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Palynological Studies Of Holocene Lake Sediments In The Missouri Ozarks, Robert D. Haselwander 2016 Missouri University of Science and Technology

Palynological Studies Of Holocene Lake Sediments In The Missouri Ozarks, Robert D. Haselwander

Doctoral Dissertations

"Five small lakes in southeast Missouri (Frisco, Pine Forest, and Bray Area lakes [Phelps County], and Cypress and Blue ponds [Bollinger County]) were cored for paleolimnological studies. Cores were evaluated for their sedimentology, palynology, and geochemistry. In two of these lakes (Bray Area and Pine Forest lakes) the planktonic algae were also studied in the water column, along with ecological parameters. Algae in the sediments were compared to algae in the water to understand the resistance of different species to decay, and a suggested methodology for this work is described. Reconstructions of the past environments around each lake were created …


Structural And Stratigraphic Development Of A Salt Diapir Shoulder, Gypsum Valley, Colorado, Joshua Coleman Mcfarland 2016 University of Texas at El Paso

Structural And Stratigraphic Development Of A Salt Diapir Shoulder, Gypsum Valley, Colorado, Joshua Coleman Mcfarland

Open Access Theses & Dissertations

A salt shoulder is a low-angle segment of the salt-sediment interface where the margin of a passive diapir steps abruptly inboard. The Late Triassic Chinle Formation overlies caprock on the northeastern margin of Gypsum Valley (GV) at the salt-sediment interface in the natural amphitheater of Bridge Canyon. Modern erosion of the Dolores River has created 3D outcrop of the salt shoulder, expressed by a 500 meter wide, sub-horizontal platform that dips abruptly into the subsurface to the northeast toward the Dry Creek minibasin. Within Bridge Canyon, seven facies associations have been recognized and interpreted within the Chinle Formation: 1) non-caprock …


An Integrated Geophysical Survey Of Kilbourne Hole, Southern New Mexico: Implications For Near Surface Exploration Of Mars And The Moon, Nisa Maksim 2016 University of Texas at El Paso

An Integrated Geophysical Survey Of Kilbourne Hole, Southern New Mexico: Implications For Near Surface Exploration Of Mars And The Moon, Nisa Maksim

Open Access Theses & Dissertations

Features such as the Home Plate plateau on Mars, a suspected remnant of an ancient phreatomagmatic eruption, can reveal important information about paleohydrologic conditions. The eruption intensity of a phreatomagmatic volcano is controlled mainly by the quantity of water and magma, the internal geometry of the volcano, and the depth of the interaction zone between magma and water. In order to understand the paleohydrologic conditions at the time of eruption, we must understand all the factors that influenced the phreatomagmatic event. I conducted an integrated geophysical survey, which are magnetic and gravity surveys, and a ground-penetrating radar (GPR) surveys at …


National Evaluation For Development And Exploration Potential Of Mineral Commodities In Produced Waters, Stephanie Ray 2016 University of Texas at El Paso

National Evaluation For Development And Exploration Potential Of Mineral Commodities In Produced Waters, Stephanie Ray

Open Access Theses & Dissertations

The U.S. Geological Survey recently updated a geochemical database consisting of data for approximately 160,000 produced waters samples, primarily from petroleum and geothermal reservoirs. Using major and trace elements from conventional and unconventional well types from the database, this Thesis provides a comprehensive, national evaluation for mineral commodity potential in produced waters. Produced waters contain virtually every naturally occurring element and can range in salinity to several times that of seawater. Despite the typical outlook to view produced waters as a waste, they have potential for natural resource development.

This Thesis provides, for each mineral commodity found in the produced …


Investigation Of Lunar Subsurface Cavities Using Thermal Inertia And Temperature Maximum To Minimum Ratios, Rachel Ann Slank 2016 University of Texas at El Paso

Investigation Of Lunar Subsurface Cavities Using Thermal Inertia And Temperature Maximum To Minimum Ratios, Rachel Ann Slank

Open Access Theses & Dissertations

Previous studies have revealed a small number of subsurface cavities, including lava tubes, as well as skylights, lava flow pits, and impact melt pits on the Moon. The interiors of subsurface cavities would have been protected from micrometeorite bombardment, solar radiation, space weathering, and extreme diurnal temperature swings over long periods of geologic time. As a result, subsurface cavities can provide access to pristine crustal samples and stratigraphy. These cavities may also harbor important volatiles, such as water ice, that would enable future exploration missions by relieving many operational constraints, including the supply of propellants and life support. In addition, …


Debris Flow Susceptibility Map For Mount Rainier, Washington Based On Debris Flow Initiation Zone Characteristics From The November, 2006 Climate Event In The Cascade Mountains, Kassandra Lindsey 2015 Portland State University

Debris Flow Susceptibility Map For Mount Rainier, Washington Based On Debris Flow Initiation Zone Characteristics From The November, 2006 Climate Event In The Cascade Mountains, Kassandra Lindsey

Dissertations and Theses

In November 2006 a Pineapple Express rainstorm moved through the Pacific Northwest generating record precipitation, 22 to 50 cm in the two-day event on Mt. Rainier. Copeland (2009) and Legg (2013) identified debris flows in seven drainages in 2006; Inter Fork, Kautz, Ohanapecosh, Pyramid, Tahoma, Van Trump, and West Fork of the White River. This study identified seven more drainages: Carbon, Fryingpan, Muddy Fork Cowlitz, North Puyallup, South Mowich, South Puyallup, and White Rivers. Twenty-nine characteristics, or attributes, associated with the drainages around the mountain were collected. Thirteen were used in a regression analysis in order to develop a susceptibility …


Pre-Mission Input Requirements To Enable Successful Sample Collection By A Remote Field/Eva Team, Barbara A. Cohen, Darlene S. S. Lim, Kelsey E. Young, Anna Brunner, Richard C. Elphic, Audrey Horne, Mary C. Kerrigan, Gordon O. Osinski, John R. Skok, Steven W. Squyres, David Saint-Jacques, Jennifer L. Heldmann 2015 NASA Marshall Space Flight Center

Pre-Mission Input Requirements To Enable Successful Sample Collection By A Remote Field/Eva Team, Barbara A. Cohen, Darlene S. S. Lim, Kelsey E. Young, Anna Brunner, Richard C. Elphic, Audrey Horne, Mary C. Kerrigan, Gordon O. Osinski, John R. Skok, Steven W. Squyres, David Saint-Jacques, Jennifer L. Heldmann

Journal of Human Performance in Extreme Environments

We used a field excursion to the West Clearwater Lake Impact structure as an opportunity to test factors that contribute to the decisions a remote field team (for example, astronauts conducting extravehicular activities (EVA) on planetary surfaces) makes while collecting samples for return to Earth. We found that detailed background on the analytical purpose of the samples, provided to the field team, enables them to identify and collect samples that meet specific analytical objectives. However, such samples are not always identifiable during field reconnaissance activities, and may only be recognized after outcrop characterization and interpretation by crew and/or science team …


Apparent Glacially Induced Structural Controls On Limestone Conduit Development In Ohio Caverns, United States, Adrienne M. Watts, Ira D. Sasowsky 2015 University Of Akron

Apparent Glacially Induced Structural Controls On Limestone Conduit Development In Ohio Caverns, United States, Adrienne M. Watts, Ira D. Sasowsky

International Journal of Speleology

Rock discontinuities such as bedding planes and joints are important controls on the form that caves take. We examined structural controls on the development of Ohio Caverns. The cave formed in Devonian limestone underlying a small bedrock knob (Mt. Tabor) within the Interior Lowland province, United States. The area has been overridden by continental glaciation multiple times. The bedrock is pervasively fractured, with many curved and wavy near-vertical fractures showing many different orientations. In the case of Ohio Caverns, it appears that the controlling fractures in map view may not be joints sensu stricto, but rather some combination of …


Dendrochronology And Middle Miocene Petrified Oak: Modern Counterparts And Interpretation, William E. Wright, Martin J. Streck, Christopher Baisan, W. Walton Wright, Paul Szejner 2015 University of Arizona

Dendrochronology And Middle Miocene Petrified Oak: Modern Counterparts And Interpretation, William E. Wright, Martin J. Streck, Christopher Baisan, W. Walton Wright, Paul Szejner

Geology Faculty Publications and Presentations

This study reports the first successful statistical crossdating among many ring width time series from petrified wood, thus providing a replicable continuous annual resolution window into tree growth and environmental influences during the middle Miocene. The petrified samples, of the genus Quercus, originated at the Stinking Water (SW) locality in Oregon, a Miocene-aged exposure associated with the Columbia River Basalts. 40AR/39AR dating on pillow basalt from the locality yielded a weighted Plateau Age of 13.79 ±0.09 Ma placing the death of the trees at the end of the Langhian Stage of the Middle Miocene (15.97±0.05 to 13.65±0.05 …


Petroleum Play Study Of The Keathley Canyon, Gulf Of Mexico, Jean Pierre Malbrough 2015 LSU New Orleans

Petroleum Play Study Of The Keathley Canyon, Gulf Of Mexico, Jean Pierre Malbrough

LSU New Orleans Theses and Dissertations

Beneath Keathley Canyon (KC) off the Southern Coast of Louisiana and Texas, allochthonous salt bodies have attained thicknesses of over 7620 m (25000 feet), providing excellent seals and migration pathways for hydrocarbons produced by post-rift sedimentary deposition. This study analyzes a small portion of the KC area, utilizing Petrel Seismic software and well information from the KC102 (Tiber) well.

An intra-Miocene wedge, expressed beneath salt, may provide information about movement of allochthonous salt over Wilcox sands, sediment compaction, and hydrocarbon pathways. Progradational sedimentation is the driving force which leads to faulting in the early Miocene, allowing Jurassic salt to rise, …


Submarine Channel Evolution Linked To Rising Salt Dome, Mississippi Canyon, Gulf Of Mexico, Rachel C. Carter 2015 University of New Orleans

Submarine Channel Evolution Linked To Rising Salt Dome, Mississippi Canyon, Gulf Of Mexico, Rachel C. Carter

LSU New Orleans Theses and Dissertations

By examining halokinetics and channel evolution in a deep-water system, we investigate how submarine channel morphology is affected by changing seascape linked to diapirism. The study area is located in Mississippi Canyon, Gulf of Mexico (GOM), situated directly off the continental slope in a prominent salt dome region. Interactions of salt domes with submarine channels in the GOM are poorly documented. Utilizing 3D seismic data and seismic geomorphology techniques, a long-lived Plio-Pleistocene submarine channel system has been investigated to develop a relationship between variable phases of salt movement and plan-form morphology of preserved channels.

We suggest that halokinetics acts as …


Mineralogy And Geochemistry Of Late Archean And Paleoproterozoic Granites And Pegmatites In The Northern Penokean Terrane Of Marquette And Dickinson Counties, Michigan, Christopher M. Johnson, Christopher M. Van Daalen 2015 LSU New Orleans

Mineralogy And Geochemistry Of Late Archean And Paleoproterozoic Granites And Pegmatites In The Northern Penokean Terrane Of Marquette And Dickinson Counties, Michigan, Christopher M. Johnson, Christopher M. Van Daalen

LSU New Orleans Theses and Dissertations

This thesis focuses on mineralogy, geochemistry, and origin of eight pegmatites and two spatially associated granites of Late Archean and Paleoproterozoic ages located in Marquette and Dickinson Counties, Michigan. Biotite geochemistry reveals that both granites and all pegmatites are peraluminous and have an orogenic signature. However, bulk composition reveals the Humboldt granite is a peraluminous A-type granite and the Bell Creek granite is a peraluminous mix between I-, S-, and A-type granites. The Republic Mine pegmatite appears to be geochemically similar to the Bell Creek granite and Grizzly pegmatite. The Crockley pegmatite is genetically related to the Humboldt granite. The …


A Seismic Transect Across West Antarctica: Evidence For Mantle Thermal Anomalies Beneath The Bentley Subglacial Trench And The Marie Byrd Land Dome, Andrew J. Lloyd, Douglas A. Wiens, Andrew A. Nyblade, Sridhar Anandakrishnan, Richard C. Aster, Audrey D. Huerta, Terry J. Wilson, Ian W. D. Dalziel, Patrick J. Shore, Dapeng Zhao 2015 Washington University in St. Louis

A Seismic Transect Across West Antarctica: Evidence For Mantle Thermal Anomalies Beneath The Bentley Subglacial Trench And The Marie Byrd Land Dome, Andrew J. Lloyd, Douglas A. Wiens, Andrew A. Nyblade, Sridhar Anandakrishnan, Richard C. Aster, Audrey D. Huerta, Terry J. Wilson, Ian W. D. Dalziel, Patrick J. Shore, Dapeng Zhao

All Faculty Scholarship for the College of the Sciences

West Antarctica consists of several tectonically diverse terranes, including the West Antarctic Rift System, a topographic low region of extended continental crust. In contrast, the adjacent Marie Byrd Land and Ellsworth-Whitmore mountains crustal blocks are on average over 1km higher, with the former dominated by polygenetic shield and stratovolcanoes protruding through the West Antarctic ice sheet and the latter having a Precambrian basement. The upper mantle structure of these regions is important for inferring the geologic history and tectonic processes, as well as the influence of the solid earth on ice sheet dynamics. Yet this structure is poorly constrained due …


Quaternary Chronology And Stratigraphy Of Mickey Springs, Oregon, Leslie Allen Mowbray 2015 Portland State University

Quaternary Chronology And Stratigraphy Of Mickey Springs, Oregon, Leslie Allen Mowbray

Dissertations and Theses

Mickey Springs in the Alvord Desert, southeast Oregon, is analogous to other Basin and Range hydrothermal systems where the requisite conditions of heat source and permeable pathways are met through crustal thinning due to normal faulting. This study examines the morphology and lifespan of near-surface spring features through use of ground penetrating radar, thermoluminescence (TL) dating, and elevation modeling. Duration of hydrothermal activity at Mickey Springs has not previously been determined, and age determinations of sinter at the site are conflicting. The reason for and timing of this change in silica saturation in the hydrothermal fluid has not been resolved. …


Mobile Mud Dynamics In The East China Sea Elucidated Using 210pb, 137cs, 7be, And 234th As Tracers, Jinlong Wang, Jinzhou Du, Mark Baskaran, Jing Zhang 2015 East China Normal University

Mobile Mud Dynamics In The East China Sea Elucidated Using 210pb, 137cs, 7be, And 234th As Tracers, Jinlong Wang, Jinzhou Du, Mark Baskaran, Jing Zhang

Environmental Science and Geology Faculty Research Publications

“Mobile mud” (MM), which has fine grain size distribution (>90% clay + silt, and <5% sand) and high porosity (≥0.50), plays an important role in the biogeochemical cycles in the estuarine areas and the inshore shelf. A suite of MM samples from the coastal area of the East China Sea (ECS) was collected in spring and summer of 2011 to observe their spatial and temporal distribution, grain size, and radionuclides concentrations. The MM thickness ranged from 0.5 to 11 cm (average: 2.2 cm (May) and 3.9 cm (August)). The thick mud layer is mainly distributed along the coast, with an area of 2.2 × 104 km2 in May and 1.5 × 104 km2 in August, with corresponding masses of 8.8 × 108 and 7.8 × 108 t, respectively. The estimated masses of MM are considerably larger than the annual sediment discharge mass of the Changjiang River. The distribution of 137Cs inventories in MM indicates that 137Cs can be effectively utilized as a transport tracer of MM in the river‐dominated estuaries and coastal areas. The higher inventories of 7Be in MM in the river mouth in spring are attributed to higher depositional flux and higher sediment discharge. The ratio of the MM inventory of 234Thex/production in the overlying water column of >2.5 in south inshore indicates that the sediment focusing resulted in the increased mass flux. The residence time of MM is estimated as 3–6 years both by mass balance of MM and 210Pbex in MM.


Elevation Promotes Long-Term Survival Of Pinus Elliottii Var. Densa, A Foundation Species Of The Endangered Pine Rockland Ecosystem In The Florida Keys, Grant L. Harley, Justin T. Maxwell, George T. Raber 2015 University of Southern Mississippi

Elevation Promotes Long-Term Survival Of Pinus Elliottii Var. Densa, A Foundation Species Of The Endangered Pine Rockland Ecosystem In The Florida Keys, Grant L. Harley, Justin T. Maxwell, George T. Raber

Faculty Publications

The pine rockland community in southern Florida, which supports numerous state- and federally listed flora and fauna species, is considered endangered. Without its foundation species, Pinus elliottii var. densa, habitat and species diversity are lost to tropical hardwood hammock. Here, we investigate the landscape factors that contribute to the long-term persistence of pine rocklands on the 2 islands that contain the largest remaining habitat in the Florida Keys: Big Pine Key and No Name Key. Plot-level biophysical data and island-scale remotely sensed vegetation data were collected from pine rockland savannas and examined with multi-dimensional analysis. On both islands, vegetation …


The Genesis Of A Lava Cave In The Deccan Volcanic Province (Maharashtra, India), Nikhil R. Pawar, Amod H. Katikar, Sudha Vaddadi, Sumitra H. Shinde, Sharad N. Rajaguru, Sachin V. Joshi, Sanjay P. Eksambekar 2015 Nowrosjee Wadia College, India

The Genesis Of A Lava Cave In The Deccan Volcanic Province (Maharashtra, India), Nikhil R. Pawar, Amod H. Katikar, Sudha Vaddadi, Sumitra H. Shinde, Sharad N. Rajaguru, Sachin V. Joshi, Sanjay P. Eksambekar

International Journal of Speleology

Lava tubes and channels forming lava distributaries have been recognized from different parts of western Deccan Volcanic Province (DVP). Openings of smaller dimension have been documented from the pāhoehoe flows around Pune, in the western DVP. A small lava cave is exposed in Ghoradeshwar hill, near Pune. Detailed field studies of the physical characteristics, structure and morphology of the flows hosting the lava tube has been carried out. This is the first detailed documentation of a lava cave from the DVP. The lava cave occurs in a compound pāhoehoe flow of Karla Formation, characterized by the presence of lobes, toes …


Mantle-Derived Helium In Hot Springs Of The Cordillera Blanca, Peru: Implications For Mantle-To-Crust Fluid Transfer In A Flat-Slab Subduction Setting, Dennis L. Newell, Micah J. Jessup, David R. Hilton, Colin Shaw, Cameron Hughes 2015 Utah State University

Mantle-Derived Helium In Hot Springs Of The Cordillera Blanca, Peru: Implications For Mantle-To-Crust Fluid Transfer In A Flat-Slab Subduction Setting, Dennis L. Newell, Micah J. Jessup, David R. Hilton, Colin Shaw, Cameron Hughes

Geosciences Faculty Publications

Fault-controlled hot springs in the Cordillera Blanca, Peru provide geochemical evidence of mantle-derived fluids in a modern flat-slab subduction setting. The Cordillera Blanca is an ~200km-long mountain range that contains the highest peaks in the Peruvian Andes, located in an amagmatic reach of the Andean arc. The Cordillera Blanca detachment defines the southwestern edge of the range and records a progression of top-down-to-the-west ductile shear to brittle normal faulting since ~5Ma. Hot springs, recording temperatures up to 78°C, issue along this fault zone and are CO2-rich, near neutral, alkaline-chloride to alkaline-carbonate waters, with elevated trace metal contents including …


Nebraska's Public Access Hunting Program: Hunter Preferences And Usage Final Report, Lisa Pennisi, Mark E. Burbach, Namyun Kil, Muhammed Imran Kahn, Andrew J. Tyre 2015 University of Nebraska-Lincoln

Nebraska's Public Access Hunting Program: Hunter Preferences And Usage Final Report, Lisa Pennisi, Mark E. Burbach, Namyun Kil, Muhammed Imran Kahn, Andrew J. Tyre

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Deep Fluid Inputs Into The Continental-Scale Nubian Sandstone Aquifer System Constrained By Hydrochemical, Stable Isotope, And Noble Gas Data, Abdel Mawgoud Mohammed 2015 Western Michigan University

Deep Fluid Inputs Into The Continental-Scale Nubian Sandstone Aquifer System Constrained By Hydrochemical, Stable Isotope, And Noble Gas Data, Abdel Mawgoud Mohammed

Dissertations

The Nubian Sandstone Aquifer System (NSAS) of northeastern Africa is one of the largest confined fossil-water aquifer systems in the world, with several nations relying on it (Egypt, Libya, Sudan and Chad). This groundwater is the biggest and in some cases the only future source of water to meet the development goals of each NSAS country. This study provides new geochemical data from the main oases of the Western Desert of Egypt and a compilation of published hydrochemical data from the regional aquifer. Interpretation of results suggests heterogeneous fluid mixing within the aquifer, the potential for hydrochemical sub-basins, and a …


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