Geology Commons^™

Book Review: Stars Above, Earth Below: A Guide To Astronomy In The National Parks, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Stars Above, Earth Below : a Guide to Astronomy in the National Parks by Tyler Nordgren. Springer/Praxis, 2010 444p, 9781441916488 $29.95.

Upper Cretaceous Peay Bentonites (North-Central Wyoming): Provenance And Tectonics Interpretation From Ash Composition, Nazrul I. Khandaker, Carl F. Vondra, Karl E. Seifert, Malek Shami, Rochelle Cardinale, Thakur Chaturgan

Publications and Research

The Peay bentonites belong to the basal Frontier Formation (Bighorn Basin, north-central Wyoming), primarily outcrop in the Bighorn Basin, rest on an extensively bioturbated sandstone unit, the Peay Sandstone, and are generally the thinner bentonitic unit. Beds of very light gray to greenish gray bentonite are also abundant in the lower Frontier units between Kaycee and Mayoworth (Powder River Basin) and are very rarely as much as 3 m thick. Bentonite occurs within the interstratified shale, sandstone, and siltstone sequences of the lower Frontier unit throughout much of the southwestern Powder River Basin. The purpose of this study is to …

Bedrock Erosion By Root Fracture And Tree Throw: A Coupled Biogeomorphic Model To Explore The Humped Soil Production Function And The Persistence Of Hillslope Soils, Emmanuel Gabet, Simon Mudd

Faculty Publications

In 1877, G. K. Gilbert reasoned that bedrock erosion is maximized under an intermediate soil thickness and declines as soils become thinner or thicker. Subsequent analyses of this “humped” functional relationship proposed that thin soils are unstable and that perturbations in soil thickness would lead to runaway thinning or thickening of the soil. To explore this issue, we developed a numerical model that simulates the physical weathering of bedrock by root fracture and tree throw. The coupled biogeomorphic model combines data on conifer population dynamics, rootwad volumes, tree throw frequency, and soil creep from the Pacific Northwest (USA). Although not …

Geogram 2010, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Experimental Estimation Of The Gpr Groundwave Sampling Depth, Katherine R. Grote, Taylor Crist, Crystal Nickel

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Monitoring near-surface soil water content is essential for efficient water management and for understanding hydrologic processes in soils. Ground-penetrating radar (GPR) groundwaves are an approach that can be used to monitor the near-surface soil water content, but the efficacy of this technique is currently limited by the uncertainty surrounding the groundwave sampling depth. This research experimentally determines the sampling depth of GPR groundwaves under dry and saturated conditions in a sandy soil. Data were acquired using 250, 500, and 1000 MHz antennas within an experimental tank containing soil layers of contrasting electromagnetic velocities. Results show that the groundwave sampling depth …

Comparison Of Ice Core Dissolved Organic Matter From A Greenland Ice Core By Nanospray Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, Joshua Jeremiah Shiloh Marsh

Chemistry & Biochemistry Theses & Dissertations

Recent studies of ice cores have embarked on the task of determining the classes of dissolved organic matter (DOM) present in melt-water from the cores collected in numerous locations in the northern and southern hemispheres. This DOM originally derives from wet precipitation and is thought to reflect atmospheric organic matter derived from anthropogenic and non-anthropogenic sources. Because the amount of DOM is so low, previous studies have necessarily used large sample volumes (greater than 500 mL) to concentrate sufficient ice core DOM necessary for mass spectral analysis. Solid phase extraction (SPE) with C₁₈ resins was followed by evaporative concentration …

Geospatial Data Portals: Librarians Add Expertise In The Development Of Gis Metadata Catalogs, Adonna Fleming

University of Nebraska-Lincoln Libraries: Faculty Publications

Searching a geospatial data catalog can be frustrating for many GIS data users. Geospatial data catalogs are built on records created to a specific metadata standard, such as ISO 19115. The search query is often limited to searching a few tags within the record, such as title, publisher, spatial extent, content theme, and content type. GIS personnel tend to create metadata records with little thought into how it will be discovered by others. On the other hand, library catalogs are developed for a broad spectrum of users with varying knowledge of the subject. Librarians can bring this expertise in creating …

A Trekker’S Guide To The Khumbu Himalaya: Trailside Geology Along The Everest Base Camp Trek, Brigit Anderson

Independent Study Project (ISP) Collection

The Himalaya is the youngest and highest mountain range in the world. It thus provides a wonderful field lab for studying the mountain building process in action. The trek in the Khumbu (northeastern Nepal) from Lukla to Everest Base Camp takes you through the Higher Himalaya and some interesting geological features. This project gives an introduction to the larger Himalaya geology and more specifically geology of the Khumbu Region. It then follows the Lukla-Everest Base Camp (EBC) trekking route pointing out interesting geologic features along the way. Some of the concepts explained in this project are somewhat technical. For this …

Sensitivity Of Geoelectrical Measurements To The Presence Of Bacteria In Porous Media, Gamal Z. Abdel Aal, Estella A. Atekwana, Silvia Rossbach, D. Dale Werkema

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

We investigated the sensitivity of low-frequency electrical measurements (0.1-1000 Hz) to (1) microbial cell density, (2) live and dead cells, and (3) microbial attachment onto mineral surfaces of clean quartz sands and iron oxide-coated sands. Three strains of Pseudomonas aeruginosa PAO1 (wild type and rhlA and pilA mutant) with different motility and attachment properties were used. Varying concentrations of both live and dead cells of P. aeruginosa wild type in sand columns showed no effect on the real conductivity component (σ′). However, the imaginary conductivity component (σ″) increased linearly with increasing concentrations of live cells in sand columns, whereas minimal …

Characterization Of Soil Water Content Variability And Soil Texture Using Gpr Groundwave Techniques, Katherine R. Grote, Cale T. Anger, Bridget Kelly, Susan Sharpless Hubbard, Yoram N. Rubin

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Accurate characterization of near-surface soil water content is vital for guiding agricultural management decisions and for reducing the potential negative environmental impacts of agriculture. Characterizing the near-surface soil water content can be difficult, as this parameter is often both spatially and temporally variable, and obtaining sufficient measurements to describe the heterogeneity can be prohibitively expensive. Understanding the spatial correlation of near-surface soil water content can help optimize data acquisition and improve understanding of the processes controlling soil water content at the field scale. In this study, ground penetrating radar (GPR) methods were used to characterize the spatial correlation of water …

Design Of A Conditioner For Smoothing Wind Turbine Output Power, Murali Bottu, Mariesa Crow, A. Curt Elmore

Electrical and Computer Engineering Faculty Research & Creative Works

As a result of wind speed intermittency, highly variable wind power output can adversely impact local loads. We propose a conditioner to smooth the variable wind power by utilizing the energy of an ultracapacitor. The conditioner is based on a single phase voltage source inverter (VSI) connected between the grid interconnection point and the ultracapacitor. The shunt VSI injects or absorbs active power from the line to smooth the wind power by utilizing the short term storage capabilities of the ultracapacitor. The ultracapacitor is connected to the DC link through a DC-DC converter, which maintains the voltage of the DC …

Great Basin Center For Geothermal Energy, Wendy Calvin

Nevada Renewable Energy Consortium Meeting

The second annual Nevada Renewable Energy Consortium meeting took place at UNLV on August 20. The meeting focused on the current three NVREC program areas: Solar, Biomass and Geothermal. Presentations were made by participating entities and a poster session followed.

Chronostratigraphy And Paleontology Of The Mid-Cretaceous Wayan Formation Of Eastern Idaho, With A Description Of The First Oryctodromeus Specimens From Idaho, Laurel J. Krumenacker

Theses and Dissertations

The mid-Cretaceous Wayan Formation of Idaho consists of floodplain-deposited siltstones and mudstones, with subordinate fluvial sandstones and conglomerates. Deposition occurred in a tectonic foredeep at the toe of the Sevier thrust complex. Measurement of two incomplete and one complete section indicates a thickness of roughly 1,344 meters in the study area. No laterally extensive marker beds are present but the lower Wayan contains distinct chert pebble conglomerates, and the middle Wayan may contain a higher relative abundance of fluvial sandstone. Known fossil localities are limited to the lower and middle portions of the formation. The Wayan Formation, as currently defined, …

Secondary Enrichment Of Copper At The Madison Gold Skarn Deposit, Silver Star District, Montana, Christopher H. Gammons, Jill Sotendahl, Dan Everett

Geological Engineering

Secondary Enrichment of Copper at the Madison Gold Skarn Deposit, Silver Star District, Montana. This paper focuses on the chemical reactions responsible for secondary enrichment of copper...we argue that most of the secondary Cu enrichment occurred during a late hydrothermal event that replaced the high temperature skarn mineral assemblage with hematitic jasperoid. Evidence favoring this "hypogene" Cu enrichment hypothesis is presented.

Spatial Variations Of Crustal Characteristics Beneath The Hoggar Swell, Algeria, Revealed By Systematic Analyses Of Receiver Functions From A Single Seismic Station, Kelly H. Liu, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Hoggar swell in Algeria is one of the significant massifs of northwest Africa. The paucity of high-resolution geophysical studies of the crust and mantle beneath the massifs is mostly responsible for the heated debates about the depth of the source region of the Cenozoic volcanism and the closely related uncertainty about the mechanism that formed and maintains the high elevation of the swells. Here we report results from a systematic study of 1386 high-quality receiver functions (RFs) recorded by station TAM, the only permanent broadband seismic station on the Hoggar swell. The resulting crustal thickness is about 34 km …

Clay Mineral Cycles Identified By Diffuse Spectral Reflectance In Quaternary Sediments From The Northwind Ridge: Implications For Glacial-Interglacial Sedimentation Patterns In The Arctic Ocean, Lyanne N. Yurco, Joseph D. Ortiz, Leonid Polyak, Dennis A. Darby, Kevin A. Crawford

OES Faculty Publications

A Quaternary record of fine-grained sediment composition is used to investigate Arctic Ocean climate variability on glacial-interglacial time scales. Diffuse spectral reflectance data from sediment core P1-92AR-P25 from the Northwind Ridge, north of Alaska, demonstrates cyclic variations in mineralogy. Varimax-rotated R-mode factor analysis of down-core data revealed three major mineralogical assemblages, which were then compared with the content of manganese, a proxy for basin ventilation, and thus glacial-interglacial cycles. Results indicate that factor 1, a smectite + chlorite clay assemblage, was delivered to the core site during interglacials, either by fluvial discharge or sea-ice drift from Siberian rivers or inflow …

Thermal History Of The Ecstall Pluton From 40Ar/39Ar Geochronology And Thermal Modeling, Sarah J. Brownlee, Paul R. Renne

Environmental Science and Geology Faculty Research Publications

New ⁴⁰Ar/³⁹Ar thermochronology results and thermal modeling support the hypothesis of Hollister et al. (2004), that reheating of the mid-Cretaceous Ecstall pluton by intrusion of the Coast Mountains Batholith (CMB) was responsible for spatially variable remagnetization of the Ecstall pluton. ⁴⁰Ar/³⁹Ar ages from hornblende and biotite from 12 locations along the Skeena River across the northern part of the Ecstall pluton decrease with proximity to the Quottoon plutonic complex, the nearest member of the CMB to the Ecstall pluton. The oldest ⁴⁰Ar/³⁹Ar ages are found farthest from the Quottoon plutonic …

Hydromechanical Interference Slug Tests In A Fractured Biotite Gneiss, Trever Slack

All Theses

Fractures are ubiquitous in the shallow crust and they commonly control the flow and storage of fluids in rock. Estimating transmission and storage properties resulting from fractures is commonly accomplished by interpreting the pressure signals caused by stressing an aquifer during a pumping or slug test. Fractures deform in response to pressure changes during well tests, and measuring and interpreting the deformation along with the pressure change is a way to potentially increase the information about storage and transmission properties. Tests where the pressure and deformation are coupled are called hydromechanical well tests. Previous investigations have focused on the effects …

The Effects Of Contact Metamorphism On The Host Rocks For Carlin-Type Mineralization At The Getchell Development, Nevada, Usa, Nathan C. Eck

UNLV Theses, Dissertations, Professional Papers, and Capstones

Carlin-type gold deposits (CTGDs) result from low to moderate temperature hydrothermal systems which form replacement bodies in carbonate or calcareous host rocks. The Getchell CTGD is located on the Getchell trend in north central Nevada. The Eocene age mineralization is locally hosted within the metamorphic aureole of the Cretaceous age Osgood stock. Previous studies have noted that the effects of the contact metamorphism can be heterogeneous, with strongly calc-silicate altered carbonates transitioning to relatively pristine limestone over short distances. The main finding of this study was that the variability in calc-silicate alteration is largely dependent on the differing host lithologies …

Physical And Chemical Properties Of Ice In A Main Valley Glacier And A Tributary Glacier, Gornergletscher, Canton Valais, Switzerland, Annika M. Quick

Theses and Dissertations

Glacier models often fail to incorporate the geometry and/or physical properties of tributaries included in complex glaciers. Tributary glaciers have different source areas and flow conditions than the adjacent main valley glacier. Ice cores (~3m depth) and surface samples (<0.5m depth) were collected from Grenzgletscher (main valley glacier) and Zwillingsgletscher (tributary glacier) in the Gornergletscher system of the Swiss Alps. Stable water isotopes indicate seasonal variation, showing 1-2 annual layers. The mean d18O for Grenzgletscher is ~4.8‰ lower than for Zwillingsgletscher. This difference may be accounted for in part by elevation differences between the accumulation areas (~1.1‰ δ18O), increased avalanching in Grenzgletscher (~1.8 ‰ δ18O), and by varying climatic conditions at the time of precipitation (~0.9-1.4‰ variation in δ18O). Using a kinematic ice flow model, core ages were estimated using effective annual layer thickness (based on seasonal variations), annual accumulation rate and ice thickness. The Grenzgletscher core is ~4 years older than the Zwillingsgletscher core. Based on ages and flow distances, the tributary has a lower flow velocity (63-87 m/yr) compared to Grenzgletscher (61-134 m/yr). To understand thermal properties of the tributary, a 775 m GPR survey (200 MHz) was conducted along a flow line of Zwillingsgletscher. Topographic waves (ogives) observed on the surface are mimicked by the onset of reflectivity 10-20 m below the surface. Reflective regions are interpreted as warmer ice at the pressure melting point, overlain by colder ice. This thermal structure is likely related to acceleration through an ice fall. Since most tributary glaciers include ice falls, thermal properties of tributary glaciers may be different from those of the main valley glacier. The properties and geometry of tributary glaciers are significantly different from main valley glaciers and should therefore be incorporated into glacier models in the future.

The Toll Of Toxics: Investigating Environmental Contaminants, Donald Sparling, Barnett A. Rattner, John S. Barclay

United States Geological Survey: Staff Publications

Two recent events [the Deepwater Horizon oil spill and the Asarco settlement] bring to the fore the work of wildlife toxicologists. Focusing on amphibians, reptiles, birds, and mammals, wildlife toxicology is a component of ecotoxicology--the study of toxic effects caused by natural or synthetic pollutants on living organisms and other constituents of ecosystems (Truhaut 1977). Now a distinct discipline within the wildlife profession-practiced by members of The Wildlife Society's own Wildlife Toxicology Working Group, among others-wildlife toxicology has become increasingly important as human populations and industry have spread, causing contaminants to multiply.

Emerging Environmental Contaminants (EECs) include an array of …

Quantifying Vertical Axis Rotation In Curved Orogens: Correlating Multiple Data Sets With A Refined Weighted Least Squares Strike Test, Adolph Yonkee, Arlo Brandon Weil

Geology Faculty Research and Scholarship

Map-scale curvature is a fundamental feature of most contractional orogenic belts and is central to understanding the kinematic and dynamic evolution of mountain systems. Paleomagnetic analysis, combined with detailed structural studies, is the most robust means of quantifying vertical axis rotations that produce curvature over a range of temporal and spatial scales. This paper explores how vertical axis rotations can best be evaluated for multiple data sets by applying a weighted least squares method to the classic strike test. This refined method provides measures of best fit slope, confidence interval, and goodness of fit between map-scale structural trend, paleomagnetic rotations, …

Sediment Flux Through The Rio Grande River: A Monsoonal Effect, Troy C. Hiatt

Theses and Dissertations

Climate has historically been recognized as an influence on sediment flux and deposition. The North American Monsoon is suggested as the forcing mechanism of deltaic progradational events of the Rio Grande River delta. Interpretations of reflection seismic profiles reveal that eustatic rise in sea-level from the Last Glacial Maximum to present is accompanied by several regressional events of the Rio Grande delta 5.5, 9.5, and 11.5 ka BP. Much of the migration of depositional facies within a delta system is forced by hinterland tectonics and base-level rise and fall. However, we suggest that the movement of facies within the Rio …

Variable-Density Flow Models Of Saltwater Intrusion In Coastal Landforms In Response To Climate Change Induced Sea Level Rise And A Chapter On Time-Frequency Analysis Of Ground Penetrating Radar Signals, Swagata Guha

USF Tampa Graduate Theses and Dissertations

Populations residing on and near the world’s coasts have become increasingly dependent on coastal groundwater for their supply of freshwater. Under the conditions of predicted climate changes, the expected rise in global sea level can adversely affect the quality and quantity of freshwater resources in coastal areas as a result of saltwater intrusion.

In this study, a suite of two- and three-dimensional variable-density groundwater flow models of major coastal landforms (e.g. deltas, estuaries and small islands) has been constructed to assess the effects of sea level rise (SLR), using different SLR rates of 0.5 m, 1m and 1.5 m over …

Counterintuitive Consequence Of Heating In Strongly-Driven Intrinsic Junctions Of Bi₂Sr₂Cacu₂O8+Δ Mesas, Cihan Kurter, Lutfi Ozyuzer, Thomas Proslier, John F. Zasadzinski, David G. Hinks, Kenneth E. Gray

Physics Faculty Research & Creative Works

Anomalously high and sharp peaks in the conductance of intrinsic Josephson junctions in Bi₂ Sr₂ CaCu₂ O _8+δ (Bi2212) mesas have been commonly interpreted as superconducting energy gaps but here we show they are a result of strong self-heating. This conclusion follows directly from a comparison to the equilibrium gap measured by tunneling in single break junctions on equivalent crystals. As the number of junctions in the mesa, N, and thus heating increase, the peak voltages decrease and the peak width abruptly sharpens for N≥12. Clearly these widely variable features vs N cannot all represent the equilibrium …

Climatic Cycles Recorded In The Middle Eocene Hemipelagites From A Dinaric Foreland Basin Of Istria (Croatia), Borna Lužar-Oberiter, Peter A. Hochuli, Ljubomir Babić, Bosiljka Glumac, Darko Tibljas

Geosciences: Faculty Publications

Middle Eocene hemipelagic marls from the Pazin-Trieste Basin, a foreland basin of the Croatian Dinarides, display repetitive alternations of two types of marls with different resistance to weathering. This study focuses on the chemical composition, stable isotopes, and palynomorph content of these marls in order to better understand the nature of their cyclic deposition and to identify possible paleoenvironmental drivers responsible for their formation. The less resistant marls (LRM) have consistently lower carbonate content, lower δ18O and δ13C values, and more abundant dinoflagellate cysts than the more resistant marls (MRM). We interpret these differences between the two marl types to …

Glaciotectonic Deformation Along The Valparaiso Upland In Southwest Michigan, Usa, Brian C. Bird

Dissertations

Glaciotectonic deformation has been observed and analyzed across parts of the Valparaiso, Kendall, and Inner Kalamazoo Moraines in southwest Michigan, USA. Deformation structures such as folds and faults have been analyzed using techniques typically used by structural geologist along with the fabric of elongated clasts in the surficial diamicton. The structures are consistent with simple shear, horizontal compressional stresses, and pure shear. A series of drumlin fields exist along the western boundary of the study area. Direct investigation of the deformed sediments was conducted at a gravel pit in one of these drumlins. Lacustrine derived sediments interbedded with coarse sand …

Enrichments Of Heavy Sulfur (34s) In Sulfide Minerals: Gas Hydrates, Methane Delivery, And Anaerobic Methane Oxidation, Walter S. Borowski, Namcy M. Rodriguez, Charles K. Paull, William Ussler Iii

EKU Faculty and Staff Scholarship

The sulfur isotopic composition of authigenic, sedimentary sulfide minerals is largely controlled by sulfate reduction and related processes within sedimentary environments. Histograms show that that d³⁴S values of sulfide minerals forming in depositional and diagenetic environments are most often negative (d³⁴S < 0^o/_oo CDT) reflecting the original isotopic composition of seawater sulfate (now ~21^o/_oo), microbially-mediated fractionations of ~-8 to -40^o/_oo (a = 1.029-1.059) during sulfate reduction, and more extreme fractionations caused by sulfur disproportionation. Enrichments of heavy sulfur (d³⁴S > 0^o/_oo) in sulfide …

Mississippi Canyon 252 Incident Nrda Tier 1 For Deepwater Communities, Gregory Boland, Gary Brewer, Erik Cordes, Amanda Demopoulos, Chuek Fisher, Chris German, Ken Sulak

United States Geological Survey: Staff Publications

The northern Gulf of Mexico (GOM) is geologically diverse basin, described as the most complex continental slope region in the world. Regional topography of the slope consists of basins, knolls, ridges, and mounds derived from the dynamic adjustments of salt and the introduction of large volumes of sediment over long time scales. More than 99% of the sea floor in the GOM consists of soft sediment made up of various mixtures of primarily silt and clay. These wide-spread soft bottom communities are described in reports from major MMS studies by Gallaway et al. (1998) and Rowe and Kennicutt (2009). Relative …

Stratigraphy, Sedimentology, And Ichnology Of The Upper Cretaceous Frontier Formation In The Alkali Anticline Region, Bighorn County, Wyoming, Charles K. Clark

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The Upper Cretaceous Frontier Formation was studied along two strike-parallel cliff-lines in the Alkali Anticline region of the northeastern Bighorn Basin, Bighorn County, Wyoming. The unit comprises up to 145 m of mudrock, sandstone, conglomerate, and volcanic fallout sediments deposited along the western margin of the Cretaceous Western Interior Seaway (KWIS) in the mid- to late-Cenomanian. Eighteen facies, comprising six facies associations are identified from physical and biogenic sedimentary features. Sediments were deposited in open marine offshore to shoreface and subaqueous deltaic to delta platform environments. The observed trace fossil suites record departures from the archetypal ichnofacies. Such departures record …