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Tracking Induced Seismicity In The Fort Worth Basin, Texas And Northern Oklahoma Using Local And Large-N Style Arrays, Louis Quinones 2021 Southern Methodist University

Tracking Induced Seismicity In The Fort Worth Basin, Texas And Northern Oklahoma Using Local And Large-N Style Arrays, Louis Quinones

Earth Sciences Theses and Dissertations

Since 2008, earthquake sequences within the Fort Worth Basin (FWB), north Texas, have been linked to wastewater disposal activities related to unconventional shale gas production. Here, I present my work analyzing and cataloging a complete record of the seismicity occurring within the basin over a period of more than a decade (2008-2020). Analysis of the catalog reveals that the earthquakes generally occur within the Precambrian basement along steeply dipping normal faults, and while overall seismicity rates have decreased since 2016, new faults have become active. I observe strong spatial and temporal correlations between the earthquake locations and wastewater disposal well ...


Prevention And Preparedness Of The Messina-Reggio Calabria Strait: An Earthquake Forecasting And Didactic Project, Francesco Di Stefano, Gioacchino Giampaolo Giuliani, Dimitar Ouzounov, Daniele Cataldi, Cristiano Fidani, Angelo D'Errico, Giulia Fioravanti 2021 Foundation “G. Giuliani ONLUS”

Prevention And Preparedness Of The Messina-Reggio Calabria Strait: An Earthquake Forecasting And Didactic Project, Francesco Di Stefano, Gioacchino Giampaolo Giuliani, Dimitar Ouzounov, Daniele Cataldi, Cristiano Fidani, Angelo D'Errico, Giulia Fioravanti

Mathematics, Physics, and Computer Science Faculty Articles and Research

This contribution is addressed to an introductive university course on the correlation existing between radon emission and earthquakes processes held following a flipped-class approach where students receive didactic materials prior to face-to-face lessons. This research was initially started to investigate the real correlation between Radon emission from the Earth and the occurrence of strong earthquakes by using measurements of hourly Radon flow variation. During quiet seismogenic conditions, we observe an unvarying level of Radon emission in the air. Before a strong earthquake, substantial variations of Radon (222Rn) concentration have been observed in the air, probably because of the increase ...


Stochastic Source Modelling And Tsunami Analysis Of The 2012 Mw 7.8 Haida Gwaii Earthquake, Karina Martinez Alcala 2021 The University of Western Ontario

Stochastic Source Modelling And Tsunami Analysis Of The 2012 Mw 7.8 Haida Gwaii Earthquake, Karina Martinez Alcala

Electronic Thesis and Dissertation Repository

The Mw 7.8 2012 Haida Gwaii Earthquake triggered a tsunami that highlighted the importance of tsunami hazard assessment on Canada’s Pacific coast. Stochastic source modelling serves as a valuable method to assess future tsunami hazard and has not been performed for this region. The source models characterize the uncertainty of earthquake ruptures by considering variability in fault geometry and slip heterogeneity, which, in turn, allows the consideration of a wide range of tsunami scenarios in the Haida Gwaii region. The model predictions are constrained by observational data and past source inversion studies. One hundred twenty-eight stochastic tsunami scenarios ...


A Transformer-Based Classification System For Volcanic Seismic Signals, Cristian Bravo Roman, Cindy Mora Stock, Alexander James Hemming 2021 Western University

A Transformer-Based Classification System For Volcanic Seismic Signals, Cristian Bravo Roman, Cindy Mora Stock, Alexander James Hemming

Undergraduate Student Research Internships Conference

Volcanic seismic signals are a key element in volcano monitoring to assess the state of unrest and a possible eruption style and timing. Different sources such as brittle fracture (volcano-tectonic - VT) or fluid movement (long period - LP) generate signals with distinct characteristics in frequency content and shape, but site effects such as attenuation or background noise make their determination difficult to the untrained eye. In cases of unrest or an eminent eruption, the amount of data would require a fast and reliable source of pre-classification to classify and catalogue to aid in the job usually done by a human.

To ...


Stratigraphic Evidence Of Two Historical Tsunamis On The Semi-Arid Coast Of North-Central Chile, Jessica M. DePaolis, Tina Dura, Breanyn MacInnes, Lisa L. Ely, Marco Cisternas, Matías Carvajal, Hui Tang, Hermann M. Fritz, Cyntia Mizobe, Robert L. Wesson, Gino Figueroa, Nicole Brennan, Benjamin P. Horton, Jessica E. Pilarczyk, D. Reide Corbett, Benjamin C. Gill, Robert Weiss 2021 Virginia Polytechnic Institute and State University

Stratigraphic Evidence Of Two Historical Tsunamis On The Semi-Arid Coast Of North-Central Chile, Jessica M. Depaolis, Tina Dura, Breanyn Macinnes, Lisa L. Ely, Marco Cisternas, Matías Carvajal, Hui Tang, Hermann M. Fritz, Cyntia Mizobe, Robert L. Wesson, Gino Figueroa, Nicole Brennan, Benjamin P. Horton, Jessica E. Pilarczyk, D. Reide Corbett, Benjamin C. Gill, Robert Weiss

Geological Sciences Faculty Scholarship

On September 16, 2015, a Mw 8.3 earthquake struck the north-central Chile coast, triggering a tsunami observed along 500 km of coastline, between Huasco (28.5°S) and San Antonio (33.5°S). This tsunami provided a unique opportunity to examine the nature of tsunami deposits in a semi-arid, siliciclastic environment where stratigraphic and sedimentological records of past tsunamis are difficult to distinguish. To improve our ability to identify such evidence, we targeted one of the few low-energy, organic-rich depositional environments in north-central Chile: Pachingo marsh in Tongoy Bay (30.3°S).

We found sedimentary evidence of the ...


Analysis Of Gravity For The Crustal Structure Of Nepal Himalaya, Kapil Prasad Phuyal 2021 Missouri State University

Analysis Of Gravity For The Crustal Structure Of Nepal Himalaya, Kapil Prasad Phuyal

MSU Graduate Theses

Nepal Himalaya is situated in the central portion of the seismically active Himalayan Orogenic Belt, which is geologically segmented by four major mega fault structures: Main Frontal Thrust (MFT), Main Boundary Thrust (MBT), Main Central Thrust (MCT), and the South Tibetan Detachment System (STDS). The MFT, MBT, and MCT are part of the basal decollement Main Himalayan Thrust (MHT) which accommodates the convergence between the Indian and Eurasian Plate. The 2015 Gorkha Earthquake occurred within the MHT system, MHT system itself had been seismically locked since the 1934 Nepal-Bihar Earthquake, complicating the geometry depth of MHT. Available land and airborne ...


Kinematics Of The Exceptionally-Short Surge Cycles Of Sít’ Kusá (Turner Glacier), Alaska, From 1983 To 2013, Andrew Nolan, William Kochtitzky, Ellyn M. Enderlin, Robert McNabb, Karl J. Kreutz 2021 University of Maine

Kinematics Of The Exceptionally-Short Surge Cycles Of Sít’ Kusá (Turner Glacier), Alaska, From 1983 To 2013, Andrew Nolan, William Kochtitzky, Ellyn M. Enderlin, Robert Mcnabb, Karl J. Kreutz

Geosciences Faculty Publications and Presentations

Glacier surges are periodic episodes of mass redistribution characterized by dramatic increases in ice flow velocity and, sometimes, terminus advance. We use optical satellite imagery to document five previously unexamined surge events of Sít’ Kusá (Turner Glacier) in the St. Elias Mountains of Alaska from 1983 to 2013. Surge events had an average recurrence interval of ~5 years, making it the shortest known regular recurrence interval in the world. Surge events appear to initiate in the winter, with speeds reaching up to ~25 m d−1. The surges propagate down-glacier over ~2 years, resulting in maximum thinning of ~100 m ...


Diatoms Of The Intertidal Environments Of Willapa Bay, Washington, Usa As A Sea-Level Indicator, Isabel Hong, Benjamin P. Horton, Andrea D. Hawkes, Robert J. O.Donnell III, Jason S. Padgett, Tina Dura, Simon E. Engelhart 2021 Central Washington University

Diatoms Of The Intertidal Environments Of Willapa Bay, Washington, Usa As A Sea-Level Indicator, Isabel Hong, Benjamin P. Horton, Andrea D. Hawkes, Robert J. O.Donnell Iii, Jason S. Padgett, Tina Dura, Simon E. Engelhart

Geological Sciences Faculty Scholarship

An understanding of the modern relationship between diatom species and elevation is a prerequisite for using fossil diatoms to reconstruct relative sea level (RSL). We described modern diatom distributions from seven transects covering unvegetated subtidal environments to forested uplands from four tidal wetland sites (Smith Creek, Bone River, Niawiakum River, and Naselle River) of Willapa Bay, Washington, USA. We compared our diatom dataset (320 species from 104 samples) to a series of environmental variables (elevation, grain-size, total organic carbon (TOCSOM), and porewater salinity) using hierarchical clustering and ordination. While no single variable consistently explains variations in diatom assemblages at ...


Fragmentation Theory Reveals Processes Controlling Iceberg Size Distributions, Jan Åström, Sue Cook, Ellyn M. Enderlin, David A. Sutherland, Aleksandra Mazur, Neil Glasser 2021 CSC – IT Center for Science

Fragmentation Theory Reveals Processes Controlling Iceberg Size Distributions, Jan Åström, Sue Cook, Ellyn M. Enderlin, David A. Sutherland, Aleksandra Mazur, Neil Glasser

Geosciences Faculty Publications and Presentations

Iceberg calving strongly controls glacier mass loss, but the fracture processes leading to iceberg formation are poorly understood due to the stochastic nature of calving. The size distributions of icebergs produced during the calving process can yield information on the processes driving calving and also affect the timing, magnitude, and spatial distribution of ocean fresh water fluxes near glaciers and ice sheets. In this study, we apply fragmentation theory to describe key calving behaviours, based on observational and modelling data from Greenland and Antarctica. In both regions, iceberg calving is dominated by elastic-brittle fracture processes, where distributions contain both exponential ...


Timescales Of Impact Melt Sheet Crystallization And The Precise Age Of The Morokweng Impact Structure, South Africa, Gavin G. Kenny, Claire O. Harrigan, Mark D. Schmitz, James L. Crowley, Corey J. Wall 2021 Boise State University

Timescales Of Impact Melt Sheet Crystallization And The Precise Age Of The Morokweng Impact Structure, South Africa, Gavin G. Kenny, Claire O. Harrigan, Mark D. Schmitz, James L. Crowley, Corey J. Wall

Geosciences Faculty Publications and Presentations

Impact cratering was a fundamental geological process in the early Solar System and, thus, constraining the timescales over which large impact structures cool is critical to understanding the thermal evolution and habitability of early planetary crusts. Additionally, impacts can induce mass extinctions and establishing the precise timing of the largest impacts on Earth can shed light on their role in such events. Here we report a high-precision zircon U–Pb geochronology study of the Morokweng impact structure, South Africa, which appears to have a maximum present-day diameter of ∼80 km. Our work provides (i) constraints on the cooling of large ...


Integrated Geophysical Analysis Over Bathymetrists Seamounts And The Sierra Leone Rise, Alexa Fernandez 2021 University of Nebraska-Lincoln

Integrated Geophysical Analysis Over Bathymetrists Seamounts And The Sierra Leone Rise, Alexa Fernandez

UCARE Research Products

The Bathymetrists Seamounts (BSM) are located northeast of the Sierra Leone Rise in the Atlantic Ocean. The northern seamounts have a southwest to northeast trend which is contrary to the current eastward motion of the African tectonic plate where they reside. The geological history and crustal structures of these features are poorly understood. The goal of this study is to integrate multiple geophysical data to better understand the crustal architecture and tectonic history of the BSM.

The seismic refraction study from Jones et al. (2015) was used as the baseline for isostatic modeling. This dataset suggested the presence of magmatic ...


Developing A Database Of Seismic Data Over The Cascadia Subduction Zone, Khawlh Al Farsi 2021 University of Nebraska-Lincoln

Developing A Database Of Seismic Data Over The Cascadia Subduction Zone, Khawlh Al Farsi

Dissertations & Theses in Earth and Atmospheric Sciences

An inevitable megathrust earthquake is expected in the Cascadia subduction zone that will affect the population of the coast of southwestern British Columbia and the northwest of the United States. In this active tectonic margin, the Juan de Fuca oceanic plate is subducting beneath the North American continental plate, causing unevenly distributed seismic activity. The major goal of this geophysical research project is to study the tectonic structures of the Cascadia subduction zone in order to comprehend the geology of the region and investigate the seismic hazards. The primary objective of this project is to develop a geophysical database of ...


Seismic Imaging In Crystalline Terrains Of The Superior Province, Canada, Brian Villamizar 2021 The University of Western Ontario

Seismic Imaging In Crystalline Terrains Of The Superior Province, Canada, Brian Villamizar

Electronic Thesis and Dissertation Repository

The imaging of structures in sedimentary basins has typically been carried out using conventional seismic reflection techniques. In complex geological architectures, such as those within the Superior Province in Canada, conventional seismic imaging yields suboptimal results due to factors stemming from complex energy scattering and crooked seismic geometries. Full-waveform inversion (FWI) is a nonlinear inverse technique capable of retrieving quantitative images of velocity structures. Judicious data preconditioning, and multiscale inversion strategies allow FWI to effectively estimate velocity variations in the first few kilometers of the subsurface. Non-conventional seismic reflection processing, based on azimuthal binning and enhanced migration velocity models, improves ...


Snow Covered With Dust After Chamoli Rockslide: Inference Based On High-Resolution Satellite Data, Sansar Raj Meena, Kushanav Bhuyan, Akshansha Chauhan, Ramesh P. Singh 2021 University of Twente

Snow Covered With Dust After Chamoli Rockslide: Inference Based On High-Resolution Satellite Data, Sansar Raj Meena, Kushanav Bhuyan, Akshansha Chauhan, Ramesh P. Singh

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The high-resolution multi-temporal PlanetScope image of 7 February 2021 clearly shows the fall of a large part of the Nanda Ghunti glacier (Uttarakhand) down in the base of the valley from a height of about 2000 m. The recorded seismic signals at the local seismic networks, close to the Joshimath station, show the occurrence of the fall of the first glacier block followed by another block which corresponds to the seismic signal recorded the second time. The timings of signals recorded from the seismic station are related to the visual sign of local dust in the valley after the fall ...


Ultralow Velocities Of Caco3 And The Origin Of Seismic Anomalies In The Earth's Upper Mantle, Mingqiang Hou, Ming Hao, Jin Liu, Xiaowan Su, Wen-Yi Zhou, Rostislav Hrubiak, Jin S. Zhang 2021 University of New Mexico

Ultralow Velocities Of Caco3 And The Origin Of Seismic Anomalies In The Earth's Upper Mantle, Mingqiang Hou, Ming Hao, Jin Liu, Xiaowan Su, Wen-Yi Zhou, Rostislav Hrubiak, Jin S. Zhang

Earth and Planetary Sciences Faculty and Staff Publications

Calcium carbonate (CaCO3) is a major host for CO2 in the deep Earth. The physical and chemical properties of CaCO3 at extreme pressure-temperature (P-T) conditions are indispensable to decipher the circulation of carbon between the Earth's interior and surface via volcanism and subduction. Using the pulse-echo-overlap method combined with Paris-Edinburgh press, we measured velocities of CaCO3 and observed an anomalous drop associated with the amorphization of aragonite under upper mantle conditions. The compressional (VP) and shear (VS) wave velocities of the partially amorphized CaCO3 are reduced by ~35% and 52% respectively, at ...


Digital Appendix Of Masters Thesis "Constraining Deformation Mechanisms Of Damage Zones: A Case Study Of The Shallow San Andreas Fault At Elizabeth Lake, Southern California, James P. Evans, Caroline Studnicky 2021 Utah State University

Digital Appendix Of Masters Thesis "Constraining Deformation Mechanisms Of Damage Zones: A Case Study Of The Shallow San Andreas Fault At Elizabeth Lake, Southern California, James P. Evans, Caroline Studnicky

Browse all Datasets

We performed macroscopic, optical petrographic, scanning electron microscopy, and geochemical analyses on rock core acquired across the San Andreas Fault at Elizabeth Lake, California, in order to understand the distribution and accommodation of fault-related slip and energy within the shallow damage zone of this continental scale strike-slip fault. We characterized the deformation structures, alteration textures, and elemental variabilities to constrain the properties of the uppermost ~2 km fault-related damage zone at this site. We identified evidence for coseismic slip in the form of pulverized rocks, injection veins, clay-clast aggregates, and pseudotachylyte, and aseismic slip through calcite twins, dilatant vein fills ...


Changes In Tropospheric Ozone Associated With Strong Earthquakes And Possible Mechanism, Feng Jing, Ramesh P. Singh 2021 China Earthquake Administration

Changes In Tropospheric Ozone Associated With Strong Earthquakes And Possible Mechanism, Feng Jing, Ramesh P. Singh

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The index of ozone anomaly (IOA) has been proposed to detect changes in tropospheric ozone associated with strong earthquakes. The tropospheric ozone prior and after the 2008 Wenchuan earthquake has been analyzed using IOA. Atmospheric infrared sounder ozone volume mixing ratio (O3 VMR) at different pressure levels (600, 500, 400, 300, 200 hPa) for an 18-year period 2003–2020 has been considered to identify the unique behavior associated with the strong earthquakes. Our results show distinct enhancement in tropospheric ozone occurred 5 d (7 May 2008) prior to the main event and distributed along the Longmenshan fault zone. An enhancement ...


Characterization Of Landslide Processes From Radar Remote Sensing And Hydromechanical Modeling, Yuankun Xu 2021 Southern Methodist University

Characterization Of Landslide Processes From Radar Remote Sensing And Hydromechanical Modeling, Yuankun Xu

Earth Sciences Theses and Dissertations

Landsides are a natural geomorphic process yet a dangerous hazard which annually causes thousands of casualties and billions of property loss in a global scale. Understanding landslide motion kinematics from early initiation to final deposition is critical for monitoring, assessing, and forecasting landslide movement in order to mitigate their hazards. Landslides occur under diverse environmental settings and appear in variable types; however, all types of landslides can be mechanically attributed to shearing failure at the basal surface due to stress regime shift contributed by internal and/or external forcing. Typical internal factors include soil/rock weathering, whereas typical external triggering ...


Enhancing Infrasonic Signal Detection And Event Localization Through Advanced Computational Methods, Fransiska Dannemann Dugick 2021 Southern Methodist University

Enhancing Infrasonic Signal Detection And Event Localization Through Advanced Computational Methods, Fransiska Dannemann Dugick

Earth Sciences Theses and Dissertations

The installation of worldwide infrasound and seismo-acoustic networks at both global and regional scales necessitates automated techniques and algorithms for accurate and efficient data processing and analysis. Signals recorded across the networks originate from a number of natural and anthropogenic sources. Data processing efforts focus on the separation of signals of interest from background noise, followed by the identification, or detection of signals of interest. Once signals are identified, association and location processing produces estimates of a signal's source. This dissertation focuses on the evaluation of automated processes for identifying and locating sources of interest.

Chapter two applies two ...


Spectral Ground Motion Characteristics Of Induced Earthquakes In The Fort Worth Basin, Texas, SeongJu Jeong 2021 Southern Methodist University

Spectral Ground Motion Characteristics Of Induced Earthquakes In The Fort Worth Basin, Texas, Seongju Jeong

Earth Sciences Theses and Dissertations

Concurrent with the development of unconventional oil and gas production, seismicity in the central United States has dramatically increased. Previous studies in many locations suggest that the earthquakes reactivate pre-existing faults, as a result of changing subsurface stresses due to injection of fluids from wastewater disposal wells. This sudden rise in seismicity rate motivates an assessment and possible mitigation of seismic hazard due to the proximity of induced seismicity to metropolitan areas like the Dallas-Fort Worth, Texas.

Successful assessment and mitigation of earthquake hazards requires estimates of ground motion parameters representing path attenuation, site effects and source characteristics constrained by ...


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