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The Origin Of An Archean Batholith In Michigan’S Upper Peninsula, Brandi Petryk 2019 Michigan Technological University

The Origin Of An Archean Batholith In Michigan’S Upper Peninsula, Brandi Petryk

Dissertations, Master's Theses and Master's Reports

The Southern Complex is part of the Archean Superior Province in the Upper Peninsula of Michigan and includes a batholithic sized body of Archean high-K megacrystic granitoid rocks informally called the Bell Creek granite. U-Pb zircon ages of the granitoid from previous studies suggest an emplacement age of ~2.6 Ga (Tinkham, 1997). Based on those ages the Bell Creek granite formed around the Archean-Proterozoic transition. This transition is a crucial time period in Earth’s history for crustal growth because of the onset of subduction and increased sedimentary environments at the end of the Archean (Taylor and McLennan, 1995). In this …


Spatial And Temporal Analysis Of The 27 April 2011 Tornado Outbreak In Central Alabama, Whitney Flynn, Tanveer Islam 2019 National Oceanic and Atmospheric Administration

Spatial And Temporal Analysis Of The 27 April 2011 Tornado Outbreak In Central Alabama, Whitney Flynn, Tanveer Islam

Research, Publications & Creative Work

This study investigates the spatial and temporal patterns of the 27 April 2011 tornado outbreak in Central Alabama. Disasters, and vulnerabilities to such events, vary across space and time. The 2011 Super Outbreak was the largest, most costly, and one of the most deadly tornado outbreaks ever recorded in U.S. history. In this study, the results of 29 documented tornado tracks (889 data points total) in Central Alabama reveal findings related to complex topography and its effects on tornado intensity. The temporal pattern s of this particular outbreak are - consistent with other studies’ evidence that suggests a small peak …


Response Of Vegetation In Open And Partially Wooded Fens To Prescribed Burning At Seney National Wildlife Refuge, Jane E. Austin, Wesley E. Newton 2019 U.S. Department of the Interior & U.S. Geological Survey

Response Of Vegetation In Open And Partially Wooded Fens To Prescribed Burning At Seney National Wildlife Refuge, Jane E. Austin, Wesley E. Newton

United States Geological Survey: Publications

The health and function of northern peatlands, particularly for fens, are strongly affected by fire and hydrology. Fens are important to several avian species of conservation interest, notably the yellow rail (Coturnicops noveboracensis). Fire suppression and altered hydrology often result in woody encroachment, altering the plant community and structure. Woody encroachment and its effects on biodiversity have become an increasing concern in the conservation and management of plant communities. This study evaluated the effects of spring and summer prescribed burns on the plant community, cover, and structure in open and partially wooded fens at Seney National Wildlife Refuge, Michigan, using …


Coastal Wetlands: A Synthesis, Charles S. Hopkinson, Eric Wolanski, Mark M. Brinson, Donald R. Cahoon, Gerardo M.E. Perillo 2019 University of Georgia, Athens

Coastal Wetlands: A Synthesis, Charles S. Hopkinson, Eric Wolanski, Mark M. Brinson, Donald R. Cahoon, Gerardo M.E. Perillo

United States Geological Survey: Staff Publications

What are coastal wetland ecosystems, what are their limits of distribution, and where do they exist in the overall coastal landscape? There are several general definitions for wetlands, but the Ramsar definition is likely the most broadly encompassing (http://www.ramsar. org/), whereas others are more focused definitions tailored to country-specific protection and management policies (Mitsch and Gosselink, 2006). We offer a very general approach rather than a precise definition: coastal wetlands are ecosystems that are found within an elevation gradient that ranges between subtidal depths where light penetrates to support photosynthesis of benthic plants to the landward edge where the sea …


Interpreting Vegetation And Soil Anomalies In The Guarumen Area Of Northwestern Venezuela Using Remote Sensing Applications, Tyler Edward Ricketts 2019 University of Mississippi

Interpreting Vegetation And Soil Anomalies In The Guarumen Area Of Northwestern Venezuela Using Remote Sensing Applications, Tyler Edward Ricketts

Electronic Theses and Dissertations

The Guarumen area of Venezuela is a tectonically active region that is approximately 1,640 mi2 across the northern portions of the Barinas Basin and the foothills of the Mérida Andes. It is structurally influenced by the Caribbean plate to the north, the Nazca plate to the west, and the Maracaibo block against the Guyana Shield of the South American Plate. These result in an oblique boundary that gives rise to the fold-and-thrust belt of the Mérida Andes to the west, and the Caribbean Mountain system to the north, in concordance to the right-lateral shearing that is evidenced by the Boconó …


Provenance, Redox Conditions, And Diagenesis Of Shales In Chang 7 Member Of Upper Triassic Yanchang Formation, Ordos Basin, China, Bin Sun 2019 Missouri University of Science and Technology

Provenance, Redox Conditions, And Diagenesis Of Shales In Chang 7 Member Of Upper Triassic Yanchang Formation, Ordos Basin, China, Bin Sun

Doctoral Dissertations

“This study aims to decipher provenance, redox conditions, and burial history of shales in Chang 7 Member of Upper Triassic Yanchang Formation, Ordos Basin, China. The first paper discusses the origins of single-channeled, vertical, sinuous, and calcite-bitumen-filled cracks in the shales. Results show that in early diagenesis, unconsolidated mud was expanded open by escaping gases produced during organic matter maturation under hydrothermal influences. Calcite initially filled the cracks; bitumen and pyrite came in later and occupied the cracks in various ways. Compaction occurred next and folded the calcite- and bitumen-filled cracks into sinuous shapes. The second paper uses geochemical and …


Origin Of Periclines In The Ozark Plateau, Missouri: A Field And Numerical Modeling, Chao Liu 2019 Missouri University of Science and Technology

Origin Of Periclines In The Ozark Plateau, Missouri: A Field And Numerical Modeling, Chao Liu

Doctoral Dissertations

"A series upright sub-horizontal folds in sandstones of the early Ordovician Roubidoux Formation are exposed in road cuts along US Highway 63 in the northern part of the Salem Plateau of central Missouri for over a distance of approximately 10 km. These folds are in marked contrast to the more typical horizontal to sub-horizontal Ordovician strata of the Ozark Plateau. The origin of those folds remains enigmatic. The inspection of the characteristics of these folds using stereographic analysis revealed a non-cylindrical geometrical pattern than a near cylindrical fold. Structural data of 54 folds indicate an alternating basin and dome pattern. …


Seismic Attribute Assisted Depositional Facies Identification And Stratigraphic Correlation In The Central Gulf Coast Region Of Texas, Yani Lin 2019 Missouri University of Science and Technology

Seismic Attribute Assisted Depositional Facies Identification And Stratigraphic Correlation In The Central Gulf Coast Region Of Texas, Yani Lin

Doctoral Dissertations

"The sandstone deposits in the fluvial-dominated delta systems in the Lower Wilcox Group above the Cretaceous carbonate shelf edges of the Texas Gulf Coast Region are considered as high exploration potential reservoir bodies. However, the multi-phase regression and transgression during the late Paleocene to the early Eocene complicate the local depositional structure. The depositional facies is hard to be identified in details using the traditional seismic stratigraphic interpretation method. Seismic attributes are effective in detecting depositional facies, especially in mapping channels and investigating reservoir characteristics. In this study, we utilize seismic attributes to identify the principal depositional facies in the …


U-Pb Detrital Zircon Geochronology Of Paleozoic Clastics Of The Ozark Plateau: Implication For Sea-Level Fluctuations And Far-Field Tectonics, Chen Zhao 2019 Missouri University of Science and Technology

U-Pb Detrital Zircon Geochronology Of Paleozoic Clastics Of The Ozark Plateau: Implication For Sea-Level Fluctuations And Far-Field Tectonics, Chen Zhao

Masters Theses

"The Ozark Plateau of south-central Missouri is underlain by Ordovician to Pennsylvanian carbonate and clastic strata. Enigmatic, presumably Pennsylvanian 'filled sink' structures are common on the Ozark Plateau and remain a source of controversy. We present results for U-Pb ages of detrital zircons for 13 samples from the OP. We use U-Pb ages from other Paleozoic clastics and 'filled sinks' on the OP, to suggest: 1) FSS record a period of Middle Ordovician erosion and sedimentation and 2) document significant shifts in sediment provenance that reflect regional tectonic events affecting the North American Craton.

The KDE plots of normalized detrital …


Structural Style And Stratigraphic Architecture Of The Northeastern Brooks Range, Alaska, Benjamin G. Johnson 2019 West Virginia University

Structural Style And Stratigraphic Architecture Of The Northeastern Brooks Range, Alaska, Benjamin G. Johnson

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Arctic Alaska–Chukotka microplate is a large Mesozoic–Cenozoic composite terrane that resides at the northern limit of the North American Cordillera. Although its Mesozoic origins are assuredly linked to the opening of the Amerasian Basin of the Arctic Ocean, its Paleozoic origins can be linked to at least three separate paleocontinents, including northern Laurentia, Baltica, and Siberia. Across the Arctic Alaska portion of the microplate, an internal, mid-Paleozoic suture zone presumably separates rocks of the North Slope subterrane (Laurentian affinity) from a collection of smaller subterranes in the southern Brooks Range and Seward Peninsula (Baltic affinity).

The mountains of the …


Utilizing Lipid Biomarkers To Understand The Microbial Community Structure Of Deep Subsurface Black Shale Formations, Rawlings Akondi 2019 West Virginia University

Utilizing Lipid Biomarkers To Understand The Microbial Community Structure Of Deep Subsurface Black Shale Formations, Rawlings Akondi

Graduate Theses, Dissertations, and Problem Reports (ETD)

The deep subsurface environment has been known to host microbes as early as 1926 and has also been suggested to potentially account for as much as 50% of the Earth`s biomass. Researchers have shown that microbes alter their membrane lipid components in response to physiological stress, producing stress indicative lipid biomarkers. However, little effort has been made to understand the subsurface microbial community of the shale ecosystem which is increasingly being exploited and altered by addition of drilling and hydraulic fluids to meet our growing energy needs. Phospholipid fatty acids (PLFAs) are microbial lipid biomarkers and are found in all …


Application Of Lidar To 3d Structural Mapping, Bertrand Gaschot 2019 West Virginia University

Application Of Lidar To 3d Structural Mapping, Bertrand Gaschot

Graduate Theses, Dissertations, and Problem Reports (ETD)

The rugged, densely forested terrain of the West Virginia Appalachian Valley and Ridge Province has made it difficult for field-based studies to agree on the structure of the highly deformed Silurian-Devonian cover strata. In this study, we demonstrate a 3D approach to geologic mapping utilizing the structural information revealed in a “bare-earth” 1-m Lidar DEM of the Smoke Hole Canyon. The completed 3D map was integrated with kinematic forward modeling carried out in MOVETM to provide information on the parameters required to form the major structures observed. Additionally, land surface attributes generated using geomorphometric analysis of the Lidar allowed …


Analyzing The Relationship Between Reconstruction And The Socio Economic Regions In Post Katrina New Orleans, Adrienne Swindle, Lisa Keys-Mathews 2019 University of North Alabama

Analyzing The Relationship Between Reconstruction And The Socio Economic Regions In Post Katrina New Orleans, Adrienne Swindle, Lisa Keys-Mathews

Geography

No abstract provided.


Optimum Moisture Content And Maximum Dry Unit Weight For Compaction Of Interdisciplinary Science Center Soil, Rachel A. Lunstroth, Maria Camilla O'Toole, Melissa Simbler 2019 Eastern Washington University

Optimum Moisture Content And Maximum Dry Unit Weight For Compaction Of Interdisciplinary Science Center Soil, Rachel A. Lunstroth, Maria Camilla O'Toole, Melissa Simbler

2019 Symposium

Eastern Washington University’s is currently undergoing construction with the addition of the Interdisciplinary Science Center. A soil sample was collected from the construction site and over the course of Fall Quarter 2018 we performed a series of tests on this soil allowing us to classify the soil based on the Unified Soil Classification System. These tests include: a specific gravity determination test according to the American Society for Testing and Materials (ASTM) standard D854, a sieve and hydrometer analysis according to the ASTM standard D422, and an Atterberg limits test according to the ASTM standard D-4318. We also performed a …


Stratigraphic And Structural Characterization And Evolution Of Exposed Megaflaps Flanking Salt Diapirs, Cora Evelyn Gannaway Dalton 2019 University of Texas at El Paso

Stratigraphic And Structural Characterization And Evolution Of Exposed Megaflaps Flanking Salt Diapirs, Cora Evelyn Gannaway Dalton

Open Access Theses & Dissertations

A Neoproterozoic salt system exposed in the Willouran Ranges of South Australia and a Mesozoic salt system in the south-central Pyrenees of Spain provide natural laboratories to investigate the stratigraphic and structural development of megaflaps flanking salt diapirs. Megaflaps are near-vertical to overturned, deep minibasin stratal panels that extend far up the flanks of steep diapirs or their equivalent welds. Megaflaps can form by halokinetic drape-folding, contraction, or a combination of these processes. The existing models of megaflap development are based primarily on seismic data, well penetrations, cross-section restorations, and numerical and analog modeling. Investigation of the sedimentology, stratigraphy, and …


Geology Of Southeastern Nebraska, Robert Matthew Joeckel, Dana Divine, Leslie M. Howard, Kathleen Cameron, Michele M. Waszgis 2019 University of Nebraska - Lincoln

Geology Of Southeastern Nebraska, Robert Matthew Joeckel, Dana Divine, Leslie M. Howard, Kathleen Cameron, Michele M. Waszgis

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Paleomagnetic Investigation Of Igneous Rocks Deformed By The Keweenaw Fault In The Northwestern Keweenaw Peninsula., Daniel Trekas 2019 Michigan Technological University

Paleomagnetic Investigation Of Igneous Rocks Deformed By The Keweenaw Fault In The Northwestern Keweenaw Peninsula., Daniel Trekas

Dissertations, Master's Theses and Master's Reports

One of the most prominent structural features associated with the ~1.1 Ga Midcontinent Rift (MCR) system is the >350 km long Keweenaw Fault that bisects the Keweenaw Peninsula, separating the MCR-related Portage Lake Volcanics (PLV) and the younger Jacobsville Sandstone (JS). The fault trend is NE-NNE over most of its length, but changes to an easterly direction along the shore of Bête Grise Bay near the end of the peninsula. Conventionally, the Keweenaw Fault has been considered to be a continuous reverse (dip-slip) fault formed by inversion of an original rift-bounding normal fault during the Grenville Orogeny. However, recent mapping …


The Medicine Hat Block And The Assembly Of Laurentia: New Interpretations From Single-Grain Zircon Analyses, Blake Oswell LaDouceur 2019 University of Mississippi

The Medicine Hat Block And The Assembly Of Laurentia: New Interpretations From Single-Grain Zircon Analyses, Blake Oswell Ladouceur

Electronic Theses and Dissertations

The Medicine Hat Block (MHB) is one of the core cratonic elements that amalgamated in the Paleoproterozoic to form Laurentia. However the role of the MHB in the formation of Laurentia is poorly constrained due to virtually all of the MHB being concealed by Proterozoic and younger supracrustal sequences limiting availability of data. The primary sources of samples from the MHB are 1) xenoliths of variable metamorphic grade including gneisses amphibolites and meta-plutonic rocks collected from Eocene volcanic rock; and 2) similar lithologies recovered from boreholes that penetrate to the MHB basement. Previous work on samples from the MHB yielded …


Gypsum Karst Speleogenesis In Barber County, Kansas Of The Permian Blaine Formation, Kaitlyn Gauvey 2019 Fort Hays State University

Gypsum Karst Speleogenesis In Barber County, Kansas Of The Permian Blaine Formation, Kaitlyn Gauvey

Master's Theses or Doctor of Nursing Practice

Field reconnaissance examining the Permian Blaine Formation and the karst features within those rocks were conducted on two ranches in Barber County, Kansas. Karst features are developed dominantly in gypsum and include caves, sinkholes, losing streams, springs, and other surficial karst features. The Blaine Formation is known as a significant karst unit and major aquifer system in Oklahoma; however, little work has been conducted in Kansas. This study identifies the processes that lead to karst development in the Blaine Formation in Kansas and represents the first stage of a karst study to develop predictive karst models. This survey of caves …


How To Search For Life In Martian Chemical Sediments And Their Fluid And Solid Inclusions Using Petrographic And Spectroscopic Methods, Kathleen C. Benison 2019 West Virginia University

How To Search For Life In Martian Chemical Sediments And Their Fluid And Solid Inclusions Using Petrographic And Spectroscopic Methods, Kathleen C. Benison

Faculty & Staff Scholarship

Abundant resources and efforts have been employed in the search for life on Mars. Satellites, landers, and rovers have tested atmospheric gases, general sediment and rock compositions, and images of Mars surface in an effort to detect biosignatures left by any possible modern or ancient life. Chloride and sulfate minerals suggestive of past acid saline lakes have been found on Mars. In terrestrial acid brine environments, these minerals trap microorganisms and organic compounds and preserve them within fluid inclusions and as solid inclusions for long geologic time periods. Some cells remain viable, especially in the isolated, microscopic aqueous environments of …


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