Geophysics and Seismology Commons^™

An Integrated Geophysical Survey Of Kilbourne Hole, Southern New Mexico: Implications For Near Surface Exploration Of Mars And The Moon, Nisa Maksim

Open Access Theses & Dissertations

Features such as the Home Plate plateau on Mars, a suspected remnant of an ancient phreatomagmatic eruption, can reveal important information about paleohydrologic conditions. The eruption intensity of a phreatomagmatic volcano is controlled mainly by the quantity of water and magma, the internal geometry of the volcano, and the depth of the interaction zone between magma and water. In order to understand the paleohydrologic conditions at the time of eruption, we must understand all the factors that influenced the phreatomagmatic event. I conducted an integrated geophysical survey, which are magnetic and gravity surveys, and a ground-penetrating radar (GPR) surveys at …

3-D Structure Of Colombia From 1-D Constrained Joint Inversion Of Receiver Functions And Surface Wave Dispersion, Nick Talavera

Open Access Theses & Dissertations

The country, Colombia, resides at the northwest corner of the South America with seismicity and volcanism due to the intersections of the Nazca, South America and Caribbean tectonic plates (Figure 1). The boundaries of the South America plate, on which Colombia lies, borders between 60 to 200 kilometers from its coasts. A dense spot of seismicity known as the Bucaramanga Nest has had many theories to explain its existence. Two tectonic microplates suspected in this region have not been well understood. With many mysteries of the behavior of the tectonic plates beneath Colombia, using new methods may shed light on …

Seismic Modeling, Rock Physics, Avo And Seismic Attribute Analysis For Illuminating Sandstone Facies Of The Late Ordovic Ian Mamuniyat Reservoir, R-Field, Murzuq Basin-Libya, Yousf Milad Abushalah

Open Access Theses & Dissertations

The Late Ordovician Mamuniyat Formation is the main hydrocarbon reservoir in the R-Field in Murzuq Basin, SW Libya. The Lower Mamuniyat, which is the only unit that was encountered in the study area, is composed of sandstone facies called Clean Mamuniyat and shaly sandstone facies called Dirty Mamuniyat. One major problem with the development of the R-Field is the difficulty of distinguishing the two units so this project was aimed to develop better methods for distinguishing between the two units of the Lower Mamuniyat. The other problem is to distinguish the transgressive shaly facies of the Bir Tlacsin, which has …

Evidence Of Active Rifts In The Southwest United States Using Geophysical Inversion Of Seismic Data, Sergio H. Celis

Open Access Theses & Dissertations

A continental rift represents a zone where the lithosphere has become thinner due to extensional forces associated with plate tectonics. Many of these rifts are still active, such as the East Africa rift, while others appear to be failed rifts. I build upon recent results of crustal structure for the southern section of the Rio Grande Rift using seismic data collected by USArray stations, and extend the analysis into the states of New Mexico, Oklahoma, Arkansas, and Louisiana to investigate the differences between active and failed rifts in the state of Texas. I collect two geophysical data sets, including receiver …

A Geophysical Investigation At The Potrillo Maar, Manuel Moncada Gutierrez

Open Access Theses & Dissertations

The Potrillo Volcanic Field (PVF) is a unique geological site located in Doña Ana County the southernmost part of New Mexico, and part of northern part of Chihuahua, Mexico. The main feature of the southern PVF is Potrillo Maar. This maar-volcano straddles the international boundary between United States and Mexico and lies within the southern part of the Rio Grande Rift. The Potrillo Maar was formed about 20,000 years ago in three major events that formed basalt lava flows and ejecta deposits that consist of crustal and mantle xenoliths.

The purpose of this Thesis is to determine the area of …

Kinematic Constraints On Tectonics Of The Northern Basin And Range, Dylan Schmeelk

Graduate Student Theses, Dissertations, & Professional Papers

We derive surface velocities relative to North America, using data from 1989 through 2014 in the interior northwest, to investigate kinematics from the Snake River Plain (SRP) to the Canadian border. The Centennial Tectonic Belt (CTB) exhibits similarities to the main Basin and Range Province (BRP) that suggest the CTB is an extension of the BRP, including range and fault orientation, increasing velocity magnitudes westward, and a distinct high rate of strain across the Madison Range. Calculations of fault spreading rates and orientations from geodetic data show that several faults are more active than previously assumed when compared to seismic …

Influence Of The Weathered Layer On Retrieving Body Wave Using Passive Siesmic Interferometry, Boming Wu

Dissertations, Master's Theses and Master's Reports

Passive seismic interferometry (SI) is an increasingly popular seismic method due to its cost-efficient advantage because it does not need an active source. Techniques in using SI to retrieve surface waves are relatively well established, but using SI to retrieve body waves is still under development by many authors. These geophysicists have proved that many factors, such as average duration of the natural sources, the number of natural sources that occurred during recording time, source distribution, etc., influence the quality of body waves retrieved. In this research, I focus on how to make use of the attenuation property of weathered …

Petrophysical And Empirical And Theoretical Rock Physics Modeling For The Moki Formation In Two Fields In The Taranaki Basin, New Zealand, Deniz Yener

Dissertations, Master's Theses and Master's Reports

This work consists of conventional petrophysical analysis and sonic response determination from empirical relations, rock physics modelling, and fluid substitution for six wells in the Moki formation of New Zealand’s Taranaki Basin. The project composed of three parts encompassing conventional log analysis, rock-physics modeling using empirical and theoretical approaches, and finally rock-physics modeling for shaley sands using semi-empirical adaptations to Gassmann fluid substitution. Finally, comparisons are made between results for the different wells, based on their depths and mineralogy.

The first part of this study is presented as a petrophysical analysis, including crossplot analysis, conventional 3-mineral identification approach, and determination …

Cave Detection Using Seismic Methods At Madison Blue Spring State Park, Madison County, Florida, Charles Breithaupt

Dissertations, Master's Theses and Master's Reports

Locating caves and quantifying their geometries has significant importance in aquifer characterization, sinkhole mitigation, and contaminant transport monitoring. Several geophysical methods have been used for cave detection with limited success, but no reliable solution has been found. New developments in seismic techniques, however, show promising results indicating that cave voids may be more accurately detected.

We evaluated the capability of several seismic techniques to detect caves by collecting new seismic data over a known conduit connected to Madison Blue Spring, in northern Florida. These analyses validated the abilities of diffracted surface waves to detect water-filled caves by viewing these data …

Enhancement Of Margrave Deconvolution And Q Estimation In Highly Attenuating Media Using The Modified S-Transform, Adnan Djeffal

Dissertations, Master's Theses and Master's Reports

We evaluate the performance of the Margrave deconvolution and spectral ratio methods using the Gabor, S-, and modified S transforms in highly attenuating media, where the quality factor changes with depth dramatically. Our results substantiate that the modified S-transform deconvolution is more robust in terms of generating fewer artifacts and providing better estimates of reflectivities than the Gabor transform. The results also show that using the modified S-transform in the spectral ratio method produces better Q estimates than the S-transform and the Fourier transform that is conventionally used in the spectral ratio method. This improvement in the estimates of reflectivities …

Reservoir Characterization Through Pre-Stack Seismic Analysis And Inversion In The Thrace Basin, Northwest Turkey, Emre Doguturk

Dissertations, Master's Theses and Master's Reports

This study analyzes hydrocarbon reservoirs by using Amplitude-Versus-Offset (AVO) analysis and different inversion methods to investigate hydrocarbon reservoir in the Thrace Basin which is located in northwest Turkey.

A 3D seismic survey containing prestack data was provided by Turkish Petroleum Corporation as true amplitude NMO corrected 3D gathers.

The quality of this land data was poor for AVO applications, and steps were taken to make it useful. Radon filtering proved to be extremely useful for this purpose. Although application of this filter affected the AVO characteristics differently depending on the parameters selected for the filter, relative AVO characteristics remained useful …

Preliminary Seismic Coda Wave Attenuation Study Of Pacaya Volcano, Guatemala, Maximilian Guettinger

Dissertations, Master's Theses and Master's Reports

Pacaya volcano is a basaltic complex in the Central American Volcanic Arc in Guatemala. Pacaya has been in an open vent condition since 1961. During January 2015 we deployed 19 short period seismometer stations on Pacaya at distances less than 1.5 kilometers from the summit. The resulting data consisted of tremor and thousands of discrete events associated with ongoing outgassing. Where possible, individual events were identified and located. They were found to be high in the edifice near the vent. We used the decaying codas of these events to model the attenuation structure of the Pacaya edifice, following the energy …

Spatiotemporal Slip Rate Variations Along Surprise Valley Fault In Relation To Pleistocene Pluvial Lakes, Brian N. Marion

All Master's Theses

Using mapped paleoshoreline features with high-resolution topographic data and obtained radiocarbon dates on paleoshoreline tufas, I documented precise fault offsets of dated features over the last 25 ka along the Surprise Valley Fault (SVF). Fault offset measured in three lake sections within Surprise Valley ranged from 3.6 m in the southern section to 14.4 m in the central section. The offset paleoshorelines are dated to the late Pleistocene (<22 >ka) and were formed during the latest impoundment of pluvial Lake Surprise since the last glacial maximum. Slip rates vary along strike, assuming a fault dip of 68° with 0.25 ± …

3d Structural And Stratigraphic Architecture Of The Northwest Santa Barbara Basin And Implications For Submarine Landslide Generation, Alexis Wright

Dissertations and Theses

Multiple submarine landslides have been previously documented on the north flank of the Santa Barbara Channel, and such failures are considered to be capable of generating local tsunamis hazards to the Santa Barbara region. 2D seismic-reflection datasets provide a general view of regional framework geology, including faulting and folding associated with north-south compression. However, better understanding of the relationships between faults, folds, stratigraphic architecture, and submarine landslides can be obtained with 3D seismic datasets. In this study we use an industry 3D seismic-reflection volume that encompasses the slope and shelfbreak surrounding the Gaviota submarine landslide (3.8 km2) to investigate structural …

The Martian Surface Radiation Environment- A Comparison Of Models And Msl/Rad Measurements, Daniel Matthiä, Bent Ehresmann, Henning Lohf, Jan Köhler, Cary Zeitlin, Jan Appel, John W. Wilson

Mathematics & Statistics Faculty Publications

Context: The Radiation Assessment Detector (RAD) on the Mars Science Laboratory (MSL) has been measuring the radiation environment on the surface of Mars since August 6th 2012. MSL-RAD is the first instrument to provide detailed information about charged and neutral particle spectra and dose rates on the Martian surface, and one of the primary objectives of the RAD investigation is to help improve and validate current radiation transport models.

Aims: Applying different numerical transport models with boundary conditions derived from the MSL-RAD environment the goal of this work was to both provide predictions for the particle spectra and the radiation …

Earthquakes And Seismology, John J. Renton, Thomas Repine

Readings and Notes

The great majority of earthquakes are caused by the movement of faults. Two terms are used to determine the location of an earthquake, focus and epicenter. The focus of an earthquake is the point along a fault where the rocks slipped and released the energy previously stored during the elastic phase of deformation. Because faults represent brittle deformation, the highest frequency of earthquakes occurs at Earth's surface and decreases with depth as rocks become less brittle and more plastic. The deepest earthquake foci occur at depths of about 640 km. ( 400 mi.) which is the deepest penetration of subducting …

Earthquakes, John J. Renton, Thomas Repine

Readings and Notes

For centuries, earth scientists have known where the major earthquakes occurred. They also knew they occurred in the same locales as the most violent volcanoes, a fact that led to centuries of arguments as to which was the cause of the other. Now we know that they are not cause and effect; they are both associated with the convergent plate margins. During the mid-1900s, another major zone of both volcanic and earthquake activity was discovered, namely the divergent margins, the most important site being the oceanic ridges. Since then, we have also come to understand the occurrence of volcanic activity …

Spatial Scaling Of Crustal And Lithospheric Deformation In The Western United States, Cody W. Bomberger

Graduate Student Theses, Dissertations, & Professional Papers

Deformation of continental lithosphere can extend great distances laterally from tectonic plate boundaries. This extent has been used to argue for a variety of constitutive laws for continental materials, based on the underlying principles in continuum mechanics that identify a relationship between characteristic spatial scale and material properties. Although the relationship between observed deformation and material models is always non-unique, quantifying one or more characteristic scales of deformation in a region can rule out some models of how the lithosphere deforms. In the western United States active deformation occurs at the plate boundary between North America and either the Pacific …

Assessment Of Highway Condition Using Combined Geophysical Surveys, Abdallah Alhadi Dera

Doctoral Dissertations

"Four pavement sections were investigated using ground penetrating radar (GPR) and Ultrasonic Surface Wave (USW). The objective of this research was to compare the effectiveness of two non-destructive geophysical tools, GPR and the PSPA, in assessing the condition of the pavements, composed of different construction materials. The GPR data were acquired using a 1.5 GHz antenna along five traverses spaced at two ft. intervals approximately 1000 ft. long. On the other hand, the PSPA data were acquired at the stations spaced at 1000 ft. along the five GPR traverses. Core samples were collected at each site to constrain the interpretation …

Azimuthal Anisotropy Beneath North Central Africa From Shear Wave Splitting Analysis, Awad Abdussalam Henish Lemnifi

Doctoral Dissertations

"This study represents the first multi-station investigation of azimuthal anisotropy beneath the interior of north central Africa, including Libya and adjacent regions, using shear wave splitting (SWS) analysis. Data used in the study include recently available broadband seismic data obtained from 15 stations managed by the Libyan Center for Remote Sensing and Space Science, and those from five other stations at which data are publicly accessible. A total of 583 pairs of high-quality SWS measurements utilizing the PKS, SKKS, and SKS phases demonstrate primarily N-S fast orientations with an average splitting delay time of approximately 1.2 s. An absence of …