Physical Sciences and Mathematics Commons^™

An Integrated Machine Learning Geological Field Tool In The Age Of Big Data And Drones, Guillermo Vargas

Open Access Theses & Dissertations

Unmanned aerial vehicles (UAVs) and machine learning are relatively new research tools in the geosciences that can be used to collect and analyze large data sets rapidly. We combine the power of rapid data collection using unmanned aerial vehicles with machine learning algorithms to develop a field-based system to identify targeted geological features. For data collection, we have used a commercial-grade UAV which carried visible-wavelength and multispectral (visible- infrared) cameras. We analyzed the data with machine learning and machine vision algorithms that can classify rock units exposed in a field area. We have identified algorithms that in previous literature have …

Geostatistical And Geospatial Distribution Of Multiple Metallic Elements In Agricultural Regions Of The Mid-Continental Usa, Najwah Alssaeidi Ahmed Almesleh

Open Access Theses & Dissertations

Regional geochemical mapping constitute the chemistry of the surface of the earth in a large scale and relatively low sample density. It is widely accepted scientific activity and man uses some cases to identify contamination. In the present study, data present in national geochemical survey database was used to investigate the chemical loading loading of the agricultural soil. In the mid-continent region of the United States. Several traditional parameters were used mainly the enrichment factor (EF), and geoaccumulation index (I geo). Total chemical influence (TCI) maps were used to guide sampling. In addition, regional trace element chemistry of bedrock was …

Magnetotelluric Analysis Of Central Kenya Kenyan Rift Volcanoes For Geothermal Development, Anna Wairimu Mwangi

Open Access Theses & Dissertations

Abstract

High temperature geothermal resources are vast along rift margins because of emplacement of magma in shallow crust. This is the case along the Kenyan Rift valley also known as the Gregory Rift. It is the Eastern arm of the East African rift and a chain of volcanoes along the rift graben characterizes it. We use (MT) magnetotelluric method to image beneath the peralkaline province of the Kenya Rift i.e. Olkaria, Eburru, Badlands, and Longonot volcanoes. The resistivity structure shows active geothermal activity happening at the upper 3km from the subsurface as evidenced by low resistivity cap rock comprised of …

Determing Fault Location Within An Active Rift Basin Using Gravity Analysis To Determine Fault Movemnet And Effect On Water Recharge, Mark Andrew Ornelas

Open Access Theses & Dissertations

The growth of the El Paso, TX and Ciudad Juárez, Chihuahua, metropolitan area has increased reliance of groundwater pumping from the Hueco Bolson. With growing demands for water and recharge of the bolson not occurring at a fast enough rate, water storage within the bolson is beginning to diminish. My study focuses on locating and understanding how faults interact with water flow into the basin and how they aid in storing water on the northwestern side of the bolson. Previous studies in the northernmost part of my study area have delineated a series of faults that predominantly trend northwest-southeast. In …

Characterization And Geochemistry Of Carbonate Caprock Associated With The Gypsum Valley Salt Wall, Paradox Basin, Colorado: Implications For Understanding Lateral Caprock Emplacement, Piper Lee Poe

Open Access Theses & Dissertations

On the northeastern side of Gypsum Valley salt wall in the Paradox Basin of Colorado, discontinuous exposures of layered gypsum and carbonate rocks were previously mapped as the contact between diapiric Paradox Formation and marine limestone of the Pennsylvanian Honaker Trail Formation. Utilizing new and existing mapping, petrographic and isotopic geochemical analyses, this study reinterprets this zone to represent lateral gypsum and carbonate caprock that formed in the Triassic during passive rise of the Gypsum Valley salt wall. Gypsum Valley lateral carbonate caprock can be distinguished from Pennsylvanian and Permian depositional carbonate strata exposed elsewhere on the salt wall by …

Geophysical Investigations Of Southcentral Alaska, Felix Dziedzorm Ziwu

Open Access Theses & Dissertations

The Castle Mountain Fault (CMF) is the closest (<50 km) active fault to Anchorage, Alaska and is known to be capable of producing earthquakes of magnitude 7.0 â?? 7.1. While several mapping and trenching studies have been conducted along the CMF, geophysical investigations along the fault zone have been limited. We use over 700 recently collected, closely spaced gravity observations, in addition to existing regional gravity, aeromagnetic, seismic reflection, well log data, and geologic information, to develop new 2D models of the deeper structure of the CMF system. We developed four 2D integrated forward models across the Castle Mountain Fault. These models indicate differences between the western and eastern segments of the Castle Mountain Fault. The models show a thick sequence of Tertiary to Mesozoic sediments overlying the Peninsular terrane basement at varying depths within the area. We identified two main intrusive granitic rocks based on the varying susceptibilities. These granitic rocks share a possible fault contact with the Mesozoic sedimentary rocks. The model also shows that the CMF cuts through the Mesozoic sediments at depth. These rocks can create strong coupling along the fault and with the decreasing eastward angle of subduction, it is highly for fluid migration to the eastern edge of the subducting Yakutat microplate. Seismic events plotted along the profiles supports the Holocene motion along the western CMF (WCMF) and indicates a deeper extent of the CMF into the crust. The eastern CMF shows high rate of deformation based on the structures associated with the Mesozoic rocks.

Effects Of Increasing Deciduous Shrub Litter On Ecosystem Functioning In Alpine Tundra, Alejandro Emmanuel Benhumea

Open Access Theses & Dissertations

Rising temperatures due to global warming have resulted in rapid environmental changes in northern environments, resulting in an increase in deciduous shrub growth which has the potential to alter soil ecosystem properties and processes. In order to address some potential mechanisms by which shrubs alter ecosystem properties and processes, we designed an experiment which separated the effects of physical shrub presence and the effects of litter quantity in a fully factorial experiment on a north facing alpine plateau in the southwest Yukon, Canada. Specifically, we asked the following questions: What are effects of shrub litter, independent of shrub presence, on …

Mapping Complex Fold-Thrust Systems In An Inverted Rift Basin: Indio Mountains, West Texas, Samantha Ramirez

Open Access Theses & Dissertations

This study reports on new geologic mapping in the southern Indio Mountains of west Texas, where minimal research has been done since development of modern fold-thrust belt concepts. This study integrated an analysis of structure and the stratigraphy of the region. A stratigraphic column of the middle Cretaceous upper Yucca Formation was measured to 1) compare the lithology to that of the section previously measured in the hanging wall of the Squaw Peak thrust in the footwall of the Indio normal fault, 2) create informal members in the formation to aid mapping; and 3) identify previously unmapped structures in the …

Geophysical Studies Of Southwestern Part Of The North American Craton, Luis Martin Sandoval Magallanes

Open Access Theses & Dissertations

The present study, based on combined geophysical, geochronological and isotopic data identifies a cratonic block which we call the Western Chihuahua-Mesa Central megablock (WCMB) in northern Mexico. New Bouguer and isostatic gravity anomaly maps revealed a conspicuously distinct, spatially-extensive gravity minima over a region extending from north western Chihuahua to as far south as the Mesa Central (MC). This region can be differentiated from the surrounding mobile belts with significantly higher gravity anomaly values. Gravity modeling combined with sparse seismically determined crustal thickness estimates indicate that the proposed WCMB region has crustal thicknesses ranging from 38 to 42 km. The …

Back Calculation Of Intelligent Compaction Data For Mechanical Properties Of Soil System, Afshin Gholamy

Open Access Theses & Dissertations

For national economy, it is very important to have a reliable infrastructure. Because of this, all over the world, new roads are constantly being built and old roads are being maintained and, if necessary, expanded and/or repaired. Building a good quality road is very expensive, it costs several million dollars per kilometer. It is therefore crucial to make sure that the newly built and newly repaired roads are sufficiently stiff - so that they can withstand the predicted volume of traffic for a sufficient number of years. Current methods of estimating the stiffness are time-consuming and labor-consuming. The most accurate …

A Machine Learning Approach To Rendering 3d Stratigraphic Models Of The Hueco Bolson, Western Texas And Northern Mexico, Joel Gerardo Castro

Open Access Theses & Dissertations

Data visualization is an effective way to analyze large amounts of spatial information to identify correlations, trends, outliers, and patterns. In this Thesis I test the application of supervised machine learning algorithms to render a series of 3D visualizations designed to highlight general traits of the Hueco Bolson, a geologic basin located east of the Franklin Mountains in far west Texas and northern Mexico. A geologic basin is one of the most common inland places where sediments are collected. The geology of basins is of much interest to geophysicists, hydrologists, paleontologists, and oil prospectors. Here the task of 3D geologic …

Onshore-Offshore Velocity Models North Of The Mendocino Triple Junction In Northern California, Alan Jacquez

Open Access Theses & Dissertations

The Mendocino Triple Junction (MTJ) marks the boundary where the Gorda plate, North American Plate, and Pacific Plate meet, separating the Cascadia subduction zone to the North from transform tectonics of the San Andreas plate boundary. This actively deforming region experiences high seismic activity and young geological features. Here we examine offshore and onshore seismic wide-angle reflection and refraction data north of the MTJ crossing the Cascadia subduction zone from offshore northern California to the Western edge of the Sierra Nevada. We image subsurface structures in this region by creating P-wave velocity models using datasets collected in 1993 to 1994 …

A Combined Field, Experimental And Modeling Approach To Understand The Impacts Of Flood Irrigation On Pedogenic Caco3 And Co2 Dynamics In Drylands, Anna Cristina Ortiz

Open Access Theses & Dissertations

Soil salinization is a global problem affecting 10% of agricultural soils, particularly in irrigated arid-lands. This study investigated salt loading through flood-irrigation, particularly of calcite (CaCO3) salt in the southwest of the United States. To evaluate the impact that flood-irrigation has on CaCO3 buildup and its effect on C-cycling, a natural soil and two agricultural soils were sampled: a pecan orchard and an alfalfa field in the El Paso, TX region. Agricultural soils in this study are flood irrigated by the Rio Grande river and by ground waters in its absence, both of which are oversaturated with calcite.

To trace …

Geometry, Timing, And Kinematics Of Neogene Extensional And Transtensional Structures Of Southern Death Valley: Implications For Regional Reconstructions And A Corrective Method For Rigid Body Rotations, Zachariah Fleming

Open Access Theses & Dissertations

Chapter 1:Advancements in computing capabilities over the last decade have allowed for the routine creation of Structure from Motion-Multiview Stereo (SfM-MVS) terrain models that can serve as base for high resolution geologic mapping. Outcrops models developed from these systems are high-resolution, photo-realistic 3D base providing unprecedented capability for geometric analysis. Yet, before this technology becomes a mainstay of field geology, the potential errors associated with it must be well understood. Here, we compare orientation measurements from multi-point analyses on the SfM-MVS point clouds to those taken in the field with the objective of resolving the geometry of complex folds within …

Comparison Of Mesoscopic Fracture Analysis Techniques: A Case Study Near Onion Creek Diapir, Paradox Basin, Utah, Muhammed Tarik Iraz

Open Access Theses & Dissertations

Faults and fractures are abundant along the diapir contact in the Onion Creek Diapir in eastern Utah and relate to the mechanisms of diapir formation. Western Onion Creek exhumes two spectacular exposures of the diapir contact and adjacent wall rocks providing two nearly orthogonal transects oriented ~E-W and S-N. In this study, I used field measurements from natural outcrops and a 3D model developed using Structure-from-Motion/Multiview Stereo photogrammetry to evaluate fracture reservoir development along diapir margins. The 3D-Model was developed using Agisoft Photoscan from ~3200 ground-based images and was georeferenced using 76 ground control points located with a GPS unit …

Facies Changes Associated With Formation Of An Extensive Salt Shoulder By The Coastal And Eolian Carmel And Entrada Formations, Gypsum Valley, Colorado, Ryan Burtron Ronson

Open Access Theses & Dissertations

A salt shoulder forms a zone at the margin of a salt diapir where that margin steps relatively abruptly inward. These shoulders form when the salt rise rate near the diapir margin substantially decreases or stops relative to the salt rise rate at the inboard central part of the diaper. Based on current models of interactions between these salt shoulders and overlying sediment, it was anticipated that the thickness changes of the Entrada and Carmel formations would be only gradual and that any notable thinning would take place proximal to the neck portion of the diapir that would still have …

Grenvillian Tectonomagmatic Evolution Of Southwestern Laurentia; Virtual Tour Of Multidimensional Orders Of Scale; Two Methods To Describe The Vastness Of Time; Math Concepts Utilizing Google Earth; Systematic Approach To Motion Analyses; Mathematics And Earth Science-Based Knowledge And Learning, Anthony M. Alvarez

Open Access Theses & Dissertations

This Dissertation is the product of several individual multi-disciplinary investigations that cover a variety of topics in mathematics, physics, geology, and geoscience education. The first chapter formulates a better understanding of the timings, magma source, and relationships between dikes and associated magmatic bodies of the Red Bluff Granitic Complex to provide a clearer picture of the evolution of post-Grenville magmatism and tectonism of southwestern USA. The second chapter provides an improved method for representing spatial information in the form of a multidimensional virtual tour where the background map is used as a central object. The third chapter describes two methods …

Effects Of Gradation And Moisture Content On Resistivity Of Mechanically Stabilized Earth Wall Backfill Materials, Jose Luis Arciniega

Open Access Theses & Dissertations

The service life of mechanically stabilized earth (MSE) walls depends on the corrosion rate of the metallic reinforcement used in their construction. The resistivity of the backfill aggregates needs to be measured accurately in order to estimate realistically the corrosion rate of the reinforcement. Resistivity testing is usually performed using the traditional soil box on the portion of the aggregates that passes a No. 10 or No. 8 sieve to either select or reject the backfill. For a more reasonable characterization of the corrosivity of coarse backfills, it is desirable to use their actual gradations. To that end, several resistivity …

Gravitational Analysis And Fault Identification Within An Active Rift Basin: The Mesilla Valley Bolson In Western Texas - Southern New Mexico, Jose Pablo Cervantes

Open Access Theses & Dissertations

The metropolitan region of El Paso Texas and Ciudad Juárez, Chihuahua, located within the northern Chihuahua Desert, contains approximately two million inhabitants. The two main aquifers that supply groundwater to this region are the Mesilla and Hueco Bolsons. Both bolsons have been tapped for decades without sustainable recharge. This study's purpose is to use geophysical methods coupled with published geochemical analyses to determine the structural and stratigraphic controls on the quality and quantity of groundwater in the southern Mesilla Bolson.

The Mesilla Bolson is one of many fault-controlled basins within the Rio Grande Rift - southern Basin and Range. Faults …

Trace Metal And Metalloid Behavior In The Submicron Scale Components Of Coal Fly Ashes: Insights From Combined Microscopic And Microbiological Studies, Matthew Costa

Open Access Theses & Dissertations

For over a century, coal has been used worldwide to meet ever-growing energy demands. Coal combustion accounts for over 30% of electricity generation in the United States. In the U.S., coal combustion produces annually over 100 million tons of coal combustion products (CCPs) of which only 30% are used in beneficial and economic ways. One of the primary CCPs from coal-burning power plants is fly ash, typically fine-sized and enriched in many trace elements (e.g., arsenic, chromium, lead, and vanadium). When disposed in the environment, fly ash may release significant concentrations of trace elements into surrounding ecosystems and induce toxicity …

Biologically Available Phosphorus In Biocrust-Dominated Soils Of The Chihuahuan Desert, Grace Margaret Crain

Open Access Theses & Dissertations

In desert soils, phosphorus (P) is an important limiting nutrient and its cycling characteristics are less understood compared to nitrogen and carbon. Phosphorus cycling is controlled by both geochemical and biological factors. Traditionally, P availability has been characterized via sequential extraction analyses such as Hedley fractionation, but newly developed extraction methods allow for the examination of more biologically relevant P fractions, providing insight on mechanisms of P acquisition by plants and microbes. We examined these P cycling features in the context of biological soil crusts (biocrusts), which have been found to be important drivers of nutrient cycling and have the …

Evaluating Fold And Thrust Systems Within An Inverted Basin: Indio Mounntains, West Texas, Myra Guerrero

Open Access Theses & Dissertations

Fold and thrust belts often are complicated by out of sequence thrust faulting and inverted basins display these structures particularly often due to reactivation of original normal faults as well as complex topographic evolution. The Indio Mountains lie along the northern margin of the Chihuahua trough which formed as a mid-Cretaceous extensional basin and was subsequently shortened during the Laramide orogeny, making the Indio Mountains an exceptional site for studies of structures produced by large scale basin inversion. This study focuses on the subsurface structures in a complexly imbricated thrust window developed along the paleo rift basin margin.

This study …

Attributes Of The Fisher Valley Megaflap And Comparison To The Gypsum Valley Megaflap, Paradox Basin, Utah And Colorado: Implications For Controls On Megaflap Formation, Kate Grisi

Open Access Theses & Dissertations

Megaflaps are panels of steeply dipping to overturned strata that extend kilometers up the side of a salt diapir or equivalent weld. They often form important components of salt-diapir related hydrocarbon systems, though little is known about their geologic characteristics or how they form. In this study, I collected structural, stratigraphic, and sedimentologic data of the Fisher Valley megaflap and compared these attributes to the previous studied Gypsum Valley megaflap to test the differential sediment loading model proposed for initiation of megaflap formation. This model predicts that the sediment source proximal megaflap of Fisher Valley should have started rotation earlier, …

Assessing The Hydrologic Impacts Of Extreme Rainfall And Land Use Change On A Semiarid Watershed, Tahneen Jahan Neelam

Open Access Theses & Dissertations

Abstract: Intense precipitation events increase the risk of flash floods in the New Mexico-Texas-Mexico border region. Compounding effects of changing land use and precipitation pattern can influence rainfall-runoff processes that govern flash flooding. Paradoxically, this southwestern semiarid watershed has substantial water conflict that may get worse by 2025 due to changing climate and increasingly competitive demands for over-appropriated water resources. Using Soil and Water Assessment Tool (SWAT), we investigate the impact of changes in precipitation intensity and land use on runoff and arroyo flows in the dry, mountainous terrains. The baseline watershed simulation model shows that for a statistically insignificant …

Investigating The 2016 Jackson, Wyoming Earthquake Sequence Using Waveform Cross-Correlation And Seismic Array Methods, Emily Jo Graves

Open Access Theses & Dissertations

During a visual inspection of PDAR data extracted for the catalog events, I observed additional, unreported events, which is to be expected during an energetic swarm or seismic sequence. The casual observation of missed events strongly implied that more such missed events could be found in the data, which could improve the completeness of the earthquake catalog for the Jackson, Wyoming area. Catalog completeness improves our assessment of a region's tectonic behavior and earthquake exposure. To search for recurring swarm or earthquake sequence behavior, I applied waveform correlation methods to scan nearly two decades of continuous PDAR waveforms, comparing to …