Physical Sciences and Mathematics Commons^™

The Regression Of The Flood In Virginia, James C. Rakestraw, Jim Melnick

Proceedings of the International Conference on Creationism

The geology, tectonics, and hydraulics of the regression of the Flood formed much of the geomorphology of Virginia. Opportunities to view and study geology and geomorphology are available through visiting parks, traveling on public roads, and viewing geographic information system (GIS) resources.

Virginia is part of the North American Plate. A series of “blocks” of basement rocks within the plate underlie the geomorphological provinces of Virginia. These “blocks” form a series of steps between the Atlantic Ocean Basin and the Blue Ridge. The “Fall Line” found in Virginia is a fault between two blocks of basement rock. The basement rocks …

Geothermal Gradient Variation In The Büyük Menderes Graben: Implications For Geothermal Potential Of The Graben, Western Anatolia, Türkiye, Adrian Wiggins,, İbrahim Çemen

Bulletin of the Mineral Research and Exploration

The Büyük Menderes Graben (BMG) is an E-W oriented active extensional geothermal basin within the Menderes Massif, a metamorphic core complex, in Western Anatolia, Türkiye. 1500 (megawattsenergy) MWe of installed geothermal capacity for power production exist as of December 2019 in Western Anatolia, mostly generated in the BMG. While the BMG is a vastly producing geothermal resource, it is predicted that it has higher production potential. However, other studies do not include field scale 3D geologic models or geothermal gradient maps. This study aims to first quantitatively test the geothermal gradients in the Aydın-İncirliova-Osmanbükü Geothermal Field (IGF), then map the …

Enhancing Earthquake Detection Through Machine Learning- An Application To The 2017 Mw 8.2 Tehuantepec Earthquake In Mexico, Marc Adrian Garcia

Open Access Theses & Dissertations

The Tehuantepec seismic gap, located off the southern shore of Oaxaca and Chiapas, Mexico, was previously thought to be an aseismic zone due to no significant event in 100 years. The September 8, 2017 (M8.2) Tehuantepec earthquake disproved this idea and added many questions surrounding the Mexican subduction zone. Specifically, the earthquake did not occur at the subduction megathrust. It ruptured the subducting plate below the megathrust and appeared to stop at the megathrust. Following this event, as well as the September 19, 2017 (M7.1) Morelos-Puebla earthquake, researchers from the University of Texas at El Paso (UTEP), Universidad Autónoma Cuidad …

Variations In Coupling And Deformation Along The Hellenic Subduction Zone, Michael Floyd, Robert King, Demitris Paradissis, Hayrullah Karabulut, Semi̇h Ergi̇ntav, Kostas Raptakis, Robert Reilinger

Turkish Journal of Earth Sciences

GNSS observations in and around the Aegean Sea, Peloponnese, and western Turkey are sufficiently precise and densely spaced to provide an image of the deformation associated with the Hellenic subduction zone. To isolate deformation associated with the plate boundary, we use GNSS secular velocities and shallow earthquake locations to determine an upper plate reference frame with low internal deformation (/yr) that includes a large area of the central and western Aegean. We interpret upper plate deformation as resulting from stronger coupling on the subduction plate interface beneath western Crete than on the western or eastern segments of the Hellenic subduction …

First-Row Transition Element Distribution Across The Blueschist-Eclogite Transition: A Case Study From New Caledonia, Natalie M. Harmon

Electronic Theses and Dissertations

The first-row transition elements (FRTE), namely Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn, are potential redox tracers in the solid Earth due to their general compatibility during crustal processes, and the redox-sensitive nature of certain elements. Despite widespread interest in the FRTEs, their distribution and behavior in subduction zones, particularly across the blueschist-eclogite transition, are still poorly constrained. New Caledonia preserves a prograde subduction zone with largely coherent continuous progression in metamorphic grade. Although the metamorphic sequence has been disrupted to some extent, this is the closest natural example of blueschist and eclogite that was sourced …

Mesozoic Sevier Thrusts Overprinted By Miocene-Quaternary Left-Lateral Deformation: Structures And Tectonism Of The Kane Springs Wash Region, Nevada, Andrew Reid

UNLV Theses, Dissertations, Professional Papers, and Capstones

Recognizing how rifts develop through space and time is vital to enrich our understanding of continental breakup. Rifts are commonly segmented by transfer or accommodations zones that form as the rift develops due to differences in the onset, direction, magnitude, or rates of extension on either side of the transfer or accommodation zone. The Basin and Range province is a wide rift where Cenozoic extension overprints and exposes earlier Mesozoic Sevier fold-thrust belt shortening structures. This exposure allows Sevier thrust correlations between individual mountain ranges and use of these shortening structures to study rift segmentation by strike-slip transfer faults. The …

Sulfuric Acid Speleogenesis And Surface Landform Evolution Along The Vienna Basin Transfer Fault: Plavecký Karst, Slovakia, Pavel Bella, Helena Hercman, Šimon Kdýr, Petr Mikysek, Petr Pruner, Juraj Littva, Jozef Minár, Michal Gradzinski, Wojciech Wróblewski, Marek Velšmid, Pavel Bosak

International Journal of Speleology

Hypogene caves in the Plavecký hradný vrch Hill (Western Slovakia, Central Europe) were formed by waters ascending along faults in fractured Triassic carbonates related to the horst-graben structure at the contact of the Malé Karpaty Mountains and the NE part of the Vienna Basin. The Plavecká jaskyňa and Pec caves mostly contain horizontal passages and chambers with flat corrosion bedrock floors, fissure discharge feeders, wall water-table notches, replacement pockets, as well as a few other speleogens associated with sulfuric acid speleogenesis. The low-temperature sulfuric acid development phases of the Plavecká Jaskyňa are also indicated by the presence of sulfate minerals …

Structural Geology And Cenozoic Deformation: Western Northern Range, Trinidad, Abigail Faye Clark

Geology: Student Scholarship & Creative Works

The Northern Range, Trinidad underwent deformation due to oblique collision of Caribbean plate with northern South America, which was then followed by transform plate motion. Deformation began in the late Miocene when sedimentary protoliths were ductility deformed and metamorphosed to greenschist facies; this event and subsequent transform deformation drove exhumation of these rocks to the surface and created their high topography. This project provides constraints of the structural history of the western Northern Range where bedrock mapping and structural analyses are most complete. Initial geologic mapping of Northern Range, which continued from the 1950s,1960s, and 1990s, focused on attempting to …

Thickness Of Fluvial Deposits Records Climate Oscillations, Xiaoping Yuan, Laure Guerit, Jean Braun, Delphine Rouby, Charles Shobe

Faculty & Staff Scholarship

Fluvial deposits offer Earth’s best-preserved geomorphic record of past climate change over geological timescales. However, quantitatively extracting this information remains challenging in part due to the complexity of erosion, sediment transport and deposition processes and how each of them responds to climate. Furthermore, sedimentary basins have the potential to temporarily store sediments, and rivers subsequently rework those sediments. This may introduce time lags into sedimentary signals and obscure any direct correlation with climate forcing. Here, using a numerical model that combines all three processes—and a new analytical solution—we show that the thickness of fluvial deposits at the outlet of a …

Late Triassic To Jurassic Magmatic And Tectonic Evolution Of The Intermontane Terranes In Yukon, Northern Canadian Cordillera: Transition From Arc To Syn-Collisional Magmatism And Post-Collisional Lithospheric Delamination, Maurice Colpron, Patrick J. Sack, James L. Crowley, Luke P. Beranek, Murray M. Allan

Geosciences Faculty Publications and Presentations

End-on arc collision and onset of the northern Cordilleran orogen is recorded in Late Triassic to Jurassic plutons in the Intermontane terranes of Yukon, and in development of the synorogenic Whitehorse trough (WT). A synthesis of the extensive data set for these plutons supports interpretation of the magmatic and tectonic evolution of the northern Intermontane terranes. Late Triassic juvenile plutons that locally intrude the Yukon-Tanana terrane represent the northern extension of arc magmatism within Stikinia. Early Jurassic plutons that intrude Stikinia and Yukon-Tanana terranes were emplaced during crustal thickening (200–195 Ma) and subsequent exhumation (190–178 Ma). The syn-collisional magmatism migrated …

Syn- To Post-Orogenic Evolution Of Collisional Mountain Systems: Investigating The Potential For Crustal Flow Using Thermochronology And Numerical Models, Brandon Spencer

Theses and Dissertations--Earth and Environmental Sciences

This dissertation is composed of three distinct manuscripts which collectively investigate processes that contribute to the late evolution of collisional mountain systems —specifically, the ancient Appalachian-Caledonian system. In the first paper, ⁴⁰Ar/³⁹Ar thermochronological data are used to constrain the timing of exhumation of the Scandian orogenic wedge of northern Scotland. Muscovite and amphibole samples yield dates of ca. 420-411 Ma, consistent with cooling after peak orogenesis. During this cooling phase, dates from both systems in individual thrust sheets show an increase in cooling rate in the later stage of exhumation; in the orogenic core, the cooling rate …

The Birth And Incision History Of The San Juan River In The Past 5 Ma, Micael T. Albonico

Earth and Planetary Sciences ETDs

This study addresses the evolution of the San Juan River system and its confluence with the Colorado River, ~ 100 km above the regionally important Lees Ferry knickzone. The San Juan River is a 600-km-long continental-scale tributary of the Colorado River. From its headwaters in the San Juan Mountains in Colorado, the San Juan River flows across the Colorado Plateau, and into the Colorado River upstream of Grand Canyon. Published apatite fission track and apatite (U-Th)/He thermochronologic data show that rocks in Marble Canyon, as well as in middle and upper reaches of the San Juan River, were >75 °C …

Geological Structures And Crustal Architecture Of The Cascadia Subduction Zone From The Integration Of Multiple Geophysical Datasets, Asif Ashraf

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The Cascadia subduction zone (CSZ) has a high potential for an inevitable and devastating megathrust earthquake. This margin is characterized by a complex seismicity pattern. Particularly in Oregon, there is a seismically quiescent zone bounded by high seismicity regions to the north and south. To comprehend these variations in seismicity, it is important to study the differences in crustal architectures and physical properties (densities and magnetic susceptibilities) along the CSZ. The primary objectives are to develop two plate-scale 2D integrated models through different seismicity zones and to map major tectonic structures from filtered potential fields. The Juan de Fuca oceanic …

Spatial And Temporal Patterns Of River Incision And Terrace Deposition In Response To Climate And Tectonics In Southern Taiwan, Dominique M. Shore

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Geologists often look at the Earth’s surface to understand the underlying processes that cause mountain formation. As tectonic forces drive uplift of Earth’s surface, processes of erosion transport sediment to lower elevations. Climate can play a large role in landscape formation as well as increased precipitation, accelerating rates of erosion. Rivers leave markers of landscape evolution through terrace landforms, former river floodplains that are left behind when rivers incise into a valley. To better understand landscape response to uplift, this research investigated the initial linkages between uplift, hillslope erosion (mass wasting) and river incision. At some point, it is thought …

Structural And Thermochronologic Evidence Of Paleogene-Neogene Faulting And Exhumation Of The Klamath Mountain Province, Taylor C. Team

Cal Poly Humboldt theses and projects

The Klamath Mountains Province (KMP), located at the southern end of the forearc of the Cascadia Subduction Zone, displays a distinct topographic and geologic signature. Compared to the forearc in the north, the KMP comprises Paleozoic-Mesozoic basement rocks with relatively high modern elevation and relief. This study investigates the pattern of rock cooling in the KMP by using thermochronology on plutons exhumed by faults and plutons outside of mapped faults. In this study, I target three regions in the KMP: the Ashland pluton offset by the Siskiyou Summit fault in the northeast KMP, the Grayback pluton in the northwest KMP, …

Crustal Evolution Of The New England Appalachians: The Rise And Fall Of A Long-Lived Orogenic Plateau, Ian Hillenbrand

Masters Theses

The rise and demise of mountain belts, caused by growth, modification, or removal of the continental lithosphere are fundamental processes that influence almost all Earth systems. Understanding the nature, timing, and significance of active processes in the creation and evolution of modern mountain belts is challenged by a lack of middle crustal and lower crustal exposures. Analogues can be found in ancient orogens, whose deeply eroded roots offer a window into deeper processes, yet this record is complicated by overprinting events and complex deformational histories. Research presented herein constrains the tectonic history of multistage Appalachian Orogen, type locality of the …

Integrated Studies Of Intracontinental Deformation In The Interior Western Usa, Cretaceous To Recent, Jacob Oliver Thacker

Earth and Planetary Sciences ETDs

The advent of plate tectonic theory satisfactorily explained a number of deformation belts around the world. However intracontinental deformation (deformation inboard of a plate margin) remains poorly understood in plate tectonic models. In order to further our understanding of intracontinental tectonics and its effects, this dissertation examines paleotectonic and neotectonic settings within the interior western USA.

Chapter 1 focuses on late Miocene–Recent deformation inboard of the San Andreas plate margin fault and its role on the integration history of the lower Colorado River. The neotectonic analysis included geometric and kinematic fault data collected in key geologic units to characterize the …

Band Extension And Possible Ridge Compression On Europa, Sarah Chinski

Macalester Journal of Physics and Astronomy

Jupiter's icy moon Europa has captivated and perplexed the scientific community since the discovery of its global liquid water ocean. Over the course of several missions to the Jovian system, high-resolution observations of Europa have determined that there are spreading zones where new crust is created, similar to the mid-ocean spreading tectonic process we observe on Earth. These features, known as bands, have symmetric hills and valleys, indicating brief events of activity where material from the interior is exuded through a central crack, and solidifies on both sides, creating two positive topography. Recently, Europan scientists have been questioning how these …

Stratigraphic Studies Of Late Albian Strata, North-Eastern Alberta., Arwa Zourob

Electronic Thesis and Dissertation Repository

Late Albian rocks of the Upper Viking, Westgate and lower Fish Scales alloformations were deposited about 101-100 Ma in the Western Canada Foreland Basin. Sediments in the study area span the forebulge, and are dominated by mudstone which forms 5-15 m thick, siltier-or sandier-upward sucessions bounded by marine flooding surfaces. Stratification is on a mm scale and represents storm deposits and fluid muds. Viking allomember VD and Westgate allomembers WA, WB and WC all thin towards the E and S and progressively onlap the forebulge. They record relative sea-level rise and gradual drowning and subsidence of the forebulge. In contrast, …

Testing Interpretations Of The Displacement Magnitude Of The Teton Fault And Uplift Of The Teton Range, Wyoming With Integrated Flexural-Kinematic And Thermal Modeling, Autumn Helfrich

Theses and Dissertations--Earth and Environmental Sciences

The Teton fault is a range-front normal fault in northwestern Wyoming. Previous estimates of the maximum displacement (D_max) on the Teton fault cover a wide range (2 - 11 km). Discrepancies also exist regarding the slip onset timing, which spans 2 - 13 Ma. To address these discrepancies, the exhumation history of the Teton Range is here investigated using forward flexural-kinematic (Move) and thermal-kinematic (Pecube) models that can be compared with previously reported apatite fission track (AFT) and apatite (U-Th)/He (AHe) ages from Mount Moran, which has been previously hypothesized to represent the …

Slip Rates And Kinematics Of Active Crustal Faults In The Central Oregon Cascades, Katherine Alexander

WWU Graduate School Collection

New cosmogenic ³He chronologies and surficial geologic mapping constrain the age of glacial deposits and slip rates of predominantly normal faults in the White Branch and Dilman Meadows fault zones in central Oregon, USA, over the last ca. ~80 kyr. Our mapping of glacial landforms and deposits distinguishes three primary episodes of glacial deposition in the White Branch fault zone. Twenty-two new cosmogenic ³He surface exposure dates indicate that the youngest glacial unit represents a last glacial maximum deposit (ca. 19.4 +10.1/-6.2 kyr). Mapping of outwash terrace surfaces and deposits in the Dilman Meadows fault zone, constrained by …

Applying Garnet And Zircon Ree Linkages To Determine Timing Of P-T Conditions And Tectonic Implications For Uhp Eclogites And Hp Granulites, Dulan Uhp Terrane, China, Wesley Weisberg

All Master's Theses

The Dulan ultrahigh-pressure (UHP) terrane in western China hosts rocks that record continental collision, however; the timing of peak P-T conditions in UHP eclogites and HP granulites, and the tectonic significance of their spatial relationship within the Dulan UHP terrane are not well understood. This study, (1) evaluates rare earth element (REE) equilibrium between garnet and zircon, to assess coeval growth; (2) links timing (from zircon) to the P-T history (from garnet) to constrain the P-T-t path of the Dulan UHP terrane and interpret implications for zircon growth; (3) refines P-T conditions for HP granulite; and (4) evaluates the tectonic …

Structural And Geochronologic Constraints On The Duration Of The Picuris Orogeny And Demise Of An Orogenic Plateau, Northern Nm, Daniel J. Young

Earth and Planetary Sciences ETDs

Metasedimentary and igneous basement rocks in northern New Mexico record episodic pulses of tectonism during cratonic growth from 1.8 to 1.38 Ga. Continued challenges involve parsing the deformational features attributable to the Yavapai Orogeny (1.71-1.68 Ga), Mazatzal orogeny (1.66-1.60 Ga), and Picuris orogeny (1.5-1.38 Ga) in this region and understanding how older structures may have been overprinted and reactivated to explain the observed strain. This paper presents regional cross-sections of the 1.7 Ga Vadito, 1.68 to 1.50 Ga Hondo, and 1.5-1.45 Ga Trampas groups of the Picuris Mountains and Rio Mora areas of northern New Mexico combined with new geochronologic …

Innovations In (U–Th)/He, Fission Track, And Trapped Charge Thermochronometry With Applications To Earthquakes, Weathering, Surface‐Mantle Connections, And The Growth And Decay Of Mountains, Alexis K. Ault, Cécile Gautheron, Georgina E. King

Geosciences Faculty Publications

A transformative advance in Earth science is the development of low‐temperature thermochronometry to date Earth surface processes or quantify the thermal evolution of rocks through time. Grand challenges and new directions in low‐temperature thermochronometry involve pushing the boundaries of these techniques to decipher thermal histories operative over seconds to hundreds of millions of years, in recent or deep geologic time and from the perspective of atoms to mountain belts. Here we highlight innovation in bedrock and detrital fission track, (U–Th)/He, and trapped charge thermochronometry, as well as thermal history modeling that enable fresh perspectives on Earth science problems. These developments …

Determining Rates Of Landscape Response To Tectonic Forcing Across A Range Of Temporal Scales And Erosional Mechanisms: Teton Range, Wy, Meredith Swallom

Theses and Dissertations--Earth and Environmental Sciences

Understanding how mountain landscapes respond to variations in tectonic forcing over a range of temporal scales in active mountain belts remains as a prominent challenge in tectonic and geomorphological studies. Although a number of empirical and numerical studies have examined this problem, many of them were complicated by issues of scale and climatic variability. More specifically, the relative efficiencies of fluvial and glacial erosion, which are presumably controlled by climate, are difficult to unravel. The Teton Range in Wyoming, which results from motion on the crustal-scale Teton fault, is an ideal natural laboratory for addressing this challenge as the tectonic …

Slip And Strain Accumulation Along The Sadie Creek Fault, Olympic Peninsula, Washington, Cody Duckworth

WWU Graduate School Collection

Upper-plate faulting in the Olympic Peninsula of Washington State reflects the interaction of crustal blocks within the Cascadia forearc as well as contributions from various earthquake cycle processes along the Cascadia subduction zone (CSZ). These processes include interseismic coupling, megathrust earthquakes, and aseismic slow slip events. In this study I utilize high resolution airborne lidar, field mapping of deformed surficial deposits and landforms, optically stimulated luminescence (OSL) dating and radiocarbon dating to reconstruct fault slip rates since Late Pleistocene deglaciation on the Sadie Creek fault (SCF), located north of the Olympic Mountains. This mapping reveals the SCF as a ~14 …

Characterizing The Deformation History Of The Southern Mina Deflection: Field And Structural Studies In The Huntoon Mountains, California-Nevada, Joseph Bodie Mccosby

All Master's Theses

New geologic mapping and structural studies in the Huntoon Mountain area (HMA), California-Nevada document the volcanic and deformation histories across the south-central Mina Deflection (MD). Our work allows us to (a) test whether present-day GPS predicted sinistral slip rates are the same as geologic slip rates in the southern MD, and (b) determine the kinematics of fault slip is transfer through the MD. The HMA exposes primarily Miocene andesitic-dacitic volcanic rocks overlain by the 12.114 ± 0.006 Ma (⁴⁰Ar/³⁹Ar sanidine, Petronis et al., 2019) Tuff of Jack Spring and the 11.399 ± 0.041 Ma (^{40 …}

Crustal Seismic Anisotropy Of The Ruby Mountains Core Complex And Surrounding Northern Basin And Range, Justin T. Wilgus

Earth and Planetary Sciences ETDs

Metamorphic core complexes (MCC) are distinctive uplifts that expose deeply exhumed and deformed crustal rocks due to localized extensional deformation. Consequently, their detailed structure provide a window into deep crustal mechanics. The North American Cordillera contains numerous MCC, one of which is the Ruby Mountains core complex (RMCC) located in the highly extended northern Basin and Range. To constrain the extent to which anisotropy below the RMCC deviates from the regional Basin and Range average and test the depth dependence of crustal anisotropy we conduct a radial anisotropy investigation below the RMCC and surrounding northern Basin and Range. Data from …

Unroofing History Of The Northwestern Ethiopian Plateau: Insights From Low-Temperature Apatite Thermochronology, Shelby Bowden

Masters Theses & Specialist Projects

The geology of Ethiopia is dominated by the Ethiopian Plateau that is similar in elevation to, but aerially larger than, the Colorado Plateau. Several rivers have incised through the plateau, creating gorges that reach up to 1.5 km in depth. The plateau uplifted to its current elevation and was subsequently incised sometime after the Oligocene flood basalt event that signaled the arrival of the African Superplume below Kenya and Ethiopia. Due to its size and extent, published climate modeling has indicated that Late Cenozoic plateau formation could have been a driving force in the East African Cenozoic climate changes. Although …

Structural Evolution And Regional Implications Of The Arrowhead Mine Fault Within The Pahranagat Shear Zone, Nevada, Usa, Michael Dennis Evans

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Basin and Range province is characterized by normal faults associated with

extension, but the occurrence of strike-slip faults and the seismic hazard accompanying

them is less understood. One major strike-slip zone, the Pahranagat shear zone (PSZ),

lies in Lincoln County, Nevada and within the boundary zone between northern Basin

and Range (NBR) and central Basin and Range (CBR) sub-provinces. The PSZ is a 20-

25 km long zone of Cenozoic left-lateral faults. The Arrowhead Mine Fault (AMF) is one

of the three major faults in the PSZ. The western AMF and the faults that surround and

abut it are …