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Structural Analysis Of The Northwest Wind Mountain Quadrangle, New Mexico: Proterozoic Shearing To Cenozoic Brittle Faulting In The Burro Mountains, Jensen Kohl Angelloz 2017 Stephen F. Austin State University

Structural Analysis Of The Northwest Wind Mountain Quadrangle, New Mexico: Proterozoic Shearing To Cenozoic Brittle Faulting In The Burro Mountains, Jensen Kohl Angelloz

Electronic Theses and Dissertations

Preliminary investigation of the Bullard Peak metamorphic series (BPMS) in the northwestern Wind Mountain quadrangle within the Burro Mountains of southwestern New Mexico suggests a possible previously unidentified shear zone, prompting detailed (1:12,000) geologic mapping and collection of structural data. The study area has a complex tectonic history, including 1) ~1.65 Ga metamorphism during accretion of the Mazatzal terrane to Laurentia’s southern margin; 2) ~1.4 Ga intrusion of Granite and Rhyolite Province granitoids; 3) significant uplift during the formation of the Ancestral Rockies (~300 Ma) and the Rocky Mountains (~70-50 Ma); and 4) inversion tectonics ...


Geology Of The Northern Alto Relex Area, Big Bend National Park, Brewster County, Texas, Robert Schoen 2017 Stephen F. Austin State University

Geology Of The Northern Alto Relex Area, Big Bend National Park, Brewster County, Texas, Robert Schoen

Electronic Theses and Dissertations

Detailed, 1:12,000-scale geologic field mapping was conducted around Alto Relex in the northern Sierra Del Carmen Mountains in Big Bend National Park. Alto Relex is a prominent, near vertical, ~1000 foot-high fault-line scarp. Cretaceous rocks in the area were folded and faulted by Laramide compression, intruded by Tertiary sills and overprinted by high-angle normal faults from Basin and Range extension. During the Laramide Orogeny and Basin and Range extension, the underlying basement shear zone called, the Texas Lineament, was reactivated creating a transpressional and transtensional regimes. The general geology of this area was outlined by Moustafa (1988) working ...


Paleomagnetic Results From Luzon And The Central Philippines, Robert McCabe, Eichi Kikawa, Jay T. Cole, Ariel J. Malicse, Paul E. Baldauf, Jun Yumul, Jose Almasco 2017 Texas A&M University

Paleomagnetic Results From Luzon And The Central Philippines, Robert Mccabe, Eichi Kikawa, Jay T. Cole, Ariel J. Malicse, Paul E. Baldauf, Jun Yumul, Jose Almasco

Paul Baldauf

Samples were collected from 86 paleomagnetic sites from the islands of Luzon, Marinduque, Mindoro, Panay, Negros, Cebu, and Mindanao in the Philippine Arc. The sampling sites range in age from Pleistocene to Jurassic. Characteristic directions of magnetization of the samples were determined by the use of vector plots. Curie temperature determinations, thin section studies, and hysteresis studies showed that remanence of these samples is carried by fine-grained (pseudo-single domain) magnetite. Positive fold tests from Miocene data from Panay, Jurassic data from Mindoro, and Cretaceous data from Cebu suggest that the magnetization of these regions was acquired prior to folding. Rotations ...


The Impact Of Fe-Ti Oxide Concentration On The Structural Ridgity Of The Lower Oceanic Crust, Atlantis Bank, Southwest Indian Ridge, Daniel Winkler 2017 University of Southern Mississippi

The Impact Of Fe-Ti Oxide Concentration On The Structural Ridgity Of The Lower Oceanic Crust, Atlantis Bank, Southwest Indian Ridge, Daniel Winkler

Master's Theses

Fe-Ti oxides are important components of oceanic core complexes (OCC) formed at slow-spreading mid-ocean ridges since Fe-Ti oxides are more susceptible to crystal-plastic deformation than silicate minerals. This study investigated the predicted relationship between the presence and concentration of Fe-Ti oxides and the presence and intensity of crystal-plastic deformation in gabbroic samples from Atlantis Bank, Southwest Indian Ridge (SWIR). Atlantis Bank is an oceanic core complex that formed through the exhumation of lower oceanic crust along a detachment fault. OCCs form along slow-spreading ridges and are characterized by the complex interactions between magmatism and lithospheric extension, thus making these complexes ...


Paleogeography Of Early Paleozoic Laurentia And Meguma, Avalonia Terranes Via Paleomagnetism And Faunal Review, Halima S. Warsame 2017 The University of Western Ontario

Paleogeography Of Early Paleozoic Laurentia And Meguma, Avalonia Terranes Via Paleomagnetism And Faunal Review, Halima S. Warsame

Electronic Thesis and Dissertation Repository

Paleomagnetic assessment of 821 Cambrian to Silurian-aged rock specimens of igneous and sedimentary origin was used as a means to provide insight on the ancient geographies of the region in which these rocks are currently found. The Earth’s magnetic field direction can be recorded at the time of rock formation and/or at a later significant event by magnetic minerals, allowing these signatures to be used to track the past motions of the continents. Stepwise demagnetization of the Port au Port, St. George and Table Head Groups in western Newfoundland, and the Mavillette gabbro (426 +/- 2 Ma, U-Pb baddeleyite ...


A Study Of Marine Terrace Formation Along The California Central Coast, Mary C. Devlin 2017 California Polytechnic State University, San Luis Obispo

A Study Of Marine Terrace Formation Along The California Central Coast, Mary C. Devlin

Natural Resources Management and Environmental Sciences

Marine terrace formation is in many instances attributed to wave action, and shore platforms are often called “wave-cut”. However, alternative models for marine terrace formation suggest that other types of physical and chemical weathering have a more central role in the formation of marine terraces than is widely acknowledged. Roering and Retallack (2012) concluded that the roles of subaerial physical and chemical weathering are significant, and played a major role in the formation of the terraces. In this study, weathering of beach cliffs and shore platforms associated with marine terraces at eight sites in two different locations along the central ...


Further Study Of Garnet Xenocrysts In New York City Migmatites, Stanley Schleifer, Nazrul I. Khandaker 2017 York College CUNY

Further Study Of Garnet Xenocrysts In New York City Migmatites, Stanley Schleifer, Nazrul I. Khandaker

Publications and Research

The authors have previously published an article at the 2004 Geological Society of America Annual Meeting, Petrogenetic Significance of Garnets in the Bedrock of New York City, in which they suggested that the garnet xenocrysts observed in the quartzofeldspathic zones of the migmatites, so frequently seen both at the surface, and below the surface pursuant to the construction of the Manhattan portion of New york City Water Tunnel #3, were a refractory residue of the anatectic melting of the immediately surrounding schistose bedrock. Although the relatively high melting point temperature of garnet compared to other minerals in the surrounding schists ...


In Situ Dating Of Multiple Events In Granulite-Facies Rocks Of The Larsemann Hills, Prydz Bay, East Antarctica Using Electron Microprobe Analysis Of Monazite, Steven K. Spreitzer 2017 University of Maine

In Situ Dating Of Multiple Events In Granulite-Facies Rocks Of The Larsemann Hills, Prydz Bay, East Antarctica Using Electron Microprobe Analysis Of Monazite, Steven K. Spreitzer

Electronic Theses and Dissertations

The metamorphic rocks exposed along the southeast coast of Prydz Bay were affected by several metamorphic and plutonic events associated with collision in the Neoproterozoic and Cambrian. Critical units exposed in the Larsemann Hills and nearby ice-free areas include (1) basement Søstrene Orthogneiss, (2) cover sequence Brattstrand Paragneiss and (3) anatectic pegmatites intrusive into the Brattstrand Paragneiss. Zircon U-Pb data from previous studies yielded a maximum depositional age of 1023 ± 19 Ma for the Brattstrand Paragneiss, but only approximate ca. 900 Ma to ca. 1000 Ma and ca. 530 Ma ages for two metamorphic events. In order to constrain the ...


The Dynamic Relationship Between The Bear River, Quaternary Basaltic Center, Normal Faults, And The Resulting Rearrangement Of Rivers In The Northeast Edge Of The Great Basin, Southeast Idaho, Brady Utley 2017 Utah State University

The Dynamic Relationship Between The Bear River, Quaternary Basaltic Center, Normal Faults, And The Resulting Rearrangement Of Rivers In The Northeast Edge Of The Great Basin, Southeast Idaho, Brady Utley

All Graduate Plan B and other Reports

The objective of this research project in Gem Valley graben, southeast Idaho is to identify the location, age and history of the Quaternary diversion of the Bear River into paleo-Lake Thatcher, and then into the Lake Bonneville basin from the Columbia River basin. Mapping, geochemical analysis, cross-cutting relationships, and five new age determinations, together with prior published research, shed new light on the complex history of interaction between the volcanic rocks, rivers, lakes, and faults in Gem Valley. Research goals were to test the hypothesis that local faulting and volcanism drove the diversion of the Bear River and controlled the ...


Constraining The Spatial Extent Of Strain Localization At The Base Of The Seismogenic Zone: A Case Study From The Sandhill Corner Shear Zone, Maine, Usa, Erik Kristian Anderson 2017 University of Maine

Constraining The Spatial Extent Of Strain Localization At The Base Of The Seismogenic Zone: A Case Study From The Sandhill Corner Shear Zone, Maine, Usa, Erik Kristian Anderson

Electronic Theses and Dissertations

Knowledge of the structure and processes of strain localization at the base of the seismogenic zone can provide constraints on the rheologic evolution of shear zones at depth and the spatial extent that seismicity influences the surrounding rock. Such knowledge is hindered by limitations of borehole measurements from such depths and a lack of structural/mineralogical preservation of original rock fabric. The Sandhill Corner Shear Zone, Maine, USA provides an opportunity to study well-preserved structures relating to strain localization along major faults exhumed from seismogenic depths. In south-central Maine, this shear zone juxtaposes two rock types: the Cape Elizabeth Formation ...


A Case Study In Basement And Surface Structure Relationships And Their Implications For Fault Reactivation, Sawtooth Range, Mt, Jason M. Palu 2017 University of Nebraska-Lincoln

A Case Study In Basement And Surface Structure Relationships And Their Implications For Fault Reactivation, Sawtooth Range, Mt, Jason M. Palu

Dissertations & Theses in Earth and Atmospheric Sciences

The reactivation of pre-existing basement structures affects the geometry of subsequent deformation structures. A case study analyzing the results of these interactions can be used to examine multiple fold-thrust systems and lead to valuable deformation predictions. These predictions include the potential for hydrocarbon traps or seismic risk in an actively deforming area. This case study examined the development of structures close to the Augusta Syncline in the Sawtooth Range, Montana (USA), using: 1) an ArcGIS map of basement structures, based on analysis of gravimetric and aeromagnetic data, seismic data, and well logs; 2) an ArcGIS map of the surface deformation ...


Investigation Of Wing Crack Formation With A Combined Phase-Field And Experimental Approach, Sanghyun Lee, Jacqueline E. Reber, Nicholas W. Hayman, Mary F. Wheeler 2017 University of Texas at Austin

Investigation Of Wing Crack Formation With A Combined Phase-Field And Experimental Approach, Sanghyun Lee, Jacqueline E. Reber, Nicholas W. Hayman, Mary F. Wheeler

Jacqueline Reber

Fractures that propagate off of weak slip planes are known as wing cracks and often play important roles in both tectonic deformation and fluid flow across reservoir seals. Previous numerical models have produced the basic kinematics of wing crack openings but generally have not been able to capture fracture geometries seen in nature. Here we present both a phase-field modeling approach and a physical experiment using gelatin for a wing crack formation. By treating the fracture surfaces as diffusive zones instead of as discontinuities, the phase-field model does not require consideration of unpredictable rock properties or stress inhomogeneities around crack ...


Physical Experiments Of Tectonic Deformation And Processes: Building A Strong Community, Michael L. Cooke, Jacqueline E. Reber, Saad Haq 2017 University of Massachusetts Amherst

Physical Experiments Of Tectonic Deformation And Processes: Building A Strong Community, Michael L. Cooke, Jacqueline E. Reber, Saad Haq

Jacqueline Reber

The recent revolution in the analysis of physical experiments of tectonic processes has provided new quantitative tools to analyze their outcomes. Physical experiments using scaled analog models are unique in providing information on complex three-dimensional deformation where processes can be directly observed. These observations critically complement insights gained from field and analytical/numerical investigations. Recent innovations in rheologic testing, digital image processing, and data collection are revolutionizing how we use experiments to provide insight into crustal deformation. At the same time, we are seeing the benefits of physical experiments in classroom teaching by engaging students in hypothesis testing and hands-on ...


Stick-Slip And Creep Behavior In Lubricated Granular Material: Insights Into The Brittle-Ductile Transition, Jacqueline E. Reber, Nicholas W. Hayman, Luc L. Lavier 2017 Iowa State University

Stick-Slip And Creep Behavior In Lubricated Granular Material: Insights Into The Brittle-Ductile Transition, Jacqueline E. Reber, Nicholas W. Hayman, Luc L. Lavier

Jacqueline Reber

Crustal deformation can occur via stick-slip events, viscous creep, or strain transients at variable rates. Here we explore such strain transients with physical experiments comprising a quasi-two-dimensional shear zone with elastic, acrylic discs and interstitial viscous silicone. Experiments of solely elastic discs produce stick-slip events and an overall (constant volume) strengthening. The addition of the viscous silicone enhances localization but does not greatly change the overall pattern of strengthening. It does, however, damp the stick-slip events, leading to transient, creep-like behavior that approaches the behavior of a Maxwell body. There is no gradual transition from frictional to viscous deformation with ...


Structural And Stratigraphic Reconstruction Of The Whiting Dome Salt Structure In Viosca Knoll-Mississippi Canyon, Gom, Using 3d Seismic Data, Matthew R. Worrell 2017 Stephen F Austin State University

Structural And Stratigraphic Reconstruction Of The Whiting Dome Salt Structure In Viosca Knoll-Mississippi Canyon, Gom, Using 3d Seismic Data, Matthew R. Worrell

Electronic Theses and Dissertations

Understanding the complexities of salt tectonics is one of the most important factors regarding seismic interpretation of stratigraphy, structure, and geomorphology in the Gulf of Mexico. Evaluating the processes affecting recent mobilization of salt in the shallow, well-imaged section can help provide analogues for older, similar occurrences in the deeper section, thereby providing structural models for the autochthonous salt and its effect on stratigraphy and even potential timing and migration issues of hydrocarbons.

Progradation of delta front and shelf to slope transitional sediments has expulsed and emplaced an allochthonous salt structure (Whiting Dome) in the Viosca Knoll and Mississippi Canyon ...


Gravitational Study Of The Hastings Salt Dome And Associated Faults In Brazoria And Galveston Counties,Texas, Francis C. Okocha 2017 Stephen F. Austin State University

Gravitational Study Of The Hastings Salt Dome And Associated Faults In Brazoria And Galveston Counties,Texas, Francis C. Okocha

Electronic Theses and Dissertations

Salt domes are important geological structures because they are potential major hydrocarbon traps and have a profound effect on overlying strata in the subsurface. Over five hundred salt domes have been located on the United States Gulf Coast region, including the Hastings Salt Dome. Hastings Oil Field is located about 40.2 km (25 miles) southeast of Houston, Texas. The Hasting oil field was discovered in 1934 and it was considered the largest oil reserve on the Gulf Coast. Its peak production of 75,000 BOPD (barrels of oil per day) was recorded in 1977 and it had a cumulative ...


Basement And Cover Structural Analysis Along The Eagle River Gorge, Sawatch Range, Colorado, Kaitlin Lee Askelson 2017 Stephen F Austin State University

Basement And Cover Structural Analysis Along The Eagle River Gorge, Sawatch Range, Colorado, Kaitlin Lee Askelson

Electronic Theses and Dissertations

The Sawatch Range within the Rocky Mountains of central Colorado exposes Paleoproterozoic basement and overlying Paleozoic sedimentary rocks with a complex history of ductile and brittle deformation.

The goal of this study is to conduct analyses of brittle structures that occur in the basement and cover units to determine geometric relationships between the structures, provide a detailed description of structures and refine a geologic history for structures along the basement-cover contact in the northeastern Sawatch Range along the Eagle River canyon and U.S. Highway 24 from Red Cliff to Gilman, Colorado. Paleoproterozoic basement rocks include the Cross Creek granite ...


Impacts On The Stakeholders Of The Nexus Pipeline, Jessica A. Speweike 2017 Bowling Green State University

Impacts On The Stakeholders Of The Nexus Pipeline, Jessica A. Speweike

Honors Projects

This journalistic feature covers the different impacts on those individuals who are involved with or affected by the Nexus Gas Transmission pipeline. Testimony from Ohio landowners, activists, scientists and public officials cover a variety of opinions and concerns raised by the pipeline. Private property rights, environmental impact, and possible economic implications are detailed by those who have been involved with the Nexus pipeline since its early stages of implementation.


A Geophysical Analysis Of The Great Falls Tectonic Zone And The Surrounding Area, Montana Usa, Travis Lane Fultz 2017 Missouri State University

A Geophysical Analysis Of The Great Falls Tectonic Zone And The Surrounding Area, Montana Usa, Travis Lane Fultz

MSU Graduate Theses

The Great Falls Tectonic Zone (GFTZ) is a northeast trending zone of high angle faults and lineaments extending from northeastern Idaho into Saskatchewan, Canada. The GFTZ is believed to have facilitated the collision between the Archean Wyoming and Hearne cratons. Previous geophysical studies have analyzed seismic refraction data across the boundary between the Paleoproterozoic GFTZ and Archean Wyoming Craton (WC), this indicated the lower crustal layer thickens as it dips beneath the boundary towards the WC. In this study, three 2 dimensional (2D) gravity models that crossed the central region of the GFTZ were produced using constraints from existing geologic ...


Lithospheric Evaluation Of The Mid-Continental Rift System In Iowa From A Gravity And Magnetic Analysis, Moamen Mohamed Almaz 2017 Missouri State University

Lithospheric Evaluation Of The Mid-Continental Rift System In Iowa From A Gravity And Magnetic Analysis, Moamen Mohamed Almaz

MSU Graduate Theses

The Proterozoic Midcontinent Rift System (MCRS) is considered one of the most important tectonic features in North America and was formed during a continental breakup event at 1.1 Ga (billion years). The MCRS is totally covered by Phanerozoic sedimentary rocks except in the Lake Superior region. Consequently, the geological characteristics of the MCRS are primarily inferred from extrapolations from the outcrop areas, drill holes, and from a variety of geophysical investigations. Iowa has a large segment of the MCRS which to date has only been partially investigated geophysically with little information regarding the lower crustal and upper mantle structure ...


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