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Articles 151 - 180 of 2451
Full-Text Articles in Geophysics and Seismology
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
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 …
Pcor Partnership Atlas, Wesley D. Peck, Kari Suedel, Kyle A. Glazewski, Kevin C. Connors, James A. Sorensen, Charles D. Gorecki, Brian P. Kalk, John A. Harju
Pcor Partnership Atlas, Wesley D. Peck, Kari Suedel, Kyle A. Glazewski, Kevin C. Connors, James A. Sorensen, Charles D. Gorecki, Brian P. Kalk, John A. Harju
EERC Maps and Infographics
The Plains CO2 Reduction (PCOR) Partnership Atlas provides a profile of CO2 sources and potential storage locations across the PCOR Partnership region. The revised sixth edition of the Atlas provides an up-to-date look at PCOR Partnership initiative activities, including additional regional characterization and updates on commercial projects. Additional background information on carbon capture, utilization, and storage (CCUS) is included to give a better understanding of how CCUS addresses concerns about climate change while allowing future energy needs to be met.
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
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
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
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 …
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
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 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
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 …
The Portable Hand Streamer: Rapid Seismic Imaging For Shallow Targets, Lee M. Liberty, L. Thomas Otheim
The Portable Hand Streamer: Rapid Seismic Imaging For Shallow Targets, Lee M. Liberty, L. Thomas Otheim
Geosciences Faculty Publications and Presentations
In this paper, we introduce a portable hand streamer seismic system. The system is appropriate for characterizing the mechanical properties of geologic and engineered materials in the upper 5 to 10 m depth and for reflection imaging from tens to hundreds of meters depth. Unlike other seismic land streamer systems that are typically pulled behind a vehicle with a long string of geophones, our recording system and electric seismic source are contained within an electric utility cart to allow ease of mobility for a single operator. Our 48-channel contact-coupled streamer is tethered to the cart to enable low-effort data collection. …
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
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 …
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
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, …
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
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 …
Spatial Analyses On Pre-Earthquake Ionospheric Anomalies And Magnetic Storms Observed By China Seismo-Electromagnetic Satellite In August 2018, Jann-Yeng Tiger Liu, Xuhui Shen, Fu-Yuan Chang, Yuh-Ing Chen, Yang-Yi Sun, Chieh‑Hung Chen, Sergey Pulinets, Katsumi Hattori, Dimitar Ouzounov, Valerio Tramutoli, Michel Parrot, Wei-Sheng Chen, Cheng-Yan Liu, Fei Zhang, Dapeng Liu, Xue-Min Zhang, Rui Yan, Qiao Wang
Spatial Analyses On Pre-Earthquake Ionospheric Anomalies And Magnetic Storms Observed By China Seismo-Electromagnetic Satellite In August 2018, Jann-Yeng Tiger Liu, Xuhui Shen, Fu-Yuan Chang, Yuh-Ing Chen, Yang-Yi Sun, Chieh‑Hung Chen, Sergey Pulinets, Katsumi Hattori, Dimitar Ouzounov, Valerio Tramutoli, Michel Parrot, Wei-Sheng Chen, Cheng-Yan Liu, Fei Zhang, Dapeng Liu, Xue-Min Zhang, Rui Yan, Qiao Wang
Mathematics, Physics, and Computer Science Faculty Articles and Research
The China Seismo-Electromagnetic Satellite (CSES), with a sun-synchronous orbit at 507 km altitude, was launched on 2 February 2018 to investigate pre-earthquake ionospheric anomalies (PEIAs) and ionospheric space weather. The CSES probes manifest longitudinal features of four-peak plasma density and three plasma depletions in the equatorial/low-latitudes as well as mid-latitude troughs. CSES plasma and the total electron content (TEC) of the global ionosphere map (GIM) are used to study PEIAs associated with a destructive M7.0 earthquake and its followed M6.5 and M6.3/M6.9 earthquakes in Lombok, Indonesia, on 5, 17, and 19 August 2018, respectively, as well as to examine ionospheric …
Cold-Season Precipitation Sensitivity To Microphysical Parameterizations: Hydrologic Evaluations Leveraging Snow Lidar Datasets, W. J. Rudisill, A. N. Flores, H. P. Marshall, E. Siirila-Woodburn, D. R. Feldman, A. M. Rhoades, Z. Xu, A. Morales
Cold-Season Precipitation Sensitivity To Microphysical Parameterizations: Hydrologic Evaluations Leveraging Snow Lidar Datasets, W. J. Rudisill, A. N. Flores, H. P. Marshall, E. Siirila-Woodburn, D. R. Feldman, A. M. Rhoades, Z. Xu, A. Morales
Geosciences Faculty Publications and Presentations
Cloud microphysical processes are an important facet of atmospheric modeling, as they can control the initiation and rates of snowfall. Thus, parameterizations of these processes have important implications for modeling seasonal snow accumulation. We conduct experiments with the Weather Research and Forecasting (WRF V4.3.3) Model using three different microphysics parameterizations, including a sophisticated new scheme (ISHMAEL). Simulations are conducted for two cold seasons (2018 and 2019) centered on the Colorado Rockies’ ∼750-km2 East River watershed. Precipitation efficiencies are quantified using a drying-ratio mass budget approach and point evaluations are performed against three NRCS SNOTEL stations. Precipitation and meteorological outputs …
Investigating Converted Phases In The Midland Basin, Texas, Using Synthetic Seismograms, Julia Rosenblit
Investigating Converted Phases In The Midland Basin, Texas, Using Synthetic Seismograms, Julia Rosenblit
Earth Sciences Theses and Dissertations
Intraplate seismicity in previously aseismic areas within the Permian Basin, Texas, has steadily increased since 2009 (Frohlich et al., 2020). The Midland Basin, the eastern lobe of the Permian, has experienced multiple moderate magnitude earthquakes (M4-6), including the recent 2022 M5.2 Range Hill earthquake. While it is generally accepted that oil and gas development is linked to the seismic activity, and saltwater disposal (SWD) is a significant triggering mechanism in the Midland Basin, understanding the mechanism(s) of shallow (
A Uav Based Cmos Ku-Band Metasurface Fmcw Radar System For Low-Altitude Snowpack Sensing, Adrian Tang, Nacer Chahat, Yangyho Kim, Arhison Bharathan, Gabriel Virbila, Hans-Peter Marshall, Thomas Van Der Weide, Gaurangi Gupta, Raunika Anand, Goutam Chattopadhyay, Mau-Chung Frank Chang
A Uav Based Cmos Ku-Band Metasurface Fmcw Radar System For Low-Altitude Snowpack Sensing, Adrian Tang, Nacer Chahat, Yangyho Kim, Arhison Bharathan, Gabriel Virbila, Hans-Peter Marshall, Thomas Van Der Weide, Gaurangi Gupta, Raunika Anand, Goutam Chattopadhyay, Mau-Chung Frank Chang
Geosciences Faculty Publications and Presentations
This article presents development of a UAV based frequency modulated continuous wave (FMCW) radar system for remotely sensing the water contained within snowpacks. To make the radar system compatible with the payload requirements of small UAV platforms, the radar electronics are implemented with CMOS technology, and the antenna is implemented as an extremely compact and lightweight metasurface (MTS) antenna. This article will discuss how the high absorption losses of snowpacks lead to dynamic range requirements much stricter than FMCW radars used for automotive and other sensing applications, and how these requirements are met through antenna isolation, leakage calibration and exploitation …
Coupling-Informed Data-Driven Scheme For Joint Angle And Frequency Estimation In Uniform Linear Array With Mutual Coupling Present, Yanming Zhang, Wenchao Xu, A. Long Jin, Min Li, Peifeng Ma, Lijun Jiang, Steven Gao
Coupling-Informed Data-Driven Scheme For Joint Angle And Frequency Estimation In Uniform Linear Array With Mutual Coupling Present, Yanming Zhang, Wenchao Xu, A. Long Jin, Min Li, Peifeng Ma, Lijun Jiang, Steven Gao
Electrical and Computer Engineering Faculty Research & Creative Works
This paper proposes a novel coupling-informed data-driven algorithm tailored for the concurrent estimation of frequency and angle within a uniform linear array (ULA), while addressing the complicating influence of mutual coupling. Leveraging the hybrid dynamic mode decomposition (DMD) methodology, termed as averaged DMD, we incorporate moving average techniques to achieve effective denoising. The averaged DMD further decomposes the received signal into eigenvalues and corresponding eigenvectors. The frequency information is derived from the eigenvalues and the corresponding eigenvectors represent the steering vectors of sources. Subsequently, mutual coupling is informed into the calibration of the steering vector for each source. Specifically, the …
A Hybrid Algorithm To Dual Sparse Sampling Measurement In Time-Resolved Electromagnetic Near-Field Scanning, Yanming Zhang, Steven Gao, Lijun Jiang
A Hybrid Algorithm To Dual Sparse Sampling Measurement In Time-Resolved Electromagnetic Near-Field Scanning, Yanming Zhang, Steven Gao, Lijun Jiang
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Time-resolved electromagnetic near-field scanning is vital for antenna measurement and addressing complex electromagnetic interference and compatibility issues. However, the swift acquisition of high-resolution spatiotemporal data remains challenging due to physical constraints, such as moving the probe position and allowing sufficient time for sampling. This paper introduces a novel hybrid approach that combines Kriging for sparse spatial measurement, compressed sensing (CS) for sparse temporal sampling, and dynamic mode decomposition (DMD) for a comprehensive analysis of dual-sparse sampling electromagnetic near-field data. CS optimizes sparse sampling in the time domain, capitalizing on the inherent sparsity within electromagnetic radiated signals, resulting in reliable representation …
A Data-Driven Approach To Time-Domain Electromagnetic Modeling Based On Dynamic Mode Decomposition, Yanming Zhang, Steven Gao, Lijun Jiang
A Data-Driven Approach To Time-Domain Electromagnetic Modeling Based On Dynamic Mode Decomposition, Yanming Zhang, Steven Gao, Lijun Jiang
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
This paper presents a data-driven methodology that utilizes Dynamic Mode Decomposition (DMD) for the time-domain (TD) electromagnetic (EM) modeling of microwave devices. As an unsupervised machine learning technique, DMD leverages a limited set of unlabeled spatio-temporal electromagnetic (EM) data to determine DMD eigenvalues and eigenmodes. Then, the obtained DMD model reconstructs the dynamics as a series of exponential terms based on linear assumptions. The effectiveness of this approach is demonstrated through the TD EM modeling of photonic crystal waveguides. Comparative analysis with the finite-difference time-domain (FDTD) method shows that the DMD model not only achieves precise modeling but also facilitates …
An Unsupervised Learning Framework For Determining The Excitation Coefficients Using Near-Field Antenna Measurements, Yanming Zhang, Peifeng Ma, Steven Gao, Lijun Jiang
An Unsupervised Learning Framework For Determining The Excitation Coefficients Using Near-Field Antenna Measurements, Yanming Zhang, Peifeng Ma, Steven Gao, Lijun Jiang
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
This article presents a novel unsupervised learning framework based on multiscale dynamic mode decomposition for determining the excitation coefficients of antennas using time-domain near-field measurements. The proposed framework integrates temporal multiscale analysis to extract a joint distribution of frequency, damping factors, and spatial modes, enabling precise extraction of excitation frequencies, rising/falling edges, and phases without labeled data. We validate the effectiveness of the proposed approach through two examples involving on-off keying modulation and a phase-shift dipole antenna. It is found that the proposed method performs well in handling nonstationary excitation signals and proves particularly advantageous for calibrating tunable antenna systems. …
Comparative Analysis Of Critical Bond Strength Parameters Of Neat Class G Cement And Fly Ash Enhanced Cement To Steel, C. M. Potter, Andreas Eckert, James A. Jones, Z. Weicheng, M. Meng
Comparative Analysis Of Critical Bond Strength Parameters Of Neat Class G Cement And Fly Ash Enhanced Cement To Steel, C. M. Potter, Andreas Eckert, James A. Jones, Z. Weicheng, M. Meng
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
In subsurface engineering applications, such as wellbore integrity, the interface between cement and steel is integral to expected functionality. The interface between steel and cement is often a structural weak point in many systems, however, the critical parameters for debonding evaluation are poorly understood and derived from outdated experimental procedures. Through experimental debonding tests, this study aims to analyze the tensile bond strength and fracture parameters and their sensitivity to cement composition with a pozzolanic additive (fly ash). Neat Class G cement testing resulted in an average tensile bond strength of 0.223 MPa, an average contact stiffness of 2.94x108 N/m3, …
Extending Active Network Length Versus Catchment Discharge Relations To Temporarily Dry Outlets, Gianluca Botter, James Mcnamara, Nicola Durighetto
Extending Active Network Length Versus Catchment Discharge Relations To Temporarily Dry Outlets, Gianluca Botter, James Mcnamara, Nicola Durighetto
Geosciences Faculty Publications and Presentations
River networks are not steady blue lines drawn in a map, since they continuously change their shape and extent in response to climatic drivers. Therefore, the flowing length of rivers (L) and the corresponding catchment-scale streamflow (Qsur) co-evolve dynamically. This paper analyzes the relationship between the wet channel length and the streamflow of a river basin, formulating a general analytical model that includes the case of temporarily dry outlets. In particular, the framework relaxes the common assumption that when the discharge at the outlet tends to zero the upstream flowing length approaches zero. Different analytical …
Geographically Dependent Thermodynamic And Geochemical Evolution In The Post-Batholith Upper Mantle Beneath The Sierra Nevada: Analysis Of The Blue Knob Xenoliths, Eleanor Ruos
Scripps Senior Theses
Xenoliths entrained in recent (Miocene) volcanics from the Sierra Nevada provide insights into a continuously evolving upper mantle during post-batholith generation periods (early Cenozoic–present). Hypothesized mantle refertilization followed by subsequent delamination of the lithospheric root beneath the Sierra provides a contextual framework for analyzing how the upper mantle responds to such events. This study contributes new geochemical data from the ultramafic xenoliths of Blue Knob, including bulk-rock major and trace element data, thin-section petrography, mineral chemistry and thermobarometry, and oxygen isotopes (delta18O). Blue knob (Eastern Sierra) data are compared to previous works on xenoliths from Chinese Peak and …
The Influence Of Volcano Edifice Resonance On The Seismic Triggering Of Thermal Activity At Active Volcanoes, Morgana M. Wilke
The Influence Of Volcano Edifice Resonance On The Seismic Triggering Of Thermal Activity At Active Volcanoes, Morgana M. Wilke
Dissertations, Master's Theses and Master's Reports
There is an established correlation between large earthquakes and volcanic unrest, however the mechanisms between this connection are not well understood. Relatively small changes in stress within a volcanic system could be enough to initiate a response. One aspect that could serve to amplify small dynamic stress changes is volcanic edifice resonance triggered by surface waves at resonant frequency. In this paper, we investigate the relationship between thermal activity of volcanoes and various minimum thresholds of Love wave amplitudes at resonance caused by teleseismic earthquakes above a 7.0 M. Satellite-derived thermal data from 25 volcanoes are modeled in relation to …
Sh-Wave Seismic-Reflection Efficiency Technique For Investigating The Wolf Island Fault, New Madrid Seismic Zone, Usa, Stephanie Vicroy
Sh-Wave Seismic-Reflection Efficiency Technique For Investigating The Wolf Island Fault, New Madrid Seismic Zone, Usa, Stephanie Vicroy
Theses and Dissertations--Earth and Environmental Sciences
The Reelfoot Fault within the New Madrid seismic zone has displacement at seismogenic depth to which the surface expression has unequal displacement. Previous work identified northeast-oriented transpressional fault strands northeast of a bend in the scarp as evidence for a through-going shear-zone, acting as potential accommodation for the observed strain imbalance. This investigation projected the trend of these faults to their intersection with an industry seismic survey at Wolf Island, Missouri, which exhibits a similarly structured faulted zone. We suggest this structure is the continuation of the through-going shear zone representing a previously unknown 22-km-long Quaternary-active fault that can affect …
High Resolution Sedimentary Investigations Of Extant Lakes In North America, John Dilworth
High Resolution Sedimentary Investigations Of Extant Lakes In North America, John Dilworth
Theses and Dissertations--Earth and Environmental Sciences
Investigation of past lake environments forms the discipline of paleolimnology. Paleolimnological studies seek to evaluate geophysical, geochemical, and ecological proxies and indicators contained within lake sediment archives. Using these potential stores of high-resolution environmental information, questions regarding climate, biological, and geochemical changes experienced by a lake and its watershed can be investigated. This dissertation research utilized lake sediment records from two lakes within North America to study different aspects of environmental change. This dissertation consists of three separate studies presented in three chapters.
Chapter Two presents a retrospective environmental assessment of Jackson Lake, Wyoming to investigate the impacts of dam …
Earthquakes And Seismic Waves: Solutions For Fermi Questions, March 2024, John Adam
Earthquakes And Seismic Waves: Solutions For Fermi Questions, March 2024, John Adam
Mathematics & Statistics Faculty Publications
Solution to Question 1: To estimate h, we take the geometric mean of 1 km and 70 km, or ~8 km, and take ρ ≈ 2500 kg/m³.
Hence, δl ≈ 4 × 0.05 × (2.5 × 10³ kg/m³) × (10 m/s²) × (8 × 10³ m) × (2 × 10⁴ m) × 0.1 ÷ (3 × 1010 kg · m−¹ · s−²) ≈ 1.3 m. (Note that this is not meant to be an estimate of the width of the Icelandic rock fracture in the photograph, though it appears to be of the right order …
Earthquakes And Seismic Waves, John Adam
Earthquakes And Seismic Waves, John Adam
Mathematics & Statistics Faculty Publications
This article discusses earthquakes and seismic waves. It explains that earthquakes occur in the crust or upper mantle, with "shallow" earthquakes happening above a depth of 70 km in the crust. The article also introduces the slider-block model, which is a simple model used to understand earthquake behavior. It provides equations to calculate the displacement and maximum slip velocity of the fault based on various factors. The article then presents two questions related to earthquake calculations. Additionally, it mentions Fermi Questions, which are brief questions with estimation techniques.
An Early Byzantine Ecclesiastical Complex At Ashdod-Yam: Correlating Geophysical Prospection With Excavated Remains, Yaniv Darvasi, Alexander Fantalkin, Paul Brindza, Amotz Agnon
An Early Byzantine Ecclesiastical Complex At Ashdod-Yam: Correlating Geophysical Prospection With Excavated Remains, Yaniv Darvasi, Alexander Fantalkin, Paul Brindza, Amotz Agnon
Physics Faculty Publications
In this study we show the successful deployment of Ground Penetrating Radar (GPR) together with Electrical Resistivity Surveys (ERS) in guiding the archeological excavations at Ashdod-Yam (southern coast of Israel). This approach enabled the precise identification of excavation targets relating to an Early Byzantine ecclesiastical complex located in a residential neighborhood of the modern city of Ashdod. Applied over the course of five years, the combined use of GPR and ERS, interspersed with phases of archeological excavation, not only facilitated an efficient exploration but also ensured the preservation of valuable historical structures. The geophysical data, corroborated by drone images of …
A Tensor-Based Data-Driven Approach For Multidimensional Harmonic Retrieval And Its Application For Mimo Channel Sounding., Yanming Zhang, Wenchao Xu, A. Long Jin, Min Li, Ping Yuan, Lijun Jiang, Steven Gao
A Tensor-Based Data-Driven Approach For Multidimensional Harmonic Retrieval And Its Application For Mimo Channel Sounding., Yanming Zhang, Wenchao Xu, A. Long Jin, Min Li, Ping Yuan, Lijun Jiang, Steven Gao
Electrical and Computer Engineering Faculty Research & Creative Works
In wireless channel sounding, accurately estimating multiple parameters within a multipath signal, such as azimuth, elevation, Doppler shift, and delay, necessitates addressing the challenges posed by the multidimensional harmonic retrieval (MHR) problem. To overcome these complexities, we propose a framework based on high-order dynamic mode decomposition (HODMD) that designed for robustly estimating frequencies of interest from high-dimensional sinusoidal signals, particularly in additive white Gaussian noise conditions. The HODMD approach, a hybrid algorithm amalgamating high-order singular value decomposition (HOSVD) and dynamic mode decomposition (DMD), operates by initially decomposing observed tensorial data into a core tensor and R mode matrices through HOSVD. …
Anomaly Mapping Of Heavy And Light Rare Earth Elements In Central Upper Peninsula Of Michigan Using Geostatistics And Fractal Analysis, Sunday Joseph
Anomaly Mapping Of Heavy And Light Rare Earth Elements In Central Upper Peninsula Of Michigan Using Geostatistics And Fractal Analysis, Sunday Joseph
Dissertations, Master's Theses and Master's Reports
Rare earth elements (REEs) have gained significant global importance due to their critical role in supporting the transition towards reduced carbon emissions through industrial applications. REEs serve as essential raw materials for various critical components in modern infrastructure, defense systems, and technological advancements. Geochemical and geophysical data are pivotal in assessing the potential of REEs. Geochemical data provide direct insights into the elemental composition of rocks and soils, offering valuable information on the potential presence and dispersion of REEs. However, the complex geological processes that influence the distribution of REEs often exhibit intricate spatial patterns that may not be fully …