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Articles 61 - 90 of 1193
Full-Text Articles in Earth Sciences
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 …
Evaluation Of A Sequential Pond System For Detention And Treatment Of Runoff At Skypark, Santa's Village, Elizabeth Caporuscio
Evaluation Of A Sequential Pond System For Detention And Treatment Of Runoff At Skypark, Santa's Village, Elizabeth Caporuscio
Electronic Theses, Projects, and Dissertations
Understanding the extent to which human activities impact surface water resources has become increasingly important as both human population growth and related landscape changes impact water quality and quantity across varying geographical scales. Skypark, Santa’s Village is a 233.76-acre tourism-based outdoor recreation area located in Skyforest, California residing within the San Bernardino National Forest. The park is situated at Hooks Creek, the headwaters of the Mojave River Watershed, and is characterized by a diverse landscape that includes forest cover and human development, including impervious surfaces, a restored meadow, and recreational trails. In 2016, Hencks Meadow was considered degraded by human …
Simulation Of Climate Across The Permian-Triassic Boundary With A Focus On Phytogeographical Data Analysis, Mitali Dinesh Gautam
Simulation Of Climate Across The Permian-Triassic Boundary With A Focus On Phytogeographical Data Analysis, Mitali Dinesh Gautam
Earth & Environmental Sciences Theses - Archive
The present study aims at reconstructing the paleoclimate across the Permian-Triassic Boundary (PTB, 251.9 ± 0.024 Ma) which encompasses one of the major mass extinction events of the Earth’s history. Results are analyzed from sensitivity experiments that have been previously been carried out with a community climate system model (CCSM3) for 4x CO2 higher than the pre-industrial levels of 280 ppmv, 12.7x CO2 and 12.7x CO2 with a lower cloud cover . This study attempts to reconstruct the climate using the floristic patterns derived from plant-fossil data. Finally, simulated biomes are compared with data-derived biomes, in order to validate the …
Regional Sulfur Isotope Study Of The Vms Deposits In The Penokean Volcanic Belt, Nicholas M. Moleski
Regional Sulfur Isotope Study Of The Vms Deposits In The Penokean Volcanic Belt, Nicholas M. Moleski
Masters Theses
The Penokean Volcanic Belt (PVB), located in northern Wisconsin and Upper Peninsula, Michigan hosts several volcanogenic massive sulfide deposits (VMS) including the well-known deposits of Flambeau and Crandon. The host rocks of the VMS deposits are Paleoproterozoic in age overlying Archean age basement rocks. This study provides δ34S (VCDT) values for the following deposits within the PVB; (1) Eisenbrey, (2) Schoolhouse, (3) Bend, (4) Flambeau, (5) Reef, (6) Horseshoe, and (7) Back Forty, and explains the distribution of δ34S values in the region.
The study reveals tight ranges of δ34S values for each deposit …
Metal Contamination And Food Web Changes Alter Exposure To Upper Trophic Levels In Upper Blackfoot River Basin Streams, Montana, Jack E. Landers, Sean Sullivan, Lisa Eby, Andrew C. Wilcox, Heiko Langner
Metal Contamination And Food Web Changes Alter Exposure To Upper Trophic Levels In Upper Blackfoot River Basin Streams, Montana, Jack E. Landers, Sean Sullivan, Lisa Eby, Andrew C. Wilcox, Heiko Langner
Geosciences Faculty Publications
Reduced invertebrate abundance and diversity are common responses to metals contamination in mining-impacted streams. The resulting changes in community composition may have implications for metals accumulation and transfer through the food web. We investigated how changes in invertebrate community composition (abundance, species richness, and food web complexity) influence metals bioaccumulation and exposure risk to upper trophic levels along a contamination gradient in the upper Blackfoot River Basin, Montana. Invertebrate species richness exhibited the strongest decline with increasing sediment metals concentrations, driven by the loss of metals-sensitive taxa. These changes in invertebrate community composition resulted in a decline in the proportion …
Managing For Vegetation Heterogeneity On Rangelands: An Exploration Of Rancher Attitudes, Stephanie Marie Kennedy
Managing For Vegetation Heterogeneity On Rangelands: An Exploration Of Rancher Attitudes, Stephanie Marie Kennedy
School of Natural Resources: Dissertations, Theses, and Student Research
Grasslands provide food, fiber, and numerous ecosystem services to human populations as well as habitat for wildlife. They are also some of the most endangered ecosystems in the world because of their productive soils and open topography. This problem is exacerbated by the accelerating conversion of grassland to cropland and encroaching trees and shrubs. The quality of remaining grasslands will be of increasing importance because of the biodiversity and vital ecosystem services they provide. Heterogeneity is a term specific to rangeland science that is illustrative of grassland health. Grassland species require very specific and differing habitats and without the variation …
The Biological Significance And Utility Of Feeding By Dermestes Maculatus, Braymond Adams
The Biological Significance And Utility Of Feeding By Dermestes Maculatus, Braymond Adams
School of Natural Resources: Dissertations, Theses, and Student Research
With their efficient feeding habits and tolerance to very low moisture and humidity, beetles in the Family Dermestidae are especially adapted to variable environments and habitats. Dermestid cultures have been in use since 1922 in cleaning tissue and flesh from bones, and proven benefit in multiple fields, including zoology, ornithology, and forensics. Dermestid feeding behaviors when coupled with known life stage and insect succession information aids in providing significant entomological evidence. However, the feeding activities of insects, like those of vertebrate scavengers and predators, change remains and may leave artifacts that can be sometimes be difficult to assign to a …
Assessing Land Deformation And Sea Encroachment In The Nile Delta: A Radar Interferometric And Modeling Approach, Esayas Gebrekidan Gebremichael
Assessing Land Deformation And Sea Encroachment In The Nile Delta: A Radar Interferometric And Modeling Approach, Esayas Gebrekidan Gebremichael
Dissertations
Many of the deltas of the world are experiencing land deformation, subsidence or uplift of landmass, due to natural or anthropogenic causes, or a combination of both processes and causes. These deltaic settings are densely populated and border some of our world’s largest water bodies (oceans and seas). The land deformation, especially the subsidence component, when combined with the climate change-induced sea level rise, coastal erosion, and other anthropogenic drivers, will undoubtedly impact the population and economy of coastal areas of deltas. For the Nile Delta of Egypt, the land deformation processes and the factors that control the deformation processes …
Volcano Infrasound Monitoring With Applications For Statistical Forecasting Of Explosions At Sakurajima (Japan), Matthew R. Vonlintig
Volcano Infrasound Monitoring With Applications For Statistical Forecasting Of Explosions At Sakurajima (Japan), Matthew R. Vonlintig
Boise State University Theses and Dissertations
Volcanic eruptions are powerful natural phenomena that often occur unpredictably in time and magnitude. Nearby communities are put at risk during volcanic unrest; however, when hazards are well understood and clearly defined risk can be mitigated. This thesis addresses the problem of forecasting the likelihood of future explosive volcanic behavior by monitoring ongoing eruptive history with infrasound. I parameterize inter-event temporal behavior to determine the eruption controlling processes is material failure opposed to changes in magma and volatile supply.
I analyze data from Sakurajima, a type-example open volcano, using two local (4 km from the vent) microphone arrays, which recorded …
Cross-Scale Interactions Between Atmospheric And Hydrologic Processes In A Topographically Complex, Snow-Dominated Watershed As Revealed Through An Integrated Hydrologic Model, Miguel A. Aguayo Arias
Cross-Scale Interactions Between Atmospheric And Hydrologic Processes In A Topographically Complex, Snow-Dominated Watershed As Revealed Through An Integrated Hydrologic Model, Miguel A. Aguayo Arias
Boise State University Theses and Dissertations
In much of the world, water for agricultural, domestic, and hydroelectric power generation uses are derived from snow-dominated mountain basins. In these regions, water management requires accurate and timely knowledge of runoff generation by snowmelt. This information is used to plan reservoir releases for downstream users and is generated by models of biophysical processes associated with varying degrees of fidelity to physical processes and/or spatial heterogeneities. The large variability in the characteristic spatial and temporal scales of atmospheric forcings, land-surface water and energy balance, and groundwater flow contribute to significant uncertainties in resolved hydrologic states and fluxes. Underlying sources of …
Pressure Waves And Tephra Dispersal From Volcanic Explosions: Models, Observations, And Instrumentation, Jacob Fortner Anderson
Pressure Waves And Tephra Dispersal From Volcanic Explosions: Models, Observations, And Instrumentation, Jacob Fortner Anderson
Boise State University Theses and Dissertations
Real-time study of erupting vents is important for both monitoring and scientific purposes; because direct in-situ study of erupting vents is impractical, our best tools for studying eruptions in real time involve monitoring eruptive products and waves that travel far from the volcano. The atmosphere is a particularly advantageous medium for studying propagation and transport of volcanic waves and products: acoustic waves pass through it with minimal scattering, particles follow predictable trajectories, and the atmospheric structure that affects both is well-monitored. Analyses of acoustic waves and tephra deposits can provide important information on eruptions including total explosive energy, volume, and …
Correlating The Spatial Distribution Of Snow Depth To Forest Canopy Parameters Derived From Terrestrial Laser Scans, Zachary Uhlmann
Correlating The Spatial Distribution Of Snow Depth To Forest Canopy Parameters Derived From Terrestrial Laser Scans, Zachary Uhlmann
Boise State University Theses and Dissertations
In nonpolar, cold climate zones, snow accounts for 17% of the total terrestrial water storage. Estimating the amount of water stored in a snowpack, the snow water equivalent (SWE), and its spatial distribution is crucial to providing water managers with parameters to predict runoff timing, duration and amount. Reservoir management, hydropower and flood forecasting depend on SWE estimates. While landscape features such as aspect and slope are dominant controls on radiative energy in non-forested areas, forest cover can shift the energy balance composition from turbulent exchange in exposed, windy sites to primarily radiative inputs in the subcanopy. Additionally, forest cover …
Investigating The Annual Water Balance Of A High-Altitude Watershed Using Near-Real Time Lidar Data Integration Into A Physically Based Snowmelt Model, Andrew R. Hedrick
Investigating The Annual Water Balance Of A High-Altitude Watershed Using Near-Real Time Lidar Data Integration Into A Physically Based Snowmelt Model, Andrew R. Hedrick
Boise State University Theses and Dissertations
Knowledge of the amount of water stored in the mountain snowpack is crucial for flood prevention, drought mitigation, and energy production in the Western United States. In modeling terms, the most important component of the hydrologic water balance is the precipitation input to the system. Determining where and how much precipitation falls in mountain catchments, however, is the most difficult problem with regards to closing the water balance. The work presented in this dissertation details the modeling portion of the NASA Airborne Snow Observatory (ASO) using the iSnobal physically based snow model. This combination of remote sensing and modeling at …
Stable Isotope Geochemistry Of Bioapatite, Amanda E. Drewicz
Stable Isotope Geochemistry Of Bioapatite, Amanda E. Drewicz
Boise State University Theses and Dissertations
The Cenozoic Era was a time period where dynamic shifts in climate created for both warm-wet greenhouse environments of the mid-Miocene Climatic Optimum (MMCO), and cool-dry, glacial periods of the late Pleistocene. The Cenozoic is close to our own time period, and although past climate reconstructions cannot be used as direct analogs for future climate change, understanding previous environmental responses can help inform policy surrounding future climate change. Presented here are climate reconstructions of the interior western United States, from two different geologic time periods. Each had a different climate, that differed greatly from modern day environments. The use of …
Post-Fire Variation In Aeolian Deposition In The Northern Great Basin, Clayton Roehner
Post-Fire Variation In Aeolian Deposition In The Northern Great Basin, Clayton Roehner
Boise State University Theses and Dissertations
Aeolian processes play a significant role in the redistribution of sediment and nutrients in sparsely vegetated sagebrush-steppe ecosystems. When fire is introduced to the landscape, decreased surface roughness and associated threshold friction velocities allow for the increased mobility of surface sediments and burnt organic material, mobilizing previously stable material. Once material is entrained, interactions between a dynamic atmosphere and complex topography control the spatial distribution of aeolian deposition over a landscape. Given the significant impact of fire on aeolian processes in semi-arid deserts, we posit that postfire aeolian redistribution of material is an important control on the spatial variability of …
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 …
Exploring Potential Water-Ice Occurrence On Asteroid 4 Vesta Using Orbital Radar Observations By The Dawn Mission, Elizabeth M. Palmer
Exploring Potential Water-Ice Occurrence On Asteroid 4 Vesta Using Orbital Radar Observations By The Dawn Mission, Elizabeth M. Palmer
Dissertations
Airless, differentiated planetesimals in the inner solar system were presumed to have been depleted of most of their initial volatile content during formation. However, water-ice has been discovered at the lunar poles (Li et al., 2018), is inferred to exist in polar craters on Mercury (e.g., Butler, Slade & Muhleman, 1993, and suggested to survive beneath the dusty regolith of objects in the main asteroid belt if buried at sufficient depths—at least one meter for small-bodies in the outer main-belt (Schorghofer, 2008). Hence, the study of volatile occurrence, past or present, on airless, desiccated small-bodies provides insights into the timing, …
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”
Measuring Connective Capacity Throughout The Gulf Of Mexico Fishery Management Network, Anthony Rocha Lima
Measuring Connective Capacity Throughout The Gulf Of Mexico Fishery Management Network, Anthony Rocha Lima
Theses and Dissertations
The Gulf of Mexico provides substantial resources along its 1,680-mile coastline, spanning 5 U.S. states and providing millions of pounds of seafood and hundreds of millions in revenue annually. Continued success of the fishery relies on the ability of a large, complex, multiagency network to find the best solutions to balance the needs of humans, as well as ensure long-term sustainability. Organizations with varying objectives require effective communication when addressing intricate ecosystem-based management topics such as endangered species and regional economies.
To better understand the connectivity within the Gulf fishery management network, an IRB reviewed survey was dispersed to the …
Physical And Chemical Controls On Suffosion Development In Gypsic Soil, Culberson County, Texas, Jonah Morris
Physical And Chemical Controls On Suffosion Development In Gypsic Soil, Culberson County, Texas, Jonah Morris
Electronic Theses and Dissertations
In the Gypsum Plain, suffosion processes have encouraged road failure through dissolution and transport of gypsic soils; however, no prior research has been conducted within the Delaware Basin in regard to these processes. These phenomena were evaluated in both field and laboratory settings in order to assess the parameters of suffosion development associated with Ranch to Market (RM) 652 in Culberson County, Texas, where infrastructure extends across Castile and Rustler strata. Field studies simulated surficial ponding in various gypsic soils and correlated suffosion potential with soil composition and thickness. Soluble fractions of gypsic soils were delineated through geochemical analyses, further …
Methanogens, Plausible Extraterrestrial Life Forms On Mars, And Their Tolerance To Increasing Concentrations Of Illite Clay, Chandler Kern
Methanogens, Plausible Extraterrestrial Life Forms On Mars, And Their Tolerance To Increasing Concentrations Of Illite Clay, Chandler Kern
Biological Sciences Undergraduate Honors Theses
Methanogens, some of Earth’s most primitive prokaryotic organisms, are candidates for possible life forms capable of inhabiting Mars. Specifically, four different species (Methanobacterium formicicum, Methanococcus maripaludis, Methanosarcina barkeri, Methanothermobacter wolfeii) were analyzed for their tolerance to the presence of illite clay. Illite is a crystalline mineral that has been identified from regions of Mars’s surface. Results indicated that all four species grew with some success in the illite at different concentrations. This experimentation with methanogens’ abilities to survive and reproduce in the presence of illite allows for a more accurate understanding of the potential capability of microbial …
Breeding For Resilience To Increasing Temperatures: A Field Trial Assessing Genetic Variation In Soft Red Winter Wheat, Kathleen Russell, David Van Sanford
Breeding For Resilience To Increasing Temperatures: A Field Trial Assessing Genetic Variation In Soft Red Winter Wheat, Kathleen Russell, David Van Sanford
Plant and Soil Sciences Faculty Publications
Breeding for resilience to climate change is a daunting prospect. Crop and climate models tell us that global wheat yields are likely to decline as the climate warms, causing a significant risk to global food security. High temperatures are known to affect crop development yet breeding for tolerance to heat stress is difficult to achieve in field environments. We conducted an active warming study over two years to quantify the effects of heat stress on genetic variation of soft red winter (SRW) wheat (Triticum aestivum L.). Forty SRW cultivars and breeding lines were chosen based on marker genotypes at …
Impacts Of Habitat Attributes And Community Gardens On Urban Bird Communities, Samuel Glenn Ortiz
Impacts Of Habitat Attributes And Community Gardens On Urban Bird Communities, Samuel Glenn Ortiz
Theses and Dissertations
The Rio Grande Valley of Southern Texas is a major agricultural region yet has some of the highest hunger rates in the USA. Urbanization and agriculture affect biodiversity, which is well studied, but little is known about how agriculture affects biodiversity in urban areas. We investigated how different urban attributes, including those related to urban farming, impact bird communities in Brownsville and Harlingen, TX, and compared sites that have community gardens to those that do not. To study three key urban habitat characteristics, we identified sites that exhibited all possible combinations of these factors, quantified land cover classes related to …
Longitudinal And Temporal Comparison Of Beach Sand On The Rio Grande Delta System, Samantha B. Moore
Longitudinal And Temporal Comparison Of Beach Sand On The Rio Grande Delta System, Samantha B. Moore
Theses and Dissertations
The Rio Grande is the 5th longest river in North America and defines a significant extent of the United States-Mexico border. It extends for 2830 km from its headwaters in the Rocky Mountains of Colorado to the Gulf of Mexico. The Rio Grande is fed by streams from the Sangre de Cristo Mountains, the Rio Conchos, the Pecos River, runoff from the Sacramento Mountains area, Devils River, the Rio Salado, and the Rio San Juan. This study addresses how the composition of sand forming the Rio Grande river delta into the Gulf of Mexico at Boca Chica Beach is changed …
Hydrogeologic Framework Studies Of Portions Of The Niobrara River, Douglas R. Hallum, Steven S. Sibray, Leslie M. Howard
Hydrogeologic Framework Studies Of Portions Of The Niobrara River, Douglas R. Hallum, Steven S. Sibray, Leslie M. Howard
Conservation and Survey Division: Faculty and Staff Publications
The Nebraska Department of Natural Resources (NeDNR) and Upper Niobrara-White Natural Resources District (UNWNRD) expressed interest in improving understanding and their ability to effectively manage water resources in and around a particular reach of the Niobrara River. Aquifer-thickness contours mapped by the Conservation and Survey Division (CSD) indicate that the principle aquifer has zero thickness in this area. Additionally, the statewide geologic bedrock map produced by CSD shows non-aquifer strata of the White River Group along the same reach, and this setting is consistent with the designation of an “aquifer absent area,” as in the present document. Water-management policy development …
Holocene Formation And Evolution Of Horn Island, Mississippi, Usa, Nina Gal
Holocene Formation And Evolution Of Horn Island, Mississippi, Usa, Nina Gal
Master's Theses
Horn Island, one of the most stable barriers along the Mississippi-Alabama chain, provides critical habitat, helps regulate estuarine conditions in the Mississippi Sound, and reduces wave energy and storm surge for the mainland. This study integrates 2,200 km of high-resolution geophysics, 35 sediment cores, and 15 radiocarbon ages to better understand the formation and evolution of the island in response to sea-level rise, storms, and antecedent geology. The Biloxi and Pascagoula incised valleys converge at Horn Island and have played a profound role in the evolution of the system. Within the incised valleys, numerous shallow paleochannels between 4 and 9 …
Crustal Composition Beneath Southern Idaho: Insights From Teleseismic Receiver Functions, Thomas Branson Harper
Crustal Composition Beneath Southern Idaho: Insights From Teleseismic Receiver Functions, Thomas Branson Harper
Boise State University Theses and Dissertations
Receiver functions derived from teleseismic earthquakes contain seismic amplitude and velocity information that relate to compositional changes within the Earth’s crust and upper mantle. The receiver function waveform is a combination of P-S converted waves that have reverberated within the lithosphere. Although the largest seismic velocity boundary is found at the base of the crust, I explore the use of lower amplitude receiver function arrivals that represent smaller velocity contrasts within the crust. In my thesis, I calculate and model receiver functions via a Metropolis algorithm approach to extract seismic velocity distributions in the lithosphere. I use the results to …
Compositional And Thermodynamic Variability In A Stratified Magma Chamber: Evidence From The Green Tuff Ignimbrite (Pantelleria, Italy)., Katarzyna M. Liszewska, John C. White, Ray Macdonald, Bogusław Bagiński
Compositional And Thermodynamic Variability In A Stratified Magma Chamber: Evidence From The Green Tuff Ignimbrite (Pantelleria, Italy)., Katarzyna M. Liszewska, John C. White, Ray Macdonald, Bogusław Bagiński
EKU Faculty and Staff Scholarship
The Green Tuff Ignimbrite, Pantelleria, is compositionally zoned from pantellerite at the base to comenditic trachyte at the top, the variation apparently representing an inverted vertical zonation in the pre-eruptive reservoir. The main phenocryst assemblages are alkali feldspar + olivine + clinopyroxene + ilmenite + apatite in the trachytes and alkali feldspar + aenigmatite + clinopyroxene + quartz in the rhyolites. Thermodynamic modelling indicates that the temperature range was ~900–700°C, fO2 FMQ –1.5 to FMQ –0.5 (where FMQ is fayalite–magnetite–quartz buffer) and aSiO2 (relative to quartz saturation) 0.74–1.00. Melt water contents ranged from ~1wt % in the trachytes to ~4wt …
Improving Sinkhole Mapping Using Lidar Data And Locating Sinkhole Hotspots In Johnson City, Tn, Kingsley Fasesin
Improving Sinkhole Mapping Using Lidar Data And Locating Sinkhole Hotspots In Johnson City, Tn, Kingsley Fasesin
Electronic Theses and Dissertations
Predicting infrastructure damage and economic impact of sinkholes requires high accuracy mapping distribution and development. The study mapped sinkholes and sinkhole hotpsots in Johnson City, TN using LiDAR-derived Digital Elevation Model (DEM) and a database of known sinkholes which were matched to LiDAR-derived depressions. For all matched depressions (n = 404), three metrics were calculated: circularity index, ratio of length to width of the Minimum Bounding Rectangle (MBR) and percent coverage of the MBR by the depression, and 3,634 new sinkholes were identified. Newly developed hotspots were identified in north Johnson City and other areas in the south near the …
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 …