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Investigation Of A Recent Landslide In Fort Smith, Arkansas, D. Mayo, M.J. Thomas, A. Burns, J. Pruitt, P. Karr Jan 2023

Investigation Of A Recent Landslide In Fort Smith, Arkansas, D. Mayo, M.J. Thomas, A. Burns, J. Pruitt, P. Karr

Journal of the Arkansas Academy of Science

A morphologically youthful slope failure, herein referred to as the Landfill Landslide, was identified in a remote section of the City of Fort Smith Landfill, and permission was obtained to investigate. The slide on a deforested, NW-facing 27% slope beneath a linear head scarp about 200 meters long. One end of the head scarp curves abruptly downhill and transforms into a distinct lateral scarp greater than 100 meters long. The surface of the slide is about 24,000 m2 (6 acres) in area and is easily distinguished from adjacent intact slopes by its hummocky morphology and transverse ridges and valleys. The …


Determination Of Fatty Acid Concentrations In Various Strains Of Freshwater Green Picoplankton Algae (Class Eustigmatophyceae), P. Ashcraft, R. Jacks, B. Martinez, J. Rodriguez, A.B. Burns, A. Gurnsey, L. Taylor, A. Teague, J. Totty, V.L. Fox, A. Williams Jan 2023

Determination Of Fatty Acid Concentrations In Various Strains Of Freshwater Green Picoplankton Algae (Class Eustigmatophyceae), P. Ashcraft, R. Jacks, B. Martinez, J. Rodriguez, A.B. Burns, A. Gurnsey, L. Taylor, A. Teague, J. Totty, V.L. Fox, A. Williams

Journal of the Arkansas Academy of Science

Algae are of scientific and commercial interest due to their ease of culture and high fatty acid content. The extracted fatty acids from these phytoplankton may potentially be used as an additional test for phylogenetic classification of new algal strains (Tonon et al. 2002), as well as in a supplement for human consumption and producing next-generation biofuels. Of interest is the fatty acid content contained within various algal isolates within the class Eustigmatophyceae. Algal strains were collected and isolated from locations in Lake Chicot in Arkansas, Tower Pond and Lake Itasca at Itasca State Park in Minnesota, and Thayer Lake …


Journal Of The Arkansas Academy Of Science Volume 77, Academy Editors Jan 2023

Journal Of The Arkansas Academy Of Science Volume 77, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Determining Mating Type And Species Of A Natural Isolate Of Dictyostelium Using Molecular Techniques And Sexual Crosses, S.N. Baviskar, C. Catron, H. Jenkins, M. Smith Jan 2023

Determining Mating Type And Species Of A Natural Isolate Of Dictyostelium Using Molecular Techniques And Sexual Crosses, S.N. Baviskar, C. Catron, H. Jenkins, M. Smith

Journal of the Arkansas Academy of Science

Cellular slime molds, Dictyostelium, are bactivorous, soil-dwelling amoebae. When food is available, cells reproduce asexually by binary fission. Under certain environmental conditions, such as darkness and humidity, Dictyostelium reproduces sexually. The sexual cycle is uniquely social and has unusual features. First, sexual reproduction in most eukaryotes usually involves fusion of two gametes. But, in Dictyostelium, triparental inheritance is observed (Bloomfield et al. 2019), in which gamete fusion involves more than two gametes. Second, most eukaryotic species have two sexes or mating types, but Dictyostelium species are known to have more than two mating types. Even though Dictyostelium species show variations …


Noteworthy Parasites (Trematoda, Cestoda, Phthiraptera) Of Three Birds (Aves: Passeriformes; Pelecaniformes; Piciformes) From Arkansas, C.T. Mcallister, H.W. Robison Jan 2023

Noteworthy Parasites (Trematoda, Cestoda, Phthiraptera) Of Three Birds (Aves: Passeriformes; Pelecaniformes; Piciformes) From Arkansas, C.T. Mcallister, H.W. Robison

Journal of the Arkansas Academy of Science

Between November 2020 and March 2021, three species of birds, one each of a tufted titmouse (Baeolophus bicolor), pileated woodpecker (Dryocopus pileatus), and great blue heron (Ardea herodias) were salvaged from Lawrence and Polk counties, Arkansas, and examined for parasites. Found were four taxa of parasites, including a dicrocoeliid trematode, a cyclophyllidean cestode, and species of philopterid and menoponid lice. We document new host and distributional records for these parasites from select birds of the state.


Spermiogenesis In The Western Siren, Siren Nettingi (Caudata: Sirenidae), S.E. Trauth Jan 2023

Spermiogenesis In The Western Siren, Siren Nettingi (Caudata: Sirenidae), S.E. Trauth

Journal of the Arkansas Academy of Science

I investigated spermiogenesis in the Western Siren, Siren nettingi (formerly Western Lesser Siren, Siren intermedia nettingi) from salamanders collected periodically over a span of 21 yr (1994–2015) in northeastern Arkansas. My primary objective in this study is to present histologically and ultrastructurally, for the first time, the novel sequence of spermatological events of the spermiogenic process in this species. I describe the transformational stages from secondary spermatocytes to mature biflagellated spermatozoa, all of which occur within the lumen of testicular lobules. These new-to-science processes begin with nuclear displacement and expansion within spermatids, which occur after their detachment from Sertoli cells …


Histomorphology Of The Distal Urogenital Ducts In The Male Northern Crawfish Frog, Rana Areolata Circulosa (Anura: Ranidae), S.E. Trauth, R.G. Neal Jan 2023

Histomorphology Of The Distal Urogenital Ducts In The Male Northern Crawfish Frog, Rana Areolata Circulosa (Anura: Ranidae), S.E. Trauth, R.G. Neal

Journal of the Arkansas Academy of Science

We examined the microanatomy of the distal urogenital ducts in the male Northern Crawfish Frog (Rana areolata circulosa) from a small sample (n = 5) collected in February and March from central Arkansas over a 5-year period (2017–2022). Specifically, we sought information on the following structures: (1) the paired Wolffian (urogenital) ducts caudally from the kidneys to their merging with the urodeum of the cloaca, (2) the paired seminal vesicles (sperm storage structures), and (3) the paired Müllerian ducts and glands. This study provides new information on these urogenital ducts and promotes a clearer understanding of this anatomical region for …


No Sperm Morphometric Differences Between Two Snapping Turtle Species, J.D. Konvalina, S.E. Trauth Jan 2023

No Sperm Morphometric Differences Between Two Snapping Turtle Species, J.D. Konvalina, S.E. Trauth

Journal of the Arkansas Academy of Science

We examined sperm morphometrics between Chelydra serpentina and Macrochelys temminckii. When both species are combined, we found significant correlations between total sperm length and sperm head length as well as sperm tail length and sperm head length. In addition, we observed significant correlations between total sperm length and sperm tail length. T-tests revealed no significant differences in any of the sperm morphometrics between the two species. Both snapping turtle species had greater values for every sperm morphometric when compared to another freshwater turtle. The strong correlation between total sperm length and sperm tail length is concurrent with what has previously …


Keynote Address And Meeting Program, Academy Editors Jan 2023

Keynote Address And Meeting Program, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Instructions To Authors, Academy Editors Jan 2023

Instructions To Authors, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Magnetic Anomaly Data Products Of The Central And Eastern United States, Dhananjay Ravat Jan 2023

Magnetic Anomaly Data Products Of The Central And Eastern United States, Dhananjay Ravat

Earth and Environmental Sciences Research Data

This data set contains Central and Eastern U.S. Magnetic Anomaly, DRTP, Tilt Derivative, and Analytic Signal Amplitude Products ultimately derived from Ravat, D., Finn, C., Hill, P., Kucks, R., Phillips, J., Blakely, R., Bouligand, C., Sabaka, T., Elshayat, A., Aref, A., and Elawadi, E., 2009, A preliminary, full spectrum, magnetic anomaly grid of the United States with improved long wavelengths for studying continental dynamics--A website for distribution of data: U.S. Geological Survey Open- File Report 2009–1258, 2 p.


Magnetotelluric Insights Into The Formation And Reactivation Of Trans-Crustal Shear Zones In Precambrian Basement Of The Eastern U.S. Midcontinent, Benjamin S. Murphy, Michael S. Delucia, Stephen Marshak, Dhananjay Ravat, Paul A. Bedrosian Jan 2023

Magnetotelluric Insights Into The Formation And Reactivation Of Trans-Crustal Shear Zones In Precambrian Basement Of The Eastern U.S. Midcontinent, Benjamin S. Murphy, Michael S. Delucia, Stephen Marshak, Dhananjay Ravat, Paul A. Bedrosian

Earth and Environmental Sciences Faculty Publications

Three-dimensional inversion of regional long-period magnetotelluric (MT) data re- veals the presence of two distinct sets of high-conductivity belts in the Precambrian basement of the eastern U.S. Midcontinent. One set, beneath Missouri, Illinois, Indiana, and western Ohio, is defined by northwest– southeast-oriented conductivity structures; the other set, beneath Kentucky, West Vir- ginia, western Virginia, and eastern Ohio, in- cludes structures that are generally oriented northeast–southwest. The northwest-trend- ing belts occur mainly in Paleoproterozoic crust, and we suggest that their high con- ductivity values are due to graphite precipi- tated within trans-crustal shear zones from intrusion-related CO2-rich fluids. Our MT inversion …


Terrestrial Ecosystem Transformations In Response To Rapid Climate Change During The Last Deglaciation Around Mono Lake, California, Usa, Adam J. Benfield, Sarah J. Ivory, Bailee Nicole Hodelka, Susan R. H. Zimmerman, Michael M. Mcglue Jan 2023

Terrestrial Ecosystem Transformations In Response To Rapid Climate Change During The Last Deglaciation Around Mono Lake, California, Usa, Adam J. Benfield, Sarah J. Ivory, Bailee Nicole Hodelka, Susan R. H. Zimmerman, Michael M. Mcglue

Earth and Environmental Sciences Faculty Publications

We examine major reorganizations of the terrestrial ecosystem around Mono Lake, California during the last deglacial period from 16,000–9,000 cal yr BP using pollen, microcharcoal, and coprophilous fungal spores (Sporormiella) from a deep-water sediment core. The pollen results record the assemblage, decline, and replacement of a mixed wooded community of Sierran and Great Basin taxa with Alkali Sink and Sagebrush Steppe biomes around Mono Lake. In particular, the enigmatic presence of Sequoiadendron-type pollen and its extirpation during the early Holocene hint at substantial biogeographic reorganizations on the Sierran-Great Basin ecotone during deglaciation. Rapid regional hydroclimate changes produced structural alterations in …


Eocene To Oligocene Cooling And Ice Growth Based On The Geochemistry Of Interglacial Mudstones From The East Antarctic Continental Shelf, Jennifer J. Light, Sandra Passchier Jan 2023

Eocene To Oligocene Cooling And Ice Growth Based On The Geochemistry Of Interglacial Mudstones From The East Antarctic Continental Shelf, Jennifer J. Light, Sandra Passchier

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The Eocene-Oligocene Transition at c. 34 million years ago (Ma) marked the global change from greenhouse to icehouse and the establishment of the East Antarctic Ice Sheet (EAIS). How the ice-sheet behaviour changed during interglacials across this climate transition is poorly understood. We analysed major, trace and rare earth elemental data of late Eocene interglacial mudstone from Prydz Bay at Ocean Drilling Program Site 1166 and early Oligocene interglacial mudstone from Integrated Ocean Drilling Program Site U1360 on the Wilkes Land continental shelf. Both sites have comparable glaciomarine depositional settings. Lithofacies and provenance at Site 1166 in Prydz Bay are …


Modeling Monthly Actual Evapotranspiration: An Application Of Geographically Weighted Regression Technique In The Passaic River Basin, Felix Oteng Mensah, Clement Aga Alo Jan 2023

Modeling Monthly Actual Evapotranspiration: An Application Of Geographically Weighted Regression Technique In The Passaic River Basin, Felix Oteng Mensah, Clement Aga Alo

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Actual evapotranspiration (ET) is perhaps the most difficult quantity to directly measure among the major water balance components. Because of the high cost and labor constraints associated with the direct measurement of ET, empirical data-driven modeling has frequently been used to estimate ET. Beyond the widely used traditional type regression that has the effect of producing ‘global’ parameter estimates, assumed to be uniform throughout an area, we utilized a more localized spatially non-stationary technique - the geographically weighted regression (GWR) - to estimate mean monthly ET in the Passaic River Basin (PRB). We identified the key environmental controls of ET …


Geological And Environmental Sciences - 2023, Dept. Of Geological And Environmental Sciences Jan 2023

Geological And Environmental Sciences - 2023, Dept. Of Geological And Environmental Sciences

Geological and Environmental Sciences News

  • Greetings from the Department Chair
  • Faculty Updates
  • MGRRE Updates
  • MGS Updates
  • Geosciences Advisory Council
  • 2023 Distinguished Alumni Franklyn Legall
  • Student Clubs
  • Awards and Honors, 2023
  • Department Graduates
  • Publications 2022–23
  • Gifts and Donors


Accuracy Assessment Of The Ebee Using Rtk And Ppk Corrections Methods As A Function Of Distance To A Gnss Base Station, Joseph Cerreta, David Thirtyacre, Peter Miller, Scott S. Burgess, William J. Austin Jan 2023

Accuracy Assessment Of The Ebee Using Rtk And Ppk Corrections Methods As A Function Of Distance To A Gnss Base Station, Joseph Cerreta, David Thirtyacre, Peter Miller, Scott S. Burgess, William J. Austin

International Journal of Aviation, Aeronautics, and Aerospace

The use of unmanned aircraft systems to collect data for photogrammetry models has grown significantly in recent years. The accuracy of a photogrammetric model can depend on image georeferencing. The distance from a reference base station can affect the accuracy of the results. Positioning corrections data relies on precise timing measurements of satellite signals. The signals travel through the Earth's atmosphere, which introduces errors due to ionospheric and tropospheric delays. The aim of this research was to examine the eBee X and its global GNSS accuracy by comparing the RTK and PPK methods at different base station distances in photogrammetry …


Historical And Forecasted Kentucky Specific Slope Stability Analyses Using Remotely Retrieved Hydrologic And Geomorphologic Data, Daniel M. Francis Jan 2023

Historical And Forecasted Kentucky Specific Slope Stability Analyses Using Remotely Retrieved Hydrologic And Geomorphologic Data, Daniel M. Francis

Theses and Dissertations--Civil Engineering

Hazard analyses of rainfall-induced landslides have typically been observed to experience a lack of inclusion of measurements of soil moisture within a given soil layer at a site of interest. Soil moisture is a hydromechanical variable capable of both strength gains and reductions within soil systems. However, in situ monitoring of soil moisture at every site of interest is an unfeasible goal. Therefore, spatiotemporal estimates of soil moisture that are representative of in-situ conditions are required for use in subsequent landslide hazard analyses.

This study brings together various techniques for the acquisition, modeling, and forecasting of spatiotemporal retrievals of soil …


Soil Moisture And Geomorphologic Data For Use In Dynamic And Forecastable Landslide Hazard Analyses In Eastern Kentucky, Daniel M. Francis, L. Sebastian Bryson Jan 2023

Soil Moisture And Geomorphologic Data For Use In Dynamic And Forecastable Landslide Hazard Analyses In Eastern Kentucky, Daniel M. Francis, L. Sebastian Bryson

Civil Engineering Research Data

These data are the geomorphologic and land information system-based soil moisture estimates from assimilation of NASA SMAP satellite-based observations and NOAH 3.6 Land Surface Model estimates over known landslides in Eastern Kentucky. Additionally Long Short-Term Memory Recurrent Neural Network and logistic regression machine learning codes, as well as an Application programming interface code are included. Finally, in-situ data from Eastern Kentucky is included.


Evaluating Benthic Macroinvertebrate Populations In Response To Scouring Events In The Trinity River, Ca, Liam Hay, Michael W. O'Neil, Chloe Pieper-Wasem Jan 2023

Evaluating Benthic Macroinvertebrate Populations In Response To Scouring Events In The Trinity River, Ca, Liam Hay, Michael W. O'Neil, Chloe Pieper-Wasem

Environmental Science & Management Senior Capstones

River systems across California have been impacted by appurtenant structures such as dams and diversions. These structures have had an adverse impact on Benthic invertebrate (BMI) communities by regulating river systems and changing the natural hydraulic pulses that follow seasonal precipitation. Benthic invertebrates are a critical food resource for salmonids and serve as an indicator of ecosystem health. Our study was interested in seeing the effects of scouring events on BMI in the Trinity River of Trinity County, C.A. Following a large precipitation event that occurred in the region in December 2022, an influx of water entered the river through …


Vanadium Partitioning Between Magnetite, Hematite, And A Hydrothermal Fluid: Implications For Iocg And Ioa Deposits, Jeremy Raymond Nederbo Jan 2023

Vanadium Partitioning Between Magnetite, Hematite, And A Hydrothermal Fluid: Implications For Iocg And Ioa Deposits, Jeremy Raymond Nederbo

Graduate Research Theses & Dissertations

Iron oxide-copper-gold (IOCG) and iron oxide-apatite (IOA) deposits are major sources of iron contained within magnetite and/or hematite as well as copper contained within copper-iron sulfides and gold as a native metal. Their formations have been attributed to magmatic, hydrothermal, or a mixture of magmatic-hydrothermal processes. Vanadium can readily substitute into magnetite via ion exchange due to similar atomic radii and charges as iron and has thus been hypothesized to be an effective tracer of hydrothermal or magmatic inputs. To evaluate the mobility of vanadium in a magnetite-hematite-fluid system, experiments on the partitioning of vanadium between magnetite, hematite and a …


Precise Zircon U-Pb Dating Of The Mesoproterozoic Gawler Large Igneous Province, South Australia, Elizabeth A. Jagodzinski, Anthony J. Reid, James L. Crowley, Claire E. Wade, Stacey Curtis Jan 2023

Precise Zircon U-Pb Dating Of The Mesoproterozoic Gawler Large Igneous Province, South Australia, Elizabeth A. Jagodzinski, Anthony J. Reid, James L. Crowley, Claire E. Wade, Stacey Curtis

Geosciences Faculty Publications and Presentations

The Mesoproterozoic Gawler Range Volcanics and Benagerie Volcanic Suite of the Gawler Craton and Curnamona Province, South Australia, together with associated intrusive magmatism, define an intracontinental, subaerial large igneous province (LIP) preserving an estimated 110 000 km3 of volcanic rock, which hosts one of the world's largest orebodies, the Fe oxide-Cu-Au-U deposit at Olympic Dam, and numerous other related Cu-Au deposits. New high-precision Chemical Abrasion Isotope Dilution Thermal Ionization Mass Spectrometry (CA-TIMS) U-Pb dates on volcanic zircons allow for regional correlations between stratigraphic units of the GRV and BVS, and an understanding of how magmatic styles, temperatures, composition and …


Drivers Of Spatiotemporal Patterns Of Surface Water Inputs In A Catchment At The Rain-Snow Transition Zone Of The Water-Limited Western United States, E. Trujillo, J. Mcnamara Jan 2023

Drivers Of Spatiotemporal Patterns Of Surface Water Inputs In A Catchment At The Rain-Snow Transition Zone Of The Water-Limited Western United States, E. Trujillo, J. Mcnamara

Geosciences Faculty Publications and Presentations

Spatial and temporal dynamics of rainfall and snowmelt (i.e., surface water inputs, SWI) control soil moisture, groundwater recharge, and streamflow at annual, seasonal, and event scales. In the rain-snow transition zone, comprising a large portion of the mountainous western United States, there is limited understanding of the sensitivity of spatiotemporal SWI dynamics across hydrologically variable water years (WYs). We modeled rainfall and snowpack dynamics in a small headwater catchment (1.8 km2) spanning the rain-snow transition in southwestern Idaho, USA, for two hydrologically distinct WYs (2011 and 2014). In wet WY 2011 and dry WY 2014, total precipitation drove …


Elastic Thermobarometry, Matthew J. Kohn, Mattia L. Mazzucchelli, Matteo Alvaro Jan 2023

Elastic Thermobarometry, Matthew J. Kohn, Mattia L. Mazzucchelli, Matteo Alvaro

Geosciences Faculty Publications and Presentations

Upon exhumation and cooling, contrasting compressibilities and thermal expansivities induce differential strains (volume mismatches) between a host crystal and its inclusions. These strains can be quantified in situ using Raman spectroscopy or X-ray diffraction. Knowing equations of state and elastic properties of minerals, elastic thermobarometry inverts measured strains to calculate the pressure-temperature conditions under which the stress state was uniform in the host and inclusion. These are commonly interpreted to represent the conditions of inclusion entrapment. Modeling and experiments quantify corrections for inclusion shape, proximity to surfaces, and (most importantly) crystal-axis anisotropy, and they permit accurate application of the more …


Pacific Northwest Streamflow Data Landscape: A Report From The 2022 Streamflow Data Roundtables, Kendra E. Kaiser Jan 2023

Pacific Northwest Streamflow Data Landscape: A Report From The 2022 Streamflow Data Roundtables, Kendra E. Kaiser

Geosciences Faculty Publications and Presentations

This project was funded by the U.S. Geological Survey Northwest Climate Adaptation Science Center to catalog the location, temporal extent and purpose of non-USGS streamflow datasets. As part of this project, roundtable meetings convened local, state and federal agencies, and nonprofits to explore the complexity of gathering and integrating the identified datasets and identify issues surrounding data-sharing across organizations.

This report synthesizes discussions from each of the state roundtable discussions convened in the spring of 2022, and highlights common challenges and needs across the region. Additional information from organizations not able to be present at the meetings were added after …


New Age Constraints On The Break-Up Of Rodinia And Amalgamation Of Southwestern Gondwana From The Choquequirao Formation In Southwestern Peru, Eben Blake Hodgin, Victor Carlotto, Francis A. Macdonald, Mark D. Schmitz, James L. Crowley Jan 2023

New Age Constraints On The Break-Up Of Rodinia And Amalgamation Of Southwestern Gondwana From The Choquequirao Formation In Southwestern Peru, Eben Blake Hodgin, Victor Carlotto, Francis A. Macdonald, Mark D. Schmitz, James L. Crowley

Geosciences Faculty Publications and Presentations

The Choquequirao Formation is a >3 km-thick amphibolite-grade succession that outcrops in the Central Andes of southern Peru. To constrain its age and tectonostratigraphic setting, detrital zircon and metamorphic zircon, titanite, and rutile U–Pb isotopic analyses were conducted. Mantle-derived c. 640 Ma detrital zircons constrain the maximum age of the lower part of the succession and 550–490 Ma metamorphic zircon domains constrain its minimum age. The absence of early Paleozoic detrital zircons suggests that deposition predated early Paleozoic orogenesis in southwestern Gondwana. The close similarity of detrital zircon age spectra to those from sediments deposited on the Arequipa basement suggests …


Spatiotemporal Retrievals Of Soil Moisture And Geomorphologic Data For Landslide Sites In Eastern Kentucky, Lindsey Sebastian Bryson, Daniel M. Francis Jan 2023

Spatiotemporal Retrievals Of Soil Moisture And Geomorphologic Data For Landslide Sites In Eastern Kentucky, Lindsey Sebastian Bryson, Daniel M. Francis

Civil Engineering Research Data

These data are the soil texture, land information system-based soil moisture estimates from assimilation of NASA SMAP satellite-based observations and NOAH 3.6 Land Surface Model estimates, artificial neural network machine learning code, and in-situ soil moisture measurements.


Reconstructing The Ecological Relationships Of The Latest Cretaceous Antarctic Dinosaurs And How Functional Tooth Morphology Influenced Diet And Ecological Niche Among Basal Ornithopod Dinosaurs, Ian Broxson Jan 2023

Reconstructing The Ecological Relationships Of The Latest Cretaceous Antarctic Dinosaurs And How Functional Tooth Morphology Influenced Diet And Ecological Niche Among Basal Ornithopod Dinosaurs, Ian Broxson

EWU Masters Thesis Collection

Of the final three connected Gondwanan landmasses, the dinosaur fossil record of Antarctica in the Cretaceous is the least complete. Most dinosaur faunas in this time period (145 Ma to 66.0 Ma) are widely separated geographically and temporally from one another by million years. However, a group of non-avian dinosaurs from the James Ross Basin (JRB) of the Antarctic Peninsula, composed of two elasmarians, a parankylosaurian ankylosaur, a hadrosaur and a suspected megaraptor, all are represented by fragmentary remains have emerged from the same horizon of the Sandwich Bluff Member (SBM) of the López de Bertodano Formation and were thus, …


Dvgq Joint Data, Steven L. Martin Jan 2023

Dvgq Joint Data, Steven L. Martin

Research Data--KGS

A compilation of digitally vectorized joint data from the U.S. Geological Survey geologic quadrangle maps. Joint data was collected by USGS and KGS geologists using a compass during geologic mapping of the 7.5-minute quadrangle. Field notes of mappers are not available, therefore the orientation of joints was determined by a script written by KGS personnel during the digitization process.


Pithonellid Calcitarch Record In The Middle? Cenomanian Derdere-A Member, Se Turkey: Palaeoenvironmental Changes And Stratigraphic Significance, Oğuz Mülayi̇m, İsmai̇l Ömer Yilmaz, Bruno Ferré Jan 2023

Pithonellid Calcitarch Record In The Middle? Cenomanian Derdere-A Member, Se Turkey: Palaeoenvironmental Changes And Stratigraphic Significance, Oğuz Mülayi̇m, İsmai̇l Ömer Yilmaz, Bruno Ferré

Turkish Journal of Earth Sciences

Pithonellid calcitarchs are studied in the organic-rich limestones of the Derdere-A Member from the middle? Cenomanian deposits of SE Turkey for the first time. Little is known about the distribution of pithonellid calcitarchs in the Cretaceous strata of Turkey. Three morphogroups of pithonellid calcitarchs are distinguished: they are represented by Pithonella sphaerica (Kaufmann, 1865) and P. ovalis (Kaufmann, 1865), both dominating the pithonellid assemblages, and by Bonetocardiella conoidea (Bonet, 1956), this latter being less abundant. Compared to the relative abundance of Upper Cretaceous pithonellid calcitarchs in the study area, the diversity is extremely low. The significant increase in abundance of …