Geology Commons^™

Dendrochronological Analysis Of The Austin House

Historic Structures

Dating historical structures using dendrochronology. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: McGrath, Sarah; Reinthal, Mary; Starr, Kaitlin; Wiesenberg, Nicholas; Wiles, Greg

Sand Sea Extents And Sediment Volumes On Titan From Dune Parameters, Karl D. Arnold

Theses and Dissertations

Linear dunes are one of the most abundant and important features on the surface of Titan. We present a model for estimating the volume of dune sediment using the area coverage of Titan's sand seas along with dune widths, spacings, and heights. This helps to reveal local sediment transport and deposition. We refine global dune area estimates from Cassini SAR (Synthetic Aperture RADAR) of 20 million km2 or 24 ± 3% of Titan's surface based on ~50% Cassini RADAR global coverage. Additionally, the global area of sand seas is estimated from a joint analysis of Cassini SAR and ISS (Imaging …

Complex Thermal Histories Of L Melt Breccias Nwa 5964 And Nwa 6580, Kristy Lee Schepker

Dissertations and Theses

To constrain the thermal histories of two complex L chondrite melt breccia samples (NWA 5964 and NWA 6580) we compare textures and chemical compositions of metal and sulfide to L melt rock (NWA 6454 and NWA 6579) and strongly shocked (shock stage S6) (NWA 4860) samples. The inferred thermal histories can be used to evaluate formation settings on the L chondrite parent body. The L melt samples probably formed as different melt units within warm but largely unmelted material relatively close to the surface of the parent body, and the same is true for the S6 sample, except it experienced …

Along Strike Variability Of Thrust-Fault Vergence, Scott Royal Greenhalgh

Theses and Dissertations

The kinematic evolution and along-strike variation in contractional deformation in overthrust belts are poorly understood, especially in three dimensions. The Sevier-age Cordilleran overthrust belt of southwestern Wyoming, with its abundance of subsurface data, provides an ideal laboratory to study how this deformation varies along the strike of the belt. We have performed a detailed structural interpretation of dual vergent thrusts based on a 3D seismic survey along the Wyoming salient of the Cordilleran overthrust belt (Big Piney-LaBarge field). The complex evolution of the thrust faults that parallel the overthrust belt is demonstrated by the switching of the direction of thrust …

A New Geophysical Strategy For Measuring The Thickness Of The Critical Zone, Johnathan R. Yaede

Theses and Dissertations

Estimates of the depth and variation of lateritic weathering profiles are especially important in tropical areas such as Oahu, HI. Shear-wave velocity data were obtained by a new application of Multi-channel Analysis of Surface Waves (MASW) to map the base of the critical zone, to show variations in the LWP, and to derive weathering rates. The MASW technique proved highly capable of imaging the base of the critical zone, confirmed by lithological well data and direct field measurements. Profile thickness can be obtained without drilling, which has applications in engineering and geochemical studies. The measured rate of advance of the …

Facies Analysis, Sequence Stratigraphy And Paleogeography Of The Middle Jurassic (Callovian) Entrada Sandstone: Traps, Tectonics, And Analog, George R. Jennings Iii

Theses and Dissertations

The late Middle Jurassic (Callovian) Entrada Sandstone has been divided into two general facies associations consisting primarily of eolian sandstones in eastern Utah and "muddy" redbeds in central Utah. Sedimentary structures within the redbed portion are explained by the interfingering of inland sabkha, alluvial, and eolian depositional systems. A complete succession from the most basinward facies to the most terrestrial facies in the Entrada Sandstone consists of inland sabkha facies overlain by either alluvial or eolian facies. Where both alluvial and eolian facies interfinger, alluvial facies overlain by eolian facies is considered a normal succession. Sequence boundaries, often identified by …

Investigating Meter Scale Topographic Variation As A Factor Of Monterey Pine (Pinus Radiata) Growing Conditions At Kenneth Norris Rancho Marino Reserve, Cambria, Ca, William J. Meyst

Natural Resources Management and Environmental Sciences

Endemic Monterey pine (Pinus radiata) is limited to three locations in California due to its unique ecological requirements. This project was conducted to investigate spatial growth patterns ofMonterey pine over complex ground surfaces. The coastal hills of Rancho Marino Reserve, Cambria, were surveyed using four 150-m transects to quantify and record ground surface features and growing conditions ofMonterey pine. Changes in elevation of each transect were measured using an Abney level. Linear ground surfaces were found at 86% (344 of 400) of survey nodes. Convex ground surfaces were found at 10.5% of survey nodes (42 of 400). Of …

The University Of Nebraska State Museum, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

I first walked through the doors of Morrill Hall on the main or City Campus of the University of Nebraska on a day late in August of 1962 and thought that I had entered paleontology heaven. Morrill Hall then housed the University of Nebraska State Museum (UNSM). most of the Geology Department, and some other parts of university units. I was a new graduate student hoping to pursue research in invertebrate paleontology in the Department of Geology and was on my way to see the department chairman for the first time. When I entered the building I walked through a …

Dust And Pleistocene Ice Ages: Eolian Sediments And Climate Change At Ziegler Reservoir, Snowmass Village, Colorado, Jeffrey S. Honke

Electronic Theses and Dissertations

The discovery of the Ziegler Reservoir fossil site near Snowmass Village, Colorado presents an opportunity to examine subalpine ecosystem response, during a relatively unknown period, in which climate conditions were similar to present. Finegrained sediments at Ziegler Reservoir represent continuous deposition between ~140–55 ka (thousand years before present), spanning the close of the Bull Lake glacial period [marine isotope stage (MIS) 6], the Sangamon interglacial (MIS 5) and the early stages of the Pinedale (early Wisconsin) glacial period (MIS 4). Ziegler Reservoir is positioned on top of a ridge, at an elevation of 2705 m, and has a small watershed …

Detrital Zircon Geochemistry Of The Nacimiento Block, Santa Ynez Mountains, California, Vincent Zhao

Natural Resources Management and Environmental Sciences

The long-lived California section of the North American Cordillera is one of the most studied continental margins in the world; however, erosion and deformation in areas along the San Andreas Fault and the Sur-Nacimiento Fault has erased sections of the Cordillera which could provide insight in Cordilleran processes. The lost sections are partially preserved in detrital zircons deposited alongside the arc in fore-arc basins such as in the Toro Formation of the Nacimiento block which represents the coastal central California equivalent to the Great Valley Group, located in the Santa Ynez Mountains. Geochemical analysis of the detrital zircons from the …

The Capacity Of Hydrous Fluids To Transport And Fractionate Incompatible Elements And Metals Within The Earth's Mantle, John Adam, Marek Locmelis, Juan Carlos Afonso, Tracy Rushmer, Marco L. Fiorentini

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Both silicate melts and aqueous fluids are thought to play critical roles in the chemical differentiation of the Earth's crust and mantle. Yet their relative effects are poorly constrained. We have addressed this issue by measuring partition coefficients for 50 trace and minor elements in experimentally produced aqueous fluids, coexisting basanite melts, and peridotite minerals. The experiments were conducted at 1.0-4.0 GPa and 950-1200°C in single capsules containing (either 40 or 50 wt %) H₂O and trace element-enriched basanite glass. This allowed run products to be easily identified and analyzed by a combination of electron microprobe and LAM-ICP-MS. …

Sex-Biased Gene Flow Among Elk In The Greater Yellowstone Ecosystem, Brian K. Hand, Shanyuan Chen, Neil Anderson, Albano Beja-Pereira, Paul C. Cross, Michael Ebinger, Hank Edwards, Robert A. Garrott, Marty D. Kardos, Matt Kauffman, Erin L. Landguth, Arthur Middleton, Brandon Scurlock, P.J. White, Pete Zager, Michael K. Schwartz, Gordon Luikart

United States Geological Survey: Staff Publications

We quantified patterns of population genetic structure to help understand gene flow among elk populations across the Greater Yellowstone Ecosystem. We sequenced 596 base pairs of the mitochondrial control region of 380 elk from eight populations. Analysis revealed high mitochondrial DNA variation within populations, averaging 13.0 haplotypes with high mean gene diversity (0.85). The genetic differentiation among populations for mitochondrial DNA was relatively high (FST = 0.161; P = 0.001) compared to genetic differentiation for nuclear microsatellite data (FST = 0.002; P = 0.332), which suggested relatively low female gene flow among populations. The estimated ratio of male to female …

The Bell Springs Formation: Characterization And Correlationof Upper Triassic Strata In Northeast Utah, Skyler Bart May

Theses and Dissertations

Upper Triassic strata that lie between the Chinle Formation and Nugget Sandstone along the south flank of the Uinta Mountains in northeastern Utah are distinctive. In the past, these rocks have been lumped together with the overlying or underlying units. These strata are equivalent to the Bell Springs Member of the Nugget Sandstone as defined in Wyoming and perhaps to the Rock Point Formation of the Chinle Formation near the Four Corners region. In this study, these rocks will be called the Bell Springs Formation following the usage of Lucas (1993) in Wyoming. The unit is regionally mappable in northeastern …

Late Quaternary Faulting History Of The Carrizal And Related Faults, La Paz Region, Baja California Sur, Mexico, Paul J. Umhoefer, Sara J. Maloney, Beverly Buchanan, J. Ramón Arrowsmith, Genaro Martinez-Gutiérrez, Graham Kent, Neal Driscoll, Alistair Harding, Darrell Kaufman, Tammy M. Rittenour

Geosciences Faculty Publications

The southwest margin of the Gulf of California has an array of active normal faults despite this being an oblique-divergent plate boundary with spreading centers that localized deformation along the plate boundary 2–3 million years ago. The Carrizal and Centenario faults form the western border fault of the Gulf of California marginal fault system within and south of La Paz Bay, and ∼20–30 km west of the capital city of La Paz, Baja California Sur, Mexico. Geologic and geomorphic mapping, optically stimulated luminescence (OSL) geochronology, and paleoseismic investigations onshore, compressed high-intensity radar pulse (CHIRP) profiling offshore, and analysis of uplifted …

Co2 Sequestration Test In A Deep, Unminable Lignite Seam, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet describing results of a Plains CO₂ Reduction (PCOR) Partnership-implemented test to determine the possibility of storing CO₂ in unminable lignite seams. Discusses testing procedure and purpose, and summarizes key results. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]

Correlation And Paleoenvironments Above West T9.3 Tuff, Pisco Formation, Peru, Caleb Stanton

Loma Linda University Electronic Theses, Dissertations & Projects

The Pisco Basin is a Cenozoic forearc basin in west central Peru. Though outcrops are well exposed, contain little diagenetic overprint, or complex structural deformation, only rudimentary correlations between outcrops are published and no attempts have been made to define time-bounded subunits. The goal of this study is to develop high resolution-stratigraphy and paleoenvironmental interpretations for a time-bounded unit in the lower part of the Miocene Pisco Formation. In this study, we correlated, mapped, and dated a tuff couplet and associated beds over 25 km2. We measured eight sections that include the tuffs and conducted detailed facies analysis. Sections were …

Sedimentological And Stratigraphic Study Of A Falling-Stage Delta Complex In The Upper Cretaceous (Turonian) Ferron Sandstone Member Of The Mancos Shale, South-Central Utah, Usa, Fares Alaboud

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

The character and distribution of lithofacies in falling-stage deltas are incompletely documented. This paper presents a sedimentological and stratigraphic evaluation of a superbly-exposed interval of Cretaceous deltaic strata that are believed to be of falling stage origin. The studied interval forms part of the Upper Cretaceous (Turonian) Ferron Sandstone Member of the Mancos Shale in the southernmost Henry Mountains Basin of south-central Utah, USA. The interval of interest is exposed in three dimensions over a 20 km² area in a series of canyon walls. Observed facies include fine-grained mudrocks (offshore basin), mudrocks with thinly interlaminated sandstone (prodelta), thinly interbedded …

Watershed And Aquatic Ecosystem Evolution During The Late-Glacial And Early-Holocene Inferred From High-Resolution Diatom And Geochemical Records In The Yellowstone Region, Yanbin Lu

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

High-resolution diatom records spanning the late-glacial and early-Holocene were developed from three lakes in the Yellowstone region to infer the lake history and to evaluate the relative importance of climatic versus non-climatic factors on the aquatic ecosystem evolution. Synchronous shifts in diatom community structure occurred in all lakes, which are located in regions of varied surficial geology and precipitation seasonality, in the intervals of 13.9-13.8, 13.2-13.1, 11.3-11.0 and 8.8-8.7 cal ka. The synchronous diatom community structure shifts suggest that large-scale climatic change is the primary driver of the aquatic ecosystem evolution in this region, whereas the influence of non-climatic factors …

Origin And Distribution Of The Mississippian–Pennsylvanian Boundary Unconformity In Marine Carbonate Successions With A Case Study Of The Karst Development Atop The Madison Formation In The Bighorn Basin, Wyoming, Lucien Nana Yobo

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

The causal mechanism of the widespread unconformity that encompasses the Mississippian – Pennsylvanian boundary remains poorly understood. This unconformity, first thought to be restricted to North America, is now known to be present in other regions of the globe. Possible causes for the unconformity include (1) sea level draw down from the onset of glaciation at start of the late Paleozoic ice age and (2) increased tectonic activity from the formation of the supercontinent of Pangea. Thus the origin of the unconformity is still poorly constrained.

This study examines possible causal mechanisms for the widespread unconformity that encompasses the Mississippian …

Exploring The Link Between Otolith Growth And Function Along The Biological Continuum In The Context Of Ocean Acidification, Eric D. Wilcox Freeburg

Graduate Doctoral Dissertations

Oceans are acidifying as atmospheric CO₂ is drawn down. This process, known as ocean acidification (OA), is well known and documented. Over the next 100 years, pH of the surface ocean is projected to decrease by up to 0.35 units. This CO₂ draw down has a direct effect on dissolved inorganic carbon (DIC) balance in the ocean. OA is expected to impact calcifying organisms that rely on constituencies of the DIC system, specifically carbonate ion [CO₃2-]. It is clear that externally calcified structures, such as coral skeletons, bivalve shells, etc., will be significantly affected as pH, …