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Full-Text Articles in Geophysics and Seismology

Effects Of Demineralization Protocols On Hydrogen And Oxygen Isotope Ratios In Fossil Bone Collagen, Linda M. Reynard Nov 2026

Effects Of Demineralization Protocols On Hydrogen And Oxygen Isotope Ratios In Fossil Bone Collagen, Linda M. Reynard

Boise State University Publications and Presentations

The effect of three commonly used preparation protocols on bone collagen δ2H and δ18O values was investigated, using six generally well-preserved faunal bones (cattle, bison, horse) ranging in age from the Holocene to Late Pleistocene. The treatments tested were ethylene diamine tetraacetic acid demineralization without gelatinization and hydrochloric acid demineralization with and without gelatinization. There are significant shifts in δ18O values among preparation methods. No systematic shifts in bone collagen δ2H values were noted among the three treatments, and most offsets were low (< 2–3 ‰) and smaller than typical measurement uncertainties. A few sample/treatment combinations yielded slightly higher inter-treatment δ2H differences (∼ 5–7 ‰). Lower mass fraction of hydrogen in …


Alaska Earthquake Center Quarterly Review October-December 2025, Heather Mcfarland, Beth Grassi, Austin Holland, Nate Murphy, Elisabeth Nadin, Carolyn Parcheta, Michael West Aug 2026

Alaska Earthquake Center Quarterly Review October-December 2025, Heather Mcfarland, Beth Grassi, Austin Holland, Nate Murphy, Elisabeth Nadin, Carolyn Parcheta, Michael West

Alaska Earthquake Center Reports

This series of technical quarterly reports from the Alaska Earthquake Center (AEC) includes detailed summaries and updates on Alaska seismicity, the AEC seismic network and stations, fieldwork, our online presence, public outreach, and lists publications and presentations by AEC staff. Multiple AEC staff members contributed to this report.


Evolution Of Propagator Wakes On The Kolbeinsey Ridge From An Integrated Geophysical Perspective, Ethan Stowell Aug 2026

Evolution Of Propagator Wakes On The Kolbeinsey Ridge From An Integrated Geophysical Perspective, Ethan Stowell

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

Oceanic lithosphere is formed following the extension and rifting of a continent, with new material generated at mid-ocean ridges. While ridges generally spread in the direction of extension, individual spreading centers are offset by perpendicular transform faults that break the ridges into individual segments. Ridge propagation, in which one ridge segment grows at the expense of another’s shortening, has been identified in global investigations as a poorly understood component of axial reorganization. This process leaves propagator wake structures composed of faults and pseudofaults visible as lows in Earth’s gravitational field, and transferred lithosphere with a distorted magnetic signature. This study …


Geothermal Energy In Utah: Massive Potential To Meet Growing Electricity Needs, Emily Labonty, Kendall Becker, Logan Mitchell, Jennifer Bodine, Scott Hotaling Jun 2026

Geothermal Energy In Utah: Massive Potential To Meet Growing Electricity Needs, Emily Labonty, Kendall Becker, Logan Mitchell, Jennifer Bodine, Scott Hotaling

All Current Publications

Including more geothermal energy in Utah's energy mix would help address issues of concern for many Utahns: poor air quality, climate change, and the need to support renewable energy research. Geothermal energy, heat from within the Earth, is a renewable energy source that can provide flexible, baseload electricity––like coal or natural gas––but without the climate-warming and polluting effects. This fact sheet provides information about geothermal energy, generating electricity from geothermal energy, and current geothermal projects in Utah.


Interseismic Creep Along The Enriquillo–Plantain Garden Fault, Haiti, Estimated From Insar, Rishabh Dutta, Jeremy L. Maurer, Yi Chieh Lee Jun 2026

Interseismic Creep Along The Enriquillo–Plantain Garden Fault, Haiti, Estimated From Insar, Rishabh Dutta, Jeremy L. Maurer, Yi Chieh Lee

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Enriquillo–Plantain Garden fault zone (EPGFZ) is a major left-lateral strike-slip fault in southern Haiti hosting several recent destructive earthquakes, including the 2021 MW 7.1 Nippes event with primary thrust-slip. To investigate how strain is accommodated in the vicinity of the 2021 event, we analyzed Sentinel-1 interferometric synthetic aperture radar (InSAR) data from 2017 to 2021 using a PS + DS (persistent + distributed scatterers) InSAR time-series approach to overcome decorrelation in this highly vegetated region. We reveal interseismic creep along the EPGF and adjacent Grand'Anse–Sud border faults, with pure strike-slip mechanism and rates up to 9 mm/yr. We suggest …


A Fiftieth Year Retrospective On The 1976 Mw 7.5 Motagua Earthquake In Guatemala, Grant Clark, Trenton Mcenaney, Jeremy Maurer, Andreas Eckert, Stephen S. Gao, Omar G. Flores, Robin Yani, Tina Niemi, Christoph Grützner, Francisco Gomez, Jonathan Obrist-Farner Jun 2026

A Fiftieth Year Retrospective On The 1976 Mw 7.5 Motagua Earthquake In Guatemala, Grant Clark, Trenton Mcenaney, Jeremy Maurer, Andreas Eckert, Stephen S. Gao, Omar G. Flores, Robin Yani, Tina Niemi, Christoph Grützner, Francisco Gomez, Jonathan Obrist-Farner

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

On 4 February 1976, an Mw > 7:5 earthquake ruptured ∼240 km of the Motagua fault in Guatemala, causing ∼23,000 fatalities. This event provided evidence for the fault's role as a major transform boundary between the North American and Caribbean plates. Field observations, seismological analyses, and postseismic studies helped constrain fundamental aspects of the 1976 earthquake mechanics and the spatial complexity of the rupture. This event opened a window for studies documenting past deformation along this plate boundary across multiple spatial and temporal scales. Five decades of research have established this earthquake as an important event for understanding strike-slip ruptures along …


Monitoring Groundwater Flow At Old Works Using Anisotropy, 3-D Electrical Geophysics, And Dem-Based Terrain Analysis, Yihaun Gao May 2026

Monitoring Groundwater Flow At Old Works Using Anisotropy, 3-D Electrical Geophysics, And Dem-Based Terrain Analysis, Yihaun Gao

Honors Theses

Groundwater flow in shallow heterogeneous environments is often difficult to characterize using a single geophysical method. This study applies an integrated approach combining azimuthal resistivity anisotropy, self-potential (SP) measurements, DEM-derived terrain indices, and three-dimensional electrical resistivity tomography (3-D ERT) to delineate preferential groundwater pathways at the Old Works Golf Course in Anaconda, Montana. Azimuthal anisotropy analysis from eighteen 2-D ERT profiles revealed a dominant directional dependence in electrical conductivity, indicating a structural or sedimentological control on subsurface flow. The anisotropy results indicate a preferred conductivity direction of approximately 200°–210° in azimuth (0° is north), suggesting that groundwater movement is guided …


Changes In Land, Ocean, Atmospheric Parameters Associated With The 2025 Myanmar (Mw 7.7) Earthquake, Feng Jing, Akshansa Chauhan, Ashwani Raju, Ramesh P. Singh Mar 2026

Changes In Land, Ocean, Atmospheric Parameters Associated With The 2025 Myanmar (Mw 7.7) Earthquake, Feng Jing, Akshansa Chauhan, Ashwani Raju, Ramesh P. Singh

Mathematics, Physics, and Computer Science Faculty Articles and Research

Multiple parameters associated with the land, atmosphere, and ocean were analyzed to study short-term and immediate pre-earthquake changes associated with the 28 March 2025 Myanmar earthquake (Mw 7.7). Anomalous clear-sky outgoing longwave radiation (ClrOLR) and trace gases (CH₄, CO, and O₃) were detected within two months prior to the mainshock. Vertical changes at different pressure levels suggest a possible underground source. High-temporal-resolution observations of the infrared brightness temperature and surface air pressure revealed short-lived fluctuations shortly before the earthquake, which may reflect localized stress adjustments and surface latent heat flux release during the final stage of earthquake preparation. In the …


The Effects Of A Microplate On Plume-Ridge Interactions: Constraints From Comparing Easter And Juan Fernandez Microplates In The Eastern Pacific Ocean, Katherine Ames, Jennifer Georgen Jan 2026

The Effects Of A Microplate On Plume-Ridge Interactions: Constraints From Comparing Easter And Juan Fernandez Microplates In The Eastern Pacific Ocean, Katherine Ames, Jennifer Georgen

OES Faculty Publications

This study investigates the nature of plume-ridge interactions near a tectonic microplate using mantle Bouguer anomaly (MBA) gravity calculations. The focus of this investigation is a comparison of the Easter and Juan Fernandez microplates, which are located in the eastern Pacific Ocean along the Pacific, Nazca, and Antarctic plate boundaries. The microplates have several similar characteristics, including general size, time of formation, and clockwise rotation within the larger bounding mid-ocean ridge systems. Unlike the Juan Fernandez microplate, however, the Easter microplate is located near a mantle plume (Easter/Salas y Gomez). Previously published geochemical data suggest that material from this plume …


Soil Characterization With Proximal Geophysics, Sophia M. Becker Dec 2025

Soil Characterization With Proximal Geophysics, Sophia M. Becker

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

High quality soil data is crucial for addressing numerous threats to human well-being such as water scarcity, food insecurity, and intensified natural disasters. True soil property values are determined by analyzing soil samples in a laboratory, but soil sampling is often expensive and time-consuming. Some in-field point sensors and remote sensing products are available to measure soil properties, but they have inherent limitations in measurement extent and resolution. Geophysical methods can fill the measurement scale gap between point measurements and remote sensing products, but various research questions remain open. This dissertation aims to advance understanding of geophysics-derived soil property measurements …


Modeling The Greenland-Iceland-Faroe Ridge Using Integrated Geophysical Analysis, Zachary Clowdus Dec 2025

Modeling The Greenland-Iceland-Faroe Ridge Using Integrated Geophysical Analysis, Zachary Clowdus

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

The Greenland-Iceland-Faroe Ridge (GIFR) is an area of significant geologic interest with anomalously thick crust related to enhanced melt generation from the interaction between the Mid-Atlantic Ridge and the Iceland hotspot. To the northeast of Iceland lies the Jan Mayen Microcontinent (JMMC), which is a continental fragment separated from Greenland during the opening of the Northern Atlantic. The overall extent of the JMMC, especially its southern boundary, remains poorly constrained. The crust beneath the GIFR is believed to be primarily of oceanic affinity. However, a recent discovery of felsic lavas in Iceland led to an alternative hypothesis that implies the …


Advancements In Sinkhole Remediation: Field Data-Driven Sinkhole Grout Volume Prediction Model Via Machine Learning-Based Regression Analysis, Bubryur Kim, Yuvaraj Natarajan, K. R. Sri Preethaa, V. Danushkumar, Ryan Shamet, Jiannan Chen, Rui Xie, Timothy Copeland, Boo Hyun Nam, Jinwoo An Dec 2025

Advancements In Sinkhole Remediation: Field Data-Driven Sinkhole Grout Volume Prediction Model Via Machine Learning-Based Regression Analysis, Bubryur Kim, Yuvaraj Natarajan, K. R. Sri Preethaa, V. Danushkumar, Ryan Shamet, Jiannan Chen, Rui Xie, Timothy Copeland, Boo Hyun Nam, Jinwoo An

Civil Engineering Faculty Publications

Sinkhole formation poses a significant geohazard in karst regions, where unpredictable subsurface erosion often necessitates costly grouting for stabilization. Accurate estimation of grout volume remains a persistent challenge due to spatial variability, site-specific conditions, and the limitations of traditional empirical methods. This study introduces a novel machine learning-based regression model for grout volume prediction that integrates cone penetration test (CPT)-derived Sinkhole Resistance Ratio (SRR) values, spatial correlations between CPT and grouting points (GPs), and field-recorded grout volumes from six sinkhole sites in Florida. Three data transformation methods, the Proximal Allocation Method (PAM), the Equitable Distribution Method (EDM), and the Threshold-based …


Characterization Of River Discharge And Interaction With Shallow Groundwater Aquifers Along The Wabash River Using Seismological Methods, Jessica M. Cyr, Xiaotao Yang, Marty D. Frisbee Nov 2025

Characterization Of River Discharge And Interaction With Shallow Groundwater Aquifers Along The Wabash River Using Seismological Methods, Jessica M. Cyr, Xiaotao Yang, Marty D. Frisbee

Discovery Undergraduate Interdisciplinary Research Internship

The interaction between shallow aquifers and local rivers in the West Lafayette, Indiana area remains poorly understood. While surface water levels in the Wabash River and its tributaries are monitored at several USGS stream gauges, groundwater fluctuations are less well documented. Methods using seismic recordings, sensitive to subtle ground vibrations and subsurface structure, provide an alternative to characterize groundwater levels and river discharge. This project analyzes the temporal variations of ambient noise seismic data, examining the relationship to USGS river discharge, precipitation records, and other environmental factors. We currently focus on 1) changes in maximum amplitudes and peak frequencies within …


Vulnerability Of Blue Carbon In Coastal Freshwater Ecosystems To Sea-Level Rise, Suvrajit Ghosh, Jonathan Obrist-Farner, Jeffery R. Stone, Marta Wojewodka-Przybyt, Ryan Smith, Mark Brenner, Jason H. Curtis, Susan R. H. Zimmerman, Alex Correa-Metrio, Paula Gabriela Echeverrio Galinda, Madeline J. Brosky, Liseth Perez Oct 2025

Vulnerability Of Blue Carbon In Coastal Freshwater Ecosystems To Sea-Level Rise, Suvrajit Ghosh, Jonathan Obrist-Farner, Jeffery R. Stone, Marta Wojewodka-Przybyt, Ryan Smith, Mark Brenner, Jason H. Curtis, Susan R. H. Zimmerman, Alex Correa-Metrio, Paula Gabriela Echeverrio Galinda, Madeline J. Brosky, Liseth Perez

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Coastal freshwater ecosystems are economically and ecologically important and provide multiple environmental services worldwide. They sequester carbon at rates ten times faster, and store five times more carbon per unit area than do mature tropical forests. Vulnerability of these carbon sinks to marine inundation, however, is expected to increase in response to global sea-level rise (GSLR). To better understand the implications of future GSLR, we investigated the geochemical and biological consequences of episodic Holocene marine incursions into Lake Izabal, a large coastal freshwater ecosystem on the Caribbean coast of Central America. About 8300 cal yr BP, marine incursion transformed Lake …


Evaluation Of Towed Tem Potential For Rapid Characterization Of Levee Foundations, Kolawole Arowoogun, Katherine Grote, Jeremy Maurer Oct 2025

Evaluation Of Towed Tem Potential For Rapid Characterization Of Levee Foundations, Kolawole Arowoogun, Katherine Grote, Jeremy Maurer

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Assessing the geologic conditions of levee foundation soils is a challenging task owing to the extensive length of most levees and the heterogeneity of many alluvial deposits. Traditional investigation techniques (such as boring and cone penetrometer testing [CPT]) are expensive, invasive, and provide spatially-limited information. As a result, they are restricted to pre-identified problematic zones in the levee. To overcome these challenges, geophysical instruments capable of better spatial coverage are proposed for rapid geoelectrical characterization of levees. In this study, we presented a field-based application of the towed time-domain electromagnetic method (tTEM) system in characterizing the subsurface geology adjacent to …


Paleoseismic Evidence Of Directivity For The 1976 Mw 7.5 Motagua Earthquake, Guatemala, Jonathan Obrist-Farner, Jeremy Maurer, Derek Gibson, Trenton Mcenaney, Andreas Eckert, William F. Kenney, Jeffrey Beeson, Nigel Wattrus, Quin Stangeland, Fatima Reyes Sep 2025

Paleoseismic Evidence Of Directivity For The 1976 Mw 7.5 Motagua Earthquake, Guatemala, Jonathan Obrist-Farner, Jeremy Maurer, Derek Gibson, Trenton Mcenaney, Andreas Eckert, William F. Kenney, Jeffrey Beeson, Nigel Wattrus, Quin Stangeland, Fatima Reyes

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

On 4 February 1976, a Mw 7.5 earthquake along the Motagua fault, Guatemala, ruptured ∼230 km of the North American and Caribbean plate boundary. Today, the plate boundary remains poorly monitored, and the 1976 earthquake is still not fully understood. Here, we present seismic reflection profiles and radiometrically dated sediment core data from six lakes around the Motagua fault, together with reports of destruction and a quasi-dynamic rupture model, which show that the 1976 earthquake experienced strong directivity that impacted the distribution of shaking. The earthquake left behind a detailed record of event deposits (EDs) in five of the six …


Comparative Analysis Of Different Magnetic Anomaly Datasets Using Navigation Performance With Flight Test Data, Aaron P. Nielsen, Brandon M. Blakely, Patrick Duff Sep 2025

Comparative Analysis Of Different Magnetic Anomaly Datasets Using Navigation Performance With Flight Test Data, Aaron P. Nielsen, Brandon M. Blakely, Patrick Duff

Faculty Publications

Magnetic Anomaly Navigation (MagNav) is a map-based method of navigation which relies on accurately obtaining the anomaly field to a high level of precision to achieve good navigation results. This requires utilizing high quality sensors, accurately modeling disturbance fields from the aircraft & other sources, and creating high-fidelity maps. Aeromagnetic survey data or marine track survey data must be processed into a product that can be used as a reference for a magnetic navigator and a variety of techniques can be utilized for this processing. The data collection for different survey types reflects choices typically made to study the underlying …


Mantle Flow And Fault Zone Related Seismic Anisotropy Revealed By A Dense Linear Broadband Array In Southeast Tibet, Jing Wu, Yinshuang Ai, Stephen S. Gao, Peixi Huang, Fansheng Kong, Deke Xu, Jianguo Song, Xinyu Gao, Mengyi Wei, Long Li, Jien Zhang, Yanbin Zhang, Yingying Zhang Aug 2025

Mantle Flow And Fault Zone Related Seismic Anisotropy Revealed By A Dense Linear Broadband Array In Southeast Tibet, Jing Wu, Yinshuang Ai, Stephen S. Gao, Peixi Huang, Fansheng Kong, Deke Xu, Jianguo Song, Xinyu Gao, Mengyi Wei, Long Li, Jien Zhang, Yanbin Zhang, Yingying Zhang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Southeast Tibet, a key region for the southeastward extrusion of the Tibetan Plateau, remains debated in terms of its tectonic deformation in response to the ongoing collision between the Indian and Eurasian plates. In this study, we applied shear-wave splitting analysis of core-refracted phases recorded by a newly deployed dense seismic array and six permanent stations to delineate crustal and mantle deformation processes. The observed fast polarization directions are predominantly aligned NNW–SSE, while the splitting delay times vary across four sub-blocks. The anisotropy pattern suggests a dominantly asthenospheric origin, consistent with southeastward-directed mantle flow associated with the extrusion of the …


New Precipitation Is Scarce In Deep Soils: Findings From 47 Forest Plots Spanning Switzerland, Emily I. Burt, Scott T. Allen, Sabine Braun, Simon Tresch, James W. Kirchner, Gregory R. Goldsmith Aug 2025

New Precipitation Is Scarce In Deep Soils: Findings From 47 Forest Plots Spanning Switzerland, Emily I. Burt, Scott T. Allen, Sabine Braun, Simon Tresch, James W. Kirchner, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

As precipitation infiltrates into soils, it can recharge them, displace previously stored waters, or bypass already-filled pores. Using 3,697 δ2H and δ18O measurements of water collected nearly monthly over >3 years in 47 forest plots across Switzerland, we present a systematic investigation of the controls on mobile soil water transport. We quantified the lags and damping of water as it percolates downward using young water fraction analysis (Fyw), and the fractions of soil water composed by precipitation that fell within the previous month (new water fractions, Fnew). The Fnew of water sampled in surface soils ranged …


Receiver Function Imaging Of The Mantle Transition Zone Beneath The East Sayan Mountains And Adjacent Area In Central Asia: Implications For Lithospheric Drip And Intraplate Cenozoic Volcanism, Yangyang Liao, Kelly H. Liu, Stephen S. Gao Aug 2025

Receiver Function Imaging Of The Mantle Transition Zone Beneath The East Sayan Mountains And Adjacent Area In Central Asia: Implications For Lithospheric Drip And Intraplate Cenozoic Volcanism, Yangyang Liao, Kelly H. Liu, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

To provide constraints on the formation mechanisms of intracontinental volcanisms and intriguing lithospheric thickness variations in the East Sayan Mountains and surrounding areas, we stack P-to-s receiver functions to image the 410-km and 660-km discontinuities. Mantle transition zone (MTZ) thickening observed in a continuous area is attributable to ancient slab remnants, and Cenozoic volcanisms in the peripheral area can be explained by slab dehydration. The thinning of the MTZ in the Tuva-Mongolian Massif can be explained by mantle upwelling branches induced by slab subduction. Our results reveal an approximately circular area in the MTZ that is significantly thicker than usual, …


Mantle Flow And Crustal Deformation Revealed By Seismic Anisotropy In The Subduction Zone Beneath Myanmar, Enbo Fan, Mingming Jiang, Yinshuang Ai, Stephen S. Gao, Kelly H. Liu, Yumei He, Yiming Bai, Guangbing Hou, Yuan Ling, Chit Thet Mon, Myo Thant, Kyaing Sein Aug 2025

Mantle Flow And Crustal Deformation Revealed By Seismic Anisotropy In The Subduction Zone Beneath Myanmar, Enbo Fan, Mingming Jiang, Yinshuang Ai, Stephen S. Gao, Kelly H. Liu, Yumei He, Yiming Bai, Guangbing Hou, Yuan Ling, Chit Thet Mon, Myo Thant, Kyaing Sein

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The oblique convergence of the Indian and Eurasian plates drives significant deformation in the crust and mantle beneath Myanmar. However, the crustal deformation in the Indo-Burman Ranges (IBR) and mantle flow beneath Myanmar and adjacent areas remain unclear due to limited studies. We utilized data from the newly deployed second phase of the China-Myanmar Geophysical Survey of the Myanmar Orogen array to perform shear wave splitting analysis of PKS, SKKS, and SKS (XKS) phases. Our results, together with previous findings, provide new insights into mantle flow and crustal deformation across central Myanmar. In the IBR, we observed a transition from …


Mapping Sedimentary And Crustal Thicknesses In The Northern Atlantic Ocean From Public Domain Geophysical Data, Hermione Lofton Aug 2025

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

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

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


Deformation And Earthquake Potential On The North America - Caribbean - Cocos Triple Junction In Guatemala, Jeremy Maurer, Andreas Eckert, Qiaoqi Sun, Jonathan Obrist-Farner Jul 2025

Deformation And Earthquake Potential On The North America - Caribbean - Cocos Triple Junction In Guatemala, Jeremy Maurer, Andreas Eckert, Qiaoqi Sun, Jonathan Obrist-Farner

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The triple junction between the Cocos (CO), North American (NA), and Caribbean (CA) tectonic plates in Guatemala is a region of high seismic risk and includes many large faults and historic earthquakes. Previous analyses of the tectonic system have been overly simplified, resulting in discrepancies between geologically derived and geodetic models of fault slip rate. This study leverages available geodetic, seismic, and geologic data to develop new strain rate maps and faulting models for the region. We find that locking on the regional faults matches historic reports of large earthquakes and that multiple minor fault segments are active and accommodate …


Leveraging Weekly Snow Cover Time Series For Improved Glacier Monitoring And Modeling, Rainey Aberle, Ellyn M. Enderlin, David R. Rounce, Shad O'Neel, Brandon Tober, Alexandra Friel Jul 2025

Leveraging Weekly Snow Cover Time Series For Improved Glacier Monitoring And Modeling, Rainey Aberle, Ellyn M. Enderlin, David R. Rounce, Shad O'Neel, Brandon Tober, Alexandra Friel

Boise State University Publications and Presentations

Seasonal snow and ice melt strongly influence glacier mass balance, yet sparse sub-annual observations limit our understanding of seasonal dynamics. Here we construct and analyze weekly snow cover time series for 200 glaciers across western North America from 2013 to 2023 using an automated image processing pipeline. Snow cover varied widely across the region: snow minima timing varied with latitude — from August from 62 to 64N to October from 48 to 50N—and accumulation area ratios ranged from near-zero to 0.92 (median of 0.52). A comparison of snowlines from observations and the PyGEM glacier mass balance model revealed seasonally evolving …


Retraction: A Database Of Teleseismic Shear-Wave Splitting Measurements For The Ordos Block And Adjacent Areas(Seismological Research Letters (2022), 93, 5, (2731–2739), 10.1785/0220210310), Lin Liu, Stephen S. Gao, Kelly H. Liu, Tu Xue, Yan Jia, Sanzhong Li Jul 2025

Retraction: A Database Of Teleseismic Shear-Wave Splitting Measurements For The Ordos Block And Adjacent Areas(Seismological Research Letters (2022), 93, 5, (2731–2739), 10.1785/0220210310), Lin Liu, Stephen S. Gao, Kelly H. Liu, Tu Xue, Yan Jia, Sanzhong Li

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

An earlier version of this article (Liu et al., 2022) included private data from the Himalayan-III program which should not have been made public. The authors acknowledge and regret their negligence during the selection of the measurements. The impacted data represent only 2.7% of the total data published in this article, and after review, the authors and the editors agree that this unintentional error has no bearing on the work's scientific conclusions. Therefore, we are retracting the impacted data and have made corrections to remove any Himalayan-III program data from the article's text, figures, and supplemental tables.


Deciphering A Quantitative Relationship Between Rifting And Crustal Melt Fraction: Insights From The Incipient Okavango Rift Zone, Tuo Wang, Ling Chen, Stephen S. Gao, Kelly H. Liu Jun 2025

Deciphering A Quantitative Relationship Between Rifting And Crustal Melt Fraction: Insights From The Incipient Okavango Rift Zone, Tuo Wang, Ling Chen, Stephen S. Gao, Kelly H. Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Rifting and magmatism are fundamental geological processes in the evolution of the lithosphere; however, quantitative investigations of their relationship are rare. The Okavango Rift Zone (ORZ) is in the early stages of rifting and magmatic activity and thus is an ideal locale to study this relationship. We examine the relationship using two primary crustal structure parameters: crustal thickness and average Vp/Vs ratio obtained from receiver functions. Our large Vp/Vs estimates indicate the existence of melts within the crust of the ORZ. Comparing our results with those of other continental rifts, we identify a quantitative relationship between rifting and crustal melt …


Comprehensive Global Data Set Of Uniformly Processed Shear-Wave Splitting Measurements, Jonathan Wolf, Thorsten W. Becker, Edward Garnero, Kelly H. Liu, John D. West May 2025

Comprehensive Global Data Set Of Uniformly Processed Shear-Wave Splitting Measurements, Jonathan Wolf, Thorsten W. Becker, Edward Garnero, Kelly H. Liu, John D. West

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Seismic anisotropy can inform us about convective flow in the mantle. Shear waves traveling through azimuthally anisotropic regions split into fast and slow pulses, and measuring the resulting shear-wave splitting provides some of the most direct insights into Earth's interior dynamics. Shear-wave splitting is a constraint for path-averaged azimuthal anisotropy and is often studied regionally. Global compilations of these measurements also exist. Such compilations include measurements obtained using different data processing methodologies (e.g., filtering), which do not necessarily yield identical results, and reproducing a number of studies can be challenging given that not all provide the required information, for example, …


Evidence For Distal Bolide Impact And Tsunami Deposits In The Upper Atlantic Coastal Plain Of Moore County (North Carolina, Usa) Generated By The Eocene Chesapeake Bay Bolide Impact, G. Robert Ganis, Ralph H. Willoughby, David J. Cicimurri, G. Richard Whittecar, Steven J. Hageman May 2025

Evidence For Distal Bolide Impact And Tsunami Deposits In The Upper Atlantic Coastal Plain Of Moore County (North Carolina, Usa) Generated By The Eocene Chesapeake Bay Bolide Impact, G. Robert Ganis, Ralph H. Willoughby, David J. Cicimurri, G. Richard Whittecar, Steven J. Hageman

OES Faculty Publications

Beds interpreted as Eocene bolide-generated impact and tsunami deposits occur at Paint Hill in the Upper Atlantic Coastal Plain of Moore County, North Carolina, USA. These strata, herein named the Mount Helicon Formation, consist of four distinct beds comprising about one meter of total section. Bed 1 (the basal bed) is approximately 43 cm thick and consists of sandy carbonaceous clay with carbon glass and rock fragments and contains 14-18 parts per billion (ppb) iridium (interpreted as bolide impact ejecta). Bed 2 is approximately 9 cm thick and consists of non-cohesive silt-size particles and loosely bound sand-size accretionary lapilli-like masses …


Laboratory Earthquakes In Heterogeneous, Meter-Scale Faults: Collaborative Research With Utah State University, And University Of Texas At Austin, Srisharan Shreedharan May 2025

Laboratory Earthquakes In Heterogeneous, Meter-Scale Faults: Collaborative Research With Utah State University, And University Of Texas At Austin, Srisharan Shreedharan

Funded Research Records

No abstract provided.


Integrated Geophysical Modeling Of Newly Identified Pseudofaults Within Southern Cascadia Subduction Zone, Morgan R. Madsen Mar 2025

Integrated Geophysical Modeling Of Newly Identified Pseudofaults Within Southern Cascadia Subduction Zone, Morgan R. Madsen

Honors Program: Senior Projects (Public)

The Cascadia Subduction Zone, located off the western coast of North America, has a long history of seismic activity, causing various geohazards such as megathrust earthquakes and tsunamis for the coastal population (Goldfinger et al., 2000; Tréhu et al., 2022). It is necessary to identify areas of greater risk, as seismic hazards will continue to affect the area due to ongoing subduction of the oceanic Juan de Fuca plate beneath the North American continent. Heavily fractured, weakened zones of oceanic crust, known as propagator wakes and pseudofaults, have been shown to correlate with greater seismicity (Ashraf and Filina, 2023a). Propagator …