Open Access. Powered by Scholars. Published by Universities.®

Tectonics and Structure Commons

Open Access. Powered by Scholars. Published by Universities.®

667 Full-Text Articles 1,265 Authors 162,990 Downloads 78 Institutions

All Articles in Tectonics and Structure

Faceted Search

667 full-text articles. Page 5 of 23.

Spatially Variable Syn- And Post-Orogenic Exhumation Of The Appalachian Mountains From Apatite And Zircon (U-Th)/He Thermochronology, Luke Coughtry Basler 2020 Bowdoin College

Spatially Variable Syn- And Post-Orogenic Exhumation Of The Appalachian Mountains From Apatite And Zircon (U-Th)/He Thermochronology, Luke Coughtry Basler

Honors Projects

We present zircon and apatite (U-Th)/He (ZHe, closure temperature = 150-200ºC; AHe, closure temperature = 45-80ºC) results from two study regions in the Appalachians Mountains to investigate the timing, rates, and spatial trends of exhumation during Alleghanian orogenesis, Atlantic rifting, and post-rift passive margin conditions. Within West Virginia and Virginia, 10 ZHe dates along an across-orogen transect display an eastward younging trend, from ~425 million years (Ma) in the western Appalachian Plateau province, to ~250-300 Ma in the central Valley-Ridge fold-thrust belt, and 163 ± 29 Ma in the eastern Piedmont. Inverse thermal modeling of ZHe data using external geologic …


Documenting The Earthquake History Of The Thousand Springs Fault In Summer Lake Basin, Oregon, Usa, Elizabeth Curtiss 2020 Central Washington University

Documenting The Earthquake History Of The Thousand Springs Fault In Summer Lake Basin, Oregon, Usa, Elizabeth Curtiss

All Master's Theses

Defining seismic hazards in low-strain-rate regions such as the northwestern Basin and Range can be difficult due to the infrequency of earthquakes. Revealing the earthquake records of low-strain-rate regions can refine our understanding of the variability of earthquake sizes and recurrence intervals, however, which can ultimately improve hazard analysis. Four active normal faults form the Summer Lake basin, in the northwestern Basin and Range: The Thousand Springs (TSF), Ana River (ARF), Slide Mountain, and Winter Ridge faults. Other than the TSF, the faults in the Summer Lake basin have documented histories that include surface-rupturing (>M6) earthquakes. Scarps along the …


Mapping And Modeling The Seattle Fault Tsunami Inundation In Puget Sound, David Bruce 2020 Central Washington University

Mapping And Modeling The Seattle Fault Tsunami Inundation In Puget Sound, David Bruce

All Master's Theses

Coastal communities of Puget Sound are susceptible to tsunami inundation from multiple sources. Two sources of potential tsunami hazard that threaten the region are earthquakes on crustal faults in the Puget Lowlands, or earthquakes originating on the Cascadia subduction zone. This study investigated two coastal marshes in Puget Sound, Deer Lagoon and Doe-Kag-Wats, for evidence of a paleotsunami record to combine with tsunami modeling, in order to predict how future events could inundate Puget Sound. A deposit, interpreted as a paleotsunami, is traceable thought the marsh stratigraphy near the modern day tidal inlet of Deer Lagoon, a site that has …


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 2020 Central Washington University

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 …


Reconstruction Of The 2018 Anak Krakatau Collapse Using Planetscope Imaging And Numerical Modeling, Davide Saviano 2020 Michigan Technological University

Reconstruction Of The 2018 Anak Krakatau Collapse Using Planetscope Imaging And Numerical Modeling, Davide Saviano

Dissertations, Master's Theses and Master's Reports

The study was focused on the Anak Krakatau sector collapse that occurred on 22 December 2018 in the Sunda Strait (Indonesia). The goal of the study was to monitor and analyze changes of the volcanic edifice and to try to understand causes that may have predisposed and triggered the sector collapse.

The use of different remote sensing techniques allowed the acquisition of thermal data, SO2 emission data, structural data and the identification and analysis of the eruptive events that occurred on Anak Krakatau in the period from 1° January 2016 to 28 February 2019. The acquisition of 1221 thermal …


Major Lower Paleozoic Horizons Of The Southern Illinois Basin, John B. Hickman 2019 University of Kentucky

Major Lower Paleozoic Horizons Of The Southern Illinois Basin, John B. Hickman

Kentucky Geological Survey Report of Investigations

The geology exposed at the surface in the southern Illinois Basin has been mapped in great detail by countless workers over the past century. With the exception of limited and scattered exposures in incised river valleys, the oldest rocks exposed outside of the Jessamine, Nashville, and Ozark Domes surrounding the Illinois Basin are Mississippian in age. Extensive deposits of Cambrian–Devonian sediments occur in the subsurface above crystalline basement in this region, however. All available data for the region were analyzed to produce a single, comprehensive set of interpretations. The data used in this study include 1:24,000-scale geologic quadrangle maps, oil …


Quantification Of Surface Roughness Of Lava Flows On Mars, Carolina Rodriguez Sanchez-Vahamonde 2019 The University of Western Ontario

Quantification Of Surface Roughness Of Lava Flows On Mars, Carolina Rodriguez Sanchez-Vahamonde

Electronic Thesis and Dissertation Repository

Volcanism has played a significant role throughout Mars’ geologic history. Extensive lava flows are widely spread across Mars’ equatorial region, shaping the surface in a very distinct way. In radar images (at the decimeter scale), these flows are bright, which is a typical characteristic of extremely rough, blocky lavas flows seen on Earth. Although the source of the extreme roughness of Martian lava flows is unknown, their surface roughness parameters can be constrained to 1) gain information about Mars’ interior processes, 2) find appropriate analogues on other planetary bodies, and 3) ideally infer the emplacement style of such lavas. Here, …


Crustal Structure Beneath The East Coast Magnetic Anomaly From Seismic Refraction Tomography, Collin C. Brandl 2019 University of New Mexico

Crustal Structure Beneath The East Coast Magnetic Anomaly From Seismic Refraction Tomography, Collin C. Brandl

Earth and Planetary Sciences ETDs

Syn-rift igneous addition is necessary for successful continental breakup. Past investigations of passive margins have focused on strike perpendicular structure, but potential field anomalies indicate that significant crustal variations may be present. Data from 21 ocean bottom seismometers was acquired as part of the Eastern North American Margin Community Seismic Experiment and was used for tomographic inversion to create 2D velocity models of the margin that are representative of crustal structure. Crustal thickness varies along-strike from ~20 km to ~24 km and a high velocity (Vp > 7 km/s) layer is present at the base of the crust above the Moho. …


Paleoseismology Of The Central Garlock Fault In Searles Valley, California, Kyle Pena 2019 California State University, San Bernardino

Paleoseismology Of The Central Garlock Fault In Searles Valley, California, Kyle Pena

Electronic Theses, Projects, and Dissertations

In this study, a paleoseismic trench with limited age constraints that was previously excavated in 1990 across the central Garlock Fault near Christmas Canyon, in Searles Valley, California, was reopened to take advantage of new advances in luminescence dating techniques to investigate potential temporal variability in earthquake recurrence on the Garlock fault and to analyze previously unexposed older earthquake evidence. The trench exposed interbedded alluvial sand and pebble-gravels, with well-sorted, rounded, lacustrine sand from the most recent highstand of pluvial Lake Searles present at the base of the trench. Preliminary findings suggest at least 10 surface rupturing earthquake events occurred …


Improving Earthquake Disaster Models With Post-Event Data: Insights From The 2015 Gorkha, Nepal Earthquake, Bradley Steven Wilson 2019 University of Arkansas, Fayetteville

Improving Earthquake Disaster Models With Post-Event Data: Insights From The 2015 Gorkha, Nepal Earthquake, Bradley Steven Wilson

Graduate Theses and Dissertations

Immense amounts of data are collected following earthquake disasters. Yet, it remains unclear how researchers’ might take full advantage of diverse post-disaster datasets. Using data from the 2015 Gorkha Nepal earthquake, this dissertation explores three ways in which post- disaster survey and assessment datasets can be used to inform models of seismic risk, vulnerability, and recovery processes. The first article presents an empirical analysis of scale issues in disaster vulnerability indices using a novel dataset of 750,000 households. This study finds that using aggregated household data to create social vulnerability indices can produce results that are meaningfully different from equivalent …


Reinterpreting The Tectonic Model Of The Southern Part Of The Taconic Orogeny Through A Provenance Study Of Late Ordovician Sandstones, Juan Carlos Guerrero 2019 Louisiana State University and Agricultural and Mechanical College

Reinterpreting The Tectonic Model Of The Southern Part Of The Taconic Orogeny Through A Provenance Study Of Late Ordovician Sandstones, Juan Carlos Guerrero

LSU Master's Theses

A provenance study of quartz arenites that stratigraphically are closely associated with major Ordovician K-bentonites has been conducted in order to further our understanding of the tectonic setting of eastern Laurentia during the Late Ordovician. Using laser ablation ICP-MS, detrital zircons separated from Ordovician sandstone samples in the southeastern Appalachian Mountains (Virginia to Alabama) were dated using U-Pb geochronology. Analytical results show three dominate age ranges for the zircons from these sandstones: ~440-490 Ma, ~900-1300 Ma, and ~1300-1500 Ma. In addition, some zircon ages grouped into older ranges of ~1600-1800 Ma, ~1800-1900 Ma, and ~2600-2800 Ma. Zircon ages from ~900-2800 …


Statistical Modeling And Characterization Of Induced Seismicity Within The Western Canada Sedimentary Basin, Sid Kothari 2019 The University of Western Ontario

Statistical Modeling And Characterization Of Induced Seismicity Within The Western Canada Sedimentary Basin, Sid Kothari

Electronic Thesis and Dissertation Repository

In western Canada, there has been an increase in seismic activity linked to anthropogenic energy-related operations including conventional hydrocarbon production, wastewater fluid injection and more recently hydraulic fracturing (HF). Statistical modeling and characterization of the space, time and magnitude distributions of the seismicity clusters is vital for a better understanding of induced earthquake processes and development of predictive models. In this work, a statistical analysis of the seismicity in the Western Canada Sedimentary Basin was performed across past and present time periods by utilizing a compiled earthquake catalogue for Alberta and eastern British Columbia. Specifically, the frequency-magnitude statistics were analyzed …


Application Of 3d Salt Modeling: An Example From The Northeastern Gulf Of Mexico, Adam Mattson 2019 Western Kentucky University

Application Of 3d Salt Modeling: An Example From The Northeastern Gulf Of Mexico, Adam Mattson

Masters Theses & Specialist Projects

Salt tectonics has important implications for hydrocarbon exploration in saltbearing basins since salt deformation can directly or indirectly form hydrocarbon traps, influence hydrocarbon migration, and can control deepwater depositional systems. In various basins around the globe, extensive research has been conducted on initiation of salt mobilization, subsequent deformation, and eventual cessation, mostly from subsurface two-dimensional (2D) sections. However, 3D seismic data has dominated the petroleum industry for the last 30 years. Despite the plethora of 3D seismic data acquired in salt-bearing basins, there has been hardly any published work on the 3D geometries of complex salt bodies. 3D salt mapping …


Millard Et Al. Pressure Dependence Of Magnesite Creep 2019 Geosciences.Pdf, Caleb Holyoke 2019 University of Akron

Millard Et Al. Pressure Dependence Of Magnesite Creep 2019 Geosciences.Pdf, Caleb Holyoke

Caleb Holyoke

No abstract provided.


Utilizing Dplot, Sedlog, And Arcgis Pro To Enhance Geologic Field Skills: Rosendale, Ulster County New York, Malek Shami, Nazrul I. Khandaker, Stanley Schleifer, Zarine Ali, Leonardo Sanchez, Gugu Ginindza, Tyn Tyn Nai 2019 CUNY York College

Utilizing Dplot, Sedlog, And Arcgis Pro To Enhance Geologic Field Skills: Rosendale, Ulster County New York, Malek Shami, Nazrul I. Khandaker, Stanley Schleifer, Zarine Ali, Leonardo Sanchez, Gugu Ginindza, Tyn Tyn Nai

Publications and Research

Capstone geologic field mapping courses in undergraduate geoscience programs aim to compliment the academic knowledge with technical field skills. As a pilot study, these tools were used to collect field data using folded lower Paleozoic to mid-Paleozoic sedimentary outcrops consisting of clastic, non-clastic and occasional mixed siliciclastics in Rosendale, Ulster County, New York. Rosendale is known for its classic geological outcrops with variable structural, stratigraphic, paleontological and sedimentological complexities – ideal for a field mapping course. Traditionally, students’ data acquisition in the field and its subsequent laboratory analysis to produce a final geologic field report utilized acetate overlays to produce …


Orientation Of Paleostress Of Raplee Ridge Anticline, Loren Randall Holyoak, John S. MacLean 2019 Southern Utah University

Orientation Of Paleostress Of Raplee Ridge Anticline, Loren Randall Holyoak, John S. Maclean

The Compass: Earth Science Journal of Sigma Gamma Epsilon

During the Laramide Orogeny several major folds were formed in Southern Utah, one of those being the Raplee Ridge anticline. Raplee Ridge is approximately eight miles from Mexican Hat, Utah. The San Juan River cuts through the anticline, exposing the Honaker Trail Formation’s beds of shale and limestone with chert nodules. Accompanying the mountain-scale ductile deformation of the Raplee Ridge anticline are decimeter-scale brittle conjugate fractures in the limestone’s chert nodules. The objective of this study is to compare the orientation of paleostress that formed the Raplee Ridge anticline with the conjugate fractures within the chert nodules to see if …


Gamma Ray And Radon Anomalies In Northern Taiwan As A Possible Preearthquake Indicator Around The Plate Boundary, Ching-Chou Fu, Lou-Chuang Lee, Tsanyao Frank Yang, Cheng-Horng Lin, Cheng-Hong Chen, Vivek Walia, Tsung-Kwei Liu, Dimitar Ouzounov, Gioacchino Giuliani, Tzu-Hua Lai, Peng-Kang Wang 2019 Academia Sinica

Gamma Ray And Radon Anomalies In Northern Taiwan As A Possible Preearthquake Indicator Around The Plate Boundary, Ching-Chou Fu, Lou-Chuang Lee, Tsanyao Frank Yang, Cheng-Horng Lin, Cheng-Hong Chen, Vivek Walia, Tsung-Kwei Liu, Dimitar Ouzounov, Gioacchino Giuliani, Tzu-Hua Lai, Peng-Kang Wang

Mathematics, Physics, and Computer Science Faculty Articles and Research

Taiwan is tectonically situated in an oblique collision zone between the Philippine Sea Plate (PSP) and the Eurasian Plate (EP). Continuous observations of gamma rays at the Yangmingshan (YMSG) station and soil radon at the Tapingti (TPT) station were recorded in the volcanic area and around a major fault zone, respectively, in Taiwan for seismic studies. A number of anomalous high gamma ray counts and radon concentrations at certain times were found. It is noted that significant increases of soil radon concentrations were observed and followed by the increase in gamma rays a few days to a few weeks before …


Fractures, Fluids, And Metamorphism: Shear Zone Initiation In The Marcy Anorthosite Massif, Adirondacks, New York, Usa, James Hodge 2019 University of Maine

Fractures, Fluids, And Metamorphism: Shear Zone Initiation In The Marcy Anorthosite Massif, Adirondacks, New York, Usa, James Hodge

Electronic Theses and Dissertations

Localized shear zones are important rheological features that influence deformation behavior throughout the Earth’s middle-to-lower crust. Therefore, the processes through which shear zones initiate and localize remains an important geologic question. The study of strain localization and shear zone initiation is made difficult due to continued deformation overprinting the microstructures which lead to initiation and obfuscating the context in which localization occurred. The Marcy anorthosite in the Adirondack Highlands, New York, is a nominally granulite-facies, plagioclase-rich massif cut by centimeter-to-meter scale shear zones which provides a natural example of shear zone localization within the middle-to-lower crust. My work focuses on …


Machine Learning Predicts Aperiodic Laboratory Earthquakes, Olha Tanyuk, Daniel Davieau, Charles South, Daniel W. Engels 2019 Southern Methodist University

Machine Learning Predicts Aperiodic Laboratory Earthquakes, Olha Tanyuk, Daniel Davieau, Charles South, Daniel W. Engels

SMU Data Science Review

In this paper we find a pattern of aperiodic seismic signals that precede earthquakes at any time in a laboratory earthquake’s cycle using a small window of time. We use a data set that comes from a classic laboratory experiment having several stick-slip displacements (earthquakes), a type of experiment which has been studied as a simulation of seismologic faults for decades. This data exhibits similar behavior to natural earthquakes, so the same approach may work in predicting the timing of them. Here we show that by applying random forest machine learning technique to the acoustic signal emitted by a laboratory …


In-Situ Zircon And Monazite Geochronology From Compositionally Distinct Layers In A Single Migmatitic Paragneiss Sample Located In The Eastern Adirondack Mountains, Ny, Kaitlyn Suarez 2019 University of Massachusetts Amherst

In-Situ Zircon And Monazite Geochronology From Compositionally Distinct Layers In A Single Migmatitic Paragneiss Sample Located In The Eastern Adirondack Mountains, Ny, Kaitlyn Suarez

Masters Theses

Migmatites are a common rock type in the Adirondack Mountains, NY. We analyzed a single sample of biotite-garnet-sillimanite paragneiss with foliation parallel leucosome along Route 22 south of Whitehall, NY in order to determine the timing of melting using both in-situ monazite and zircon U/Pb geochronology from the restite and leucosome layers of the same rock. Monazite was analyzed via in-situ EMPA on the Ultrachron microprobe at the University of Massachusetts. Zircon was analyzed via LA-ICP-MS (in-situ and mounted mineral separates) at the LaserChron Center. Monazite analyses from the restite yielded six compositionally distinct populations with dates of 1178 ± …


Digital Commons powered by bepress