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Palynostratigraphy And Bayesian Age Stratigraphic Model Of New Ca-Id-Tims Zircon Ages From The Walloon Coal Measures, Surat Basin, Australia, K. Sobczak, J. Cooling, T. Crossingham, H. G. Holl, M. Reilly, J. Esterle, J. L. Crowley, C. Hannaford, M. T. Mohr, Z. Hamerli, S. Hurter 2024 University of Queensland

Palynostratigraphy And Bayesian Age Stratigraphic Model Of New Ca-Id-Tims Zircon Ages From The Walloon Coal Measures, Surat Basin, Australia, K. Sobczak, J. Cooling, T. Crossingham, H. G. Holl, M. Reilly, J. Esterle, J. L. Crowley, C. Hannaford, M. T. Mohr, Z. Hamerli, S. Hurter

Geosciences Faculty Publications and Presentations

The Surat Basin hosts significant coal and coal seam gas resources. New high-precision CA-TIMS U/Pb zircon ages from tuffs and Bayesian age stratigraphic models are combined with palynology from fine-grained sedimentary rocks and zircon trace elements to provide further chronostratigraphic and biostratigraphic constrains on the Walloon Coal Measures in the eastern margin of the Surat Basin and infer the palaeoenvironment and tectonic setting. The tuff ages range from 165.88 ± 0.11 Ma to 158.84 ± 0.05 Ma, with those from the stratigraphically lower Taroom Coal Measures ranging from 165.88 ± 0.11 to 163.05 ± 0.08 Ma and Juandah Coal Measures …


Deformation Mapping And Modeling Of The Aleutian Volcanoes With Insar And Numerical Models, Jiahui Wang 2024 Southern Methodist University

Deformation Mapping And Modeling Of The Aleutian Volcanoes With Insar And Numerical Models, Jiahui Wang

Earth Sciences Theses and Dissertations

Surface deformation mapping is an essential component for comprehensive monitoring of volcanic activities, serving as a vital tool for discerning crucial insights into magma dynamics, storage, and migration for accurate hazard forecasting, assessment, and mitigation. However, monitoring of the volcanic deformation across the Aleutian volcanic arc is usually limited by the lack of terrestrial sensors deployed due to their remote locations and hostile environmental conditions, necessitating alternative methodologies for data acquisition and analysis.

My PhD study aims at precisely mapping the crustal deformation for the Aleutian volcanoes and tracking the evolution of the magmatic system with Interferometric Synthetic Aperture Radar …


Effect Of Biomass Water Dynamics In Cosmic-Ray Neutron Sensor Observations: A Long-Term Analysis Of Maize-Soybean Rotation In Nebraska, Tanessa Morris 2024 University of Nebraska-Lincoln

Effect Of Biomass Water Dynamics In Cosmic-Ray Neutron Sensor Observations: A Long-Term Analysis Of Maize-Soybean Rotation In Nebraska, Tanessa Morris

School of Natural Resources: Dissertations, Theses, and Student Research

The precise measurement of soil water content (SWC) is crucial for effective water resource management. This study utilizes the Cosmic Ray Neutron Sensor (CRNS) for area-averaged SWC measurements, emphasizing the need to consider all hydrogen sources, including the time-variable ones like plant biomass and water content. Chapter 1 presents a background on soil moisture estimation, CRNS technology, and an overview of the study. It discusses various soil moisture measurement techniques, highlights the gap in knowledge addressed by CRNS technology, explains CRNS functionality and advancements, and outlines the study's motivations and methods.

Chapter 2 reports a study conducted near Mead, Nebraska, …


A Laser Ultrasound System To Non-Invasively Measure Compression Waves In Granular Ice Mixes, J. Chris McCaslin, T. Dylan Mikesell, Hans-Peter Marshall 2024 Boise State University

A Laser Ultrasound System To Non-Invasively Measure Compression Waves In Granular Ice Mixes, J. Chris Mccaslin, T. Dylan Mikesell, Hans-Peter Marshall

Geosciences Faculty Publications and Presentations

Accurate knowledge of snow mechanical properties, including Young's modulus, shear modulus, Poisson's ratio, and density, is critical to many areas of snow science and to snow-related engineering problems. To facilitate the assessment of these properties, an innovative non-contacting laser ultrasound system (LUS) has been developed. This system acquires ultrasound waveform data at frequencies ranging from tens to hundreds of kHz in a controlled cold-lab environment. Two different LUS devices were compared in this study to determine which recorded more robust ultrasound in granular ice mix samples. We validated the ultrasound observations with poro-elastic traveltime modeling based on physical and empirical …


A Cold Laboratory Hyperspectral Imaging System To Map Grain Size And Ice Layer Distributions In Firn Cores, Ian E. McDowell, Kaitlin M. Keegan, S. McKenzie Skiles, Christopher P. Donahue, Erich C. Osterberg, Robert L. Hawley, Hans-Peter Marshall 2024 University of Nevada, Reno

A Cold Laboratory Hyperspectral Imaging System To Map Grain Size And Ice Layer Distributions In Firn Cores, Ian E. Mcdowell, Kaitlin M. Keegan, S. Mckenzie Skiles, Christopher P. Donahue, Erich C. Osterberg, Robert L. Hawley, Hans-Peter Marshall

Geosciences Faculty Publications and Presentations

The Greenland and Antarctic ice sheets are covered in a layer of porous firn. Knowledge of firn structure improves our understanding of ice sheet mass balance, supra- and englacial hydrology, and ice core paleoclimate records. While macroscale firn properties, such as firn density, are relatively easy to measure in the field or lab, more intensive measurements of microstructural properties are necessary to reduce uncertainty in remote sensing observations of mass balance, model meltwater infiltration, and constrain ice age – gas age differences in ice cores. Additionally, as the duration and extent of surface melting increases, refreezing meltwater will greatly alter …


Estimating Crustal Thickness In Northwest Louisiana Using The Receiver Function Method, Delton Samuel 2024 Louisiana State University

Estimating Crustal Thickness In Northwest Louisiana Using The Receiver Function Method, Delton Samuel

LSU Master's Theses

I aim to constrain the crustal thickness of the Sabine Block in the Sabine Uplift region of northwest Louisiana, using the frequency domain receiver function deconvolution technique followed by H-κ stacking. The passive margin on the southern edge of the North American continent experienced an active tectonic history, including the spreading events that led to the formation of the Gulf of Mexico. A previous study proposed the Sabine Block is a residual fragment of Proterozoic orogenic origin; however, its full extent and geometry are up for debate. It is now overlain by thick sedimentary sequences ranging from ~4-6 km deposited …


Paleozoic Evolution Of The Yukon-Tanana Terrane Of The North American Cordillera, Nw British Columbia, R. Soucy La Roche, A. Zagorevski, N. L. Joyce, J. L. Crowley 2024 Institut National de la Recherche Scientifique

Paleozoic Evolution Of The Yukon-Tanana Terrane Of The North American Cordillera, Nw British Columbia, R. Soucy La Roche, A. Zagorevski, N. L. Joyce, J. L. Crowley

Geosciences Faculty Publications and Presentations

The origins and primary relationships between tectono-stratigraphic units are fundamental to the terrane concept in accretionary orogens, but they are challenging to assess in metamorphic terranes. In NW British Columbia, three tectonically bounded metamorphic suites of the Yukon-Tanana terrane formed in distinct tectonic settings, based on high-spatial-resolution geochronology and immobile trace-element geochemistry. The Florence Range suite comprises late Neoproterozoic or younger to pre–latest Devonian metasedimentary rocks derived from continental crust, 360 ± 4 Ma calc-alkaline intermediate orthogneiss, and 357 ± 4 Ma amphibolite with oceanic-island basalt composition, consistent with rifting of a continental margin. The detrital signature is dominated by …


Influence Of Subsurface Critical Zone Structure On Hydrological Partitioning In Mountainous Headwater Catchments, Hang Chen, Qifei Niu, James P. McNamara, Alejandro N. Flores 2024 Boise State University

Influence Of Subsurface Critical Zone Structure On Hydrological Partitioning In Mountainous Headwater Catchments, Hang Chen, Qifei Niu, James P. Mcnamara, Alejandro N. Flores

Geosciences Faculty Publications and Presentations

Headwater catchments play a vital role in regional water supply and ecohydrology, and a quantitative understanding of the hydrological partitioning in these catchments is critically needed, particularly under a changing climate. Recent studies have highlighted the importance of subsurface critical zone (CZ) structure in modulating the partitioning of precipitation in mountainous catchments; however, few existing studies have explicitly taken into account the 3D subsurface CZ structure. In this study, we designed realistic synthetic catchment models based on seismic velocity-estimated 3D subsurface CZ structures. Integrated hydrologic modeling is then used to study the effects of the shape of the weathered bedrock …


Enhancing Landslide Susceptibility Modelling Through A Novel Non-Landslide Sampling Method And Ensemble Learning Technique, Chao Zhou, Yue Wang, Ying Cao, Ramesh P. Singh, Bayes Ahmed, Mahdi Motagh, Yang Wang, Ling Chen, Guangchao Tan, Shanshan Li 2024 China University of Geosciences Wuhan

Enhancing Landslide Susceptibility Modelling Through A Novel Non-Landslide Sampling Method And Ensemble Learning Technique, Chao Zhou, Yue Wang, Ying Cao, Ramesh P. Singh, Bayes Ahmed, Mahdi Motagh, Yang Wang, Ling Chen, Guangchao Tan, Shanshan Li

Mathematics, Physics, and Computer Science Faculty Articles and Research

In recent years, several catastrophic landslide events have been observed throughout the globe, threatening to lives and infrastructures. To minimize the impact of landslides, the need of landslide susceptibility map is important. The study aims to extract high-quality non-landslide samples and improve the accuracy of landslide susceptibility modelling (LSM) outcomes by applying a coupled method of ensemble learning and Machine Learning (ML). The Zigui-Badong section of the Three Gorges Reservoir area (TGRA) in China was considered in the present study. Twelve influencing factors were selected as inputs for LSM, and the relationship between each causal factor and landslide spatial development …


Investigation Of Gas Dynamics In Water And Oil-Based Muds Using Das, Dts, And Dss Measurements, Temitayo S. Adeyemi 2024 Louisiana State University at Baton Rouge

Investigation Of Gas Dynamics In Water And Oil-Based Muds Using Das, Dts, And Dss Measurements, Temitayo S. Adeyemi

LSU Master's Theses

Reliable prediction of gas migration velocity, void fraction, and length of gas-affected region in water and oil-based muds is essential for effective planning, control, and optimization of drilling operations. However, there is a gap in our understanding of gas behavior and dynamics in water and oil-based muds. This is a consequence of the use of experimental systems that are not representative of field-scale conditions. This study seeks to bridge the gap via the well-scale deployment of distributed fiber-optic sensors for real-time monitoring of gas behavior and dynamics in water and oil-based mud. The aforementioned parameters were estimated in real-time using …


The Study Of Titan's Surface Using Impact Craters And Analogues, Jahnavi Shah 2024 University of Western Ontario

The Study Of Titan's Surface Using Impact Craters And Analogues, Jahnavi Shah

Electronic Thesis and Dissertation Repository

Titan, Saturn’s largest moon, is an icy world harbouring a subsurface water ocean, a substantial atmosphere, and a flowing liquid on its surface. These distinctive characteristics give rise to complex chemical reactions on Titan, and also render it akin to Earth in terms of its landforms and processes. This positions Titan as a key target for studying prebiotic chemistry. NASA's fourth New Frontiers mission, Dragonfly, is poised to explore Titan’s surface in the 2030s. Dragonfly’s primary study site will be Selk crater, a relatively fresh impact crater located in Titan’s equatorial sand seas. Impact craters serve as valuable markers for …


High-Precision U-Pb Geochronology Links Magmatism In The Southwestern Laurentia Large Igneous Province And Midcontinent Rift, M. T. Mohr, M. D. Schmitz, N. L. Swanson-Hysell, K. E. Karlstrom, F. A. Macdonald, M. E. Holland, Y. Zhang, N. S. Anderson 2024 Boise State University

High-Precision U-Pb Geochronology Links Magmatism In The Southwestern Laurentia Large Igneous Province And Midcontinent Rift, M. T. Mohr, M. D. Schmitz, N. L. Swanson-Hysell, K. E. Karlstrom, F. A. Macdonald, M. E. Holland, Y. Zhang, N. S. Anderson

Geosciences Faculty Publications and Presentations

The Southwestern Laurentia large igneous province (SWLLIP) comprises voluminous, widespread ca 1.1 Ga magmatism in the southwestern United States and northern Mexico. The timing and tempo of SWLLIP magmatism and its relationship to other late Mesoproterozoic igneous provinces have been unclear due to difficulties in dating mafic rocks at high precision. New precise U-Pb zircon dates for comagmatic felsic segregations within mafic rocks reveal distinct magmatic episodes at ca. 1098 Ma (represented by massive sills in Death Valley, California, the Grand Canyon, and central Arizona) and ca. 1083 Ma (represented by the Cardenas Basalts in the Grand Canyon and a …


Snow Water Equivalent Retrieval Over Idaho – Part 2: Using L-Band Uavsar Repeat-Pass Interferometry, Zachary Hoppinen, Shadi Oveisgharan, Hans-Peter Marshall, Ross Mower, Kelly Elder, Carrie Vuyovich 2024 Boise State University

Snow Water Equivalent Retrieval Over Idaho – Part 2: Using L-Band Uavsar Repeat-Pass Interferometry, Zachary Hoppinen, Shadi Oveisgharan, Hans-Peter Marshall, Ross Mower, Kelly Elder, Carrie Vuyovich

Geosciences Faculty Publications and Presentations

This study evaluates using interferometry on low-frequency synthetic aperture radar (SAR) images to monitor snow water equivalent (SWE) over seasonal and synoptic scales. We retrieved SWE changes from nine pairs of SAR images, mean 8 d temporal baseline, captured by an L-band aerial platform, NASA's Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR), over central Idaho as part of the NASA SnowEx 2020 and 2021 campaigns. The retrieved SWE changes were compared against coincident in situ measurements (SNOTEL and snow pits from the SnowEx field campaign) and to 100 m gridded SnowModel modeled SWE changes. The comparison of in situ to …


Snow Water Equivalent Retrieval Over Idaho – Part 1: Using Sentinel-1 Repeat-Pass Interferometry, Shadi Oveisgharan, Robert Zinke, Zachary Hoppinen, Hans Peter Marshall 2024 California Institute of Technology

Snow Water Equivalent Retrieval Over Idaho – Part 1: Using Sentinel-1 Repeat-Pass Interferometry, Shadi Oveisgharan, Robert Zinke, Zachary Hoppinen, Hans Peter Marshall

Geosciences Faculty Publications and Presentations

Snow water equivalent (SWE) is identified as the key element of the snowpack that impacts rivers' streamflow and water cycle. Both active and passive microwave remote sensing methods have been used to retrieve SWE, but there does not currently exist a SWE product that provides useful estimates in mountainous terrain. Active sensors provide higher-resolution observations, but the suitable radar frequencies and temporal repeat intervals have not been available until recently. Interferometric synthetic aperture radar (InSAR) has been shown to have the potential to estimate SWE change. In this study, we apply this technique to a long time series of 6 …


Deep Structure Of Siletzia In The Puget Lowland: Imaging An Obducted Plateau And Accretionary Thrust Belt With Potential Fields, Megan L. Anderson, Richard J. Blakely, Ray E. Wells, Joe D. Dragovich 2024 Washington Geological Survey

Deep Structure Of Siletzia In The Puget Lowland: Imaging An Obducted Plateau And Accretionary Thrust Belt With Potential Fields, Megan L. Anderson, Richard J. Blakely, Ray E. Wells, Joe D. Dragovich

Geology Faculty Publications and Presentations

Detailed understanding of crustal components and tectonic history of forearcs is important due to their geological complexity and high seismic hazard. The principal component of the Cascadia forearc is Siletzia, a composite basaltic terrane of oceanic origin. Much is known about the lithology and age of the province. However, glacial sediments blanketing the Puget Lowland obscure its lateral extent and internal structure, hindering our ability to fully understand its tectonic history and its influence on modern deformation. In this study, we apply map-view interpretation and two-dimensional modeling of aeromagnetic and gravity data to the magnetically stratified Siletzia terrane revealing its …


Geothermal Play Fairway Analysis, Part 2: Gis Methodology, Jacob DeAngelo, John W. Shervais, Jonathan M. Glen, Dennis Nielson, Sabodh Garg, Patrick F. Dobson, Erika Gasperikova, Eric Sonnenthal, Lee M. Liberty, Drew L. Siler, James P. Evans 2024 U.S. Geological Survey

Geothermal Play Fairway Analysis, Part 2: Gis Methodology, Jacob Deangelo, John W. Shervais, Jonathan M. Glen, Dennis Nielson, Sabodh Garg, Patrick F. Dobson, Erika Gasperikova, Eric Sonnenthal, Lee M. Liberty, Drew L. Siler, James P. Evans

Geosciences Faculty Publications and Presentations

Play Fairway Analysis (PFA) in geothermal exploration originates from a systematic methodology developed within the petroleum industry and is based on a geologic, geophysical, and hydrologic framework of identified geothermal systems. We tailored this methodology to study the geothermal resource potential of the Snake River Plain and surrounding region, but it can be adapted to other geothermal resource settings. We adapted the PFA approach to geothermal resource exploration by cataloging the critical elements controlling exploitable hydrothermal systems, establishing risk matrices that evaluate these elements in terms of both probability of success and level of knowledge, and building a code-based ‘processing …


Chronostratigraphy Of Miocene Strata In The Berkeley Hills (California Coast Ranges, Usa) And The Arrival Of The San Andreas Transform Boundary, Stacey H. Gerasimov, Eben B. Hodgin, James L. Crowley, Nicholas L. Swanson-Hysell 2024 University of California

Chronostratigraphy Of Miocene Strata In The Berkeley Hills (California Coast Ranges, Usa) And The Arrival Of The San Andreas Transform Boundary, Stacey H. Gerasimov, Eben B. Hodgin, James L. Crowley, Nicholas L. Swanson-Hysell

Geosciences Faculty Publications and Presentations

Miocene strata of the Claremont, Orinda, and Moraga formations of the Berkeley Hills (California Coast Ranges, USA) record sedimentation and volcanism during the passage of the Mendocino triple junction and early evolution of the San Andreas fault system. Detrital zircon laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) age spectra indicate a change in sedimentary provenance between the marine Claremont formation (Monterey Group) and the terrestrial Orinda and Moraga Formations associated with uplift of Franciscan Complex lithologies. A sandstone from the Claremont formation produced a detrital zircon chemical abrasion–isotope dilution–thermal ionization mass spectrometry (CA-ID-TIMS) maximum depositional age of 13.298 ± 0.046 Ma, …


Geotechnical Characterisation Of Coal Spoil Piles Using High-Resolution Optical And Multispectral Data: A Machine Learning Approach, Sureka Thiruchittampalam, Bikram Pratap Banerjee, Nancy F. Glenn, Simit Raval 2024 University of New South Wales

Geotechnical Characterisation Of Coal Spoil Piles Using High-Resolution Optical And Multispectral Data: A Machine Learning Approach, Sureka Thiruchittampalam, Bikram Pratap Banerjee, Nancy F. Glenn, Simit Raval

Geosciences Faculty Publications and Presentations

Geotechnical characterisation of spoil piles has traditionally relied on the expertise of field specialists, which can be both hazardous and time-consuming. Although unmanned aerial vehicles (UAV) show promise as a remote sensing tool in various applications; accurately segmenting and classifying very high-resolution remote sensing images of heterogeneous terrains, such as mining spoil piles with irregular morphologies, presents significant challenges. The proposed method adopts a robust approach that combines morphology-based segmentation, as well as spectral, textural, structural, and statistical feature extraction techniques to overcome the difficulties associated with spoil pile characterisation. Additionally, it incorporates minimum redundancy maximum relevance (mRMR) based feature …


Geothermal Play Fairway Analysis, Part 1: Example From The Snake River Plain, Idaho, John W. Shervais, Jacob DeAngelo, Jonathan M. Glen, Dennis L. Nielson, Sabodh Garg, Patrick Dobson, Erika Gasperikova, Eric Sonnenthal, Lee M. Liberty, Dennis L. Newell, Drew Siler, James P. Evans 2024 Utah State University

Geothermal Play Fairway Analysis, Part 1: Example From The Snake River Plain, Idaho, John W. Shervais, Jacob Deangelo, Jonathan M. Glen, Dennis L. Nielson, Sabodh Garg, Patrick Dobson, Erika Gasperikova, Eric Sonnenthal, Lee M. Liberty, Dennis L. Newell, Drew Siler, James P. Evans

Geosciences Faculty Publications and Presentations

The Snake River Plain (SRP) volcanic province overlies the track of the Yellowstone hotspot, a thermal anomaly that extends deep into the mantle. Most of the area is underlain by a basaltic volcanic province that overlies a mid-crustal intrusive complex, which in turn provides the long-term heat flux needed to sustain geothermal systems. Previous studies have identified several known geothermal resource areas within the SRP. For the geothermal study presented herein, our goals were to: (1) adapt the methodology of Play Fairway Analysis (PFA) for geothermal exploration to create a formal basis for its application to geothermal systems, (2) assemble …


Zircon And The Role Of Magmatic Petrogenesis In The Formation Of Felsic-Hosted Volcanogenic Massive Sulfide (Vms) Deposits: A Case Study From The Mid-Paleozoic Yukon-Tanana Terrane, Northern Canadian Cordillera, Matthew J. Manor, Stephen J. Piercey, Corey J. Wall 2024 Memorial University of Newfoundland

Zircon And The Role Of Magmatic Petrogenesis In The Formation Of Felsic-Hosted Volcanogenic Massive Sulfide (Vms) Deposits: A Case Study From The Mid-Paleozoic Yukon-Tanana Terrane, Northern Canadian Cordillera, Matthew J. Manor, Stephen J. Piercey, Corey J. Wall

Geosciences Faculty Publications and Presentations

Magmatism is a critical component in sustaining hydrothermal convection and metal transport during the formation of volcanogenic massive sulfide (VMS) deposits. Previous studies of magmatic petrogenesis in VMS systems have demonstrated that ore-related volcanic rocks have distinct whole-rock geochemical and isotopic signatures (i.e., high HFSE, REE, Th, εHf-Nd, zircon saturation T) relative to barren volcanic rocks, which supports models of elevated crustal heat flow during periods of ore deposition; however, the petrologic characteristics and intrinsic parameters (e.g., T, fO2) related to these magmatic events in VMS districts remain poorly understood. Arc–back-arc assemblages from the mid-Paleozoic Yukon-Tanana terrane …


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