Geology Commons^™

Downstream Gradients In Unit Stream Power Influence Log Jam Location And Process Domain, Eliza H. Malakoff

Dartmouth College Master’s Theses

Growing calls for the use of natural materials and processes to meet management goals have positioned artificial log jams as a compelling alternative to hard engineering instream and floodplain habitat. Deep uncertainties remain, however, about where and how wood should be placed to best mimic natural river processes. In this study, I test whether at-a-point or downstream gradients in unit stream power, an estimate of a river’s ability to do work, exert control over where and how log jams form. Using field observations of 360 log jams in New Hampshire and Vermont and an additional 320 previously published locations of …

Bulk Hydrogen Isotopes In Ordinary Chondrites, Michael J. Cato

Earth and Planetary Sciences ETDs

Bulk hydrogen isotopes in nominally anhydrous meteorites are a key component in our understanding of the distribution of hydrogen in our solar system, including the provenance of water on the Earth. Here, we develop a step-heated continuous-flow method to measure the bulk hydrogen isotopes in nominally anhydrous rocks and use this method to significantly increase the dataset of bulk hydrogen isotopes in ordinary chondrites, nearly doubling the number of equilibrated members. We found that as thermal alteration increases from petrologic type 3.0 to 4, there is a correlated decrease in both hydrogen content and isotope ratio, followed by no significant …

Evaluating The Relationship Between Methane Seeps And Seafloor Geomorphology On The Northern Us Atlantic Margin, Gabriel Hernandez

Theses and Dissertations

Methane seeps are a transport pathway for carbon from seafloor sediments to the marine environment with important implications for global biogeochemical cycling. Accordingly, there is substantial interest in better understanding the processes that control seep location and predicting the distribution of seeps with existing seafloor datasets. Visual evaluation of methane seeps, in multibeam sonar water column data, suggests a spatial relationship between seeps and specific seafloor morphologic features such as ridge crests. In this thesis, seafloor geomorphology at 1996 seep detection sites on the US Atlantic margin was quantitatively characterized by geomorphologic phonotype, bathymetric position index, slope, rugosity, and aspect …

Limits Of Tectonic Reactivation On Mars Using Earth Analogue Analysis And Numerical Modeling, Jonathan Rich

Theses and Dissertations

Recent geodynamic modeling studies suggest that the geometry of structural landforms in the Ouachita Mountains (OM) has been influenced by the reactivation of a weak scar in the mantle-lithosphere during intracontinental orogenesis. As deformation on one-plate planets such as Mars can be considered intracontinental, and impact cratering deeply scarred the Martian lithosphere, we hypothesize that structural geometries on Mars may also reflect heterogenous networks of lithospheric scarring. To investigate this hypothesis, we model the pre-erosional fold structure of the Maumelle Chaotic Zone in the OM to compare fault and fold geometries with that of the seismically-imaged mantle-lithosphere scar. We then …

Impact Of Lithological Variation And Topology On The Connectivity And Intensity Of Fracture Networks In Carbonates, Fahad Qassim

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Assessing fracture network connectivity in reservoirs remains a challenging task because of the complex nature of fracture networks at various length scales, which significantly impacts fluid flow behavior. Outcrop studies are essential for understanding subsurface fracture networks because intersecting fracture sheets' length, orientation, height distribution, and, therefore, network connectivity and intensity are difficult to measure from wellbores and are typically below seismic resolution. Nevertheless, fracture network connectivity is a crucial parameter and a critical factor in understanding, evaluating, and predicting fluid flow behavior in hydrocarbon reservoirs, aquifers, hazardous waste and CO₂ storage systems, and geothermal energy exploitation. Moreover, fracture …

Evaluating Snow And Ice Cover In Tierra Del Fuego, Argentina, Zoe Pitman

Geosciences Undergraduate Honors Theses

Evaluating changes in snow and ice cover is an important field for studying climate change and its impacts. This evaluation is commonly done using remote sensing because of its ability to evaluate large areas. The purpose of this study is to determine the reliability of one remote sensing technology, the Moderate Resolution Imaging Spectroradiometer (MODIS), by comparing it to in-situ snow and climate data from the weather station at the Austral Center for Scientific Research (CADIC). Data was converted from daily to monthly averages and was sorted into a series of graphs to compare the two data sets. Correlations were …

Fault Influence On Castle Mesa Fracture Node Pattern, Kaitlin Steinauer

Theses/Capstones/Creative Projects

Fracture nodes are useful in determining the connectivity of a fracture pattern which is important when considering hydrogeological and mechanical behavior of a rock. Four node types are used to describe the pattern, including isolated (I), perpendicular abutting (T), low-angle abutting (Y), and cross-cutting (X). Faults can affect a fracture pattern by creating a highly fractured zone in their vicinity. I investigate the Moab Tongue Member of the Entrada Formation at Castle Mesa in Moab, Utah to determine a) how the percentage of different node types changes with distance from the fault, b) any difference in node type proportions between …

Urban & Deltaic Subsidence In Bangladesh From Sentinel-1 Insar Data Analysis, Gavin Middleton

Masters Theses & Specialist Projects

Bangladesh's Bengal Delta faces multiple challenges, such as rising sea levels, coastal flooding, and high population density, leading to land subsidence, saltwater intrusion, and biodiversity loss. The region's groundwater security, essential for the country's survival, is at risk due to climate change and saltwater intrusion. Groundwater security is dependent on the Bengal Water Machine (BWM), which is at risk due to saltwater intrusion and monsoon rainfall distribution from climate change. Groundwater exhaustion leads to natural hazards such as subsidence, landslides, and flooding. A large portion of the population is at risk from groundwater insecurity, which requires mitigating worldwide greenhouse gas …

Dual Crosslinked Poly(Acrylamide-Co-N-Vinylpyrrolidone) Microspheres With Re-Crosslinking Ability For Fossil Energy Recovery, Jingyang Pu, Baojun Bai, Jiaming Geng, Na Zhang, Thomas Schuman

Chemical and Biochemical Engineering Faculty Research & Creative Works

Microspheres have been proposed to be applied in controlling wastewater production for mature oilfields and migrating leakage for gas and nuclear waste storage. However, it remains challenging for stacked microspheres to maintain strong blocking ability in micron-sized small pores or fractures. in this study, a novel microsphere was developed with comprehensive properties including high deformability and long re-crosslinking time upon tunable swelling ratio for the applications. a dual covalent and physical crosslinking strategy was used to develop novel microspheres reinforced by a hydrogen bond (H-bond, between pyrrole ring and amide group) and coordination bond (between chromium acetate (CrAc) and carboxyl …

Incorporating Community Science In Improving Environmental Data Quality Through Model Based Reasoning Techniques, John Gilbert Olgin

Open Access Theses & Dissertations

This dissertation will address the questions: In what ways can MBR theory be applied to designtraining that will improve the capacity of Citizen scientists to collect and analyze high quality scientific data? To what degree does this training impact their ability to formulate complex understandings of environmental problems in their Citizen? The project will be comprised of three research objectives focused in three sections, carried out with NASAâ??s GLOBE Observer Citizen Science Program:

Section 1: An analysis of existing GLOBE data will be conducted, identifying whereerrors in data collection originate. At least three principal errors will be selected from this …

Enhancing Basic Geology Skills With Artificial Intelligence: An Exploration Of Automated Reasoning In Field Geology, Perry Ivan Quinto Houser

Open Access Theses & Dissertations

This thesis explores the use of Artificial Intelligence, specifically semantics, ontologies, and reasoner techniques, to improve field geology mapping. The thesis focuses on two use cases: 1) identifying a geologic formation based on observed characteristics; and 2) predicting the geologic formation that might be expected next based upon known stratigraphic sequence. The results show that the ontology was able to correctly identify the geologic formation for the majority of rock descriptions, with higher search results for descriptions that provided more detail. Similarly, the units expected next were correctly given and if incorrect, would provide a flag to the field geologist …

Spot1328 Meira Spit, Robert C. Mahon, Elizabeth J. Trower, Benjamin P. Smith, Tyler A. Lincoln, Juliana Olsen-Valdez, John S. Magyar, Cedric J. Hagen

2D Wave Spectral Data, South Arm, Great Salt Lake, Utah

Data in this folder are produced by a SoFarOcean Spotter wave buoy deployed along the south arm of the Great Salt Lake, near Antelope Island State Park from the period of July 13, 2021 through June 28, 2022, in relatively shallow water, approximately 1.6m.

IMPORTANT NOTE: Water depths for #1328 (Miera Spit) started at ~1.7 m, but dropped rapidly to 0.9 m on July 15, 2021 and dropped further to ~0.4 m on August 17, 2021. The timing of these rapid water depth changes matches the timing of buoy location changes when the anchor was dragged inshore by waves. When …

Spot1328 Meira Spit Derived Data, Robert C. Mahon, Elizabeth J. Trower, Benjamin P. Smith, Tyler A. Lincoln, Juliana Olsen-Valdez, John S. Magyar, Cedric J. Hagen

2D Wave Spectral Data, South Arm, Great Salt Lake, Utah

Data in this folder are produced by a SoFarOcean Spotter wave buoy deployed along the south arm of the Great Salt Lake, near Antelope Island State Park from the period of July 13, 2021 through June 28, 2022, in relatively shallow water, approximately 1.6m.

IMPORTANT NOTE: Water depths for #1328 (Miera Spit) started at ~1.7 m, but dropped rapidly to 0.9 m on July 15, 2021 and dropped further to ~0.4 m on August 17, 2021. The timing of these rapid water depth changes matches the timing of buoy location changes when the anchor was dragged inshore by waves. When …

Spot1356 Black Rock, Robert C. Mahon, Elizabeth J. Trower, Benjamin P. Smith, Tyler A. Lincoln, Juliana Olsen-Valdez, John S. Magyar, Cedric J. Hagen

2D Wave Spectral Data, South Arm, Great Salt Lake, Utah

Data in this folder are produced by a SoFarOcean Spotter wave buoy deployed along the south arm of the Great Salt Lake, near Antelope Island State Park from the period of July 13, 2021 through June 28, 2022, in relatively shallow water, approximately 1.6m.

Spot1356 Black Rock Derived Data, Robert C. Mahon, Elizabeth J. Trower, Benjamin P. Smith, Tyler A. Lincoln, Juliana Olsen-Valdez, John S. Magyar, Cedric J. Hagen

2D Wave Spectral Data, South Arm, Great Salt Lake, Utah

Data in this folder are produced by a SoFarOcean Spotter wave buoy deployed along the south arm of the Great Salt Lake, near Antelope Island State Park from the period of July 13, 2021 through June 28, 2022, in relatively shallow water, approximately 1.6m.

Evaluation Of Zero-Net-Rate Pumping Tests, Austin Smith-Jones

All Theses

Accurately estimating the distribution of aquifer properties is key to understanding contaminant movement in the subsurface. The distribution of aquifer properties is typically addressed using slug or constant-rate well tests, and the pros and cons of these tests are well known. Slug tests are appealing because they avoid removing contaminated water, but their results are affected by well skin and the small volume of displaced water limits the volume of aquifer that can be evaluated. Constant-rate well tests have the disadvantage of requiring disposal of potentially contaminated water, but they can generate properties that are more representative than slug tests, …

Applications Of High-Precision U-Pb Geochronology: Innovations And Insights Into Super-Eruption Petrochronology, Chronostratigraphy, And Linking Large Igneous Provinces, Michael T. Mohr

Boise State University Theses and Dissertations

The perpetual and persistent forward march of time is a geoscientist’s reference frame for understanding Earth’s natural changes that manifest in all scales of natural materials (e.g., minerals, fossils, glaciers, rocks, mountain belts, cratons). While indicators of relative timing can be abundant in natural materials (e.g., stratigraphic superposition, cross-cutting relationships, crystal growth zonation), numerical timing constraints are required to contextualize and constrain the ordering, duration, and rate of Earth system processes. For investigating Earth processes in deep time, radioisotopic ages provide a temporal foundation for deciphering the clues from an often fragmented and incomplete rock record. Among the radioisotope chronometers, …

Predictive Modeling Of Cave Entrance Locations: Relationships Between Surface And Subsurface Morphology, William Blitch, Adia R. Sovie, Benjamin Tobin

Faculty, Staff, and Affiliated Publications--KGS

Cave entrances directly connect the surface and subsurface geomorphology in karst landscapes. Understanding the spatial distribution of these features can help identify areas on the landscape that are critical to flow in the karst groundwater system. Sinkholes and springs are major locations of inflow and outflow from the groundwater system, respectively, however not all sinkholes and springs are equally connected to the main conduit system.

Predicting where on the landscape zones of high connectivity exist is a challenge because cave entrances are difficult to detect and imperfectly documented. Wildlife research has a similar issue of understanding the complexities of where …

The Impact Of Glacial Proximity On The Elemental Composition Of Leachate Derived From Sediment Weathering, Karoline Ford

Theses/Capstones/Creative Projects

This study assesses chemical weathering trends as they relate to glacial retreat. The chemical environment of surfaces exposed to the atmosphere differs significantly from beneath a glacier. As a glacier melts, changes to the biogeochemical processes generate environmental gradients. This study analyzed chemical weathering signals at different distances from a glacial front by comparing the elemental composition of leachate derived from sediments in southeastern Greenland. Samples from proglacial, nonglacial, and moraine locations were weathered in a laboratory setting, and ion chromatography was used to determine the elemental composition of the products. Divergent trends in leachate composition were observed as distance …

Hydrothermal Fluid Transport Pathways Along Fractures And Veins At Brothers Volcano, Southern Kermadec Arc, Robert Atnip

Master's Theses

Hydrothermal fluid flow in fractures and veins is a key component in the mineralization of economic metals within calderas. But there are several methods by which fractures can form. Regional extension, episodic caldera collapse, and fluid overpressure all have the potential to create brittle features. Current studies focus on the formation of fractures and veins by these methods, but do not focus on the preferred movement of hydrothermal fluids through brittle features, nor which features are more dominant in active hydrothermal systems. This thesis introduces multiple studies to better understand which method of fracture creation dominates Brothers volcano. Data from …