Earth Sciences Commons^™

Hindcasting The Occurrence Time Of Major Earthquakes Using Machine Learning And Time Series Analysis, Rubidha Devi D

Theses and Dissertations

An earthquake is an intense shaking of the ground that typically occurs when tectonic plates move beneath the surface of the Earth. Scientists analyze historical seismic records and geophysical and atmospheric signs to build models estimating the probability of major earthquakes by detecting patterns and anomalies in data such as ground deformation and seismic waves. This study would help in predicting earthquakes to minimize risks of people and buildings.

The present study investigates the devastating earthquakes along the Chilean subduction zone in South America, linking non-seismic data to machine learning predictions of Outgoing Longwave Radiation (OLR) and Relative Humidity (RH) …

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.

The Future Intensification Of Hydrological Extremes And Whiplashes In The Contiguous United States Increase Community Vulnerability, Surendra Maharjan, Wenzhao Li, John D. Bolten, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Hydroclimatic whiplash rapid shifts between drought and flood poses growing risks to U.S. communities. Here, we assess historical extremes and future projections using a normalized streamflow metric: the annual mean flow’s deviation from the 1981–2020 average, expressed as a fraction of that average. This metric is applied to United States Geological Survey records and Localized Constructed Analogs downscaled projections under Representative Concentration Pathways 4.5 and 8.5. Results reveal sharp regional disparities, with drought deficits exceeding 300% of normal flow during multi-year droughts. By linking hydrologic outcomes with the Federal Emergency Management Agency’s National Risk Index, we find that counties facing …

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, …

The Compositional And Dynamical Properties Of Exoplanets, Cody James Shakespeare

UNLV Theses, Dissertations, Professional Papers, and Capstones

The solid surface density profile of protoplanetary discs, and the composition of these solids, can be formed through sequential condensation models of dust precipitating from the cooling gas of the solar nebula. I continue developing a code that reproduces the chemical compositions of most chondrites as well as the bulk compositions of the rocky planets using our partial condensation model with an evolving disc. I extend this validated code to exoplanet systems with different initial elemental ratios, like the carbon-to-oxygen ratio and estimated stellar abundances over the age of the universe. I have improved this dust condensation code to include …

Postglacial Erosional Response Of A Permafrost Landscape Across Decadal To Millenial Timescales, Aklavik Range, Arctic Canada, Bailey J. Nordin

Dartmouth College Master’s Theses

Rapid warming and permafrost thaw across Arctic landscapes are projected to drastically accelerate local erosion rates and sediment fluxes to downstream systems and the communities that rely on them. However, interpreting this signal of change first requires disentangling the relative contributions of postglacial landscape responses, periglacial processes, and modern warming to observed changes in erosion. To explore this problem, we combine a suite of geochronometers to examine erosion and deposition rates over timescales of 10²–10⁷ years across a periglacial alluvial fan and catchment system on the former margin of the Laurentide Ice Sheet in the Aklavik Range …

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 …

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 …

Awaiting The Colorado River 24-Month Study, John Fleck, Anne Castle, Eric Kuhn, Jack Schmidt, Kathryn Sorensen, Katherine Tara

The Traveling Wilburys of the Colorado River

No abstract provided.

From Coastal Retreat To Seaward Growth: Emergent Behaviors From Paired Community Beach Nourishment Choices, Jorge Lorenzo-Trueba, Arye Janoff, Oshane Thomas, Di Jin, Porter Hoagland, Andrew Ashton

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Coastal communities often address shoreline erosion through beach nourishment, adding externally sourced sand to widen beaches for recreation and property protection. While nourishment enhances beachfront property values, the need for periodic maintenance creates interdependencies where the actions of neighboring communities affect local shoreline dynamics. Using a coupled model of two neighboring communities, we examine the interplay between community nourishment decisions and the redistribution of nourishment sand. We find that the value a community places on wider beaches not only influences their propensity to nourish, but also their and their neighbors' nourishment efficiency and net benefits. Communities that nourish more frequently …

Enhancing Sustainable Rice Production Through Organic Plus Fertilizer In Irrigated Paddy Fields, Oviyanti Mulyani, Emma Trinurani Sofyan, Ania Citraresmini, Benny Joy, Anne Yuliana Husen

Jurnal Kultivasi

Sustainable rice farming is increasingly threatened by declining soil fertility, excessive reliance on chemical fertilizers, and environmental degradation from intensive agricultural practices. There is an urgent need for innovative organic fertilizer products that combine organic materials with macro and micronutrient enhancements to restore soil health effectively. This research aimed to evaluate the effect of organic plus fertilizer (OPF) as a sustainable soil amendment to improve soil nutrient status, increase paddy productivity, and enhance overall soil health. The experiment was conducted using a Randomized Block Design (RBD) with nine treatments: one recommended OPF dose, six combinations of NPK (75 – 100%) …

Effect Of Eco-Enzyme Application On Soil Nutrient And Plant Productivity Of Green Mustard-Peanut In Inceptisol, Idris Abd Rachman, Buhari Umasugi, Krishna Aji, Nurul Fahira A Hakim, Adnan Sofyan, Asrul Dedy Ali Hasan

Jurnal Kultivasi

Appropriate land management has a long-term impact on soil performance and is believed to improve soil fertility. This study investigated the effect of eco-enzymes on soil nutrients and plant productivity of green mustard-peanut in inceptisol. The research was conducted from February to April 2025. The experiment used a randomized block design (RBD) consisting of 5 treatments and replicated 3 times, so that there were 15 units, including N0 = without Eco-enzyme, N1 = Eco-enzyme 2cc/L. N2= Eco-enzyme 4cc/L, N3= Eco-enzyme 6cc/L, and N4= Eco-enzyme 8cc/L. The commodities used were green mustard (Brassica juncea L) and peanut (Arachis hypogaea Linn). Soil …

Ocean And Coastal Acidification Monitoring Priorities For The Northeast Us And Eastern Canada, Christopher Hunt, Austin Pugh, Jake Kritzer, Samantha Siedlecki, Kumiko Azetsu-Scott, Parker Gassett, Diane Lavoie, Adam Pimenta, Amy Trice, Elizabeth Turner

Faculty Publications

The Interagency Working Group on Ocean Acidification Monitoring Prioritization Plan 2024 calls for Coastal Acidification Networks to identify the ocean and coastal acidification (OCA) monitoring needs most important for their regions. The Northeast Coastal Acidification Network (NECAN) organized a webinar series to study regional needs, which culminated with a workshop in November 2023. This workshop led to the identification of six priority new Monitoring Needs in addition to the maintenance of current monitoring efforts:

• Improve spatial and temporal scale of monitoring co-located OCA variables and biological measurements to better resolve variability of acidification dynamics in concert with biological processes …

From Anorthosite To Silicic Volcanics: Photometry, Composition, And Buoyancy Of Crustal Rock Types On The Moon, Emily Margaret Culley

Arts & Sciences Graduate Student Theses and Dissertations

To better constrain the formation and evolution of the lunar crust, this dissertation addresses two key aspects of lunar crustal formation: the primary feldspathic crust, formed during solidification of an ancient lunar magma ocean (LMO), and non-mare silicic volcanic constructs, which represent either secondary or tertiary crustal formation processes. Specifically, we performed photometry on Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) images to determine the single-scattering albedo (SSA) of surface features that expose these two non-mare crustal rock types. Using digital terrain models (DTMs) derived from LROC NAC images of each analysis region, we accounted for potential topographic …

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 …

Performance Mapping And Weighting For The Evapotranspiration Models Of The Openet Ensemble, M. Reitz, J. M. Volk, T. Ott, M. Anderson, G. B. Senay, F. Melton, A. Kilic, R. Allen, Joshua B. Fisher, A. Ruhoff, A. J. Purdy, J. Huntington

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Evapotranspiration (ET) accounts for the majority of water available from precipitation in the terrestrial water cycle, and improvements to the accuracy, resolution, and coverage of ET data can enhance hydrologic models and assessments. The OpenET collaboration of six remotely sensed ET modeling teams has demonstrated that an ensemble approach to ET estimation generally provides improved accuracy relative to individual ensemble members. The performance of individual models has been shown to vary by land cover type and climate zone, but a thorough study of the variables that influence model performance differences has not yet been conducted. In this paper, we model …

Growth And Yield Of Curly Red Chili (Capsicum Annum L.) In Response To Mulching And Chicken Manure Application In The Erosion-Prone Area Of Loto, Ternate Island, Tri Mulya Hartati, Lily Ishak, Krishna Aji, Chumidach Roini

Jurnal Kultivasi

Information on soil resources in volcanic landscapes presents a high potential for agricultural land development, but its development is always faced with the potential for continuous land degradation. This study aims to reduce the rate of land degradation through the application of vegetative conservation in erosion-prone Loto agrotourism area, Ternate Island. The research location is focused on erosion-prone areas. The research consisted of a soil resource inventory and a vegetative conservation application. The vegetative conservation application method used a Randomized Block Design (RBD) pattern, composed of 2 factors. The first factor is mulching, namely: no mulching (M0) and mulching (M1), …

Assessing Greenhouse Gas Emissions From Michigan’S Drowned River Mouths Using In Situ And Remote Sensing Methods, Jillian A. Greene

Masters Theses

Freshwater estuaries are natural contributors to the carbon cycle including production and emission of methane (CH4) and carbon dioxide (CO2), potent greenhouse gases (GHGs); however, estimates of their contribution to regional and global GHG emissions is largely unconstrained. Few studies have examined the quantification and drivers of lake CH4 and CO2 production in the Great Lakes region and how it may differ in response to anthropogenic development. In this study, CH4 and CO2 emissions were measured from three drowned river mouth estuaries (DRMs) along the eastern shore of Lake Michigan in 2024. The DRMs exist along a latitudinal gradient ranging …

Post-Drought Growth Recovery Of Tea (Camellia Sinensis) Under Different Techniques And Doses Of Biofertilizer Applications, Nabila Ragil Wiharti, Intan Ratna Dewi Anjarsari, Yudithia Maxiselly

Jurnal Kultivasi

Drought stress is a major limiting factor affecting the growth, yield, and quality of tea (Camellia sinensis). The present study aimed to analyze the success of post-drought growth recovery of tea in response to different techniques and doses of biofertilizer applications. Field experiments were conducted from January to August 2024 in the experimental garden of the Research Institute for Tea and Cinchona, Gambung Blok A8, Bandung. This work was arranged in a split-plot design, consisting of a main plot with two biofertilizer application techniques (foliar feeding and soil drenching) and subplots with four levels of biofertilizer dosage (control (B1), 15 …

Efficacy Of Lactobacillus Rhamnosus And Its Metabolites To Mitigate The Risk Of Foodborne Pathogens In Hydroponic Nutrient Solution, Esther Oginni, Robin A. Choudhury, Veerachandra Yemmireddy

School of Earth, Environmental, & Marine Sciences Faculty Publications

Hydroponic nutrient solution (HNS) has been established as an ideal conduit for pathogen contamination and proliferation. This study evaluated the efficacy of lactic acid bacteria and their metabolites in mitigating the risk of foodborne pathogens in HNS when compared to conventional chemical treatments. Hoagland’s HNS were prepared according to the manufacturer’s instructions and inoculated with Salmonella Typhimurium, Escherichia coli 0157:H7, and Listeria innocua at 105 CFU/mL cell concentration. These nutrient solutions were subjected to treatment with various concentrations of Lactobacillus rhamnosus live cells, a cell-free extract (CFE) of L. rhamnosus metabolites, sodium hypochlorite and peroxyacetic acid at 22 ± 1 …

Soil Ethics In Practice: Harvesting Conservation Choices Among Puerto Rican Coffee Farmers, Patricia Marie Cordero-Irizarry

Theses and Dissertations

Coffee farming in Puerto Rico has declined over recent decades, partly due to deteriorating soil quality. However, the decision-making process behind farmers’ adoption of soil conservation practices remains unclear, particularly the overlooked role of soil ethics, which emphasizes the moral principles guiding human relationships with the soil. This mixed-methods study examined coffee farmers’ adoption of soil conservation practices by integrating the Values-Beliefs-Norms (VBN) theory and a newly developed Soil Ethics Survey (SES) instrument for the quantitative component, while using Decision-Making Theory and Social Cognitive Theory to qualitatively explore how farmers’ experiences and reflections shape their soil ethics. Quantitative findings revealed …

Activation Or Deactivation? Rethinking Ferrate(Vi) Reactivity Within A Broader Modulation Framework, Zepei Tang, Yang Deng

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

No abstract provided.

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 …

Groundwater-Dependent Ecosystems In Southeastern Utah: An Integrated Analysis Of Hydrology, Ecology, And Landscape Change, Colten Lay

All Graduate Reports and Creative Projects, Fall 2023 to Present

In Southeastern Utah, springs play a critical role in sustaining groundwater-dependent ecosystems (GDEs) in a semi-arid environment. However, they remain understudied and face growing threats from climate change, land use modifications, and hydrologic alterations. This study addresses knowledge gaps in spring occurrence, hydrologic function, and ecological condition by integrating field surveys, remote sensing, and geospatial analysis across multiple spatial scales. It provides a comprehensive assessment of spring hydrology, water quality, and ecological conditions using field surveys, remote sensing, and GIS analysis to establish a foundational baseline of GDE resources in the region. I applied a multi-scale monitoring approach across the …

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 …

Mapping Sedimentary And Crustal Thicknesses In The Northern Atlantic Ocean From Public Domain Geophysical Data, Hermione Lofton

College of Arts and Sciences: Undergraduate Theses and Other Student Projects

The Northern Atlantic Ocean is a complex region that contains many inactive and active tectonic features. These features include the Jan Mayen Microcontinent, Jan Mayen Fracture Zone, Aegir Ridge, Kolbeinsey Ridge, the Greenland-Iceland-Faroe Ridge, the Voring Plateau, the Voring Spur, and the Iceland Hotspot. This project is motivated by the region’s complex geology and its highly debated tectonic history and disputed crustal affinity. This study aims to evaluate tectonic elements of the Northern Atlantic Ocean with three major objectives. The first objective is to develop a map of crustal thickness from publicly available seismic refraction data. For the second objective, …