code of Zoological Nomenclature includes regulations on how and when such name changes are allowed, and Roksandic et al.'s arguments meet none of these requirements. It is not permitted to change a name solely because of variable (or erroneous) later use once it has been originally defined correctly, nor can a name be modified because it is offensive to one or more …


Strange Stones Of Skull Creek: Basalt Glacial Erratics And Omars In Eastern Nebraska, Robert M. Joeckel, Jesse T. Korus, Judith Turk, C. C. Arps, N. V. Arps, Leslie M. Howard 2022 University of Nebraska-Lincoln

Strange Stones Of Skull Creek: Basalt Glacial Erratics And Omars In Eastern Nebraska, Robert M. Joeckel, Jesse T. Korus, Judith Turk, C. C. Arps, N. V. Arps, Leslie M. Howard

Conservation and Survey Division

We describe unusual stream- reworked glacially transported rocks (erratics) from a locality 50 km east of the limit of all pre- Illinoian (pre- 190 ka) Pleistocene glaciations in the central USA. Almost all these erratics consist of the igneous rock basalt, and of those, the vast majority have at least one fl at, smooth face. Some have two or more such faces that meet at obtuse angles along one or more well- defi ned, straight edges. We attribute these features, as well as laminations, plumose marks, and other features, to columnar jointing in ancient lava fl ows and shallow intrusions. …


2022 Nebraska Water Leaders Academy Final Report, Mark E. Burbach, Robert Matthew Joeckel, Brooke Mott, Gina S. Matkin 2022 University of Nebraska at Lincoln

2022 Nebraska Water Leaders Academy Final Report, Mark E. Burbach, Robert Matthew Joeckel, Brooke Mott, Gina S. Matkin

Conservation and Survey Division

Fifteen participants completed the 2022 Water Leaders Academy bringing the total number of graduates to 168 since the inception of the program in 2011. Assessments of participants’ transformational leadership skills, champion of innovation skills, water knowledge, engagement with water issues, civic capacity, entrepreneurial leadership behaviors, and boundary spanning skills increased significantly over the course of the year, according to both the participants and their raters. Feedback from the participants was highly positive and constructive. Academy planners are addressing participant concerns. Results of the program assessment indicate that the curriculum is meeting Academy objectives. Therefore, only minor changes are planned for …


Alien Foraminifers Of The Northern And Northeastern Coastlines Of Cyprus Island, Engin MERİÇ, M. Baki YOKEŞ, İpek F. BARUT, Atike NAZİK, Mustafa ERYILMAZ, Fulya YÜCESOY ERYILMAZ, M. Fatih HÜSEYİNOĞLU, Mustafa KUMRAL, Erol SARI 2021 Bulletin of the Mineral Research and Exploration

Alien Foraminifers Of The Northern And Northeastern Coastlines Of Cyprus Island, Engin Meri̇ç, M. Baki Yokeş, İpek F. Barut, Atike Nazi̇k, Mustafa Eryilmaz, Fulya Yücesoy Eryilmaz, M. Fatih Hüseyi̇noğlu, Mustafa Kumral, Erol Sari

Bulletin of the Mineral Research and Exploration

The study area covers the northern coasts of Cyprus from the Güzelyurt Gulf to the Gazimağusa Gulf. This study was carried out in order to reveal the presence of the alien foraminifera, which are widely distributed in the Eastern Mediterranean particularly Amphistegina lobifera in the study area, and the effects of trace elements on faunal assemblages (foraminifera, ostracod and mollusc). The bottom sediment samples were taken from eighteen different points and depths, the faunal assemblages were examined, and the sediment distribution map of the studied area was made by ICP-MS analysis and geochemical evaluations. 30 genera and 48 species of …


New Age Findings With Microfossils Of The Van Formation (Van, Eastern Anatolia), Ayşegül GÜNEY, Elvan DEMİRCİ, Kemal KORKMAZ, Sefer ÖRÇEN 2021 Bulletin of the Mineral Research and Exploration

New Age Findings With Microfossils Of The Van Formation (Van, Eastern Anatolia), Ayşegül Güney, Elvan Demi̇rci̇, Kemal Korkmaz, Sefer Örçen

Bulletin of the Mineral Research and Exploration

Van Formation, which is mainly represented by conglomerate, sandstone, marl and limestone, covers a large area around the Van province. The age of the unit was assigned in different localities of the region as late Oligocene - middle Miocene, early Miocene, Burdigalian - Langhian (early - middle Miocene) by previous studies. In order to determine the age of the upper levels of the formation in the east and southeast of Lake Van, a total of 98 samples collected from three measured stratigraphic sections. These samples have been examined in terms of calcareous nannoplankton and planktonic foraminiferal content. 33 species of …


Stratigraphic Analysis Of The Capps Limestone In The North Norton Oil Field In Runnels County, Texas, William Thompson 2021 Stephen F. Austin State University

Stratigraphic Analysis Of The Capps Limestone In The North Norton Oil Field In Runnels County, Texas, William Thompson

Electronic Theses and Dissertations

The Desmoinesian (Middle Pennsylvanian) Capps Limestone Member of the Mineral Wells Formation is a carbonate reservoir located in North Central Texas. It consists of interbedded limestone, sandstone, and shale units. Much of the Capps Limestone exists in the subsurface of Brown, Coleman, Runnels, Coke, Nolan, and Taylor counties, however, the Capps Limestone outcrops on the surface in Brown, Eastland, and Palo Pinto counties.

The cored interval from Runnels County was deposited in a marginal marine environment during the Middle Pennsylvanian Period. Although the Capps Limestone was first described in the 1890s, there is still much to be discovered about its …


Analyzing Weathering Patterns In Modern And Paleolake Deposits Of Tecopa, California: Implications For The Detection Of Paleolakes On Mars, Jason Benjamin Carman 2021 University of Wisconsin-Milwaukee

Analyzing Weathering Patterns In Modern And Paleolake Deposits Of Tecopa, California: Implications For The Detection Of Paleolakes On Mars, Jason Benjamin Carman

Theses and Dissertations

This study focuses on two stratigraphic sections from the Tecopa paleolake and samples from the modern Tecopa and Amargosa River basins as a terrestrial analogue to Martian paleolakes. Previous work shows that the later stages of Pleistocene Lake Tecopa were highly alkaline and saline due to evaporation, which led to the formation of authigenic lacustrine minerals such as zeolites, clays, and precipitates that are potentially similar to Martian paleolakes. Paleolakes can provide information on past aqueous processes, such as the changes in the hydrologic cycle that a particular area experienced over the lifespan of a lake on Earth or Mars. …


Distinguishing Mustela From Neogale (Mustelidae) Through Both A Qualitative And Quantitative Analysis Of Skull And Tooth Morphology, Ronald W. Peery 2021 East Tennessee State University

Distinguishing Mustela From Neogale (Mustelidae) Through Both A Qualitative And Quantitative Analysis Of Skull And Tooth Morphology, Ronald W. Peery

Electronic Theses and Dissertations

Weasels and mink (Mustela and Neogale) can be difficult to distinguish osteologically due to similarities in morphology, thus suggesting the need for an accurate tool in distinguishing among taxa. This study utilized a combination of character state and stepwise discriminant function (DFA) analyses to examine potential distinguishing features of skull and tooth morphology. Measurements and ratios were collected from all 18 extant musteline species, as well as the extinct Neovison macrodon, Mustela rexroadensis, Mustela meltoni, Mustela gazini, and Mustela jacksoni. Unidentified musteline specimens from the Gray Fossil Site were also included. Results of …


Taphonomic And Diagenetic Pathways To Protein Preservation, Part I: The Case Of Tyrannosaurus Rex Specimen Mor 1125, Paul Ullmann, Kyle Macauley, Richard Ash, Ben Shoup, John Scanella 2021 Rowan University

Taphonomic And Diagenetic Pathways To Protein Preservation, Part I: The Case Of Tyrannosaurus Rex Specimen Mor 1125, Paul Ullmann, Kyle Macauley, Richard Ash, Ben Shoup, John Scanella

School of Earth & Environment Faculty Scholarship

Contrary to traditional views, fossil bones have been shown to occasionally retain original cells, blood vessels, and structural tissues that are still comprised, in part, by their original proteins. To help clarify how such remarkable preservation occurs, we explored the fossilization history of a famous Tyrannosaurus rex specimen previously shown to yield original cells, vessels, and collagen protein sequences. By analyzing the trace element composition of the femur of this tyrannosaur, we show that after death its carcass decayed underwater in a brackish, oxic, estuarine channel and then became buried by sands that quickly cemented around the bones, largely protecting …


Crab In Amber Reveals An Early Colonization Of Nonmarine Environments During The Cretaceous, Javier Luque, Lida Xing, Derek E. G. Briggs, Elizabeth G. Clark, Alex Duque, Junbo Hui, Huijuan Mai, Ryan C. McKellar 2021 Harvard University

Crab In Amber Reveals An Early Colonization Of Nonmarine Environments During The Cretaceous, Javier Luque, Lida Xing, Derek E. G. Briggs, Elizabeth G. Clark, Alex Duque, Junbo Hui, Huijuan Mai, Ryan C. Mckellar

Faculty and Staff Publications & Presentations

Amber fossils provide snapshots of the anatomy, biology, and ecology of extinct organisms that are otherwise inaccessible. The best-known fossils in amber are terrestrial arthropods—principally insects—whereas aquatic organisms are rarely represented. Here, we present the first record of true crabs (Brachyura) in amber—from the Cretaceous of Myanmar [~100 to 99 million years (Ma)]. The new fossil preserves large compound eyes, delicate mouthparts, and even gills. This modern-looking crab is nested within crown Eubrachyura, or “higher” true crabs, which includes the majority of brachyuran species living today. The fossil appears to have been trapped in a brackish or freshwater setting near …


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