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Assessment Of Snow Atmosphere Forcing During Central Idaho Atmospheric Rivers, William Rudisill 2018 Boise State University

Assessment Of Snow Atmosphere Forcing During Central Idaho Atmospheric Rivers, William Rudisill

Boise State University Theses and Dissertations

Atmospheric Rivers (AR) are globally occuring weather features and the primary mechanism through which water vapor moves from the tropics and subtropics towards the mid-latitudes, doing so at rates comparable to the world’s largest terrestrial rivers. AR that encounter mountains often cause extreme precipitation in the form of rain and snow, high winds, and flooding in many watersheds. They account for as much as 20-30% of cool season precipitation in the central Idaho Mountains. In the Northern Hemisphere, seasonal snow cover during Winter and Spring months is the most variable land surface component in space and time, and acts ...


Evaporation Depth Controls The Relationship Between Soil Water Mobility And Soil Water Isotopic Composition, John Byars Shuler 2018 Boise State University

Evaporation Depth Controls The Relationship Between Soil Water Mobility And Soil Water Isotopic Composition, John Byars Shuler

Boise State University Theses and Dissertations

Recent studies of plant water uptake assume that soil water isotopic composition can be used to infer soil water mobility. However, the strength of the relationship between mobility and isotopic composition remains poorly constrained. In addition, many ecohydrologic investigations are restricted by low sampling frequencies and insufficient soil moisture and matric potential data to support assumptions of soil water mobility. We sampled bulk soil water every 14 to 21 days in hillslope and riparian profiles during the 2016 and 2017 growing seasons in a semi-arid watershed outside Boise, ID. We collected twig samples of four tree and shrub species concurrently ...


Stratigraphic Evaluation Of The St. Joe-Boone Boundary Interval, Kinderhookian-Osagean Series, Lower Mississippian System, Tri-State Region, Southern Midcontinent, Forrest Dalton McFarlin 2018 University of Arkansas, Fayetteville

Stratigraphic Evaluation Of The St. Joe-Boone Boundary Interval, Kinderhookian-Osagean Series, Lower Mississippian System, Tri-State Region, Southern Midcontinent, Forrest Dalton Mcfarlin

Theses and Dissertations

The Lower Mississippian interval comprises a single, third-order, eustatic cycle subdivided lithostratigraphically into the St. Joe Limestone (Hopkins 1893) and overlying Boone Formation (Branner 1891, Simonds 1891) with type areas in northern Arkansas. Coeval, homotaxial limestones occur in adjacent southwestern Missouri and northeastern Oklahoma. Missouri formation names for the St. Joe interval are recognized in Arkansas as members (ascending order): Bachelor, Compton, Northview, Pierson. The Boone interval in Missouri is represented by the (ascending order): Reeds Spring, Elsey, Burlington-Keokuk undifferentiated, but utilization of those names in Arkansas is problematic. in northern Arkansas, the Boone Formation is subdivided into informal lower ...


Mapping Lower Austin Chalk Secondary Porosity Using Modern 3-D Seismic And Well Log Methods In Zavala County, Texas, David Kilcoyne 2018 University of Arkansas, Fayetteville

Mapping Lower Austin Chalk Secondary Porosity Using Modern 3-D Seismic And Well Log Methods In Zavala County, Texas, David Kilcoyne

Theses and Dissertations

Establishing fracture distribution and porosity trends is key to successful well design in a majority of unconventional plays. The Austin Chalk has historically been referred to as an unpredictable producer due to high fracture concentration and lateral variation in stratigraphy, however recent drilling activity targeting the lower Austin Chalk has been very successful. The Upper Cretaceous Austin Chalk (AC) and underlying Eagle Ford (EF) units are considered by many to act as a single hydrocarbon system, with communication between these two units largely through expulsion or dewatering fractures, extensional faults or along the AC/EF unconformity. Total porosity for the ...


The Transition From Sevier To Laramide Orogeny Captured In Upper-Plate Magmatic Structures, Eastern Transverse Ranges, Ca, Brody Friesenhahn 2018 Southern Methodist University

The Transition From Sevier To Laramide Orogeny Captured In Upper-Plate Magmatic Structures, Eastern Transverse Ranges, Ca, Brody Friesenhahn

Earth Sciences Theses and Dissertations

The onset of the Laramide orogeny is of great tectonic significance to the geologic history of the US, but the timing and nature of the shift between Sevier and Laramide tectonics remains enigmatic. The eastern Transverse Ranges of southern California provide the opportunity to observe the effects of Laramide tectonics on the mid-crust. Wide Canyon is a north/south-trending canyon in the northern Little San Bernardino Mountains of the eastern Transverse Ranges. Al-in-hornblende thermobarometry of Needy et al. (2009) yields a projected paleodepth depth of ~20 km for Wide Canyon where Cretaceous granitoids intrude metamorphic country rock of Proterozoic age ...


Recovering Legacy Geological Data Into A Geospatial Database Product: An Example From Baja California Norte, MéXico, Alexander C. Audet 2018 University of Maine

Recovering Legacy Geological Data Into A Geospatial Database Product: An Example From Baja California Norte, MéXico, Alexander C. Audet

Honors College

This project develops a workflow for the extraction of legacy geological map data using a case study in the Baja California Norte, México by four workers over forty years. This project is unique from other digitization efforts worldwide because the data were already in an unregistered vector format, instead of a raster format. Thus, the methodology used in this project took advantage of this digital format by writing arcpy scripts for use inside of ArcMap, and using database feature manipulation software, in order to streamline the data extraction process, with the goal being to develop methods for dealing with ...


The Geotraces Intermediate Data Product 2017, Reiner Schlitzer, Robert F. Anderson, Elena Masferrer Dodas, Maeve Lohan, Walter Geibert, Alessandro Tagliabue, Andrew Bowie, Gregory A. Cutter, Peter N. Sedwick, Bettina Sohst 2018 Old Dominion University

The Geotraces Intermediate Data Product 2017, Reiner Schlitzer, Robert F. Anderson, Elena Masferrer Dodas, Maeve Lohan, Walter Geibert, Alessandro Tagliabue, Andrew Bowie, Gregory A. Cutter, Peter N. Sedwick, Bettina Sohst

OEAS Faculty Publications

The GEOTRACES Intermediate Data Product 2017 (IDP2017) is the second publicly available data product of the international GEOTRACES programme, and contains data measured and quality controlled before the end of 2016. The IDP2017 includes data from the Atlantic, Pacific, Arctic, Southern and Indian oceans, with about twice the data volume of the previous IDP2014. For the first time, the IDP2017 contains data for a large suite of biogeochemical parameters as well as aerosol and rain data characterising atmospheric trace element and isotope (TEI) sources. The TEI data in the IDP2017 are quality controlled by careful assessment of intercalibration results and ...


Comparative Microbial Community Dynamics In A Karst Aquifer System And Proximal Surface Stream In Northwest Arkansas, Josue Rodriguez 2018 University of Arkansas, Fayetteville

Comparative Microbial Community Dynamics In A Karst Aquifer System And Proximal Surface Stream In Northwest Arkansas, Josue Rodriguez

Theses and Dissertations

Northwest Arkansas has well-developed karst systems, with numerous sinking streams and springs. Karst conduits make it easy for contaminants to enter groundwater systems, degrading the water quality and destroying fragile karst ecosystems. With the increase of urbanization, potential threats in the form of fecal contamination may prove to be more of a problem. The purpose of this research is to compare the difference between microbial communities within two different settings, a karst aquifer and a surface stream. The microbial communities within Blowing Spring Cave and Little Sugar Creek were detected and identified in water and sediment samples. Samples were also ...


Projected Trends In Climate Extremes In The Passaic River Basin Based On Bias-Corrected And Spatially Downscaled Global Climate Model Simulations, Archana Prasad 2018 Montclair State University

Projected Trends In Climate Extremes In The Passaic River Basin Based On Bias-Corrected And Spatially Downscaled Global Climate Model Simulations, Archana Prasad

Theses, Dissertations and Culminating Projects

Global Climate Models (GCMs) are increasingly becoming useful tools for predicting future climatic changes. These GCMs typically employ large spatial scales while municipalities may experience varied impacts at the local level. By downscaling and bias-correcting GCM outputs, more accurate predictions concerning specific regions can be made. The Multivariate Adaptive Constructed Analogs (MACA) models provide daily precipitation and temperature information for point localities by modifying coarse resolution data from GCMs to a higher spatial resolution. In this study, trends in climate extremes over the Passaic River Basin (PRB) between 1981-2005 are estimated based on three MACA models (bcc-csm1-1m, CCSM4, and MRI-CGCM3 ...


Sequence Stratigraphy Of Campanian-Maastrichtian Strata In Eastern Alabama, David Simmons 2018 The University of Southern Mississippi

Sequence Stratigraphy Of Campanian-Maastrichtian Strata In Eastern Alabama, David Simmons

Master's Theses

Eastern Alabama is an area of interest due to the transition from the Gulf Coastal Plain to the Atlantic Coastal Plain. Coastal Plain investigations have been sparse compared to research conducted in the oil rich areas down dip in the Gulf of Mexico. A sequence stratigraphic framework using the T-R cycle methodology of Embry (2002) has been established by integrating surface and subsurface lithologic data with biostratigraphic zonations into Petra ®. High sedimentation from the ancestral Chattahoochee River and lower relative sea-level formed an additional depositional sequence within the Santonian-Campanian aged Blufftown Formation in eastern Alabama. The sequence is approximately late ...


Estimating Watershed Mercury Contribution To Lake Fort Smith State Park, Arkansas, Usa, William Miles Harmon 2018 University of Arkansas, Fayetteville

Estimating Watershed Mercury Contribution To Lake Fort Smith State Park, Arkansas, Usa, William Miles Harmon

Theses and Dissertations

Mercury contamination associated with human activities poses global human health and environmental risks. A fish-consumption advisory has been in effect at Lake Fort Smith in central west Arkansas for more than a decade due to observed methylmercury concentrations in fish tissue. Lake Fort Smith is an important municipal drinking water supply and recreational resource. Water samples from the majority contributing tributary stream, Frog Bayou creek, were collected periodically, under differing hydrologic conditions in order to quantify the allochthonous mercury load delivered to the lake. Temperature, specific conductance, and turbidity data were collected and used to estimate dissolved organic carbon, methylmercury ...


Proposed Astm Standard For The Stokoe-Type Resonant Column Torsional Shear Device, Anh Tuan Tran 2018 University of Arkansas, Fayetteville

Proposed Astm Standard For The Stokoe-Type Resonant Column Torsional Shear Device, Anh Tuan Tran

Theses and Dissertations

Resonant Column Torsional Shear (RCTS) testing has become one of the most commonly used methods for determining laboratory soil stiffness and soil damping. The RCTS test has been accepted and is commonly utilized during the permitting of new nuclear facilities. However, there is still no available public standard for performing RCTS tests using the Stokoe-type device. Therefore, an ASTM standard for calibration and performance of RCTS tests using the Stokoe-type RCTS device is presented herein. Data collected using the Stokoe-type RCTS devices at the University of Arkansas (UofA) and at the Norwegian Geotechnical Institute (NGI) also aided in the development ...


Seismic Facies Mapping For Source Rock Distribution Of The Rakopi Formation In Deep-Water Taranaki Basin, New Zealand, Sidney W. Mahanay 2018 University of Arkansas, Fayetteville

Seismic Facies Mapping For Source Rock Distribution Of The Rakopi Formation In Deep-Water Taranaki Basin, New Zealand, Sidney W. Mahanay

Theses and Dissertations

The Taranaki Basin is located off the coast of the north island of New Zealand and is currently the only producing basin in New Zealand. Hydrocarbon accumulation in the Tui, Maari, and Maui fields is sourced to the Late Cretaceous and Paleogene units. Exploration of these units has extended from the continental shelf of the Taranaki Basin into the deep-water to the northwest. The Romney 3D survey and Romney–1 well are some the first public exploration projects to supply data from this area. The objective of this study is to estimate source rock quality and distribution of the Rakopi ...


Quantifying Carbon Dioxide Fluxes In The Air And Water In Blowing Springs Cave, Arkansas, Holly Young 2018 University of Arkansas, Fayetteville

Quantifying Carbon Dioxide Fluxes In The Air And Water In Blowing Springs Cave, Arkansas, Holly Young

Theses and Dissertations

Prior work has shown that the concentration of carbon dioxide (CO2) within cave atmospheres is a function of cave airflow patterns. The dynamics of CO2 within karst systems are of increasing interest as they can control periods of precipitation or dissolution in speleothems and influence potential interpretations of paleoclimate records. Similarly, CO2 is an important driver of speleogenesis, and air-water CO2 dynamics can control patterns of cave passage evolution. Karst also plays an uncertain role in the global carbon cycle and understanding CO2 dynamics within karst systems will aid the development of carbon budgets. Here, a monitoring station was deployed ...


Analysis Of The Parkway Drive Landslide, North Salt Lake, Ut, Brianna V. Hill 2018 Utah State University

Analysis Of The Parkway Drive Landslide, North Salt Lake, Ut, Brianna V. Hill

All Graduate Plan B and other Reports

On August 5th, 2014, a hillside failed behind a North Salt Lake City, UT neighborhood threatening several homes. Aerial Photography, Digital Elevation Models (DEM), geochemistry, rain gage and seismic data were used to test the influence of contributing factors in this landslide failure. Aerial photographs available from 1993 to present were examined for signs of tension cracks suggesting impending ground motion, as well as documentation of human modification along the hillslope. Repeat DEM analysis of elevation and slope of the hillside before and after the slide were examined to characterize the pre-failure hillslope and subsequent landslide. Geochemical analyses were ...


Spatial And Temporal Trends Of Mining-Related Lead-Zinc Sediment Contamination, Galena River Watershed, Sw Wisconsin-Nw Illinois, Dylan Alexander King 2018 Missouri State University

Spatial And Temporal Trends Of Mining-Related Lead-Zinc Sediment Contamination, Galena River Watershed, Sw Wisconsin-Nw Illinois, Dylan Alexander King

MSU Graduate Theses

Alluvial sediments within the Galena River Watershed were severely contaminated with heavy metals by historical zinc (Zn) and lead (Pb) mining operations during the early 1800s until 1979. Since the mines closed, there have been efforts to remediate on-site mine waste. However, the effectiveness of these efforts to reduce metal concentrations in stream sediments is unknown. This study compares present-day (2017) contamination trends in the Galena River Watershed to trends reported 25 years ago. A total of 415 sediment/soil samples were collected and analyzed using X-ray florescence spectrometry to determine sediment metal concentrations. The highest concentrations of zinc measured ...


Nutrient Transport And Storage In A Karst Spring-Reservoir System During Baseflow, Missouri Ozarks, Heather A. Moule 2018 Missouri State University

Nutrient Transport And Storage In A Karst Spring-Reservoir System During Baseflow, Missouri Ozarks, Heather A. Moule

MSU Graduate Theses

Urban and agricultural land uses are important sources of nitrogen and phosphorus which, if in excess, can cause eutrophication in lakes and rivers. There have been few studies of nutrient transport and storage in karst spring and reservoir connected stream systems draining the Missouri Ozarks. This study aims to link the baseflow nutrient contributions of Sanders Spring to downstream reservoir outflow and the Headwaters South Dry Sac River Watershed in Springfield, Missouri. Water samples were collected seasonally and analyzed for total nitrogen (TN), total phosphorus (TP), and several other water quality parameters. Discharge was also monitored to calculate water and ...


Fault-Adjacent Damage At The Base Of The Seismogenic Zone And Seismic Anisotropy Of Fold Structures, Won Joon Song 2018 University of Maine

Fault-Adjacent Damage At The Base Of The Seismogenic Zone And Seismic Anisotropy Of Fold Structures, Won Joon Song

Electronic Theses and Dissertations

While earthquakes represent a major hazard to life and property, there are a number of open questions about how earthquake faults operate at depth, and how the energy released by earthquakes travels as elastic waves through Earth’s complexly deformed crustal rocks. The aims of my dissertation are to explore (a) the extent of co-seismic damage in an ancient earthquake fault exhumed from great depths, (b) the deformation processes and mechanics of the fault at depth during earthquake cycles, and (c) the role of different rock structures in determining the velocities of seismic waves.

When tectonic plates collide, deformation tends ...


Electron Backscatter Diffraction (Ebsd) Study Of Seven Heavily Metamorphosed Chondrites: Deformation Systematics And Variations In Pre-Shock Temperature And Post-Shock Annealing, Alexander M. Ruzicka, Richard C. Hugo 2018 Portland State University

Electron Backscatter Diffraction (Ebsd) Study Of Seven Heavily Metamorphosed Chondrites: Deformation Systematics And Variations In Pre-Shock Temperature And Post-Shock Annealing, Alexander M. Ruzicka, Richard C. Hugo

Geology Faculty Publications and Presentations

We used electron backscatter diffraction (EBSD) methods to study the crystallography of olivine and other minerals in seven heavily metamorphosed (petrographic type 6 or 6/7) but variably shocked ordinary chondrites from the H (Kernouvé, Portales Valley), L (Leedey, Bruderheim, Morrow County, Park) and LL (Miller Range (MIL) 99301) groups. MIL 99301 contains a large clast that was analyzed separately. Mesoscale (EBSD) data support and extend inferences based on microscale (TEM) observations and provide good evidence that chondrites were shock-deformed at different temperatures and were variably annealed (sintered) after deformation. Various EBSD deformation intensity metrics adequately and quantitatively represent olivine ...


Geomechanical Modelling Of Induced Seismicity, Bodi Zhao 2018 The University of Western Ontario

Geomechanical Modelling Of Induced Seismicity, Bodi Zhao

Electronic Thesis and Dissertation Repository

In recent years, there has been a dramatic increase in seismicity (earthquakes) due to anthropogenic activities related to the unconventional oil and gas exploration in the Western Canada Sedimentary Basin (WCSB) and the central U.S. There are compelling evidences that hydraulic fracturing and wastewater injection operations in those areas play a key role in induced seismicity. To better understand the physical mechanisms involved, this thesis aims to explore the mechanisms responsible for occurrence of induced earthquakes: mainshock-aftershock triggering mechanism and poroelastic response. In the first approach, the obtained results indicate the relationship between the Coulomb stress changes after 4 ...


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