Geology Commons^™

Holocene Sedimentary Responses To Growth Faulting In A Back-Barrier Setting: East Matagorda Peninsula, Texas, Phillip Wolfe

Theses and Dissertations--Earth and Environmental Sciences

The structural framework of the northern Gulf of Mexico coastal zone is characterized by numerous growth fault systems. Neotectonic processes in coastal marshes in this region have been shown to be important drivers of relative sea-level rise as well as having significant influence on marsh accretion processes. One active growth fault has been identified at East Matagorda Peninsula, Texas. To characterize the Holocene behavior of this fault and the consequent sedimentary responses, a suite of fallout radionuclides (⁷Be, ¹³⁷Cs, ²¹⁰Pb) and radiocarbon, supplemented by sediment physical property data have been used to determine sediment mixing depths, …

A Petrographic Characterization Of The Leatherwood Coal Bed In Eastern Kentucky, Michelle N. Johnston

Theses and Dissertations--Earth and Environmental Sciences

The Eastern Kentucky Coal Field is located in the central portion of the Appalachian Basin. The Pennsylvanian Breathitt Formation in this region is characterized by numerous sequences of bituminous coal-bearing sedimentary rocks. These coals have distinct maceral compositions due to variations in depositional environments. Coal characterization is an important method for determining conditions that influenced peat accumulation and overall depositional settings of mires.

This study focuses on the characterization of the maceral composition of the Middle Pennsylvanian-age Leatherwood coal bed. It utilizes petrographical, palynological, and geochemical analyses to describe specific depositional environments and associated peat accumulation conditions.

Petrographic analyses indicate …

Age Of The Walden Creek Group, Western Blue Ridge Province: Resolving A Decades-Old Controversy Via Detrital Mineral Geochronology And Sedimentary Provenance Analysis, Evan A. Kelly

Theses and Dissertations--Earth and Environmental Sciences

Originally mapped as Precambrian and uppermost Ocoee Supergroup (OS), recent discoveries of Paleozoic microfossils have placed the Walden Creek Group (WCG), eastern Tennessee, into a younger depositional framework (Silurian or younger). In this study, monazite geochronology using SIMs, detrital zircon U-Pb geochronology determined by LA-ICP-MS, feldspar compositions determined by microprobe, zircon-tourmaline-rutile (ZTR) indices, and framework mineral modes were used to characterize provenance of sandstones of the WCG. Monazite ages cluster at 450 and 1050 Ma. All Ordovician ages are from grains that, in BSE images, have inclusion-rich microtextures interpreted as diagenetic and/or metamorphic, thus requiring that the WCG was deposited …

The Nature And Origin Of Cyclicity In The Cleveland Member Of The Ohio Shale (Upper Devonian), Northeastern Kentucky, U.S.A., Alice C. O'Bryan

Theses and Dissertations--Earth and Environmental Sciences

The Cleveland Shale displays a characteristic and distinctive pattern of promontories and recessed intervals on weathered outcrops, which appears to represent cyclicity. This weathering pattern can be observed in other shales, both within and outside the Appalachian Basin; so determining the nature of these cycles may be critical for understanding the origin of, not only the Cleveland Shale, but also of black shales in general. Cyclicity in the Cleveland was examined on a decimeter-to-meter scale using lithologic characterization, gamma-ray stratigraphy and x-ray fluorescence, and on a millimeter-to-centimeter scale using organic petrography. Lithologic characterization and gamma-ray stratigraphy revealed Milankovitch-band fourth- and …

Paleoseismic And Structural Characterization Of The Hines Creek Fault: Denali National Park And Preserve, Alaska, Sara E. Federschmidt

Theses and Dissertations--Earth and Environmental Sciences

The Hines Creek fault (HCF) is a Holocene-active fault in central Alaska. Its trace has been mapped several times, but data on the history of fault displacement is scarce. As a major crustal-scale geologic boundary with uncertain Quaternary tectonic activity, it is a priority for more to be known about the activity of this fault to better understand the hazards it presents to the Denali National Park and Preserve and Alaskan infrastructure. This study characterizes the late Quaternary activity of the HCF through surficial geologic mapping and paleoseismic investigations. Mapping revealed a very steep (~84°-88° apparent dip), north dipping fault …

Instrument Correction And Dynamic Site Profile Validation At The Central United States Seismic Observatory, New Madrid Seismic Zone, Clayton M.J. Brengman

Theses and Dissertations--Earth and Environmental Sciences

The Central United States Seismic Observatory (CUSSO), is a fifteen-element array of three-component accelerometers and seismometers in the New Madrid seismic zone, within the upper Mississippi embayment. Its location within the thick (up to 1 km) sequences of unlithified sediment comprising the embayment, make CUSSO a unique array in its ability to directly measure seismic wave propagation, including ground motion site effect; however, before the observational data can be used for analysis, the orientation and instrument response of the CUSSO array must be defined. This study used cross-correlation and direct comparisons to filter out the instrument response and determine the …

Application Of The Kalman Filter On Full Tensor Gravity Gradiometry Data Around The Vinton Salt Dome, Louisiana, Mahnaz Sepehrmanesh

Theses and Dissertations--Earth and Environmental Sciences

Full tensor gravity (FTG) data are known for their high resolution but also for higher noise in its components due to the dynamic nature of the platform used for data acquisition. Although a review of the literature suggests steady increase in the success of gravity gradiometry, we still cannot take advantage of the full potential of the method, mostly because of the noise with the same amplitude and wavenumber characteristics as the signal that affects these data. Smoothing from common low pass filters removes small wavelength features and makes it difficult to detect structural features and other density variations of …

Geology Of The West Half Of The Cove Creek Gap Quadrangle And Adjacent Areas, Western North Carolina: Insights Into Eastern Great Smoky Mountains Tectonometamorphism, Daniel F. Spaulding

Theses and Dissertations--Earth and Environmental Sciences

Three outstanding problems related to the tectonic evolution of the Western Blue Ridge in the eastern Great Smoky Mtns. (GSM) include: (1) the nature of the Greenbrier Fault, previously interpreted as a younger over older pre-Taconic thrust fault with ~24 km of displacement between the Snowbird and Great Smoky Groups; (2) the relationship of regional metamorphism, expressed by the growth of porphyroblastic index minerals, to folding and foliation development in pelitic metasediments; (3) the relation of deformation to regional Taconian metamorphism. These problems were addressed in previous studies that did not have detailed mapping and petrography as a context. By …

From Geology To Art History: Ceramist Alexandre Brongniart’S Overlooked Contribution To The Developing Science Of Art History In The Early Nineteenth Century, Julia A. Carr-Trebelhorn

Theses and Dissertations--Art and Visual Studies

Alexandre Brongniart was known for his work as an important geologist and as an administrator at the Sèvres Porcelain Manufactory, but his roles as art historian and museologist are overlooked. Brongniart created a holistic methodology taken directly from science and applied it to ceramic art of all cultures and eras. He had a uniquely modern perspective on time, world culture, and archeology. Brongniart wrote about the art of Asia and the Americas on an equal status with that of the Classical West at least fifty years before it became a mainstream idea. Brongniart integrated scientific principle and practice into the …

Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu

Department of Earth, Environment and Sustainability Faculty Publications

Reconstruction of the Hirnantian (Late Ordovician) palaeotopography in South China is important for understanding the distribution pattern of the Hirnantian marine depositional environment. In this study, we reconstructed the Hirnantian palaeotopography in the Upper Yangtze region based on the rankings of the palaeo-water depths, which were inferred according to the lithofacies and biofacies characteristics of the sections. Data from 374 Hirnantian sections were collected and standardized through the online Geobiodiversity Database. The Ordinary Kriging interpolation method in the ArcGIS software was applied to create the continuous surface of the palaeo-water depths, i.e. the Hirnantian palaeotopography. Meanwhile, the line transect analysis …

The Depositional Environment And Diagenetic Effects On Sand Bodies Within The Unconventional Resource Play Of The Spearfish Formation (Triassic) In North Central North Dakota, Matthew J. Sebade

Theses and Dissertations

The Triassic Spearfish Formation in North Dakota is comprised of three members, the Belfield, Pine, and Saude Members, in ascending order. This study focuses on the Saude Member in north-central North Dakota on the eastern margin of the Williston basin. Both the upper and lower contacts of the Spearfish in the study area are unconformable. In this region, the lateral distribution of red sandstone and argillaceous siltstone lithofacies were mapped using well log data. Four sandstone bodies were identified then mapped across the region using gamma ray logs. Sandstone bodies in descending order are the A sand, B sand, water …

How Unusual Is Tropical Storm Irene? A Case Study Of Storm Deposition In Littleville Lake, Huntington, Ma, Catherine Dunn

Honors Papers

Tropical Storm Irene hit the northeastern United States in August 2011 with impressive rates of precipitation and river discharge. However, it was the combination of this heavy rain with high antecedent soil moisture that made Irene so unusual. The Connecticut River had a particularly high sediment yield after the storm, with a sediment concentration over 1,000 mg/L at the mouth of the river. Littleville Lake on the Westfield River was selected as a study site because of its flood control feature, which allows for the calculation of trapping efficiency in dammed rivers. Coring in the lake showed that there was …

Full Of Hot Air: Heat Flow At The Medicine Lake Volcano Hot Spot, Modoc County, California, Katrina D. Gelwick

Honors Papers

Changes in volcanic hydrothermal systems can shed light on the physical processes associated with volcanic unrest such as changes in an underlying magma body. The U.S. Geological Survey recently implemented an experimental hydrothermal monitoring network throughout the Cascade volcanic arc. Despite being ranked as the 12th highest threat among all Cascade volcanoes, Medicine Lake Volcano in northeastern California is considered under-monitored. The primary hydrothermal-monitoring site at Medicine Lake Volcano is a weak fumarole contained within a small area of heated ground, called the Hot Spot, located near the caldera rim. This study uses data from a survey conducted in August …

The Effect Of Rainfall And Post-Revolutionary Land-Use Changes On Sediment Yield In Weixi Basin, Yunnan, China : New Insights From Multi-Temporal Land-Use Classification And Radionuclide Analyses, Yue Qiu

Honors Papers

This paper looks at the dynamic interphase connecting post-revolutionary politics, modern land use practices, precipitation patterns, basin slope, and sediment yield records in Weixi basin, a small mountainous watershed in Southwestern China with a total upstream area of 198 m2. The goal is to identify what processes, climatic or not, account for the changes in local sediment yield and erosion budget. Weixi basin has an average annual sediment yield of 175 ton/km2 with two anomalously large peaks in 1979 and 1984. Precipitation is moderately correlated with sediment yield at interannual scale. It also affects seasonal fluctuations in sediment yield as …

Deformation And Exhumation Across Gianbul Dome, Nw India: Insight From Deformation Kinematics And Temperatures, And 40ar/39ar Thermochronology, Meilani Bowman-Kamaha’O

All Master's Theses

New kinematic, microtextural, and thermochronology studies test the hypothesis that high temperature-moderate pressure rocks exposed in Gianbul Dome, NW India, were exhumed south of the southern Tibetan detachment system by the southward extrusion of a mid-crustal ductile channel. Mesoscopic and microscopic kinematic indicators record normal-sense shear in the Khanjar and Zanskar shear zones, which define the southwest and northeast flanks of Gianbul Dome, respectively. Microtextural analyses indicate deformation at >400°C along dome flanks increasing to > 700°C in the core. Moderate temperature cooling is asymmetric across the dome, initiating at ~22 Ma on the southwest flank of the dome-and at ~20 …

Constraints On Interplate Locking Within The Makran Subduction Zone Using Gps, Elyse Erin Frohling

All Master's Theses

We use GPS measurements from 20 stations located in Iran, Pakistan, and Oman along with International Seismological Centre hypocentral locations to create a fault coupling model for the Makran subduction zone. The 3-D geometry of the megathrust fault is estimated from five profiles landward of the Makran trench. Continuous GPS on the Arabian plate show convergence of ~27 mm/year, and interseismic deformation is calculated using the back-slip method of Savage [ 1983]. We find the entire subduction zone appears to be accumulating stress uniformly from ~15-60 km depth and find no evidence of along-strike segmentation in strain accumulation, suggesting the …

Structural Deformation Across The Southwest Mina Deflection, California-Nevada: Field Studies In The Huntoon Spring Quadrangle, Eliya R. Hogan

All Master's Theses

New geologic data provides insight into Pliocene strain rates across the southwest Mina deflection. ⁴⁰ Ar/³⁹ Ar geochronology of geologic units indicate cooling of Miocene ignimbrite at 11.86 ± 0.01 Ma, Pliocene basalt lavas at 3.7241 ± 0.0051 and 3.5262 ± 0.0172 Ma, and basaltic andesite and andesite lavas at 3.4715 ± 0.0107 Ma and 3.1078 ± 0.0088 Ma. Pliocene cinder cones and Quaternary sediments are also exposed in the Huntoon Spring quadrangle. Volcanic units are cut by a dominant set of NNE-, NE-, and ENE- striking sinistral faults and a lesser set of NNW- and NW- striking normal …

Classification Of Four Meteorite Samples, Karla Farley

University Honors Theses

The petrography, mineralogy, and mineral chemistry of four unclassified Northwest Africa meteorites in the Cascadia Meteorite Laboratory collection (CML0005, 0023, 0024, 0032) were studied using optical microscopy and scanning electron microscopy. The data will be used to classify the meteorites and to obtain official names for the meteorites. CML0023 has the preliminary classification of L6 (S3) W1, CML0024 has L6 (S3) W1, and CML0032 has L6 (S2) W1. CML0005 has chemistry and mineralogy that indicate it is an anomalous acapulcoite.

Benthic And Pelagic Pathways Of Methylmercury Bioaccumulation In Estuarine Food Webs Of The Northeast United States, Celia Y. Chen, Mark E. Borsuk, Deenie M. Bugge, Terill Hollweg

Dartmouth Scholarship

Methylmercury (MeHg) is a contaminant of global concern that bioaccumulates and bioamagnifies in marine food webs. Lower trophic level fauna are important conduits of MeHg from sediment and water to estuarine and coastal fish harvested for human consumption. However, the sources and pathways of MeHg to these coastal fisheries are poorly known particularly the potential for transfer of MeHg from the sediment to biotic compartments. Across a broad gradient of human land impacts, we analyzed MeHg concentrations in food webs at ten estuarine sites in the Northeast US (from the Hackensack Meadowlands, NJ to the Gulf of Maine). MeHg concentrations …

Relationship Between Static Stress Change And Volcanism. How And If Tectonic Earthquake Could Influence Volcanic Activity. Example Of El Reventador Volcano, Ecuador, Daniele Alami

Dissertations, Master's Theses and Master's Reports - Open

No abstract provided.