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A Spatio-Temporal Comparison Of Avian Migration Phenology Using Citizen Science Data, Ali Arab, Jason R. Courter, Jessica Zelt 2016 Georgetown University

A Spatio-Temporal Comparison Of Avian Migration Phenology Using Citizen Science Data, Ali Arab, Jason R. Courter, Jessica Zelt

United States Geological Survey: Staff Publications

The effects of climate change have wide-ranging impacts on wildlife species and recent studies indicate that birds’ spring arrival dates are advancing in response to changes in global climates. In this paper, we propose a spatio-temporal approach for comparing avian first arrival data for multiple species. As an example, we analyze spring arrival data for two long-distance migrants (Rubythroated Hummingbird Archilochus colubris; and Purple Martin Progne subis) in eastern North America from 2001–2010 using Citizen Science data. The proposed approach provides researchers with a tool to compare mean arrival dates while accounting for spatial and temporal variability. Our results show …


Phosphorus Retention In A Lowland Neotropical Stream Following An Eight-Year Enrichment Experiment, Gaston E. Small, Marcelo Ardón, John H. Duff, Alan P. Jackman, Alonso Ramírez, Frank J. Triska, Catherine M. Pringle 2016 University of St Thomas, St Paul

Phosphorus Retention In A Lowland Neotropical Stream Following An Eight-Year Enrichment Experiment, Gaston E. Small, Marcelo Ardón, John H. Duff, Alan P. Jackman, Alonso Ramírez, Frank J. Triska, Catherine M. Pringle

United States Geological Survey: Staff Publications

Human alteration of the global P cycle has led to widespread P loading in freshwater ecosystems. Much research has been devoted to the capacity of wetlands and lakes to serve as long-term sinks for P inputs from the watershed, but we know much less about the potential of headwater streams to serve in this role. We assessed storage and retention of P in biotic and abiotic compartments after an 8-y experimental P addition to a 1st-order stream in a Neotropical wet forest. Sediment P extractions indicated that nearly all P storage was in the form of Fe- and Al-bound P …


Cyclostratigraphy And Sedimentation Of The Cenomanian-Turonian Tuscaloosa Marine Shale, Christian Gilbert Kunhardt 2016 University of Mississippi

Cyclostratigraphy And Sedimentation Of The Cenomanian-Turonian Tuscaloosa Marine Shale, Christian Gilbert Kunhardt

Electronic Theses and Dissertations

A cyclostratigraphic and geochemical analysis was conducted on the basal high resistivity zone of the Tuscaloosa Marine Shale to determine if orbital forcing is apparent in mineralogical data suites. Geochemical data suites obtained via x-ray diffraction from five cored wells located near the southern Mississippi/Louisiana border were used in the study. The results were used in concert with previously published insolation and biostratigraphic data and unpublished stable carbon isotope data to determine sedimentation rate, to identify and correlate the cretaceous oceanic anoxic event 2 (OAE 2) recovery period within the studied interval, and to determine the possible mechanisms of orbital …


Portable X-Ray Fluorescence Measurement Viability In Organic Rich Soils: Pxrf Response As A Function Of Organic Matter Presence, Roozbeh Ravansari 2016 Wayne State University

Portable X-Ray Fluorescence Measurement Viability In Organic Rich Soils: Pxrf Response As A Function Of Organic Matter Presence, Roozbeh Ravansari

Wayne State University Theses

Portable X-Ray fluorescence provides a cost effective method for producing rapid geochemical data. With advancements in X-Ray generation and detection technology, pXRF has become feasible for use on pedologic materials. Factors affecting pXRF soil measurements such as heterogeneity, moisture content, object geometry, and matrix interferences are widely recognized. However, the influence of organic matter on pXRF soil measurements is poorly understood.

This study examined the influence of organic matter fraction on pXRF trace metal measurements in a soil matrix. Incremental addition of three organic matter surrogates (cellulose, graphite powder, and confectioner’s sugar) was used to investigate the influence of increasing …


Integration Of Deterministic And Stochastic Models In A 1,4-Dioxane Contaminated Glacial Aquifer System, Washtenaw County, Michigan, Lena Kristin Pappas 2016 Wayne State University

Integration Of Deterministic And Stochastic Models In A 1,4-Dioxane Contaminated Glacial Aquifer System, Washtenaw County, Michigan, Lena Kristin Pappas

Wayne State University Theses

Hybrid models incorporating stochastic variability within a deterministic hydrostratigraphic framework provide an effective way to assess uncertainty in flow and transport model predictions. This study evaluated the distribution of groundwater flow and contaminant transport pathways in two ensembles of spatially variable hydraulic conductivity (K) distributions. The models comprised a 360 ft-thick sequence of Pleistocene glacial sediments in in an approximately 8 mi2 area across Washtenaw County, Michigan. Conditioned K fields were generated using Sequential Gaussian Simulation (SGS) and Sequential Indicator Simulation (SIS) constructed using indicator classes based on natural gamma ray logs from 77 monitoring wells. K fields were modeled …


Site Characteristics, Instrumentation, And Recordings Of The Central United States Seismic Observatory, Edward W. Woolery, Zhenming Wang, N. Seth Carpenter 2016 University of Kentucky

Site Characteristics, Instrumentation, And Recordings Of The Central United States Seismic Observatory, Edward W. Woolery, Zhenming Wang, N. Seth Carpenter

Report of Investigations--KGS

The Central United States Seismic Observatory is a vertical seismic array in southwestern Kentucky within the New Madrid Seismic Zone. It is intended to record the effects of local geology, including thick sediment overburden, on seismic-wave propagation, particularly strong ground motion. The three-borehole array is composed of seismic sensors placed on the surface, in the bedrock, and at various depths within the 585-m-thick sediment overburden. The array's deep borehole also provides a unique opportunity to describe the geology and geophysically measure the complete Late Cretaceous through Quaternary stratigraphy in the northern Mississippi Embayment.

Based on the surface and borehole geophysical …


Encrustation Of Inarticulate Brachiopods On Scaphitid Ammonites And Inoceramid Bivalves From The Upper Cretaceous U. S. Western Interior, Neil H. Landman, Joshua S. Slattery, Peter J. Harries 2016 American Museum of Natural History

Encrustation Of Inarticulate Brachiopods On Scaphitid Ammonites And Inoceramid Bivalves From The Upper Cretaceous U. S. Western Interior, Neil H. Landman, Joshua S. Slattery, Peter J. Harries

School of Geosciences Faculty and Staff Publications

The inarticulate brachiopod Discinisca is a rare faunal element in the Upper Cretaceous of the U.S. Western Interior. We report two occurrences of encrustation of Discinisca on a scaphitid ammonite (scaphite) and several inoceramids from the lower Maastrichtian Baculites baculus/Endocostea typica Biozones of the Pierre Shale at two localities. Six specimens of Discinisca are present on a single specimen of Hoploscaphites crassus from east-central Montana. They occur along the furrow at the mature apertural margin. Because the brachiopods are restricted to the margin and do not occur on the rest of the shell, it is likely that they …


A Fossilized Energy Distribution Of Lightning, Matthew A. Pasek, Marc Hurst 2016 University of South Florida

A Fossilized Energy Distribution Of Lightning, Matthew A. Pasek, Marc Hurst

School of Geosciences Faculty and Staff Publications

When lightning strikes soil, it may generate a cylindrical tube of glass known as a fulgurite. The morphology of a fulgurite is ultimately a consequence of the energy of the lightning strike that formed it, and hence fulgurites may be useful in elucidating the energy distribution frequency of cloud-to-ground lightning. Fulgurites from sand mines in Polk County, Florida, USA were collected and analyzed to determine morphologic properties. Here we show that the energy per unit length of lightning strikes within quartz sand has a geometric mean of ~1.0 MJ/m, and that the distribution is lognormal with respect to energy per …


Controls On Carbonate Sedimentation And Sequence Stratigraphic Framework Of The Lower Permian (Wolfcampian) Hueco Formation (Upper-Middle And Gastropod Intervals), Robledo Shelf, Western Orogrande Basin, New Mexico, Matthew S. Harder 2016 University of Texas at El Paso

Controls On Carbonate Sedimentation And Sequence Stratigraphic Framework Of The Lower Permian (Wolfcampian) Hueco Formation (Upper-Middle And Gastropod Intervals), Robledo Shelf, Western Orogrande Basin, New Mexico, Matthew S. Harder

Open Access Theses & Dissertations

On the western margin of the Pennsylvanian/Permian Orogrande Basin, two composite measured sections in the Lower Permian upper interval of the Middle Member of the Hueco Limestone were analyzed in regards to depositional environment, facies and sequence stratigraphy. This can elucidate where potential unconventional reservoirs can be found in the Wolfcamp Shale of the Permian Basin. Based on these analyses, 12 lithofacies were identified, including 9 carbonate lithofacies: 1) fenestral dolomudstone, 2) peloidal dolomudstone, 3) ostracode foraminifera packstone, 4) foraminifera peloidal grainstone, 5) skeletal intraclast grainstone, 6) phylloid algal peloidal grainstone, 7) echinoderm phylloid algal packstone, 8) echinoderm bivalve brachiopod …


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 …


Geology, Geochemistry, And 3d Geological Modelling Of The Independencia - Los Bancos Ag-Au Epithermal Vein Systems In The Palmarejo District, Chihuahua, Mexico, Arturo Ramirez 2016 University of Texas at El Paso

Geology, Geochemistry, And 3d Geological Modelling Of The Independencia - Los Bancos Ag-Au Epithermal Vein Systems In The Palmarejo District, Chihuahua, Mexico, Arturo Ramirez

Open Access Theses & Dissertations

The Sierra Madre Occidental (SMO) is a Cretaceous-Tertiary silicic ignimbrite province in northwestern Mexico. It is the result of tectonic and magmatic events produced by the subduction of the Farallon plate under North America (80-40 Ma) and the opening of the Gulf of California (14-12 Ma), thus forming the SMO metallogenic provinces. The Late Eocene to Oligocene was a major period of metallic mineralization hosting various deposit types, principally Ag-Au (±Pb-Zn-Cu) epithermal veins, which have been economically significant.

The study area lies in the Palmarejo district, operated by Coeur Mining Inc., which was the worldâ??s fifth largest silver producer in …


Statistical Analysis Of Arsenic Concentrations In Subsurface Soils At The University Of Mississippi Field Station, David Thomas Webb 2016 University of Mississippi. Sally McDonnell Barksdale Honors College

Statistical Analysis Of Arsenic Concentrations In Subsurface Soils At The University Of Mississippi Field Station, David Thomas Webb

Honors Theses

The purpose of this investigation is to determine how arsenic concentration varies in soils with respect to soil structures, grain size, soil type, and depth. The investigation was conducted at the University of Mississippi Field Station (UMFS). The UMFS is located in Abbeville, MS and is roughly 700 acres in size. It includes ponds and former agricultural fields, and lies within an internally draining basin. Seven boreholes were drilled using a direct push geoprobe and sampled. The cores obtained from the borings were then cut at one foot intervals, producing a total of 90 soil samples. Each sample was observed …


Dating Deformation In The Palmer Zone Of Transpression, Central Massachusetts: Temporal Constraints On Models For Progressive Deformation In The Middle Crust, James K. McCulla 2016 University of Kentucky

Dating Deformation In The Palmer Zone Of Transpression, Central Massachusetts: Temporal Constraints On Models For Progressive Deformation In The Middle Crust, James K. Mcculla

Theses and Dissertations--Earth and Environmental Sciences

The Palmer Zone of Transpression (PZoT) in the Bronson Hill zone of central Massachusetts is an expression of late Paleozoic oblique convergence between Avalonia and Laurentia. The steeply W-dipping, N-S trending PZoT is defined by bounding high strain zones (Mt. Dumplin on west, Central Maine and Conant Brook on east) of opposing shear sense enclosing the Monson orthogneiss. Research was designed to establish the timing of deformation to test the hypothesis that strain in transpressional systems occurs contemporaneously. An understanding of the timing of deformation in this zone could elucidate the mechanisms that formed the zone and contribute to a …


Lithostratigraphic And Geochemical Characterization Of The Upper Pennsylvanian ‘Wolfcamp D’ Shale, Midland Basin (Usa): Implications For Paleoenvironments And Unconventional Petroleum Reserviors, Patrick W. Baldwin 2016 University of Kentucky

Lithostratigraphic And Geochemical Characterization Of The Upper Pennsylvanian ‘Wolfcamp D’ Shale, Midland Basin (Usa): Implications For Paleoenvironments And Unconventional Petroleum Reserviors, Patrick W. Baldwin

Theses and Dissertations--Earth and Environmental Sciences

An integrated stratigraphic analysis of a ~350 ft drill core from Upton County (Texas) has revealed pervasive variability of several key siliciclastic and carbonate lithofacies in vertical section, where organic-rich siliceous mudrock beds alternate with aluminum-rich mudrocks and calcareous gravity flow deposits. Sediment chemistry, especially major and trace elements derived from x-ray fluorescence, captures this variability with high sensitivity. The high frequency chemostratigraphic variability appears to be cyclic, and it is interpreted to represent the first example of deep-water Late Pennsylvanian cyclothems for the Midland Basin. Positive trace metal (Mo, Cr) correlations to total organic carbon and gamma ray response …


Integrated Geophysical Methods In Investigation Of Claiborne Aquifer Hydrostratigraphy, Jackson Purchase, Kentucky, Marie Cooper 2016 University of Kentucky

Integrated Geophysical Methods In Investigation Of Claiborne Aquifer Hydrostratigraphy, Jackson Purchase, Kentucky, Marie Cooper

Theses and Dissertations--Earth and Environmental Sciences

Increased groundwater withdrawals associated with agricultural irrigation in the Jackson Purchase have prompted questions related to groundwater availability and sustainability. Key factors in addressing these questions are understanding the extent and variation in thickness of the local hydrostratigraphic system, which is the upper part of the Mississippi Embayment aquifer system. Correlations of 70 gamma-ray well logs, and 49 resistivity logs were made across parts of the Jackson Purchase in Fulton and Hickman Counties in order to delineate the upper Claiborne aquifer and middle Claiborne confining unit. Commercial software (i.e. Petra 3.8.3) was used to generate cross sections, structure and isopach …


Mobility Of Escherichia Coli Within Karst Terrains, Kentucky, Usa, Ashley M. Bandy 2016 University of Kentucky

Mobility Of Escherichia Coli Within Karst Terrains, Kentucky, Usa, Ashley M. Bandy

Theses and Dissertations--Earth and Environmental Sciences

Bacterial contamination of karst aquifers is a concern as water quality across the globe deteriorates in the face of decreasing water security. This study examined the transport and attenuation of two non-virulent isolates of Escherichia coli in relation to traditional groundwater tracers such as rhodamine WT dye and latex microspheres in two karst regions in Kentucky. Differential movement between the four tracers was observed in both epikarst and karst aquifer traces, with differences in behavior dependent on flow conditions. Attenuation was greater for the bacterial isolate containing the iha gene, compared to the isolate containing the kps gene. Microspheres of …


Spring Responses To Storms And Seasonal Variations In Recharge In The Middle Atlas Region Of Morocco, Brett Andrew Howell 2016 University of Kentucky

Spring Responses To Storms And Seasonal Variations In Recharge In The Middle Atlas Region Of Morocco, Brett Andrew Howell

Theses and Dissertations--Earth and Environmental Sciences

Springs in the Middle Atlas Mountains of Morocco are significant sources for public water supply. From March 2014 to May 2015, water temperatures were measured hourly at three springs (Ribaa, Sidi Rached, and Zerouka); water levels were measured hourly at Sidi Rached and Zerouka; and daily turbidity data were obtained from Ribaa. From March 2014 to March 2015, daily water samples were taken at Zerouka for analyses of the stable isotopes deuterium and oxygen-18. Hourly weather data (precipitation and air temperature) were available from March 2014 to May 2015 from Ifrane, near Zerouka. Temperature responses varied between the springs, showing …


Paleoearthquakes Of The Past ~6000 Years At The Dead Mouse Site, West-Central Denali Fault At The Nenana River, Alaska, Joseph K. Carlson 2016 University of Kentucky

Paleoearthquakes Of The Past ~6000 Years At The Dead Mouse Site, West-Central Denali Fault At The Nenana River, Alaska, Joseph K. Carlson

Theses and Dissertations--Earth and Environmental Sciences

The Denali fault (DF) in south-central Alaska is a major right lateral strike-slip fault that parallels the Alaska Range for much of its length. This fault represents the largest seismogenic source for interior Alaska but due to its remote location and difficulty of access, a dearth of paleoearthquake (PEQ) information exists for this important feature. The fault system is over 1200 km in length and identification of paleoseismic sites that preserve more that 2-3 PEQs has proven challenging. In 2012 and 2015, we developed the ‘Dead Mouse’ site, which provides the first long PEQ record west of the 2002 rupture …


Denali In A Box: Analog Experiments Modeled After A Natural Setting Provide Insight On Gentle Restraining Bend Deformation, Anne M. Fendick 2016 University of Kentucky

Denali In A Box: Analog Experiments Modeled After A Natural Setting Provide Insight On Gentle Restraining Bend Deformation, Anne M. Fendick

Theses and Dissertations--Earth and Environmental Sciences

The Mount McKinley restraining bend (MMRB) creates an ~18° left-step in the arcuate surface trace of the dextral Denali Fault in south-central Alaska. Despite being a large, crustal-scale fault, little is understood about the controls on deformation within the MMRB. Similarities between previous wet kaolin analog modeling and the MMRB suggest that the first-order deformation patterns may derive from similar mechanisms. We compare uplift patterns, localization of deformation, formation of new faults, and displacement fields from the analog model and the natural setting to assess the influence of different variables on the overall system. Despite strong rheological heterogeneity in the …


Stratigraphic, Geochemical, And Well Log Analysis Of The Wolfcamp-D Unconventional Play In The Central Midland Basin, Texas, Patrick Thomas Ryan 2016 University of Kentucky

Stratigraphic, Geochemical, And Well Log Analysis Of The Wolfcamp-D Unconventional Play In The Central Midland Basin, Texas, Patrick Thomas Ryan

Theses and Dissertations--Earth and Environmental Sciences

This M.S. thesis utilizes diverse subsurface datasets from the central Midland Basin, a recently reinvigorated petroleum producing region, to better understand the depositional history of the prospective Wolfcamp-D interval. An integrated set of methods were applied to ~320 ft of drill core from Midland County (Texas). Elemental chemostratigraphy collected via x-ray fluorescence highlights the pervasive fine-scale variability in the stratigraphy of the core, and aided in the classification of three different mudrock facies types. Organic-rich, siliceous mudrocks are cyclically interbedded with aluminum-rich mudrocks and carbonates throughout the Wolfcamp-D. Trace metal correlations with total organic carbon indicate slow bottom-water recharge from …


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