Geophysics and Seismology Commons^™

Effect Of Subsurface Microseismicity On The Motion Of Surrounding Dispersed Droplets: Supporting Information, Chao Zeng, Wen Deng

Research Data

The human-induced seismicity has called substantial attention in recent years. The effect of seismicity on the subsurface structure has been extensively studied. However, the effect of seismicity, especially those microseismicity, on surrounding immiscible fluids is rarely investigated. In porous media with two or more immiscible fluids, different amplitudes of vibration induced by seismicity have distinct effects on the dynamic behavior of fluids. Three types of pore-scale models are prevalent in the analysis of the motion of immiscible droplets. The underlying assumptions and accuracy of these models are compared in this study in both frequency domain and time domain. The frequency …

Abiotic Formation Of Dissolved Organic Sulfur In Anoxic Sediments Of Santa Barbara Basin, Hussain A. Abdulla, David J. Burdige, Tomoko Komada

OES Faculty Publications

Sulfurization has been found to enhance organic matter preservation and petroleum formation in marine sediments. However, we do not yet have a comprehensive understanding of sulfurization mechanisms. In this study, we investigated several possible mechanisms of dissolved organic sulfur (DOS) formation in the top 4.5 m of anoxic sediments of Santa Barbara Basin (SBB), California Borderland. Using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FTICR-MS), we identified chemical formulas of potential dissolved organic matter (DOM) precursors to these DOS compounds. We also examined how the formulas of abiotically formed DOS changed as a function of depth across a major redox …

Physical Modeling Of The Krauklis Waves: Insights From Two Experimental Apparatuses, Haitao Cao

Dissertations, Master's Theses and Master's Reports

Fractures play an important role in the geological related processes such as hydraulic fracturing, water-water disposal, and volcanic earthquake. Seismic waves can provide useful information from fractures at a relatively low cost. In particular, the acoustic property of fractures containing magmatic or hydrothermal fluids can provide useful information about the fracture size and the fluid composition within the fracture. For instance, in volcanology, the resonant frequency of long-period events that are linked to crack interface waves is used to obtain fluid properties of cracks in magmatic systems. However, in order to rely on seismic data, they should be precisely characterized …

Exploring Effects Of Gps Processing On Atmospheric And Hydrologic Pressure-Induced Crustal Responses, Cody T. Norberg

Undergraduate Theses, Professional Papers, and Capstone Artifacts

The Earth’s crust is in continuous motion from changes in fluid pressures associated with the redistribution of mass at the surface. These forces, known as surface mass loading, make up a significant amount of signal within GPS time series. This thesis is broken up into two projects exploring atmospheric and hydrologic pressure-induced crustal responses. The first project focuses on effects of GPS processing on corrections of atmospheric loading. We use data from over 1100 GPS stations within the Western US to investigate crustal displacements from atmospheric surface pressure variations. We find that modeling and removing atmospheric mass loading reduces root …

Onset And Cause Of Increased Seismic Activity Near Pecos, West Texas, United States, From Observations At The Lajitas Txar Seismic Array, Clive Frohlich, Chris Hayward, Julia Rosenblit, Chastity Aiken, Peter Henning, Alexandros Savvaidis, Casee Lemons, Elizabeth Horne, Multiple Additional Authors

Geology Faculty Publications and Presentations

In recent years, numerous small earthquakes have occurred near the town of Pecos in West Texas; however, when this activity began and whether it was caused by increased petroleum industry activity has been uncertain because prior to 2017 there were few permanent seismograph stations in the region. We identify and locate earthquakes using data recorded since 2000 at TXAR, a sensitive 10‐station seismic array situated about 240 km south of Pecos. We thus show that in 2007, one earthquake occurred near Pecos, in 2009 several more occurred, and subsequently, activity has increased considerably, with more than 2000 events identified in …

Determining Variable Depth To Bedrock Using Ert And Masw: A Geophysical Investigation In St. Louis, Mo, Justin James Clinton

Masters Theses

“The research involves a geophysical study in the Maremec River Valley in St. Louis County, Missouri. The geophysical methods described in this paper can provide a relatively quick, inexpensive, and accurate means in investigating the lithologic characteristics of the subsurface. Method selection is ultimately dependent of the type of investigation and site-specific characteristics. In this investigation, Electrical Resistivity Tomography (ERT) data and Mutli-Channel Analysis of Surface Waves (MASW) data were acquired to image the bedrock beneath the Maremec River to an approximate depth of 110 ft or an elevation of 300 ft for a proposed wastewater tunnel. Two overlapping dipole-dipole …

Strain Partitioning Across The Polochic-Motagua Fault System In Guatemala: Insight From Kinematic Modeling, Qiaoqi Sun

Masters Theses

”The Polochic-Motagua Fault System in Guatemala is the on-land segment of the sinistral transform plate boundary between the North American Plate and the Caribbean Plate. Three major seismically active strike-slip faults in this fault system pose significant earthquake threats to surrounding populated cities. The assessment of seismic hazard requires a better understanding of the kinematics of the fault system. GPS monitoring indicates that seventy-five percent of the ~20 mm/yr. plate motion is accommodated by the Motagua Fault and less than twenty-five percent is accommodated by the Polochic Fault. However, the Polochic Fault documents a lateral offset of ~132 ± 5 …

Lévy Processes: Characterizing Volcanic And Financial Time Series, Peter Kwadwo Asante

Open Access Theses & Dissertations

In this work, we use the Diffusion Entropy Analysis (DEA) to analyze and detect the scaling properties of time series from both emerging and well established markets as well as volcanic eruptions recorded by a seismic station, both financial and volcanic time series data are known to have high frequencies (i.e they are collected at an extremely fine scale). The objective is to determine the characterization i.e whether they follow a Gaussian or Lévy distribution. If they do follow a Lévy distribution we are then interested in finding if they are characterized by a Lévy walk which has a finite …

Shallow Seismic Modeling Of The Hydrothermal Plumbing System Beneath Old Faithful Geyser In The Upper Geyser Basin Of Yellowstone National Park, Jordan Rigdon Caylor

Open Access Theses & Dissertations

In November 2016, a 2-D and 3-D seismic survey was performed around Old Faithful Geyser in the southeastern portion of the Upper Geyser Basin in Yellowstone National Park. The survey consisted of 521 3-component seismic receiver locations including 39 receivers on a ~1km NE-SW trending line crossing Old Faithful Geyser. A 5.4kg sledgehammer striking a metal plate was our source with a dominant frequency of ~40Hz. Our 2-D line crosses Old Faithful in a NE-SW direction with station spacing at 25-30m with ~100m spacing on either side of Old Faithful and a total length of 1024m. Our 3-D seismic grid …

Geophysical Investigations Of The San Andreas Fault System And Evaluations In Geoscience Education, Sandra Hardy

Open Access Theses & Dissertations

Chapter 1: Investigating Earthquake Cycle Vertical Deformation Recorded by GPS And Regional Tide Gauge Stations in California

Geodetic and tide gauge measurements of vertical deformation record localized zones of uplift and subsidence that may document critical components of both long and short-period earthquake cycle deformation. In this study, we compare vertical tide gauge data from the Permanent Service for Mean Sea Level (PSMSL) and vertical GPS data from the EarthScope Plate Boundary Observatory (PBO) for 10 approximately co-located station pairs along coastal California from Point Reyes, CA to Ensenada, Mexico. To compare these two data sets, we first truncate both …

Application Of Non-Seismic Methods To Analyze And Model The Geometry Of The Northern Margin Of The Onion Creek Salt Diapir, Paradox Basin, Utah, Julia Michelle Astromovich

Open Access Theses & Dissertations

The Onion Creek salt diapir lies within the Paradox Basin of Utah where it forms part of a series of salt walls that separate the Paradox Basin into smaller sub-basins. These sub-basins and associated salt diapirs remain key to several oil and gas traps in the region. A series of anomalous tight folds occur on the northern side of the Onion Creek diapir within the Permian Cutler Group Undifferentiated. These folds are thought to be associated with a shallow detachment horizon with three possible origins:1) a weak shale layer within the Cutler Group, 2) a salt shoulder, or 3) a …

Active Seismic Studies In Lemon Creek Valley Glacier, Juneau, Alaska: Characterization Of Subglacial Sediments To Understand Glacier Dynamics, Lucia Fernanda Gonzalez

Open Access Theses & Dissertations

Deformation and flow properties of subglacial sediments as well as the presence and volume of water at the ice/bed interface strongly influence glacier dynamics. Studies of Lemon Creek Glacier, a small temperate valley glacier in the Juneau Icefield, near Juneau, Alaska, have shown that the glacier is rapidly retreating, with a negative mass balance every year since 1957. However, the bed topography and properties of subglacial sediments at the base of Lemon Creek Glacier remained unknown until now. In this project, we process and interpret ~1-km-long NW-SE trending active-source seismic reflection profiles collected during June and July 2017 near the …

A Machine Learning And Data-Driven Prediction And Inversion Of Reservoir Brittleness From Geophysical Logs And Seismic Signals: A Case Study In Southwest Pennsylvania, Central Appalachian Basin, Tobi Micheal Ore

Graduate Theses, Dissertations, and Problem Reports (ETD)

In unconventional reservoir sweet-spot identification, brittleness is an important parameter that is used as an easiness measure of production from low permeability reservoirs. In shaly reservoirs, production is realized from hydraulic fracturing, which depends on how brittle the rock is–as it opens natural fractures and also creates new fractures. A measure of brittleness, brittleness index, is obtained through elastic properties of the rock. In practice, problems arise using this method to predict brittleness because of the limited availability of elastic logs.

To address this issue, machine learning techniques are adopted to predict brittleness at well locations from readily available geophysical …

Microseismic Evidence For Bookshelf Faulting In Western Montana, Ellen Mcgough Smith

Graduate Student Theses, Dissertations, & Professional Papers

One of the most seismically active regions in the western United States, far from any major plate boundary, is the Intermountain Seismic Belt (ISB). On 6 July 2017, a M5.8 earthquake occurred 11 km southeast of Lincoln, Montana within the ISB. This was the largest earthquake to occur in the state of Montana since the 1959 M7.3 Hebgen Lake earthquake. Data from the University of Montana Seismic Network (UMSN), the Montana Regional Seismic Network (MRSN), and the United States Geological Survey (USGS) were used to investigate the aftershock sequences following the M5.8 Lincoln event. We have manually picked P- and …

Geophysical Characteristics Of Nickel And Copper Deposits In Wadi Al Khadra Prospect, Southwestern Of Saudi Arabia, Abdulrahman Ahmed Aljabbab

Doctoral Dissertations

“Three geophysical datasets (self-potential, magnetics, and time - domain electromagnetics) were acquired at Wadi Al Khadra Ni-Cu prospect in southwest Saudi Arabia, and were processed and interpreted for the Saudi Geological Survey. The primary objectives were to map the distribution of metallic mineralization, map structures, verify the integration of the geophysical interpretations and its signatures in conjunction with boreholes information, distinguish the similarities and differences in the integrated interpretation of geophysical data, and design optimal processing and interpretation data parameters. The self-potential tool was used to map the variation in natural surface potential differences to map lateral variations in the …

Geophysical Assessment Of The Lake Chesterfield Site, Missouri, Diya Ali Ahmad Alfuqara

Doctoral Dissertations

"Since construction of the Lake Chesterfield, Missouri in 1986, significant leaks have occurred causing the lake to lose substantive volumes of water. Mitigation efforts, have not solved the problem. Indeed, in June of 2017, the water level in Lake Chesterfield dropped at an alarmingly rapid rate. Prior to authorizing additional mitigation work, the Lake Chesterfield. Home Owners Association (LCHOA) decided to acquire geophysical data across the drained and dry lake bed. These information would help a geotechnical engineering firm determine the most appropriate mitigation plan.

In the summer of 2018, electrical resistivity tomography, multichannel analysis of surface wave, and spontaneous-potential …

A Broad Iceland Plume Associated With Two Phase Transitions At The 660 Km Discontinuity: Constraints From Receiver Functions, Dan Wang

Doctoral Dissertations

"In spite of the fact that Iceland is frequently regarded as the archetypal example of mantle plumes, the existence, depth extent, origin, dimension and excess temperature of the hypothesized plume remain enigmatic and hotly debated. The controversy mostly originates from the limited vertical resolution of seismic tomography techniques and the associated uncertainty in the depth and lateral extents of the lower wavespeed anomaly. Here we utilize a robust receiver-function-based technique to image the topography of the 410 and 660 km discontinuities bordering the mantle transition zone beneath Iceland and surrounding oceanic regions, and construct thermal and seismic wavespeed models of …

Seismological Investigations Of Lithospheric Structure Beneath The East African Rift System And The Kalahari Craton, Tuo Wang

Doctoral Dissertations

"In spite of numerous geophysical studies have been conducted in East African Rift System and Southern Africa, the structure and evolution of the crust and upper mantle are still controversial. In this study, we applied multiple seismological techniques to investigate the structure in the crust and uppermost mantle beneath the East African Rift System and Kalahari Craton in southern Africa. First, the technique of ambient noise tomography was applied to image shear wave velocity model from surface to the depth of 40 km beneath the Malawi and Luangwa rift zones. For the first time, a high-resolution 3-D shear wave velocity …

Atmospheric And Ionospheric Responses To Acoustic And Gravity Waves Driven By Earthquakes And Tsunamis, Pavel A. Inchin

Doctoral Dissertations and Master's Theses

Natural hazards (NHs) are causes for significant concern due to their potentially catastrophic impacts on society. The study of their effects on the upper atmosphere can provide significant insight into the coupled nature of geophysical processes, and drives important applications for radio communication and navigation, leading potentially to the development of NH early-warning systems. Although general concepts underlying their coupling mechanisms are well understood, recent computational capabilities, supported by high temporal and spatial density of observations, have reached the level where such processes can be modeled with unprecedented realism for detailed case studies. The studies provided in this thesis are …

Stochastic Inversion Integrating Seismic Data, Litho-Facies Physical Properties, And Multiple-Point Geostatistics For Reservoir Characterization, Mohamed Mohamed

Dissertations, Master's Theses and Master's Reports

We proposed a novel seismic inversion approach that integrates the physical properties of litho-facies, and geophysical data, within the multiple-point geostatistical frameworks to reduce the uncertainty in predictions of litho-facies spatial arrangement away from wells or control points. The litho-facies groups (rock-type) in the well locations are defined and conditioned to the distribution of elastic properties, including P-wave velocity (Vp) and facies density (ρ) in the well locations. A conceptual geological model (training image) is utilized within a wavelet-based multiple-point geostatistical simulation (WAVESIM) algorithm to generate litho-facies realizations. In our inversion algorithm, the forward model is created by implementing the …