Earth Sciences Commons^™

How Geophysicists' Intuition Helps Seismic Data Processing, Afshin Gholamy, Vladik Kreinovich

Departmental Technical Reports (CS)

In geophysics, signals come with noise. It is desirable to minimize the effect of this noise. If we knew the probabilities of different values of signal and noise, we could use statistical filtering techniques. In geophysics, however, we rarely know the exact values of these probabilities; instead, we have to rely on the expertise and intuition of experts. We show how fuzzy techniques can transform this expertise into precise de-noising methods, we explain that the resulting methods indeed satisfy several natural requirements, and that these methods are in good accordance with heuristic techniques successfully used by geophysicists.

A Geophysical Study Of The Castle Mountain Fault System And Matanuska-Susitna Valley Near Anchorage, Alaska, Shane Michael Schinagel

Open Access Theses & Dissertations

The Castle Mountain Fault (CMF) is the closest (~50 km) active fault to Anchorage, Alaska. Located within the Matanuska and Susitna (Matsu) Valleys, the CMF shows repeated, unmistakable evidence for Holocene motion. Recent geologic studies estimate that this fault is capable of producing earthquakes of magnitude 7.0 - 7.1. The Anchorage metropolitan area (which includes the Matsu Valley) contains most of Alaska's population as well as vital shipping and transportation facilities that serve much of inland Alaska. Expected magnitude >7 earthquakes pose seismic hazards to the expanding Anchorage area.

While several mapping and trenching studies have been conducted along the …

Dynamic Triggering In The Coso Geothermal Field, 2004-2013, Richard A. Alfaro-Diaz

Open Access Theses & Dissertations

We take advantage of EarthScope’s USArray Transportable Array (TA), regional seismic networks to investigate 154 M ≥ 7 earthquakes over a ten-year period (2004- 2013), in search of remotely triggered seismicity within the continental United States. We conduct an automated search to detect high frequency signals (which may indicate triggering of small local earthquakes) using a time window of 5 hours before and after each mainshock. The automated detection applies a short-term average (STA) to long-term-average (LTA) algorithms, to create a catalogue of detections. Using the catalog we search for an increase in detection rates after each main-shock. Sharp increases …

Evaluating Methods Of Field-Based 3d Visualization And Their Application To Mapping Metamorphic Terranes: An Example From The Panamint Mountains, California, Jade Ashley Brush

Open Access Theses & Dissertations

Field geology has traditionally relied on 2D, paper-based workflows, but digital mapping techniques are rapidly replacing these outdated methods because they allow for more efficient and accurate mapping. This research applies digital mapping techniques and two terrestrially-based 3D visualization technologies, photogrammetry and Light Detection and Ranging (LiDAR), to the study of metamorphic terranes in the Panamint Mountains, California. This study reports on the spatial accuracy of TINs (triangulated irregular networks) generated from both photogrammetry and ground-based LiDAR using a terrestrial laser scanner (TLS) and discusses how spatial accuracy can be increased. Two levels of comparison were used to test spatial …

Understanding The Contractional History Of Surprise Canyon, California Through Digital Field Mapping, 3d Modeling, And U-Pb Zircon Geochronology, Joshua A. Cobb

Open Access Theses & Dissertations

Detailed digital mapping of lower-middle Surprise Canyon has revealed a more complex structure than previously interpreted. Rock units derived from the metamorphosed equivalents of the Pahrump Group exposed in Surprise Canyon display juxtapositions inconsistent with stratigraphic variations suggested in previous studies. This study proposes a contractional history of the central Panamint Mountains defined by two kinematically distinct and geochronologically constrained deformation events. D1 is characterized by a shallow dipping, NNW striking L and LS tectonite fabric ubiquitously observed in all metasedimentary and basement units. F1 folds are mesoscopic in scale and isoclinal with an axial planar S1 foliation. A prominent …

Quantifying Weathering Rates On Tropical Volcanic Basse-Terre Island, French Guadeloupe: Insights From U-Series Isotopes In Weathering Rinds, Jacqueline Engel

Open Access Theses & Dissertations

Weathering of volcanic rocks plays many important roles at Earth’s surface such as modifying landscapes, providing nutrients to soil, and regulating atmospheric CO2. U-series isotopes (e.g. 238U-234U-230Th and 232Th) have been established as a chronometer used to constrain the formation rates of weathering rinds in tropical island environments. Here, U-series isotopes and major element concentrations were analyzed in two basaltic-andesite weathering rinds collected from the Deshaies watershed located in the northern, relatively dry (mean annual precipitation (MAP) = 1800 mm) region of tropical Basse-Terre Island, Guadeloupe. The two clasts are referred to as clasts AN-14-7.5 and AN-14-7.6. Elemental mobility trends …

Receiver Function Analysis To Study Crustal Structure Of The Northern Nepal And Tibetan Plateau, Mohan Pant

Open Access Theses & Dissertations

The teleseismic P-waveform receiver function analysis is a commonly used technique in earthquake seismology to study the crustal structure beneath a broadband seismic station. To understand the structure of the Northern Nepal and Tibetan plateau different studies have used the receiver function method to estimate the Moho depth and Vp/Vs ratio. The value suggested was ~ 30 km in the south and the ~ 75 km in the north. Other studies have used teleseismic body wave data to perform the travel time residuals to model the lithosphere structure. In our study, we analyzed data from 261 seismic stations to establish …

Crustal Structure Beneath The Eastern Nepal Himalayas And Southern Tibet From Receiver Function Analysis, Arjun Sharma Neupane

Open Access Theses & Dissertations

The Himalayas are the results of continental collision between the Indian plate and the Eurasian plate and serve as a natural site to study the physical causes and process of mountain building. The crustal structure beneath the Himalayas has been subject to numerous geophysical studies and the variation in the velocity structure across the Himalayan region suggests significant differences in the crustal structure between the southern and northern portion in that region. In this research, a P receiver function analysis has been conducted on data collected for 14 years (2000-2014) from 211 different stations in Eastern Nepal and Southern Tibet, …

Trace Element Behavior During Coal Combustion: Insights From Cadmium And Zinc Isotope Analysis, Fotios Fouskas

Open Access Theses & Dissertations

Due to its low cost and abundance, coal has been pervasively used in recent decades to meet large energy demands worldwide. Coal combustion provides the dominant electrical source in the U.S and produces over 100 million tons of coal combustion products (CCPs) per year domestically. The disposal/beneficial use of CCPs has the potential to release toxic trace elements, including cadmium (Cd) and zinc (Zn), into the environment. High temperature combustion of coal changes both physical states and chemical properties of Cd and Zn compounds in CCPs. Related processes such as evaporation and condensation, can lead to mass-dependent fractionation of Cd …

Lithospheric Structure And Stress Field Orientations In The Northern Libya And East-Central Mediterranean Region, Abdusalam Ali Agail

Open Access Theses & Dissertations

This thesis is a combination of three studies including tomography using surface wave group velocities, stress orientations from focal mechanisms, and receiver functions. The study area covers northern Libya and the east central Mediterranean region. I utilized new data from the Libyan National Seismic Network to better understand the crustal thickness and stress orientation of northern Libya as well as the east central Mediterranean region. In the first study, I conducted surface wave group velocity tomography implementing the Gaussian beam method for obtaining 2-D velocity variations assuming an isotropic model. I constructed surface wave group velocity maps over a range …

A Tectonic Analysis On The Central Region Of The Himalaya Collision Zone Using Double Difference Tomography, Chanel Perez

Open Access Theses & Dissertations

The Himalaya mountain range remains the only place on Earth undergoing continuous effects from the continental-continental collision between India and Asia. Because of this, the Himalayas have been subjected to extensive deformation and transpression, and contain five major shear zones. Extensive seismic analysis of the region, however, is lacking due to sparse seismograph coverage and complexity of the crustal structure. I examined seismic event data from two temporary seismic networks deployed in the central Himalaya, the HIMNT deployment from 2001-2003, and the Bhutan deployment from 2002-2003. Using this data I develop a 3-D earth model for the region using double-difference …

Development Of 3-D Shear Wave Models Using A Multi-Objective Optimization Scheme, Lennox Emmanuel Thompson

Open Access Theses & Dissertations

Evidence of geologic activity still occurring in Rio Grande Rift (RGR) includes quaternary faulting, seismicity, and widening at a small rate. We map the crustal thickness and seismic velocity ratio to create crustal model cross sections that highlights the regional extension of the Southern Rio Grande Rift (SRGR). Specifically, we compute receiver functions and receiver function stacks for 147 USArray and previously collected data, and interpolate the crustal and velocity results using a kriging interpolation scheme. By incorporating gravity, magnetics, receiver functions, velocity models, and the interpretation of seismic reflection/refraction data, we produce a constrained crustal model that characterizes the …

Salt And Mineral Recovery From High Salinity Waters, Osvaldo Alejandro Broesicke

Open Access Theses & Dissertations

Natural salt springs in the Salt Fork Basin in Crosby County, Texas, result in the natural salt pollution of the Brazos River, rendering it unusable for most potable purposes. Previous research indicates that by intercepting the source of the pollution, water quality of the Brazos River can be greatly improved. This paper investigates and assesses two strategies for salt and mineral recovery using natural brine collected from the Salt Fork Basin, the first of which is presented in a separate work.

The research described in this paper evaluates the potential of a desulfation, soda-caustic softening, acidification/decarbonation, and evaporation process to …

Reinterpretation Of The Mesozoic Thrust Complex Of The Southern Spring Mountains, Nevada, Warren Harding Allen

Open Access Theses & Dissertations

The east verging Keystone thrust fault in the southern Spring Mountains west of Goodsprings, Nevada, is mapped with a sharp bend in its trace near Keystone Wash. This bend was previously explained in the context of out-of-sequence thrusting and a salient-recess relationship along the thrust system; a simple redirection of the Keystone thrust to a north verging thrust. Recent geochronological studies indicate that the east verging Keystone thrust to the north of Keystone Wash formed between 83-103Ma. Approximately 5 kilometers to the east a north verging branch of the fault system overlies rocks as young as 99Ma. At the location …

Depositional Facies And Interpretation Of Salt-Sediment Interaction In The Lower Triassic Moenkopi Formation Adjacent To The Castle Valley Salt Wall, Paradox Basin, Utah, Ann Marie Foster

Open Access Theses & Dissertations

Stratigraphic, sedimentologic and compositional data collected from the Triassic Moenkopi Formation adjacent to the Castle Valley salt anticline, Paradox Basin, Utah indicate passive diapirism of the salt wall with well-developed topography and exposed salt during the Early Triassic. Moenkopi strata thin to 150m on to the Castle Valley salt anticline and thicken to an estimated 275m away from it, indicating control of sedimentation by salt-generated topography. The distribution of nine terrestrial facies assemblages within Moenkopi Formation strata on the margins of Castle Valley Salt Wall, in combination with identification of three halokinetic sequences interpreted from stratal architecture adjacent to the …

Predicting Irrigation Efficiency In The Rio Grande Project, Gerardo Melendez

Open Access Theses & Dissertations

Surface water losses in the Bureau of Reclamation’s (USBR) Rio Grande Project have become more prevalent within the past few years of the drought of the 2000’s. Simple regressions were performed in order to find correlations and determine factors that may affect the flows within the Rio Grande Project. Correlations were found in the difference between Rio Grande below Caballo flows and Rio Grande at El Paso flows, and between the diversion ratio and groundwater levels. Caballo Reservoir release amounts were found to be fairly well correlated with the difference between the Rio Grande below Caballo and the Rio Grande …

Optimization Schemes For The Inversion Of Bouguer Gravity Anomalies, Azucena Zamora

Open Access Theses & Dissertations

Data sets obtained from measurable physical properties of the Earth structure have helped advance the understanding of its tectonic and structural processes and constitute key elements for resource prospecting. 2-Dimensional (2-D) and 3-D models obtained from the inversion of geophysical data sets are widely used to represent the structural composition of the Earth based on physical properties such as density, seismic wave velocities, magnetic susceptibility, conductivity, and resistivity. The inversion of each one of these data sets provides structural models whose consistency depends on the data collection process, methodology, and overall assumptions made in their individual mathematical processes. Although sampling …

Sequence Stratigraphy And Depositional Environment Of The Cambro-Ordovician Bliss Sandstone, Franklin Mountains Of El Paso, Texas, Drew Adam Chenoweth

Open Access Theses & Dissertations

The Bliss Formation formed along the Southwestern continental shelf of

Laurentia during the Late Cambrian and records the craton]wide Cambrian

transgression previously described by Sloss. This study divides the Bliss into five facies associations which were used to determine the depositional environments: 1) The Basal Transgressive Lag (BTL) was interpreted to be a high energy fluvial deposit the top of which has been reworked and winnowed during transgression. 2) The Lower Cyclic Sandstones and Silty Sandstones (LCSS) were interpreted to be be tidal delta or tidal estuary deposits composed of delta deposits, slackwater deposits, and tidal dunes within tidal channels. …

Geophysical Investigation Of Hot Springs In The Vicinity Of Shoshone, California, Felix Dziedzorm Ziwu

Open Access Theses & Dissertations

Magnetic and gravity surveys were conducted in the vicinity of Shoshone, California to test a hypothesis from investigating hotsprings within Tecopa and Saratoga which states that deep faults must intersect with a specific orientation relative to the regional stress field in order to create hot springs along the Amargosa River.

Three isolated basalt flows with different gravity and magnetic properties were identified near the Shoshone hot spring. Two of the flows have very low magnetic anomalies and the remaining one has a high magnetic anomaly. The high magnetic anomaly basalt flow also has a significantly higher Bouguer anomaly than the …

Long-Term Deformation In The Southern Rí­O Grande Rift As Inferred From Topographic And Uplifted Terraces, Linda K. Armour

Open Access Theses & Dissertations

This study examines Basin and Range topography relating tectonic processes to topographic features. The observation that the terraces along either side of the Franklin Mountains were deformed and uplifted is a reflection of tectonic uplift. The uplift represents long-term deformation of the range. This led to the question of what shapes the deformation and does it represent differential subsidence into the Río Grande Rift or true uplift. A more regional study of the Sacramento, San Andres, and Guadalupe Mountains follows. Two papers form this Dissertation.

The Rí­o Grande Rift and the Franklin Mountains, in particular, are the subject of the …

Analyzing Stress Drops Of Earthquakes Near Wellington, New Zealand, Kyle Eugene Barnes

Open Access Theses & Dissertations

Stress drop studies analyze the change of stress across faults before and after an earthquake. The goal of this study was to determine how stress drop varies throughout the Wellington region of the North Island of New Zealand. To the east of the North Island, the Hikurangi Trough obliquely subducts the Pacific Plate beneath the younger Australian Plate. Toward the southern end of the North Island and into Cook Strait the Pacific plate becomes more buoyant and the plate interface displays strong coupling as subduction diminishes into the strike-slip Marlborough fault system. Subduction of the Pacific plate ceases beneath the …

Sedimentologic, Stratigraphic, And Diagenetic Analysis Of Microbialite-Bearing Lacustrine Rift Sequence Within The Lower Cretaceous Yucca Formation, Indio Mountains, West Texas, Xiaowei Li

Open Access Theses & Dissertations

This study sedimentologically, stratigraphically, and diagenetically analyzed strata of the upper member of the Lower Cretaceous Yucca Formation in the Indio Mountains, West Texas in order to develop an outcrop-based analog model for similar facies that form major hydrocarbon reservoirs in the Pre-salt rift basins of the South Atlantic margin. The lower Cretaceous strata of the Indio Mountains were deposited in rift basins that formed along the eastern margin of the Chihuahua Trough under similar greenhouse climate conditions as the South Atlantic basins.

Eleven lithofacies are recognized from the upper member of the Yucca Formation to the base of the …

Exploring The Hydrogeologic Controls On Brackish Water And Its Suitability For Use In Hydraulic Fracturing: The Dockum Aquifer, Midland Basin, Texas, Francisco Ruben Reyes

Open Access Theses & Dissertations

Water scarcity in arid regions can limit or impede certain hydrocarbon production activities, such as hydraulic fracturing and well drilling. The Midland Basin, a major oil-producing area in semi-arid far west Texas and the eastern sub-basin of the Permian Basin, is already impacted by limited freshwater availability. A typical tight oil well in the Midland Basin requires ~3.8–11.4 × 103 m3 of water per fracture treatment (Nicot et al., 2012). Despite draught conditions and limited resources, data for 2011 indicate freshwater comprises ~70% of the water used in hydraulic fracturing in the Midland basin. Thus, the Midland Basin represents an …

Mapping Technologically And Economically Important Materials At Lunar And Terrestrial Sites Using Moon Mineralogy Mapper (M3) And Advanced Spaceborne Thermal Emission And Reflection Radiometer (Aster) Data, Douglas L. Standart

Open Access Theses & Dissertations

This Dissertation comprises three distinct research projects, all of which employ the use of remote sensing and digital image processing methods for the discovery and characterization of mineral resources. Two of the research projects focus on the use of hyperspectral data to identify water and ilmenite on the lunar surface. The third research project involves the use of multispectral data to map alunite in copper porphyry and epithermal silver-gold deposits. Our approach to these problems result in innovative algorithms and geological interpretations that are of use to both planetary science and exploration and the terrestrial mineral industry.

Project I: Towards …

Structural And Geochronologic History Of Southern Alaskan Blueschists, Erik M. Day

Open Access Theses & Dissertations

Detrital zircon data are presented from the Liberty Creek blueschist in the central Chugach Mountains which indicate two distinct periods of the preservation of blueschist facies metamorphism along the southern Alaskan margin. A maximum depositional age of ~136 Ma demonstrates that the Liberty Creek schist was deposited long after the Jurassic cooling ages (196-185 Ma; Lopez-Carmona et al., 2011) recorded in western Alaskan blueschist bodies, revealing two blueschist preservation events. This Early Cretaceous depositional age also indicates that there have been major reorganizations within this subduction complex because the Potter Creek assemblage, directly south of the Liberty Creek schist, is …

Depositional And Sequence Stratigraphic Framework Of An Exposed Neoproterozoic Suprasalt Minibasin At Patawarta Diapir, Flinders Ranges, South Australia, Cora Evelyn Gannaway

Open Access Theses & Dissertations

Outcrops of mixed carbonate/siliciclastic strata comprise the Neoproterozoic (Marinoan) Wilpena Group at Patawarta diapir in the Flinders Ranges, South Australia. Patawarta diapir is a ramping allochthonous salt sheet flanked by suprasalt and subsalt minibasin strata. The stratal and structural attributes of the coeval minibasin fills afford a unique perspective on lateral and vertical salt migration and the impacts of salt-modified bathymetry in shallow marine depositional environments. This study documents the depositional and diagenetic facies, stratal thickness trends, and structural style and stratal geometries of the suprasalt minibasin fill and correlates it to the previously studied subsalt minibasin fill. The goal …

Why Ricker Wavelets Are Successful In Processing Seismic Data: Towards A Theoretical Explanation, Afshin Gholamy Salehabady

Open Access Theses & Dissertations

In many engineering applications ranging from engineering seismology to petroleum engineering and civil engineering, processing seismic data plays a key role. In processing seismic data, it turns out to be very efficient to describe the signal's spectrum as a linear combination of Ricker wavelet spectra.

In this Thesis, we provide a possible theoretical explanation for this empirical efficiency. Specifically, signal propagation through several layers is discussed, and it is shown that the Ricker wavelet is the simplest non-trivial solution for the corresponding data processing problem, under the condition that the described properties of the approximation family are satisfied.

Geochemical Studies Of Backfill Aggregates, Lake Sediment Cores And The Hueco Bolson Aquifer, Anita Thapalia

Open Access Theses & Dissertations

This Dissertation comprises of three different researches that focuses on the application of geochemistry from aggregates, lake sediment cores and Hueco Bolson Aquifer. Each study is independent and presented in the publication format. The first chapter is already published and the second chapter is in revision phase. Overall, three studies measure the large scale (field) as well as bench scale (lab) water-rock interactions influenced by the climatic and anthropogenic factors spans from the field of environmental geology to civil engineering.

The first chapter of this Dissertation addresses the chemical evaluation of coarse aggregates from six different quarries in Texas. The …

Geophysical Model Of The Cu-Mo Porphyry Ore Deposit At Copper Flat Mine, Hillsboro, Sierra County, New Mexico, Adrian Emmanuel Gutierrez

Open Access Theses & Dissertations

A 3D gravity model of the Copper Flat Mine was performed as part of the exploration of new resources in at the mine. The project is located in the Las Animas Mining District in Sierra County, New Mexico. The mine has been producing ore since 1877 and is currently owned by the New Mexico Copper Corporation, which plans o bringing the closed copper mine back into production with innovation and a sustainable approach to mining development. The Project is located on the Eastern side of the Arizona-Sonora-New Mexico porphyry copper Belt of Cretaceous age. Copper Flat is predominantly a Cretaceous …

Development Of A Transferable Student Engagement And Knowledge Retention Framework For The Earth Sciences, Sunay Palsole

Open Access Theses & Dissertations

The earth sciences play an important role in engaging students in science and in science, technology, engineering and mathematics (STEM) disciplines, because of the integrative nature of the disciplines. It then becomes important for us to provide an engaging experience for students taking earth science courses, because it serves a dual purpose of possibly increasing new majors in the discipline and helping to create a science literate population.

Given that a majority of students in the larger introductory courses are non-majors, it behooves us to explore alternative engagement techniques and measure their efficacy in student engagement, which in turn can …