Kinematic Vorticity And Porphyroclast Rotation In Mylonites Of The Norumbega Fault System: Implications For Paleoviscometry,
2023
University of Maine - Main
Kinematic Vorticity And Porphyroclast Rotation In Mylonites Of The Norumbega Fault System: Implications For Paleoviscometry, Hendrik Lenferink
Honors College
Crystallographic and shape preferred orientation (SPO) fabrics that develop in mylonitic shear zones can preserve the mean kinematic vorticity number (Wm) of bulk flow. Microstructural methods exploiting dynamically recrystallized quartz and porphyroclast SPO fabrics typically yield conflicting values of Wm. The Sandhill Corner Mylonite Zone of the Norumbega Fault System, Maine, USA, serves as a case study for investigating this discrepancy; Wm estimates range from 0.90 to 1.00 employing the former method (Method 1) and from 0.3 to 0.6 employing the latter method (Method 2). Using a numerical model, I show how a low-viscosity layer (LVL) surrounding clasts affects their …
Tropical Atlantic Temperature And Hydrologic Shifts During The Paleocene-Eocene Thermal Maximum,
2023
Utah State University
Tropical Atlantic Temperature And Hydrologic Shifts During The Paleocene-Eocene Thermal Maximum, Chels Howard
All Graduate Theses and Dissertations, Fall 2023 to Present
The Paleocene-Eocene Thermal Maximum (PETM) is a geologic climate event that is studied heavily due to the similarities to anthropogenic climate change. This event occurred approximately 56 million years ago (Ma) and is characterized by a rapid release of carbon into the atmosphere, which resulted in an increase in temperature and a change in global climate events such as changes in patterns of evaporation and precipitation. We see this effect occurring in modern anthropogenic climate change due to the burning of fossil fuels releasing carbon dioxide (CO2) into the atmosphere. In this study I use elemental data of …
Constraining Silicate Weathering During The Middle Eocene Climatic Optimum (Meco) Using Radiolarian Ge/Si,
2023
Utah State University
Constraining Silicate Weathering During The Middle Eocene Climatic Optimum (Meco) Using Radiolarian Ge/Si, Olivia R. Laub
All Graduate Theses and Dissertations, Fall 2023 to Present
Silicate weathering has long been considered a fundamental component of the earth system and has been cited as one of, if not the primary stabilizing feedback for climate. However, recent work has shown that the role of silicate weathering in the climate system is more complicated and dynamic than previously assumed. In this study I examine the role of weathering in the enigmatic warming event, the Middle Eocene Climatic Optimum (MECO) that occurred approximately 40 Ma. This event works as a good case study as there are multiple features of the MECO that differentiate it from other warming events that …
Landscape/Atmosphere Interactions And Carbon-Dioxide Dynamics In The Great Onyx Groundwater Basin, Mammoth Cave National Park, Kentucky,
2023
Western Kentucky University
Landscape/Atmosphere Interactions And Carbon-Dioxide Dynamics In The Great Onyx Groundwater Basin, Mammoth Cave National Park, Kentucky, Meghan Raines
Masters Theses & Specialist Projects
An increase in atmospheric CO2 since the Industrial Revolution has altered rates of global climate change and has motivated a need to better quantify the flux of carbon between Earth’s reservoirs. Attempts to quantify the exchange of atmospheric carbon between sources and sinks have led to an increasing interest in the terrestrial landscape, including the continental carbon sink associated with carbonate-mineral dissolution. This research sought to better inform an understanding of karst landscapes and their relationship with global climate change through carbon cycling. The study utilized high-resolution data collection of pH, temperature, and specific conductance of waters in the Cascade …
Electrofacies Analysis Using A Geostatistical Approach, Northern Iraq Case Study,
2023
Department of Petroleum Geosciences, Faculty of Science, Soran University, Soran, Erbil, Iraq
Electrofacies Analysis Using A Geostatistical Approach, Northern Iraq Case Study, Hussein S. Hussein
Polytechnic Journal
The distribution of petrophysical parameters is governed by lithology, hence understanding the spatial variation in lithology is essential for reservoir characterisation. This study points out the use of well logs to estimate the lithology of carbonate rocks (limestone, marly limestone, dolomite, and dolomitic limestone) found in Upper Cretaceous to Miocene formations at the Khabbaz Oil Field in Northern Iraq. Applying the multivariate regression technique to neutron, and density data enabled accurate lithology prediction. By using independent values (well log data) to predict a dependent value (lithology), this technique is a progression of regression analysis. The formations under study comprised a …
Determining The P-Wave Velocity Structure In The Near-Surface Of Nw Miami, Florida, Using Quarry Blasts,
2023
University of South Florida
Determining The P-Wave Velocity Structure In The Near-Surface Of Nw Miami, Florida, Using Quarry Blasts, Elham Moslemi
USF Tampa Graduate Theses and Dissertations
The fact that Florida is an earthquake-free region has caused seismologists to pay less attention to it. Few earthquakes in this state mean it is not a usual practice to study the propagation of seismic waves. However, utilizing data from quarry blasts, we studied wave propagation in this region. The primary objective of the project is to investigate the near-surface P-wave velocity structure and factors that may affect it. We also analyzed the amplitude of signals versus distance and blast size. A network of up to 10 Raspberry Shake instruments around the NW Miami-Lakes mining area was deployed where four …
Migmatite Formation, Geochronometer Petrogeneisis, And Rare Earth Element Mineralization In The Adirondack Mountains, Ny,
2023
University of Massachusetts Amherst
Migmatite Formation, Geochronometer Petrogeneisis, And Rare Earth Element Mineralization In The Adirondack Mountains, Ny, Kaitlyn Suarez
Doctoral Dissertations
The Adirondack Mountains in upstate New York contain exposures of complex partially melted rocks, in addition to iron oxide-apatite (IOA) deposits with variable rare earth element (REE) concentrations. Previous workers have suggested that melting occurred during the ca. 1150 Ma Shawinigan and the ca. 1050 Ma Ottawan orogenies. However, there are challenges in determining the timing of melting and the number of partial melt events. Further, tectonic models must be developed to describe the petrogenesis of IOA and REE mineralization. Migmatites are present along Rt. 4/22 near Whitehall, NY. In chapter two, all layers of a single migmatitic rock were …
Heat Flow In The Southern Margin Of Salar De Atacama: Deep Groundwater Temperature Distributions And The Implications For Subsurface Flow And Land Surface Energy Budgets,
2023
University of Massachusetts Amherst
Heat Flow In The Southern Margin Of Salar De Atacama: Deep Groundwater Temperature Distributions And The Implications For Subsurface Flow And Land Surface Energy Budgets, Graham Thomas
Masters Theses
Salar de Atacama (SdA) located in Northern Chile is home to one of the planet’s largest salar systems and lithium resources. Managing groundwater resources in salars is not obvious due to the lack of scientific understanding on the connectivity between the freshwater and brine systems. Using heat as a tracer in SdA provides a cost-effective method to further investigate groundwater flow in salars. This study employs 372 temperature-depth profiles from 90 boreholes between 2013-18 to understand the distinct thermal zones and flow between them in SdA. Three thermal zones exist within the southern margin of SdA’s thermal regime, at higher …
Examining Paleoshorelines In The Eastern Gulf Of Mexico: Insights On Sea Level History And Potential Areas Of Interest For Habitat Management,
2023
University of South Florida
Examining Paleoshorelines In The Eastern Gulf Of Mexico: Insights On Sea Level History And Potential Areas Of Interest For Habitat Management, Catalina Rubiano
USF Tampa Graduate Theses and Dissertations
An inventory of multibeam bathymetry containing relict drowned and lithified paleoshorelines has been compiled and analyzed in the first ever shelf-wide investigation of paleo sea level indicators on the west Florida shelf (WFS). On the largest scale, the WFS is a wide and gently sloping terrain that is characterized by a carbonate-rich sediment regime. This framework coupled with the region’s tectonic stability provided a setting in which sea level changes since ~ 20 ka have been recorded to a remarkable degree of resolution in the form of paleoshorelines which formed at sea level and were subsequently drowned and preserved in …
Kentucky Karst Dye Trace Database,
2023
University of Kentucky
Kentucky Karst Dye Trace Database, Sarah M. Arpin, Benjamin W. Tobin, Maaz Fareedi, Adam Link, James C. Currens
Research Data--KGS
This dataset provides the geographical locations of karst groundwater basins, groundwater flowpaths, and dye injection/recovery points in Kentucky. Dye tracing is a common method used for understanding groundwater movement. Dye is poured (or injected) into a sinking stream, well, sinkhole, or body of water, where it is carried down-gradient by flowing water. The locations at which dye is recovered (typically at artesian springs) indicates a connection from injection to recovery site. This connection is refered to as a groundwater flowpath. Conducting multiple dye traces across an area allows for the interpretation of regional groundwater flow by assessing where flowpaths either …
Kgs Joint Data,
2023
University of Kentucky
Kgs Joint Data, Steven L. Martin
Research Data--KGS
Joint orientation measurements collected by KGS personnel at rock exposures from 2009 to 2023. New joint data was collected using a Brunton compass. This data set is a compilation of joints measured by Steve Martin. There are three worksheets related to data structure. The joint location and joint measurement worksheets show a 1-to-many relationship. The 1to1 worksheet shows a 1-to-1 relationship between joint locations and measurements.
Review Of Harmful Algal Bloom Effects On Birds With Implications For Avian
Wildlife In The Chesapeake Bay Region,
2023
U.S. Geological Survey
Review Of Harmful Algal Bloom Effects On Birds With Implications For Avian Wildlife In The Chesapeake Bay Region, Barnett A. Rattner, Catherine E. Wazniak, Julia S. Lankton, Peter C. Mcgowan, Serguei V. Drovetski, Todd A. Egerton
United States Geological Survey: Staff Publications
The Chesapeake Bay, along the mid-Atlantic coast of North America, is the largest estuary in the United States and provides critical habitat for wildlife. In contrast to point and non-point source release of pesticides, metals, and industrial, personal care and household use chemicals on biota in this watershed, there has only been scant attention to potential exposure and effects of algal toxins on wildlife in the Chesapeake Bay region. As background, we first review the scientific literature on algal toxins and harmful algal bloom (HAB) events in various regions of the world that principally affected birds, and to a lesser …
Deformation And Evolution Of Achondrite Parent Bodies,
2023
Western University
Deformation And Evolution Of Achondrite Parent Bodies, Yaozhu Li
Electronic Thesis and Dissertation Repository
Minerals in planetary bodies record accumulated strain from deformation events such as hypervelocity impacts but potentially also parent body processes such as gravitational compaction. This work investigates olivine microstructural features that may distinguish between different impact levels versus parent body plastic deformation regimes. Achondritic meteorites from the ureilite parent body, the Moon, Mars as well as terrestrial basalt and mantle xenolith have been investigated using micro-XRD, EBSD, micro-XRF and other methods to study their parent body deformation history. A Matlab® method, unit segment length (USL), is herein developed to visualize the crystal boundary geometry and quantify the apparent subboundary density …
Restoration And Balancing Of A Cross Section Of The Mt. Crandell Duplex, Waterton National Park, Canada,
2023
DePauw University
Restoration And Balancing Of A Cross Section Of The Mt. Crandell Duplex, Waterton National Park, Canada, Danielle Sommerman, M. Scott Wilkerson
Student Research
Cross-section balancing provides a useful tool for checking the potential viability of structural interpretations through complexly deformed terranes. Balanced cross sections contain structures that are similar to those observed in outcrop or on seismic profiles in the area, that can be restored to a realistic pre-deformational configuration of faults and undeformed strata where areas are preserved between the deformed and restored states, and whose development from the undeformed state can be described in a kinematically reasonable sequence. Quick-look inspection of cross sections greatly facilitates the balancing process by comparing corresponding hanging wall and footwall features (particularly focusing on ramps and …
Aroutcrop: An Augmented Reality Mobile Application For Enhancing Geoscience Learning And Comprehension In The Field And Classroom,
2023
DePauw University
Aroutcrop: An Augmented Reality Mobile Application For Enhancing Geoscience Learning And Comprehension In The Field And Classroom, Benjamin S. Wilkerson, Zachary Wilkerson, M. Scott Wilkerson
Student Research
Most geologists have long recognized the educational value of immersive opportunities and hands-on experiences that teaching geology in the field and using natural rock samples in the classroom offer students. However, these instructional approaches also give rise to distinct logistical and pedagogical challenges. For example, in the field, students sometimes struggle to fully connect concepts, models, and interpretations from classroom lectures with seemingly amorphous masses of rock that they encounter. Or, in the classroom, students may only have limited time for analysis when passing individual hand specimens person-to-person, and may not have access to valuable or fragile samples outside of …
Hydrochemistry Of An Alpine Karst System, Northern New Mexico: Las Huertas,
2023
The University of New Mexico
Hydrochemistry Of An Alpine Karst System, Northern New Mexico: Las Huertas, Kambray A. Townsend
Earth and Planetary Sciences ETDs
Las Huertas in the Sandia Mountains relies on snowmelt, monsoonal recharge, and groundwater inputs. Our hypothesis, the proportion of groundwater contribution varied spatially and temporally, was assessed by observing travertine and multiple geochemical tracers to differentiate water balance components. We report 26 samples from 13 locations (sampled between 2021-2023). Major ion and isotopic analysis indicated Las Huertas headsprings vary spatially. Capulin Spring has higher salinity; major ions suggest recharged waters are a mix of CaCO3-rich and sulfate-chloride-containing water. The proportion of groundwater to spring discharge is a mix of winter and summer precipitation. Travertine supersaturation is seasonal, with variations downstream, …
Reducing Uncertainty In Sea-Level Rise Prediction: A Spatial-Variability-Aware Approach,
2023
University of Minnesota - Twin Cities
Reducing Uncertainty In Sea-Level Rise Prediction: A Spatial-Variability-Aware Approach, Subhankar Ghosh, Shuai An, Arun Sharma, Jayant Gupta, Shashi Shekhar, Aneesh Subramanian
I-GUIDE Forum
Given multi-model ensemble climate projections, the goal is to accurately and reliably predict future sea-level rise while lowering the uncertainty. This problem is important because sea-level rise affects millions of people in coastal communities and beyond due to climate change's impacts on polar ice sheets and the ocean. This problem is challenging due to spatial variability and unknowns such as possible tipping points (e.g., collapse of Greenland or West Antarctic ice-shelf), climate feedback loops (e.g., clouds, permafrost thawing), future policy decisions, and human actions. Most existing climate modeling approaches use the same set of weights globally, during either regression or …
Seabed Reflection Coefficient Variability In The Mono Lake Using Seismic Reflection Sparker Data,
2023
Southern Methodist University
Seabed Reflection Coefficient Variability In The Mono Lake Using Seismic Reflection Sparker Data, Francis Nnamdi Okeifufe
Earth Sciences Theses and Dissertations
Acoustic reflections from a lakebed provide valuable information about the dynamic boundary between water and the lakebed, where sediments and biota in the water column eventually settle. In this study, we present a comprehensive analysis of reflected sound wave amplitudes to gain insights into the physical properties of a water-sediment boundary. We decided to carry out this analysis within the unique ecosystem of the Mono Lake basin due to the fact that the Mono Lake, a meromictic and hypersaline waterbody is situated within one of the most active yet understudied volcanic regions in the United States. The fact that the …
Using Trace Element Concentrations In Volcanic Ash To Elucidate Magma Sources To Koma Kulshan’S (Mount Baker) Most Recent Explosive Eruption – The 6.7 Ka Ba (Black Ash) Tephra,
2023
Western Washington University
Using Trace Element Concentrations In Volcanic Ash To Elucidate Magma Sources To Koma Kulshan’S (Mount Baker) Most Recent Explosive Eruption – The 6.7 Ka Ba (Black Ash) Tephra, Stone Machel
Geology Graduate and Undergraduate Student Scholarship
Koma Kulshan (Mount Baker) is an active stratovolcano in the northern Washington Cascades. Kulshan’s most recent magmatic eruption at 6.7 ka was explosive, producing the ~0.2 km3 BA tephra (black ash) from the edifice (Scott et al. 2019). Comprehensive geochemical data for the BA tephra were previously limited to major elements from one whole rock lapillus (silicic andesite) and several in situ glass analyses (dacite), despite being Kulshan’s most voluminous Holocene tephra. Here, I present the first extensive major and trace element study of the pyroxene- and plagioclase-bearing BA tephra glass to determine magma source and eruption processes. My …
Geophysical Survey In Central North Dakota,
2023
University of North Dakota
Geophysical Survey In Central North Dakota, University Of North Dakota. Energy And Environmental Research Center
EERC Brochures and Fact Sheets
Fact sheet about a 2023–2024 Energy & Environmental Research Center (EERC) geophysical survey in central North Dakota to evaluate the feasibility of developing safe and permanent CO2 storage in the project area. Describes the purpose of the survey and potential impact on local landowners.
