Geology Commons^™

Paleoseismic Evidence Of Directivity For The 1976 Mw 7.5 Motagua Earthquake, Guatemala, Jonathan Obrist-Farner, Jeremy Maurer, Derek Gibson, Trenton Mcenaney, Andreas Eckert, William F. Kenney, Jeffrey Beeson, Nigel Wattrus, Quin Stangeland, Fatima Reyes

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

On 4 February 1976, a Mw 7.5 earthquake along the Motagua fault, Guatemala, ruptured ∼230 km of the North American and Caribbean plate boundary. Today, the plate boundary remains poorly monitored, and the 1976 earthquake is still not fully understood. Here, we present seismic reflection profiles and radiometrically dated sediment core data from six lakes around the Motagua fault, together with reports of destruction and a quasi-dynamic rupture model, which show that the 1976 earthquake experienced strong directivity that impacted the distribution of shaking. The earthquake left behind a detailed record of event deposits (EDs) in five of the six …

Compound-Specific Isotope Records Of Dust Provenance And Hydroclimate In The North Pacific And Marginal Seas Of East Asia: Integrating N-Alkane Δ13c And Δd With Standardized Analytical Frameworks, Julian W. Traphagan

LSU Doctoral Dissertations

This dissertation presents advancements in compound-specific isotope analysis (CSIA) through methodological innovation and paleoclimate reconstruction in Central and East Asia. Utilizing plant wax n-alkanes from International Ocean Discovery Program (IODP) and Ocean Drilling Program (ODP) sediment cores, this research reconstructs atmospheric circulation shifts responding to tectonic evolution and climate transitions since the Late Miocene.

Chapter 1 investigates hydrogen isotope compositions (δD_wax) from IODP U1430 (Sea of Japan), ODP 886, and ODP 1208 (North Pacific) to trace dust provenance and hydroclimate changes since ~13 Ma. Results reveal persistently segmented source-to-sink systems: the Sea of Japan dominated by westerly …

Geol 64: Planetary Geology - Syllabus, Dara Laczniak

Open Educational Resources

This Open Educational Resources (OER) syllabus is for an introductory planetary geology course that utilizes results from space missions to expose students to the surface features, composition, geological activity, and probable history of the planets, moons, asteroids, and comets of the solar system. It also places space exploration into the context of larger societal issues such as global warming and natural resource availability and addresses topics such as the ethics of space exploration and hazards of space travel. This OER syllabus aims to foster student-centered learning, critical thinking, data analysis and communication skills, and creativity. Assigned readings are compiled into …

Mantle Flow And Fault Zone Related Seismic Anisotropy Revealed By A Dense Linear Broadband Array In Southeast Tibet, Jing Wu, Yinshuang Ai, Stephen S. Gao, Peixi Huang, Fansheng Kong, Deke Xu, Jianguo Song, Xinyu Gao, Mengyi Wei, Long Li, Jien Zhang, Yanbin Zhang, Yingying Zhang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Southeast Tibet, a key region for the southeastward extrusion of the Tibetan Plateau, remains debated in terms of its tectonic deformation in response to the ongoing collision between the Indian and Eurasian plates. In this study, we applied shear-wave splitting analysis of core-refracted phases recorded by a newly deployed dense seismic array and six permanent stations to delineate crustal and mantle deformation processes. The observed fast polarization directions are predominantly aligned NNW–SSE, while the splitting delay times vary across four sub-blocks. The anisotropy pattern suggests a dominantly asthenospheric origin, consistent with southeastward-directed mantle flow associated with the extrusion of the …

The Hydro-Geomorphic Response Of The Ephemeral Lower Nahal Tzalmon Stream To Experimental Flow Releases Towards Replenishment Of The Sea Of Galilee, Ne Israel, Nathaniel Bergman, Noam Greenbaum, Eyal Weinberg, Iyad Swaed

Geology Faculty Publications and Presentations

Study region:

The Sea of Galilee’s western watershed includes the Lower and Upper Galilee subregions in northern Israel. Nahal Tzalmon stream (110 km2) is one of the major gravel-bed channels draining those subregions into the lake. Study focus: The study focus was to monitor the immediate effects of introducing “hungry water” from the newly mega-project of the “Reverse National Water Carrier” (RNWC). The project was designed to convey desalinated water from the Mediterranean coastal desalination plants through a 5 km open channel into the lower Nahal Tzalmon stream in order to replenish the Sea of Galilee. During a 2-day experimental …

Geochemical And Thermobarometric Constraints On Granite Crystallization, Glenn Tristan Thompson

Dissertations - ALL

Granite is ubiquitously recognized by many people due to its common use as a building material and its abundance in the Earth's continental crust. From countertops to library steps, and as a source of economically important elements, granitic rocks are deeply intertwined with human development. Defining the pressure and temperature (P– T) conditions under which granitic composition magmas crystallize is critical for understanding their petrogenesis. This dissertation explores granite petrogenesis across three chapters, utilizing detailed analysis of rock-forming minerals, associated fluids, and geochemical variations to understand how compositional variability influences the lowest possible crystallization conditions. Chapter 1 investigates the physical …

Dissolution Mechanism Of Nonionic Polyether Surfactants In Supercritical Co2, Ning Xu, Yanling Wang, Baojun Bai, Shizhang Cui, Zan Gao, Yu Zhang, Di Li, Wenjing Shi, Wenhui Ding, Peixu Ma

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Polyoxyethylene ether is an efficient CO₂-philic compound with significant potential applications in CO₂ flooding, which requires CO₂-philic surfactants with high solubility in supercritical CO₂ (scCO₂). This study elucidates the molecular and atomic-level dissolution mechanism of the fatty alcohol polyoxyethylene ether (AEO) in scCO₂ by combining phase-behavior experiments and molecular dynamics simulations. The solubility of AEO in scCO₂ is measured using a semiconductor laser. AEO containing three polyoxyethylene (EO) groups exhibited the highest solubility in scCO₂.The solubility of AEO in scCO₂ decreased with an increase in the number …

Geol 12 Natural Disasters Syllabus, Anestoria Shalkowski

Open Educational Resources

Hazards are events which have the capabilities to damage property and or life. Understanding natural hazards and how these can become disasters are important in reducing the impacts of such events. This syllabus provides a description of the material to be examined and the expected student outcomes upon completion of the course.

Receiver Function Imaging Of The Mantle Transition Zone Beneath The East Sayan Mountains And Adjacent Area In Central Asia: Implications For Lithospheric Drip And Intraplate Cenozoic Volcanism, Yangyang Liao, Kelly H. Liu, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

To provide constraints on the formation mechanisms of intracontinental volcanisms and intriguing lithospheric thickness variations in the East Sayan Mountains and surrounding areas, we stack P-to-s receiver functions to image the 410-km and 660-km discontinuities. Mantle transition zone (MTZ) thickening observed in a continuous area is attributable to ancient slab remnants, and Cenozoic volcanisms in the peripheral area can be explained by slab dehydration. The thinning of the MTZ in the Tuva-Mongolian Massif can be explained by mantle upwelling branches induced by slab subduction. Our results reveal an approximately circular area in the MTZ that is significantly thicker than usual, …

Multi-Sensor Remote Sensing Captures Geometry And Slow-To-Fast Sliding Transition Of The 2017 Mud Creek Landslide, Alexander L. Handwerger, Pascal Lacroix, Andrew F. Bell, Adam M. Booth, Mong-Han Huang, Simon M. Mudd, Roland Bürgmann, Eric J. Fielding

Geology Faculty Publications and Presentations

Landslides pose a significant hazard worldwide. Despite advances in landslide monitoring, predicting their size, timing, and location remains a major challenge. We revisit the 2017 Mud Creek landslide in California using radar interferometry, pixel tracking, and elevation change measurements from satellite and airborne radar, lidar, and optical data. Our analysis shows that pixel tracking of optical imagery captured the transition from slow motion to runaway acceleration starting ~ 1 month before catastrophic failure—an acceleration undetected by satellite InSAR alone. Strain rate maps revealed a new slip surface formed within the landslide body during acceleration, likely a key weakening mechanism. Failure …

Understanding Ore Deposit Scale Controls On Au Enrichment In Carlin-Type Au Mineralization: A High-Resolution Study Of The Rita K Deposit, Conner T. Callaway

UNLV Theses, Dissertations, Professional Papers, and Capstones

Controls on the distribution of gold (Au) within the Rita K Carlin-type deposit are poorly understood. The primary Au-bearing carbonate unit Wispy, is a bioturbated muddy limestone with debris flow clasts that range in size but are typically >5 cm occurring in the lower sections. The orebody is described as a syncline-anticline pair that hosts high-grade Au ore in the fold hinges. The spatial relationship between Au mineralization and fold hinges suggests that shortening due to folding is an important mechanism producing Au-enriched zones. However, the exact mechanism of Au enrichment and deposit-scale controls on Au distribution and fluid evolution …

Mechanisms Of Gold Enrichment In Seafloor Massive Sulfide Deposits: A Study On The Higashi-Aogashima Hydrothermal Field, Claudia Martinez

UNLV Theses, Dissertations, Professional Papers, and Capstones

The study of Seafloor Massive Sulfides (SMS) deposit formation is vital for assessing both the economic potential and environmental risks posed by future marine mining projects. Metal-rich SMS deposits form in hydrothermal vent systems within tectonically active regions, such as back-arc basins, where faults enhance crustal permeability, enabling fluid migration driven by magmatic heat sources at depth in the crust. Currently our understanding of SMS formation processes is based on bulk-rock geochemical and isotopic data, lacking the necessary spatial and temporal resolution to understand ore forming processes. As a result, critical gaps remain in understanding the exact mechanisms responsible for …

Quantifying Erosion Rates Of The Mission Hills Along The Calaveras, Mission, And Hayward Faults In Northern California To Better Understand The Role Of Fault Geometry On Surface Topography, Ian Duncan Lord

Master's Theses

The San Francisco Bay Area lacks publications on erosion rates and their relationship to restraining bend fault geometry. This thesis presents a detailed geochronologic study of erosion rates from the Mission Hills along the Calaveras, Mission, and Hayward faults located northeast of San Jose, California. The goals are to provide erosion rate values where none currently exist and to gain a better understanding of how fault geometry influences topography along restraining bends. To quantify the erosion rate of these faults, river sediments containing 10Be were collected from 14 catchments using well-established protocols. Of the successfully processed samples, the erosion rates …

A Groundwater Flow System Investigation In The Upper Rowena Creek Drainage, Oregon, Catelee Yamei Kambur

Dissertations and Theses

Groundwater level declines are a growing concern within the upper Rowena Creek drainage, Oregon. This area is home to a small community located on the upper limb of the Columbia Hills anticline, where local residents rely on aquifers within the Columbia River Basalt Group (CRBG) for domestic water supplies. Groundwater level declines in CRBG aquifers have been studied more extensively in the Mosier area, which lies approximately 5 miles to the northwest of Rowena, but there has been little research conducted specifically on the upper Rowena Creek drainage area. Rowena is located higher up the dip of the Columbia Hills …

Dream Pilot Project: Analysis Of Groundwater Development At Six Villages In Ethiopia, Lindsay K. Gordon

All Graduate Reports and Creative Projects, Fall 2023 to Present

This study presents a hydrogeologic assessment of the Distributed Renewable Energy Agriculture Modalities (DREAM) pilot project, an ongoing groundwater development initiative in rural Ethiopia. This project integrates solar-powered groundwater infrastructure across six villages to improve water access, agricultural productivity, and economic stability.

Fourteen production wells were installed at Murche, four at Dalle, and additional test wells at Murche, Dalle, Chefe Kora, and Huluku. Transmissivity values and the number of wells at Murche suggest that local water needs are currently being met. In contrast, fewer wells were drilled at Dalle. This reflects the high cost of well construction relative to yield, …

Evaluating Uplift At The Leading Edge Of The Yellowstone Hotspot - A Study Of The Shoshone River Drainage, Emma Tombaugh

All Graduate Theses and Dissertations, Fall 2023 to Present

The stationary mantle plume (or hotspot) underlying the Yellowstone region has caused parts of the surrounding landscape to rise as the continental plate migrates over it. However, scientists do not fully agree on the spatial pattern of this uplift and few measurements of the landscape have been made to provide estimates of uplift rates. To better understand uplift patterns and rates, this study examines the Shoshone River, which flows across the predicted zone of highest uplift at the northeastern, leading edge of the hotspot. Digital-terrain analysis is used to measure channel steepness and field and imagery approaches are used to …

Geochemical And Stratigraphic Characterization Of The Morrison Formation And Cedar Mountain Formation Contact In The Island Park Quadrangle, Uintah County, Utah, Emily Mcdermott

All Graduate Theses and Dissertations, Fall 2023 to Present

The Upper Jurassic Morrison Formation and Lower Cretaceous Cedar Mountain Formation are among the richest sources of dinosaur fossils. Despite a 24-million-year gap in time (the Jurassic–Cretaceous unconformity), these formations are difficult to distinguish due to their similar rock types and colors. In Utah's Island Park quadrangle (IPQ), these formations are not separated on existing geological maps. This study focuses on identifying and understanding the formational boundary between them using field observations, stable isotope analysis, clay mineralogy, and chemical techniques such as X-ray diffraction (XRD) and X-ray fluorescence (XRF).

Unlike other areas where a conglomerate layer marks the boundary, the …

Role Of Quartz Grain Size And Saturation On Fault Strength And Frictional Healing, Sapana Regmi

All Graduate Theses and Dissertations, Fall 2023 to Present

Rocks near the Earth's surface (less than 5 kilometers deep) often break and grind against one another to create crushed rock materials known as fault gouge. These fault gouges are filled with fragmented particles and broken rocks, which vary in grain size over time and space due to repeated earthquakes. This variation in grain size distribution along fault gouge can affect the strength of the fault, how it slips during an earthquake and how it 'heals' or recovers strength between earthquakes. Further, fault gouges often contain water from underground sources, which can influence how they slip. Previous studies have examined …

High-Resolution Event Stratigraphy Of Ostracods In The Ozan Formation Of Texas And Arkansas, Denali L. John

Master's Theses

This study focuses on the high-resolution event stratigraphic framework of the lower Campanian Ozan Formation in Northeast (NE) Texas and Southwest AR which is richly fossiliferous in ostracods. Little research has been published on the Ozan Formation and even less dealing with Ozan ostracods. Additionally, correlation of Upper Cretaceous units between Texas and AR is controversial due to the general lack of good exposures in both regions and extensive faulting in Northeast Texas despite similar depositional environment across the region. This study calibrates the ranges of ostracods and creates an event stratigraphic composite that is orders of magnitude higher in …

Using Geomorphic Change And Sediment Modeling To Calculate Debris Flow Volumes From The 2020 El Dorado Wildfire In The Southern San Bernardino Mountains, California, Sevag Injean

Electronic Theses, Projects, and Dissertations

Four years after the occurrence of the 2020 El Dorado Fire, Yucaipa Ridge and the surrounding communities of Oak Glen and Forest Falls still experience the devastation caused by debris flows. Wildfires can instigate a series of events leading to hydrophobic soils, loss of vegetation, and increased sediment availability which amplify post-fire debris flow risks. This study tested the hypothesis that post-wildfire geomorphic changes can be accurately quantified and predicted using high-resolution LiDAR-derived digital elevation models. To investigate this hypothesis, multi-temporal LiDAR datasets were analyzed to quantify geomorphic changes, including erosion and deposition, within two severely burned basins in the …