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Detrital Carbonates In A Sequence Stratigraphic Framework: An Example From The Furongian Slope Environment In The Hot Creek Range Of Central Nevada, Leon Taufani 2012 University of Nevada, Las Vegas

Detrital Carbonates In A Sequence Stratigraphic Framework: An Example From The Furongian Slope Environment In The Hot Creek Range Of Central Nevada, Leon Taufani

UNLV Theses, Dissertations, Professional Papers, and Capstones

An integrated sedimentological study of detrital carbonates of the late Cambrian (Furongian) Hales Limestone in central Nevada was conducted in order to model facies distribution and controlling mechanisms of carbonate gravity-flow deposits. Seven closely-spaced sections and numerous traceable short sections were measured to investigate temporal and spatial changes of detrital carbonates within a high-resolution stratigraphic framework supported by biostratigraphic and carbon isotope chemostratigraphic constraints and by key physical surfaces. Polished slabs and thin section petrographic analysis were used to identify micro- and macro-scale textures and diagenesis.

Ten lithofacies are identified from the Hales Limestone. Lateral tracing of these facies reveals …


Autumn Migration Of Mississippi Flyway Mallards As Determined By Satellite Telemetry, David George G. Krementz, Kwasi Asante, Luke W. Naylor 2012 University of Arkansas, Fayetteville

Autumn Migration Of Mississippi Flyway Mallards As Determined By Satellite Telemetry, David George G. Krementz, Kwasi Asante, Luke W. Naylor

United States Geological Survey: Staff Publications

We used satellite telemetry to study autumn migration timing, routes, stopover duration, and final destinations of mallards Anas platyrhynchos captured the previous spring in Arkansas from 2004 to 2007. Of those mallards that still had functioning transmitters on September 15 (n = 55), the average date when autumn migration began was October 23 (SE = 2.62 d; range = September 17–December 7). For those mallards that stopped for .1 d during migration, the average stopover length was 15.4 d (SE = 1.47 d). Ten mallards migrated nonstop to wintering sites. The eastern Dakotas were a heavily utilized stopover area. The …


A Study Of The Bioherms Of The Early Ordovician Garden City Formation And A Literature Review Of Early Ordovician Organic Buildups, Heidi Pearce 2012 Utah State University

A Study Of The Bioherms Of The Early Ordovician Garden City Formation And A Literature Review Of Early Ordovician Organic Buildups, Heidi Pearce

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

During the Early Ordovician organic buildups formed in shallow seas across the world. This project contains a literature review on these organic buildups with a focus on those occurring in the warm, shallow seas of North America, but also includes a study on organic buildups formed in the cold water region of Russia. The goal of the study was to characterize these Early Ordovician organic buildups in order to identify similarities and differences in their occurrence. The second part of this project is a preliminary study on organic buildups occurring in the Early Ordovician Garden City Formation in Boss Canyon, …


Stratigraphic Framework For Deposits Of The Saginaw Lobe, Barry And Calhoun Counties, Michigan, Usa, Stephanie K. Ewald 2012 Western Michigan University

Stratigraphic Framework For Deposits Of The Saginaw Lobe, Barry And Calhoun Counties, Michigan, Usa, Stephanie K. Ewald

Masters Theses

Between 2006 and 2012, twelve rotasonic borings were drilled in Barry and Calhoun Counties, south central Michigan, as part of several Great Lakes Geological Mapping Coalition projects. Natural gamma ray logs were collected at every location and a detailed description and textural analysis was completed for seven of these cores. Five of the seven analyzed cores reached bedrock. Six of the seven borings were drilled north of the Kalamazoo Moraine of the Saginaw Lobe, which was constructed during retreat of the lobe after the Late Glacial Maximum. Five borings, drilled in tunnel valleys, indicate an increase in depth of tunnel …


Characterizing The Internal Architecture Of Upper Bone Spring Limestone Turbidites And Mass-Transport Deposits (Mtds) Utilizing High-Resolution Image Log Technology, Jason J. Asmus 2012 Western Michigan University

Characterizing The Internal Architecture Of Upper Bone Spring Limestone Turbidites And Mass-Transport Deposits (Mtds) Utilizing High-Resolution Image Log Technology, Jason J. Asmus

Masters Theses

Characterization of reservoir scale (less than 1 meter thick) turbidites and mass-transport deposits (MTDs) using conventional subsurface data is complex, due to millimeter-centimeter scale architectural heterogeneity exhibited by these deposits.

Limited studies of the Bone Spring carbonate turbidites and MTDs within the Delaware Basin subsurface emphasized the use of conventional wire-line log and seismic data to evaluate reservoir potential of such strata. As a result, limited resolution offered by these data sets do not allow for accurate characterization of reservoir, and sub-reservoir scale, architectural and compositional variations.

The present investigation integrates high-resolution (centimeter scale) electrical borehole image logs with conventional …


Hydromechanical Well Testing Using A 3d Fiber Optic Extensometer, Glenn Skawski 2012 Clemson University

Hydromechanical Well Testing Using A 3d Fiber Optic Extensometer, Glenn Skawski

All Theses

Some fractured rock formations hold important resources, such as water, hydrocarbons or heat, whereas others are good candidates for waste disposal. Hydromechanical well tests have been developed to improve characterization of formation properties and parameter distributions by measuring displacement along with pressure while stressing a well. The displacement that occurs during a well test depends on the geometry of fractures or other sources of permeability, as well as the distribution of compliance or elastic modulus. Current methods of hydromechanical well testing, measures axial displacements along a wellbore, which may cause ambiguity in interpretations when 3-D components of deformation are present. …


The Impact Of Creosote Bush (Larrea Tridentata) And Biological Soil Crust On Ca Distribution In Arid Soils Of The Mojave Desert, Brittany Myers 2012 University of Nevada, Las Vegas

The Impact Of Creosote Bush (Larrea Tridentata) And Biological Soil Crust On Ca Distribution In Arid Soils Of The Mojave Desert, Brittany Myers

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ca is an important nutrient that plays a role in membrane stability and cell repair in plant life. This study examines the impact of creosote bush (Larrea tridentata) and biological soil crust on calcium cycling and distribution in desert soils in order to explore the use of Ca as a biosignature. Samples of creosote bush, biological soil crust and eolian dust were taken at two field sites in the Mojave Desert. The first site is located in Eldorado Valley, NV, a soil formed on a young (800-1200 years) alluvial fan deposit; the second site is located on a late Holocene-aged …


Diagenesis And Reservoir Characterization Of The Pennsylvanian Middle Atoka Formation, Sebastian And Logan Counties, West-Central Arkansas, Elvis Chekwube Bello 2012 University of Arkansas, Fayetteville

Diagenesis And Reservoir Characterization Of The Pennsylvanian Middle Atoka Formation, Sebastian And Logan Counties, West-Central Arkansas, Elvis Chekwube Bello

Graduate Theses and Dissertations

The Middle Atoka Formation evolved from a stable passive margin during the early Pennsylvanian time to a rapidly subsiding basin, with the sedimentary fill thickening greatly southward during the middle Pennsylvanian time. The basin dips in north-south direction. An east-west anticlines and synclines were observed.

The purpose of this study is to establish the stratigraphic units, reservoir geometry and distribution, and infer the depositional environments and reservoir quality. Well correlation and petrographic studies are used to achieve the goals.

Sandstone Point Count method was used. The Point Counts was divided into five categories. They include the framework grains (quartz, feldspar, …


Stratigraphic Variations In The Carboniferous Section Across The Arkansas-Oklahoma State Line Arch, Tyler Dean Engelhardt 2012 University of Arkansas, Fayetteville

Stratigraphic Variations In The Carboniferous Section Across The Arkansas-Oklahoma State Line Arch, Tyler Dean Engelhardt

Graduate Theses and Dissertations

The State Line Arch is represented by a structural high that trends through the study area in a loose alignment with the Arkansas-Oklahoma state line. Evidence of the arch extending further to the north includes a structural high and stratigraphic variation at an outcrop on Highway 59 near Evansville Mountain in Crawford County, Arkansas. The exact timing of the formation of the arch remains undetermined, but upper Devonian thinning at the top of the arch indicates the structure is pre-Mississippian. The reason for the development of the arch is poorly understood, but evidence linking Mississippian-aged Waulsortian mounds to Precambrian Spavinaw …


Modeling Lithospheric Rheology From Modern Measurements Of Bonneville Shoreline Deformation, Eric P. Beard 2012 Utah State University

Modeling Lithospheric Rheology From Modern Measurements Of Bonneville Shoreline Deformation, Eric P. Beard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Here I develop a new method for estimating differences in elevation between pairs of paleo-lake shoreline features. This method is applied to Lake Bonneville, a large lake that inundated nearly 1/3 of the state of Utah as well as parts of Nevada and Idaho from 34 to 11.5 thousand years ago. Under the weight of the lake water load, the surface of the Earth was depressed by up to 75 m. This occurred as Earth mantle rock at depth flowed outward in response to the weight of the lake. I use this new methodology to compile here a denser sample …


Ore And Gangue Mineral Paragenesis Of The Cortez Hills Carlin-Type Gold Deposit, Nevada: Evidence For Coincident High-Grade Gold Deposition And Collapse Brecciation, Lindsey R. Clark 2012 University of Nevada, Las Vegas

Ore And Gangue Mineral Paragenesis Of The Cortez Hills Carlin-Type Gold Deposit, Nevada: Evidence For Coincident High-Grade Gold Deposition And Collapse Brecciation, Lindsey R. Clark

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Cortez Hills Carlin-type gold deposit (CTGD), located on the Battle Mountain-Eureka trend of Northern NV, is hosted in a conical shaped polylithic breccia whose central axis strikes parallel to the imbricate Voodoo fault system. Gold grades at the center of the Cortez Hills Breccia Zone (CHBZ) are locally in excess of an ounce per ton. Gold mineralization within the refractory ore at Cortez Hills shares many characteristics with other well studied CTGDs. However, new observations during this study have recognized 1) fragmented realgar that are rimmed by gold-bearing iron-sulfide minerals in four samples, 2) a Hg- and Tl-rich late-ore …


Petrogenesis Of The East Fork Member Rhyolites, Valles Caldera, New Mexico, Usa, Carla Eichler 2012 University of Nevada, Las Vegas

Petrogenesis Of The East Fork Member Rhyolites, Valles Caldera, New Mexico, Usa, Carla Eichler

UNLV Theses, Dissertations, Professional Papers, and Capstones

The most recent volcanism in the Valles caldera is represented by the El Cajete Pyroclastic Beds (ECPB), Battleship Rock Ignimbrite (BRI), and Banco Bonito Flow (BBF) as well as the VC-1 rhyolite, which are collectively known as the East Fork Member (EFM) of the Valles Rhyolite. The EFM was erupted at approximately 55 ka and 40 ka after an approximate 460 ka lull in volcanism. Previous studies suggested a mafic intrusion at depth triggered the eruptions. This thesis represents the first detailed study of the EFM.

Crystal assemblages consist of plagioclase, biotite, clinopyroxene, orthopyroxene, amphibole, sanidine, quartz, and oxides. Electron …


Volcanic Evolution Of The Southern Quinn Canyon Range: Implications For Regional Correlation Of Volcanic Units, Christina Emery 2012 University of Nevada, Las Vegas

Volcanic Evolution Of The Southern Quinn Canyon Range: Implications For Regional Correlation Of Volcanic Units, Christina Emery

UNLV Theses, Dissertations, Professional Papers, and Capstones

The southern Quinn Canyon Range lies in an area of the Great Basin subjected to large-volume Oligocene-Miocene silicic volcanism and smaller volume basaltic volcanism during the Pliocene. Three major ash-flow tuff units were correlated in the southern Quinn Canyon Range (the Pahranagat Tuff, Clifford Spring Tuff, and the Cow Canyon Tuff) with regional units by utilizing U/Pb and 40 Ar/ 39Ar geochronology, geochemical correlation, and field mapping. Isotopic analysis suggests that basalt in the southern Quinn Canyon Range is part of the Death Valley-Pancake Range Basalt Zone and is similar to Reveille Range Episode 1 and 2 basalts. Further comparison …


An Estimate Of Groundwater Recharge In The Nabogo River Basin, Ghana Using Water Table Fluctuation Method And Chloride Mass Balance, Melanie Lynn Krautstrunk 2012 University of Nevada, Las Vegas

An Estimate Of Groundwater Recharge In The Nabogo River Basin, Ghana Using Water Table Fluctuation Method And Chloride Mass Balance, Melanie Lynn Krautstrunk

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Cambrian-Precambrian fractured sandstone aquifer in the Nabogo River Basin in the Sahelian Northern Region in Ghana is one of the most important sources for fresh water supply for the local rural communities there. Recent population growth and commercial agricultural interests in this region could have an impact on this critical water resource. Groundwater recharge estimates are determined in this study using the Water Table Fluctuation Method and Chloride Mass Balance and can be applied to future sustainability studies of the region's water resources. Recharge estimates of the Water Table Fluctuation Method are in a range of 10-143 mm/yr or …


2000 Year Moisture Source Record From A Central Nevada Speleothem, Paul Pribyl 2012 University of Nevada, Las Vegas

2000 Year Moisture Source Record From A Central Nevada Speleothem, Paul Pribyl

UNLV Theses, Dissertations, Professional Papers, and Capstones

The goal of this study was to determine the moisture source of winter precipitation in the central Great Basin for the past 2000 years, and to elucidate the role of Pacific Ocean and North American climate variability modes in driving observed droughts of the region around the Medieval Climatic Anomaly (MCA, ~900-1300 CE). Here a high resolution (~2-4 year) precisely dated moisture source reconstruction is presented from the δ18O values of speleothem LC-1 collected from Leviathan Cave in central Nevada, which reveals significant δ18O variability. I attribute the δ18O variability to changes in winter-season moisture circulation over the past 2000 …


Penetration Forces For Subsurface Regolith Probes, Ahmed Elshafie 2012 University of Arkansas, Fayetteville

Penetration Forces For Subsurface Regolith Probes, Ahmed Elshafie

Graduate Theses and Dissertations

Investigating planetary bodies using penetrometers can provide detailed information about its history and evolution. An estimation of subsurface density and porosity can be made from the shape of the penetration curve. Using penetrometers mounted on planetary platforms could be challenging due to the uncertainty of the subsurface composition and since the maximum allowed force for penetration is the weight of the lander or rover on the surface. Estimation of penetration forces can provide a reliable constraint on the maximum reachable depth without endangering the whole mission. Therefore, knowledge of the required penetration force to specific depths can be helpful in …


Integrated Approach For Hydrogeologic Investigations In Africa: Inferences From Space-Borne And Land-Based Gravity, Aeromagnetic, Gis, And Remote Sensing Data, Mohamed El Sayed Ahmed Ahmed 2012 Western Michigan University

Integrated Approach For Hydrogeologic Investigations In Africa: Inferences From Space-Borne And Land-Based Gravity, Aeromagnetic, Gis, And Remote Sensing Data, Mohamed El Sayed Ahmed Ahmed

Dissertations

An integrated (space-borne and land-based gravity, aeromagnetic, GIS, and remote sensing) approach was developed, tested, and applied to investigate the following on regional scales (Africa) or local scales (El Qaa Plain, Sinai): (1) assess the capability of GRACE data (04/2002 to 08/2011) for monitoring elements of hydrologic systems on the sub-basin level (Task 1); (2) address the nature and the controlling factors (e.g., climatic and/or human pressure-related) affecting the inter-annual GRACE-derived Terrestrial Water Storage (TWS) trends over a large suite of hydrologic systems and domains in (Africa) (Task 2); and (3) identify the structural, geologic and hydrologic settings as well …


Inventory And Initiation Zone Characterization Of Debris Flows On Mount St. Helens, Washington Initiated During A Major Storm Event In November, 2006, Keith Vinton Olson 2012 Portland State University

Inventory And Initiation Zone Characterization Of Debris Flows On Mount St. Helens, Washington Initiated During A Major Storm Event In November, 2006, Keith Vinton Olson

Dissertations and Theses

The heavy precipitation event of November 3-8, 2006 dropped over 60 cm of rain onto the bare southern slopes of Mount St. Helens and generated debris flows in eight of the sixteen drainages outside the 1980 debris avalanche zone. Debris flows occurred on the upper catchments of the Muddy River, Shoestring Glacier, Pine Creek, June Lake, Butte Camp Dome, Blue Lake, Sheep Creek, and South Fork Toutle River. Debris flows were clustered on the west and south-east sides of the mountain. Of the eight debris flows, three were initiated by landslides, while five were initiated by headward or channel erosion. …


Temporal And Crustal Effects On Differentiation Of Tholeiite To Calcalkaline And Ferro-Trachytic Suites, High Lava Plains, Oregon, Usa, Martin J. Streck, Anita L. Grunder 2012 Portland State University

Temporal And Crustal Effects On Differentiation Of Tholeiite To Calcalkaline And Ferro-Trachytic Suites, High Lava Plains, Oregon, Usa, Martin J. Streck, Anita L. Grunder

Geology Faculty Publications and Presentations

Strongly bimodal, basalt-rhyolite volcanism of the High Lava Plains Province of Oregon followed the Middle Miocene flood basalts of the Pacific Northwest and extends to recent time. During the 8 m.y. of volcanism recorded in the central High Lava Plains, in western Harney Basin, three distinct mafic magmatic trends originate from primitive high-alumina olivine tholeiites (HAOT); they are tholeiitic, calcalkaline and ferro-trachytic. Tholeiitic basalts occur throughout the history and their compositions are derived by crystal fractionation while traversing the crust and mixing with evolved mafic magmas. Scavenging of apatite from crustal rocks and minor contamination with felsic melts accounts for …


Geochemistry And Geochronology Of The Central Metasedimentary Belt Boundary Thrust Zone Thrust Sheets In Southern Ontario, Grenville Province, Kenjo Agustsson 2012 California Polytechnic State University, San Luis Obispo

Geochemistry And Geochronology Of The Central Metasedimentary Belt Boundary Thrust Zone Thrust Sheets In Southern Ontario, Grenville Province, Kenjo Agustsson

Natural Resources Management and Environmental Sciences

Studies of pre-Grenvillian (1.4–1.3 Ga) plutons offer insight into the dynamics of arc amalgamation and backarc rifting prior to continental collision in the Ottawan orogeny. The Central Metasedimentary Belt boundary thrust zone (CMBbtz) is a northeast–southwest trending thrust zone consisting of metaplutonic thrust sheets enveloped in gneissic tectonites and calcitic– dolomitic marbles. Tonalitic CMBbtz thrust sheets (Dysart and Redstone) are made up of upper amphibolite-facies, foliation-concordant metatonalites (+ amphibole ± biotite ± accessory zircon and titanite) and amphibolites (± biotite ± clinopyroxene), and are located in the southern Ontario Grenville Province. These thrust sheets are thought to have formed and …


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