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Articles 1501 - 1530 of 3980
Full-Text Articles in Entire DC Network
Analysis Of A Paleoglacier Reconstruction Model For Valley Glaciers Of The Wind River Range, Wyoming, Taylor Rae Garton
Analysis Of A Paleoglacier Reconstruction Model For Valley Glaciers Of The Wind River Range, Wyoming, Taylor Rae Garton
Dissertations and Theses @ UNI
Various approaches, ranging from in-field morphological reconstructions to more technology-based modelling practices allow us to reconstruct and understand the long-term geomorphic evolution of landscapes. The study of paleo-environments by reconstruction can also give us profound insight into paleo-climate. A new model, GlaRe (Glacial Reconstruction), has been introduced into the alpine glacier modeling community to facilitate glacier reconstruction. In this research the mathematical equations representing the basal shear stress parameter are tested to determine the applicability of the GlaRe model to alpine glaciers in the American West. Known ages and extents of past glacier advances were used to test the reconstructions …
Computer Vision-Based Traffic Sign Detection And Extraction: A Hybrid Approach Using Gis And Machine Learning, Zihao Wu
College of Graduate Studies: Theses & Dissertations
Traffic sign detection and positioning have drawn considerable attention because of the recent development of autonomous driving and intelligent transportation systems. In order to detect and pinpoint traffic signs accurately, this research proposes two methods. In the first method, geo-tagged Google Street View images and road networks were utilized to locate traffic signs. In the second method, both traffic signs categories and locations were identified and extracted from the location-based GoPro video. TensorFlow is the machine learning framework used to implement these two methods. To that end, 363 stop signs were detected and mapped accurately using the first method (Google …
Death-Defying Morphologies: Mass Extinction And Disparity In The Order Harpetida, James Desmond Beech
Death-Defying Morphologies: Mass Extinction And Disparity In The Order Harpetida, James Desmond Beech
Graduate Theses, Dissertations, and Problem Reports (ETD)
The trilobite order Harpetida has long been easily recognized but poorly understood. This study seeks to better understand the phylogenetic relationships within Harpetida, with a view towards using this group to explore the relationship between extinction intensity and disparity. The harpetid response to the Late Ordovician mass extinction is of particular interest. A discrete morphological character matrix was created from the formal descriptions of harpetids in the published trilobite literature, and refined using first-hand observations of harpetid fossils. The final matrix consists of 76 discrete characters, including 69 cephalic characters, three thoracic characters, and four pygidial characters. This matrix is …
Utilizing Lipid Biomarkers To Understand The Microbial Community Structure Of Deep Subsurface Black Shale Formations, Rawlings Akondi
Utilizing Lipid Biomarkers To Understand The Microbial Community Structure Of Deep Subsurface Black Shale Formations, Rawlings Akondi
Graduate Theses, Dissertations, and Problem Reports (ETD)
The deep subsurface environment has been known to host microbes as early as 1926 and has also been suggested to potentially account for as much as 50% of the Earth`s biomass. Researchers have shown that microbes alter their membrane lipid components in response to physiological stress, producing stress indicative lipid biomarkers. However, little effort has been made to understand the subsurface microbial community of the shale ecosystem which is increasingly being exploited and altered by addition of drilling and hydraulic fluids to meet our growing energy needs. Phospholipid fatty acids (PLFAs) are microbial lipid biomarkers and are found in all …
Application Of Lidar To 3d Structural Mapping, Bertrand Gaschot
Application Of Lidar To 3d Structural Mapping, Bertrand Gaschot
Graduate Theses, Dissertations, and Problem Reports (ETD)
The rugged, densely forested terrain of the West Virginia Appalachian Valley and Ridge Province has made it difficult for field-based studies to agree on the structure of the highly deformed Silurian-Devonian cover strata. In this study, we demonstrate a 3D approach to geologic mapping utilizing the structural information revealed in a “bare-earth” 1-m Lidar DEM of the Smoke Hole Canyon. The completed 3D map was integrated with kinematic forward modeling carried out in MOVETM to provide information on the parameters required to form the major structures observed. Additionally, land surface attributes generated using geomorphometric analysis of the Lidar allowed …
Petrophysical And Geomechanical Characterization Of The Marcellus Shale In The Appalachian Basin, Yixuan Zhu
Petrophysical And Geomechanical Characterization Of The Marcellus Shale In The Appalachian Basin, Yixuan Zhu
Graduate Theses, Dissertations, and Problem Reports (ETD)
In recent years, more and more attention is paid to shale gas and hydrocarbon liquids exploration and exploitation in unconventional reservoirs. With the development of horizontal drilling and hydraulic fracturing, production from unconventional reservoirs has been greatly increased. However, not all wells, regions and basins harbor highly successful shale gas and liquids producers. In order to improve the production efficiency and reduce the cost of projects, detailed analysis needs to be undertaken to characterize the reservoir. As opposed to conventional reservoirs, extraction of gas in the unconventional reservoir is dependent not only on the reservoir quality, but also on completion …
Sediment Provenance Study Of The Lower Hamilton Group: An Analysis Of The Organic-Rich Facies And Its Depositional History, Luke Patrick Fritz
Sediment Provenance Study Of The Lower Hamilton Group: An Analysis Of The Organic-Rich Facies And Its Depositional History, Luke Patrick Fritz
Graduate Theses, Dissertations, and Problem Reports (ETD)
Currently, insufficient geological models exist to explain the variability and distribution of TOC in the Marcellus Shale, within the Hamilton Group. TOC is one of the several limiting factors for natural gas production within the Marcellus Shale basin. One possible explanation for the low TOC regions is that detrital dilution was variable across the basin, with different sediment sources contributing detritus to low TOC areas, compared to surrounding regions with higher TOC. This hypothesis is tested by analyzing the source composition of inorganic detritus, using elemental and mineralogical proxies, with two cores in the Hamilton Group. The Armstrong #1 core …
A Machine-Aided Seismic Signal Analysis Workflow For Subsurface Faults And Facies Visualization And Interpretation, South Central Anadarko Basin, Oklahoma, Wade Martin
Graduate Theses, Dissertations, and Problem Reports (ETD)
Seismic attribute analysis enhances the understanding of subsurface geology and has continually gained traction in the oil and gas industry since the 1970’s. Many seismic attributes are available for petroleum geoscientists. This research intends to provide insight to an analytical attribute workflow for rock property estimation in the Anadarko basin of Oklahoma that is prolific in oil and gas exploration, with a particular focus on seismic texture. 3-D volumes processed for seismic texture facies and structure enhance geophysical investigation and interpretation of amplitude data. This study will contribute valuable insight to reservoir studies and the potential for texture attribute well …
Compound-Specific Isotope Analysis Of Amino Acids In Biological Tissues: Applications In Forensic Entomology, Food Authentication And Soft-Biometrics In Humans, Mayara Patricia Viana De Matos
Compound-Specific Isotope Analysis Of Amino Acids In Biological Tissues: Applications In Forensic Entomology, Food Authentication And Soft-Biometrics In Humans, Mayara Patricia Viana De Matos
Graduate Theses, Dissertations, and Problem Reports (ETD)
In this work we demonstrate the power of compound-specific isotope analysis (CSIA) to analyze proteinaceous biological materials in three distinct forensic applications, including: 1) linking necrophagous blow flies in different life stages to their primary carrion diet; 2) identifying the harvesting area of oysters for food authentication purposes; and 3) the ability to predict biometric traits about humans from their hair.
In the first application, we measured the amino-acid-level fractionation that occurs at each major life stage of Calliphora vicina (Robineau-Desvoidy) (Diptera: Calliphoridae) blow flies. Adult blow flies oviposited on raw pork muscle, beef muscle, or chicken liver. Larvae, pupae …
Historic Log Buildings As Archives Of Past Forest Ecology, Kristen K. De Graauw
Historic Log Buildings As Archives Of Past Forest Ecology, Kristen K. De Graauw
Graduate Theses, Dissertations, and Problem Reports (ETD)
This dissertation is composed of three separate but related manuscripts with the common theme of using historic log buildings from the central Appalachian Mountain region of eastern North America as ecological archives. In Chapter 1, I explore the biases, limitations, and ecological applications of tree-ring data from historic log buildings. European immigrants selected trees from a forested stand based on species, log sizes, and construction locations. Despite this selection bias, ecological information can be gleaned from historic log buildings, which offer a complementary record of past forest ecology and represent a site type that is not often associated with old-growth …
X-Ray Fluorescence Applications In Mudrock Characterization: Investigations Into Middle Devonian Stratigraphy, Appalachian Basin, Usa, Keithan Garrett Martin
X-Ray Fluorescence Applications In Mudrock Characterization: Investigations Into Middle Devonian Stratigraphy, Appalachian Basin, Usa, Keithan Garrett Martin
Graduate Theses, Dissertations, and Problem Reports (ETD)
Mudrocks are characterized by nanometer-scale pore sizes and nano-darcy permeability, which plays a significant role in hydrocarbon flow during production. Resulting from these characteristics, mudrocks were exclusively considered a source rock, which charged overlying, more porous mediums. Hydraulic fracturing, a technology used to create artificial fractures to liberate hydrocarbons from the reservoir, enabled natural gas to be produced from mudrock reservoirs economically. Over the last fifteen years, this technology motivated research efforts to understand reservoir characteristics of mudrock. These investigations significantly improved our knowledge of mudrock systems, but have also highlighted key areas that are undeveloped and/or where conflicting hypotheses …
Peatlands And Histosols In Canaan Valley National Wildlife Refuge, West Virginia, Mitzy Leigh Schaney
Peatlands And Histosols In Canaan Valley National Wildlife Refuge, West Virginia, Mitzy Leigh Schaney
Graduate Theses, Dissertations, and Problem Reports (ETD)
Canaan Valley in West Virginia contains a greater area of peatlands than any other locality in the mid-Atlantic Highlands. Extensive fieldwork focused on peat stratigraphy and pedology, combined with high-resolution radiocarbon dating, was used to evaluate five peatlands within Canaan Valley National Wildlife Refuge (CVNWR) in the central Appalachian Mountains. One hundred soil cores were profiled and described, 30 with laboratory data, including 52 radiocarbon dates. Calibrated basal peat dates among the five mapped peatlands indicate a late Pleistocene timeframe for the onset of peat genesis, ranging from ~18,600 to ~15,200 cal yr BP. The dates for peat initiation are …
Discerning The Diets Of Sweep-Feeding Eurypterids Through Analyses Of Mesh-Modified Appendage Armature, Emily Samantha Hughes
Discerning The Diets Of Sweep-Feeding Eurypterids Through Analyses Of Mesh-Modified Appendage Armature, Emily Samantha Hughes
Graduate Theses, Dissertations, and Problem Reports (ETD)
Eurypterids were a group of aquatic chelicerates that lived throughout most of the Paleozoic. While swimming eurypterids are generally considered to be active predators, the benthic stylonurine eurypterids appear to have had a mode of life similar to modern horseshoe crabs with the exception of two clades, the Stylonuroidea and the Mycteropoidea, both of which independently evolved modifications for sweep-feeding on their anterior appendages. Among extant suspension feeders, it has been shown that there is a linear correlation between the average spacing of feeding structures and prey sizes. This relationship was extrapolated to the sweep-feeding stylonuroid and mycteropoid eurypterids in …
Structural Style And Stratigraphic Architecture Of The Northeastern Brooks Range, Alaska, Benjamin G. Johnson
Structural Style And Stratigraphic Architecture Of The Northeastern Brooks Range, Alaska, Benjamin G. Johnson
Graduate Theses, Dissertations, and Problem Reports (ETD)
The Arctic Alaska–Chukotka microplate is a large Mesozoic–Cenozoic composite terrane that resides at the northern limit of the North American Cordillera. Although its Mesozoic origins are assuredly linked to the opening of the Amerasian Basin of the Arctic Ocean, its Paleozoic origins can be linked to at least three separate paleocontinents, including northern Laurentia, Baltica, and Siberia. Across the Arctic Alaska portion of the microplate, an internal, mid-Paleozoic suture zone presumably separates rocks of the North Slope subterrane (Laurentian affinity) from a collection of smaller subterranes in the southern Brooks Range and Seward Peninsula (Baltic affinity).
The mountains of the …
Beneath The Gypsum Dunes: Cenozoic History Of Wind And Water From A Core Drilled At White Sands, New Mexico, Jackson Bentley Jakeway
Beneath The Gypsum Dunes: Cenozoic History Of Wind And Water From A Core Drilled At White Sands, New Mexico, Jackson Bentley Jakeway
Graduate Theses, Dissertations, and Problem Reports (ETD)
White Sands, New Mexico is the largest gypsum dune field on planet Earth, the result of reworking of gypsum deposits. The dunes have been well studied, but the Cenozoic history preceding the formation of the dune field has been poorly studied. A core drilled to a depth of 192 ft (58.5 m) beneath the modern dune field contains deposits from saline lakes, sandflats, perennial freshwater lakes, perennial brackish to saline lakes, and saline mudflats.
The core is composed of bottom-growth bedded gypsum, gypsum sandstone and siltstone, mixed siliciclastic-gypsum sandstones and siltstones, laminated siliciclastic mudstones, gypsum mudstones, and carbonate mudstones. Bottom-growth …
Submarine Groundwater Discharge Data At Meter Scale (223ra, 224ra, 226ra, 228ra And 222rn) In Indian River Bay (Delaware, Us), Carlos Duque, Karen L. Knee, Christopher J. Russoniello, Mahmound Sherif, Usama A. Abu Risha, Neil C. Sturchio, Holly A. Michael
Submarine Groundwater Discharge Data At Meter Scale (223ra, 224ra, 226ra, 228ra And 222rn) In Indian River Bay (Delaware, Us), Carlos Duque, Karen L. Knee, Christopher J. Russoniello, Mahmound Sherif, Usama A. Abu Risha, Neil C. Sturchio, Holly A. Michael
Faculty & Staff Scholarship
Abstract
Submarine groundwater discharge (SGD) was sampled at high-spatial resolution in Indian River Bay, DE, USA, in July 2016 to characterize the spatial variability of the activity of the radium and radon isotopes commonly used to estimate SGD. These data were part of an investigation into the methods and challenges of characterizing SGD rates and variability, especially in the coastal aquifer transition from freshwater to saltwater (Hydrogeological processes and near shore spatial variability of radium and radon isotopes for the characterization of submarine groundwater discharge (Duque et al., 2019)). Samples were collected with seepage meters and minipiezometers to obtain sufficient …
Geochronology And Depositional History Of The Sandy Springs Aeolian Landscape In The Unglaciated Upper Ohio River Valley, United States, Mathew P. Purtill, J. Steven Kite, Steven L. Forman
Geochronology And Depositional History Of The Sandy Springs Aeolian Landscape In The Unglaciated Upper Ohio River Valley, United States, Mathew P. Purtill, J. Steven Kite, Steven L. Forman
Faculty & Staff Scholarship
The study of active and stabilized late Quaternary aeolian landforms provides important proxies for past climate events and environmental transitions. Despite an overall increase in the study of aeolian landforms in previously glaciated and coastal settings in eastern North America, the history of aeolian sedimentation in many unglaciated inland alluvial settings remain poorly understood. This study reports on the geochronology and depositional history of aeolian landforms and sediments in the unglaciated upper Ohio Valley at the Sandy Springs site. Aeolian landforms and sediments include complex, linear, barchan-like, and climbing dunes; an interdune sand sheet; and sandy loess that blankets high …
Large-Area, High Spatial Resolution Land Cover Mapping Using Random Forests, Geobia, And Naip Orthophotography: Findings And Recommendations, Aaron E. Maxwell, Michael P. Strager, Timothy A. Warner, Christopher A. Ramezan, Alice N. Morgan, Cameron E. Pauley
Large-Area, High Spatial Resolution Land Cover Mapping Using Random Forests, Geobia, And Naip Orthophotography: Findings And Recommendations, Aaron E. Maxwell, Michael P. Strager, Timothy A. Warner, Christopher A. Ramezan, Alice N. Morgan, Cameron E. Pauley
Faculty & Staff Scholarship
Despite the need for quality land cover information, large-area, high spatial resolution land cover mapping has proven to be a difficult task for a variety of reasons including large data volumes, complexity of developing training and validation datasets, data availability, and heterogeneity in data and landscape conditions. We investigate the use of geographic object-based image analysis (GEOBIA), random forest (RF) machine learning, and National Agriculture Imagery Program (NAIP) orthophotography for mapping general land cover across the entire state of West Virginia, USA, an area of roughly 62,000 km2. We obtained an overall accuracy of 96.7% and a Kappa statistic of …
Protoconch Enlargement In Western Atlantic Turritelline Gastropod Species Following The Closure Of The Central American Seaway, Stephanie Sang, Dana Suzanne Friend, Warren Douglas Allmon, Brendan Matthew Anderson
Protoconch Enlargement In Western Atlantic Turritelline Gastropod Species Following The Closure Of The Central American Seaway, Stephanie Sang, Dana Suzanne Friend, Warren Douglas Allmon, Brendan Matthew Anderson
Faculty & Staff Scholarship
Abstract The closure of the late Neogene interoceanic seaways between the Western Atlantic (WA) and Tropical Eastern Pacific (TEP)—commonly referred to as the Central American Seaway—significantly decreased nutrient supply in the WA compared to the TEP. In marine invertebrates, an increase in parental investment is expected to be selectively favored in nutrient‐poor marine environments as prolonged feeding in the plankton becomes less reliable. Here, we examine turritelline gastropods, which were abundant and diverse across this region during the Neogene and serve as important paleoenvironmental proxies, and test whether species exhibit decreased planktotro‐ phy in the WA postclosure as compared to …
Post-Wildfire Recovery Of An Upland Oak-Pine Forest On The Cumberland Plateau, Kentucky, Usa, Devin E. Black, Zachary W. Poynter, Claudia A. Cotton, Suraj Upadhaya, David D. Taylor, Wendy Leuenberger, Beth A. Blankenship, Mary A. Arthur
Post-Wildfire Recovery Of An Upland Oak-Pine Forest On The Cumberland Plateau, Kentucky, Usa, Devin E. Black, Zachary W. Poynter, Claudia A. Cotton, Suraj Upadhaya, David D. Taylor, Wendy Leuenberger, Beth A. Blankenship, Mary A. Arthur
Forestry and Natural Resources Faculty Publications
Background: Many forests within the southern Appalachian region, USA, have experienced decades of fire exclusion, contributing to regeneration challenges for species such as oaks (Quercus spp. L.) and pines (Pinus spp. L.), and threatening the maintenance of oak-dominated forests in the future. While the use of prescribed fire as a forest management tool is increasing within this region, there remains a lack of information on the potential role of wildfire. A wildfire within the Daniel Boone National Forest, Kentucky, USA, provided an opportunity to investigate how wildfire affected forest vegetation response.
Results: We examined the effects of fire …
Climate Evolution Across The Mid-Brunhes Transition, Aaron M. Barth, Peter U. Clark, Nicholas S. Bill, Feng He, Nicklas G. Pisias
Climate Evolution Across The Mid-Brunhes Transition, Aaron M. Barth, Peter U. Clark, Nicholas S. Bill, Feng He, Nicklas G. Pisias
School of Earth & Environment Departmental Research
The Mid-Brunhes Transition (MBT) began ∼ 430 ka with an increase in the amplitude of the 100 kyr climate cycles of the past 800 000 years. The MBT has been identified in ice-core records, which indicate interglaciations became warmer with higher atmospheric CO2 levels after the MBT, and benthic oxygen isotope (δ18O) records, which suggest that post-MBT interglaciations had higher sea levels and warmer temperatures than pre-MBT interglaciations. It remains unclear, however, whether the MBT was a globally synchronous phenomenon that included other components of the climate system. Here, we further characterize changes in the climate system across the MBT …
Coupling Between Land–Ocean–Atmosphere And Pronounced Changes In Atmospheric/Meteorological Parameters Associated With The Hudhud Cyclone Of October 2014, Akshansa Chauhan, Rajesh Kumar, Ramesh P. Singh
Coupling Between Land–Ocean–Atmosphere And Pronounced Changes In Atmospheric/Meteorological Parameters Associated With The Hudhud Cyclone Of October 2014, Akshansa Chauhan, Rajesh Kumar, Ramesh P. Singh
Mathematics, Physics, and Computer Science Faculty Articles and Research
India is vulnerable to all kinds of natural hazards associated with land, ocean, biosphere, atmosphere, and snow/glaciers. These natural hazards impact large areas and the population living in the affected regions. India is surrounded by ocean on three sides and is vulnerable to cyclonic activities. Every year cyclones hit the east and west coasts of India, affecting the population living along the coasts and infrastructure and inland areas. The extent of the affected inland areas depends on the intensity of the cyclone. On 12 October 2014, a strong cyclone “Hudhud” hit the east coast of India that caused a high …
Land Use And Land Cover Changes, And Environment And Risk Evaluation Of Dujiangyan City (Sw China) Using Remote Sensing And Gis Techniques, Biswajit Nath, Zheng Niu, Ramesh P. Singh
Land Use And Land Cover Changes, And Environment And Risk Evaluation Of Dujiangyan City (Sw China) Using Remote Sensing And Gis Techniques, Biswajit Nath, Zheng Niu, Ramesh P. Singh
Mathematics, Physics, and Computer Science Faculty Articles and Research
Understanding of the Land Use and Land Cover (LULC) change, its transitions and Landscape risk (LR) evaluation in earthquake-affected areas is important for planning and urban sustainability. In the present study, we have considered Dujiangyan City and its Environs (DCEN), a seismic-prone area close to the 2008 Wenchuan earthquake (8.0 Mw) during 2007–2018. Five different multi-temporal data sets for the years 2007, 2008, 2010, 2015, and 2018 were considered for LULC mapping, followed by the maximum likelihood supervised classification technique. The individual LULC maps were further used in four time periods, i.e., 2007–2018, 2008–2018, 2010–2018, and 2015–2018, to evaluate the …
Timing And Formation Of Linear Dunes South Of The Niobrara River Valley, North-Central Nebraska Sand Hills, Ashley K. Larsen
Timing And Formation Of Linear Dunes South Of The Niobrara River Valley, North-Central Nebraska Sand Hills, Ashley K. Larsen
Department of Geography: Dissertations, Theses, and Student Research
The Nebraska Sand Hills is a vast (7,500 square kilometer) area of grass-stabilized sand dunes. Larger dunes in the Nebraska Sand Hills formed primarily during the Late Pleistocene, but many underwent widespread reactivation during the Holocene. Recent Optically Stimulated Luminescence (OSL) dating indicates that the last major phase of reactivation in the Sand Hills was during the Medieval Warm Period, approximately 800 years ago. Nevertheless, many questions about the evolution of the dunes remain unanswered, particularly regarding the formation of linear dunes in portions of the Sand Hills.
This study seeks to understand more about the formation of linear dunes …
Geological And Environmental Sciences - 2018
Geological And Environmental Sciences - 2018
Geological and Environmental Sciences News
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Diamond Intracrystalline Stable Isotope Chemical Image Analysis By Time-Of-Flight Secondary Ionization Mass Spectrometery, Tyler J. Sundell
Diamond Intracrystalline Stable Isotope Chemical Image Analysis By Time-Of-Flight Secondary Ionization Mass Spectrometery, Tyler J. Sundell
Graduate Theses/Dissertations
The chemical resistance of diamond allows in-situ study of the diamond source regions. For a majority of gem quality diamonds, this source region is the sublithospheric mantle keel of a cratonic nuclei. Through analysis of stable isotopes, radiogenic isotopes and trace elements, diamond geochemical analyses can define chemical fluxes in the mantle keel. However, such studies require multiple methodologies for each chemical suite, high spatial resolution and analytical precision. Here, I evaluate Time-of-Flight Secondary Ionization Mass Spectrometer (ToF-SIMS) as an alternative method for diamond geochemical analyses. ToF-SIMS analysis can perform in cation and anion mode to measure the entire periodic …
Evaluating Stable Isotope And Geochronologic Techniques For Paleoclimate Reconstruction: Case Study Of The Santa Cruz Formation, Argentina, Robin B. Trayler
Evaluating Stable Isotope And Geochronologic Techniques For Paleoclimate Reconstruction: Case Study Of The Santa Cruz Formation, Argentina, Robin B. Trayler
Boise State University Theses and Dissertations
Stable isotope analysis has become the method of choice for many studies investigating the paleoecology and paleoclimate of fossil mammal faunas. While organic tissues (collagen, keratins, proteins) persist for < 105 years highly mineralized tooth enamel is resistant to alteration and degradation and faithfully preserves its isotopic composition for millions (> 106) years. Reconstructing past climates from these records relies on both understanding both micro-scale mechanisms of isotope incorporation into individual teeth, and macro-scale changes in isotope compositions over hundreds of thousands or millions of years. In this dissertation I address three questions.
First, how does the geometry and …
Investigating Smoke Aerosol Emission Coefficients Using Modis Active Fire And Aerosol Products – A Case Study In The Conus And Indonesia, Xiaoman Lu, Xiaoyang Zhang, Fangjun Li, Mark Cochrane
Investigating Smoke Aerosol Emission Coefficients Using Modis Active Fire And Aerosol Products – A Case Study In The Conus And Indonesia, Xiaoman Lu, Xiaoyang Zhang, Fangjun Li, Mark Cochrane
Global Land Surface Season Data Sets
This data set is in relation to the paper of the same title, which has been submitted to the Journal of Geophysical Research: Biogeosciences.
Instructions for viewing the data in “Readme.txt”
Groundwater Hydrogeolgy And Hydrochemistry Of Karst Springs In The Eastern Peninsula Of Fort Hood Military Installation, William Scribner Welles
Groundwater Hydrogeolgy And Hydrochemistry Of Karst Springs In The Eastern Peninsula Of Fort Hood Military Installation, William Scribner Welles
Electronic Theses and Dissertations
The eastern peninsula of Fort Hood Military Installation is underlain by a complex karst spring network. These springs are a primary water source in a protected habitat for endangered songbirds, which has only recently begun to be fully investigated. These Fredericksburg Group springs express both epigenetic and hypogenetic karst signatures. The study area is part of a paleo reef trend, a hydraulically disconnected segment of the northern section of the Edwards Aquifer. This study utilized standard ion index values, repeated measures, and principal component analyses on the chemical profiles of six perennial springs to classify spring water sources and their …
An Outcrop Based Study Of The Weches Formation In Sabine County, Texas: Investigating Its Unconventional Resource Potential Through The Study Of Stratigraphy, Sedimentology, Petrology, And Geochemistry, Talban Kantala
Electronic Theses and Dissertations
Fresh Weches Formation (Middle Eocene) exposures found in aggregate quarries in Sabine County, Texas, were sampled, measured, and logged with gamma-ray spectrometry (GRS). Sedimentology and petrology characteristics of Weches samples were analyzed through thin section, scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, and GRS Th/K ratios analyses. The source rock quality of the Weches was evaluated with geochemical techniques involving total organic carbon (TOC), Rock-Eval pyrolysis, and GRS Th/U ratios.
The Weches, in the study area, is 27.4 meters thick, and delineated into three major stratigraphic facies: an upper marginal marine prodeltaic facies (Therrill Member) comprised of silty claystones and …