Geology Commons^™

Revised Structure And Correlation Of The Great Salt Lake, North Promontory, Rozel And Hansel Valley Fault Zones Revealed By The 2015-2016 Low Stand Of Great Salt Lake, Susanne U. Jänecke, James P. Evans

Geosciences Faculty Publications

Years of drought conspired to produce the present historic low stand in Gunnison Bay of Great Salt Lake. The lake has receded enough to expose the Great Salt Lake fault zone, and reveal its geometry through the shallow and clear lake water. We mapped the newly visible escarpments along the fault zone, upgraded the Utah fault map, and revised the regional correlation of the Great Salt Lake, Rozel, and North Promontory fault zones. We explored the origin of wave-cut platforms in the footwall of the faults, and identify geometrically unique types of microbial communities along faults and fault-related springs and …

Preservation Of Sea Anemone Burrows In Silurian (~432 Million Years Old) Carbonate Rocks Of Southeastern Indiana, Usa, Marissa Tomin

Williams Honors College, Honors Research Projects

Preservation of trace fossils (ichnofossils) in siliciclastic environments is often quite different from preservation in carbonate environments, representing an important source of variation that must be well understood in order to enhance interpretations of paleoenvironments and paleoecology. This study focuses on Conostichus, a relatively common burrow constructed by solitary sea anemones. These trace fossils are generally well-preserved (i.e., they display detailed external features) in siliciclastic rocks but are typically little more than conical masses in carbonate rocks. However, certain specimens recovered from the middle Silurian Massie Formation at the Napoleon quarry of southeastern Indiana are composed entirely out of …

Constraining Times Of Extension In The Southern Rio Grande Rift And Basin And Range Using Apatite And Zircon (U-Th)/He Thermochronology, Julian Biddle

Open Access Theses & Dissertations

The Rio Grande rift and the Basin and Range are adjacent extensional domains that have evolved contemporaneously in western North America. Although the rift is often considered to be the easternmost boundary of Basin and Range extension, there is geologic and geophysical evidence that suggests the two are discrete provinces. Existing low-temperature thermochronologic data indicate that a period of synchronous extension occurred across the entire length of the rift from ~25-10 Ma. However, these studies were more focused on the northern and central sections of the rift, and thermochronologic data remains sparse in southern New Mexico. We collected rock samples …

A Quantitative Analysis Of The Fretted Terrain Valleys, Arabia Terra, Mars, Kelsey Anne Mason

Open Access Theses & Dissertations

Fretted terrain describes regions on Mars with low-lying, flat valleys separated by steep cliffs that often form polygonal-shaped mesas. The fretted terrain valleys have a morphology distinct from other valleys found on Mars, and their unknown origin may hold insights into critical questions about Mars' tectonic, magmatic, and hydrologic history. Current hypoThesis for the formation of the fretted terrain include fracturing as well as hydrological flow processes such as fluvial or glacial erosion. The region for this study is located in eastern Arabia Terra and is the type-location for fretted terrain. By qualitatively and quantitatively documenting the planform, or map-view, …

Airborne Lead In El Paso, Texas, Usa, Lisa Marie Paz

Open Access Theses & Dissertations

Despite significant strides to minimize lead in our air, water, soil, food, homes, workplaces, and consumer products, sporadic and systemic lead poisoning persists in industrial societies, e.g., the contemporary Flint (Michigan, USA) municipal water tragedy. Because lead exposure is cumulative, the sum of exposure from all sources, it is important to document and update potential community or neighborhood exposure levels from such environmental compartments as air, water, and housing. Here we present ambient airborne lead levels in El Paso, Texas, USA, parsed by particulate matter (PM) size fraction, geography, and season. Dichotomous samplers at 8 stations collected particulate matter continuously …

Cycling Of Gypsiferous White Sands Aerosols In The Shallow Critical Zone At White Mountain, New Mexico, Patrick Richard Rea

Open Access Theses & Dissertations

Dry deposition significantly affects evolution of the critical zone by nutrient supply and contributing to soil genesis. Dust influx and cycling in soils are difficult to quantify because dust sources can be chemically similar to local soils. White Sands, New Mexico, emits gypsum dust with a unique chemical and isotopic signature, providing an opportunity to investigate dust deposition and its movement in soils. This study evaluated the mobility of White Sands dust particles in the critical zone at White Mountain, New Mexico, a highland 100 km downwind. Four soil profiles were collected over limestone, igneous, mixed limestone and dolostone, and …

Near-Surface And High Resolution Seismic Imaging Of The Bennett Thrust Fault In The Indio Mountains Of West Texas, Alan Thomas Vennemann

Open Access Theses & Dissertations

My research investigates the structure of the Indio Mountains in southwest Texas, 34 kilometers southwest of Van Horn, at the UTEP (University of Texas at El Paso) Field Station using newly acquired active-source seismic data. The area is underlain by deformed Cretaceous sedimentary rocks that represent a transgressive sequence nearly 2 km in total stratigraphic thickness. The rocks were deposited in mid Cretaceous extensional basins and later contracted into fold-thrust structures during Laramide orogenesis. The stratigraphic sequence is an analog for similar areas that are ideal for pre-salt petroleum reservoirs, such as reservoirs off the coasts of Brazil and Angola …

Pressure Dependence Of Polycrystalline Magnesite And Dolomite, Cole Blasko

Williams Honors College, Honors Research Projects

Intermediate depth (170-400 km) deep focus earthquakes are observed in subducting slabs, but unlike shallow (50-170 km) and deep (400-660 km) deep focus earthquakes, the mechanism(s) responsible for them are not clear. Two common alteration products observed in peridotites, magnesite and dolomite, are stable along the pressure-temperature path of a subducting slab. Low pressure experiments indicate that these minerals are weaker than olivine, but there are no data about the pressure dependence of the strength of magnesite or dolomite. Magnesite and dolomite cylinders (1mm by 1mm) were deformed in stacked series to 25-30% strain using the deformation-DIA (DDIA) at Argonne …

Glacial Deposits, Vol. 42, 2017, Department Of Geography, Geology, And The Environment

Glacial Deposits

Newsletter of the Department of Geography, Geology, and the Environment

Mercury Increases In Lake Tanganyika Since ~1850, Troy A. Bole

Williams Honors College, Honors Research Projects

A series of three sediment cores were collected in Lake Tanganyika, Africa, and were analyzed for mercury concentrations. For all three cores, a decrease in mercury (Hg) levels was observed from the 1600’s (appx. 20 ng/g) until concentrations reached a minimum during the mid-1800’s (appx. 10 ng/g). The mid-1800’s marked a change from decreasing mercury levels to an increase over the following century. The core tops (circa 2006) have concentrations greater than 70 ng/g. The onset of the rise in mercury concentrations coincides with the beginning of the Industrial Revolution in the mid to late 18^th century. Relationships between …

Carbon Cycle Trends Recorded By Organic Carbon Stable Isotopes In Paleocene Strata, Benton County, Mississippi: Implications For Chronostratigraphy Of The Porters Creek And Naheola Formations, Erica Gerweck

Electronic Theses and Dissertations

The paleocene-eocene thermal maximum (petm) is one of the most studied carbon isotope excursions in earth's history. The petm occurred 55 million years ago when excess isotopically heavy carbon (c13) was added into earth's carbon cycle, resulting in ecological and environmental changes. The petm is marked by a negative stable carbon isotope excursion (cie) in marine and continental strata around the globe. The paleocene and eocene boundary is contained in the sedimentary fill of the Mississippi embayment so there is high potential to produce new petm stable isotope datasets. The purpose of this project is to analyze the boundary for …

Great Plains Geology, Robert F. Diffendal Jr.

University of Nebraska Press: Sample Books and Chapters

Great Plains Geology concisely guides readers through the geological development of the Great Plains region. It describes the distinct features of fifty-seven geologic sites, including fascinating places such as Raton Pass in Colorado and New Mexico, the Missouri Breaks of Montana, and the Ashfall Fossil Beds in Nebraska. This guide addresses the tricky question of what constitutes the Great Plains, showing that the region is defined in part through its unique geologic features.

Developing A Gis Tool For Infinite Slope Stability Analysis (Gis-Tissa), Jonathon Sanders

Dissertations, Master's Theses and Master's Reports

The Probabilistic Infinite Slope Analysis model (PISA-m) is a widely used computer program that uses infinite slope equations to calculate the spatially varying Factor of Safety of slopes. ESRI’s ArcGIS software and accompanying geoprocessing tools have become a mainstay in spatial data processing, and received full support for Python with the release of version 10. With many of the geoprocessing tools now available as a Python function, the software can be used for physics-based spatial landslide hazard analysis. A model that mimics PISA-m and its processing of normally distributed soil properties was created using the Python utility as a tool …

Drivers Of Sediment Accumulation And Nutrient Burial In Coastal South Carolina Residential Stormwater Detention Ponds, William Schroer

Theses and Dissertations

Stormwater detention ponds are widely utilized as control structures to manage runoff waters during storm events. These sediments also represent significant sites of organic carbon and nutrient burial. Here, carbon (C) and nutrient sources and burial rates were determined in 14 residential stormwater detention ponds throughout coastal counties of South Carolina. Bulk sediment accumulation was directly correlated with catchment impervious surface coverage (R2 = 0.90) with sediment accumulation rates ranging from 0.06 to 0.50 cm y-1. These rates of sediment accumulation and subsequent pond volume loss are lower than expected indicating that required maintenance dredging schedules be reassessed. Strong, positive …

Tectonic Studies Of Southeastern North America: The Suwannee Basin, Brunswick Suture Zone, Osceola Arc, And Pangean Transcurrent Fault System, Susannah Katherine Boote

Theses and Dissertations

A series of exotic terranes with complex tectonostratigraphic relationships construct the North American margin and record information critical to understanding the evolution of the Appalachian orogen. The Coastal Plain cover remains a challenge in this region; however, synthesis of seismic reflection, seismic refraction, well, and aeromagnetic data allows for a substantially revised interpretation of the basement rocks and structures that comprise the pre-Mesozoic crust of southeastern North America. These data reveal: (1) a Neoproterozoic subduction zone and paired continental-margin arc are preserved in Gondwanan crust in southeastern North America, (2) the Gondwanan Suwannee Basin of Early to Mid-Paleozoic age is …

High Resolution Gravity, Helicopter Magnetic, And Electromagnetic Study, Haile Gold Mine, South Carolina, Saad Saud Alarifi

Theses and Dissertations

The goal of this research was to calibrate and test geophysical methods for the detection of disseminated sulfides in the area of the Haile Gold Mine, South Carolina. The work focused on the calibration of high resolution gravity, and helicopter electromagnetic (EM) and magnetic data provided by OceanaGold. While high resolution potential field data (gravity and magnetics) has not been proven to be effective at small scales in exploration for disseminated sulfides, there is a strong regional correlation between high amplitude gravity and magnetic anomalies and the most productive gold mines in the Carolina terrane. Helicopter EM methods have been …

Quantifying Ephemeral Gully Erosion With Photogrammetry Surveying, C. B. Weerasekara, A. Y. Shechukov

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Review Of A Chorus Of Cranes: The Cranes Of North America And The World By Paul A. Johnsgard, Aaron T. Pearse

United States Geological Survey: Staff Publications

Cranes (Gruidae) are widely distributed throughout the world, have lived on Earth for several million years, and currently reside on five continents. Archaeological evidence and historical references suggest that humans have interacted with and been captivated by cranes for many thousands of years (e.g., Leslie 1988, Muellner 1990). A glimpse of our reverence for these birds can be found in A Chorus of Cranes by Paul A. Johnsgard, with photographs by Thomas D. Mangelsen. Many species of cranes are currently identified as threatened or endangered, and their future will likely rest in the hands of humans; this book presents their …

Variation In Δ15N And Δ13C Values Of Forages For Arctic Caribou: Effects Of Location, Phenology And Simulated Digestion, Lindsay L. Vansomeren, Perry S. Barboza, David D. Gustine, M. Syndonia Bret-Harte

United States Geological Survey: Staff Publications

RATIONALE: The use of stable isotopes for dietary estimates of wildlife assumes that there are consistent differences in isotopic ratios among diet items, and that the differences in these ratios between the diet item and the animal tissues (i.e., fractionation) are predictable. However, variation in isotopic ratios and fractionation of δ¹³C and δ¹⁵N values among locations, seasons, and forages are poorly described for arctic herbivores especially migratory species such as caribou (Rangifer tarandus).

METHODS: We measured the δ¹³Cand δ¹⁵N values of seven species of forage growing along a 200-km …

Assessment Of Frequency And Duration Of Point Counts When Surveying For Golden Eagle Presence, Ben R. Skipper, Clint W. Boal, Jo-Szu Tsai, Mark R. Fuller

United States Geological Survey: Staff Publications

We assessed the utility of the recommended golden eagle (Aquila chrysaetos) survey methodology in the U.S. Fish and Wildlife Service 2013 Eagle Conservation Plan Guidance. We conducted 800-m radius, 1-hr point-count surveys broken into 20-min segments, during 2 sampling periods in 3 areas within the Intermountain West of the United States over 2 consecutive breeding seasons during 2012 and 2013. Our goal was to measure the influence of different survey time intervals and sampling periods on detectability and use estimates of golden eagles among different locations. Our results suggest that a less intensive effort (i.e., survey duration shorter …