Digital Commons Network^™

Enigmatic Structures On Upper Pleistocene Laminar Caliche Surfaces Of The Bahamas: Animal, Vegetable, Or Mineral?, H. Allen Curran

Geosciences: Faculty Publications

Trace fossils are a common and important component of most Quaternary carbonate rock units of the Bahamas and other, similar tropical carbonate regions. In the Bahamas, the Pleistocene-Holocene boundary is typically marked by a calichified paleosol horizon that formed on the exposed limestone surfaces of the islands during the time of lowered sea level of the Last Glacial. On the north coast of San Salvador Island, an extensive horizontal surface of laminar caliche is exposed at Singer Bar Point and to the west. This surface formed on carbonate eolianite of Late Pleistocene (Eemian) age and is overlain by Holocene eolianite. …

A Real Time Optical Biosensor Assay For Amoxicillin And Other Β-Lactams In Water Samples, Israel M. Scott, Lewis J. Kraft, Jonathan D. Parker, Kathryn Daniel, Sarah Kustick, Diana Kennen, Jonathan L. Mcmurry

Faculty Articles

Antibiotic contamination of drinking water and sewage is a matter of environmental and public health concern. Traditionally, ELISA or HPLC methods have been used to detect and measure antibiotic contamination. By applying an optical biosensing method, biolayer inteferometry (BLI), we have developed a kinetic competition binding assay capable of quantitating less than lppm (~33 μM) amoxicillin. Similar to surface plasmon resonance, BLI senses changes that occur upon binding of one molecule to another near a surface to measure association and dissociation. Immobilized amoxicillin was used to screen for binding against an analyte solution of anti-amoxicillin equilibrated with amoxicillin-containing water samples, …

Enhanced Late Holocene Enso/Pdo Expression Along The Margins Of The Eastern North Pacific, John A. Barron, Lesleigh Anderson

United States Geological Survey: Staff Publications

Pacific climate is known to have varied during the Holocene, but spatial patterns remain poorly defined. This paper compiles terrestrial and marine proxy data from sites along the northeastern Pacific margins and proposes that they indicate 1) suppressed ENSO conditions during the middle Holocene between ~8000 and 4000 cal BP with a North Pacific that generally resembled a La Niña-like or more negative PDO phase and 2) a climate transition between ~4200 and 3000 cal BP that appears to be the teleconnected expression to a more modern-like ENSO Pacific. Compared to modern day conditions, the compiled data suggest that during …

Recent Advances In Global Lake Coring Hold Promise For Global Change Research In Paleolimnology, Walter E. Dean

United States Geological Survey: Staff Publications

Thank you, Antje, for your generous comments and I thank IPA for presenting me with this award along with three giants of paleolimnology! I am humbled and delighted to accept this award as a representative of all those in the Paleolimnology community whose creative insights continue to make Paleolimnology inspiring.

Evidence For Recent Population Bottlenecks In Northern Spotted Owls (Strix Occidentalis Caurina), W. Chris Funk, Eric D. Forsman, Matthew Johnson, Thomas D. Mullins, Susan M. Haig

United States Geological Survey: Staff Publications

The northern spotted owl (Strix occidentalis caurina) is one of the most controversial threatened subspecies ever listed under the US Endangered Species Act. Despite protection of its remaining forest habitat, recent field studies show continued declines of northern spotted owls. One potential threat to northern spotted owls which has not yet been shown is loss of genetic variation from population bottlenecks. Bottlenecks can increase the probability of mating among related individuals, potentially causing inbreeding depression, and can decrease adaptive potential. Here we report evidence for recent bottlenecks in northern spotted owls using a large genetic dataset (352 individuals …

Tree-Ring Dates And Demographic Change In The Southern Colorado Plateau And Rio Grande Regions, Michael S. Berry, Larry Benson

United States Geological Survey: Staff Publications

In this chapter, tree-ring dates from the southern Colorado Plateau, Mogollon Highlands, and Rio Grande areas (fig. 3-1) (hereafter referred to as the study area) are used to estimate regional-scale timber-harvesting and construction activities between AD 600 and 1600 (the Basketmaker III through Pueblo IV periods). Within that time span, we focus our attention particularly on the AD 1045-1300 period, a time when anomalously wet periods alternated with megadroughts (fig. 3.2). Treering- date distributions (histograms) for eight archaeological subregions within the study area have been created using a database of more than twenty-four thousand tree-ring dates from archaeological sites. These …

Barcoding Bushmeat: Molecular Identification Of Central African And South American Harvested Vertebrates, Mitchell J. Eaton, Greta L. Meyers, Sergios-Orestis Kolokotronis, Matthew S. Leslie, Andrew P. Martin, George Amato

United States Geological Survey: Staff Publications

The creation and use of a globally available database of DNA sequences from a standardized gene region has been proposed as a tool for species identification, assessing genetic diversity and monitoring the legal and illegal trade in wildlife species. Here, we contribute to the Barcode of Life Data System and test whether a short region of the mitochondrial cytochrome c oxidase subunit 1 (COX1) gene would reliably distinguish among a suite of commonly hunted African and South American mammal and reptile species. We used universal primers to generate reference barcode sequences of 645 bp for 23 species from five vertebrate …

Mineralogical And Chemical Characteristics Of Some Natural Jarosites, George A. Desborough, Kathleen S. Smith, Heather A. Lowers, Gregg A. Swayze, Jane M. Hammarstrom, Sharon F. Diehl, Reinhard W. Leinz, Rhonda L. Driscoll

United States Geological Survey: Staff Publications

This paper presents a detailed study of the mineralogical, microscopic, thermal, and spectral characteristics of jarosite and natrojarosite minerals. Systematic mineralogic and chemical examination of a suite of 32 natural stoichiometric jarosite and natrojarosite samples from diverse supergene and hydrothermal environments indicates that there is only limited solid solution between Na and K at low temperatures, which suggests the presence of a solvus in the jarosite-natrojarosite system at temperatures below about 140 °C. The samples examined in this study consist of either end members or coexisting end-member pairs of jarosite and natrojarosite. Quantitative electron-probe microanalysis data for several natural hydrothermal …

The Influence Of Topology On Hydraulic Conductivity In A Sand-And-Gravel Aquifer, Roger H. Morin, Denis R. Leblanc, Brent M. Troutman

United States Geological Survey: Staff Publications

A field experiment consisting of geophysical logging and tracer testing was conducted in a single well that penetrated a sand-and-gravel aquifer at the U.S. Geological Survey Toxic Substances Hydrology research site on Cape Cod, Massachusetts. Geophysical logs and flowmeter/pumping measurements were obtained to estimate vertical profiles of porosity ϕ, hydraulic conductivity K, temperature, and bulk electrical conductivity under background, freshwater conditions. Saline-tracer fluid was then injected into the well for 2 h and its radial migration into the surrounding deposits was monitored by recording an electromagnetic-induction log every 10 min. The field data are analyzed and interpreted primarily …

Heat Flow And Hydrologic Characteristics At The And-1b Borehole, Andrill Mcmurdo Ice Shelf Project, Antarctica, Roger H. Morin, Trevor Williams, Stuart A. Henrys, Diana Magens, Frank Niessen, Dhiresh Hansaraj

United States Geological Survey: Staff Publications

The Antarctic Drilling Program (ANDRILL) successfully drilled and cored a borehole, AND-1B, beneath the McMurdo Ice Shelf and into a flexural moat basin that surrounds Ross Island. Total drilling depth reached 1285 m below sea floor (mbsf) with 98 percent core recovery for the detailed study of glacier dynamics. With the goal of obtaining complementary information regarding heat fl ow and permeability, which is vital to understanding the nature of marine hydrogeologic systems, a succession of three temperature logs was recorded over a five day span to monitor the gradual thermal recovery toward equilibrium conditions. These data were extrapolated to …

Scale‐Invariant Stress Orientations And Seismicity Rates Near The San Andreas Fault, Amy Day-Lewis, Mark D. Zoback, Stephen Hickman

United States Geological Survey: Staff Publications

We analyzed measurements of the direction of maximum horizontal compressive stress as a function of depth in two scientific research wells near the San Andreas Fault in central and southern California. We found that the stress orientations exhibit scale‐invariant fluctuations over intervals from tens of cm to several km. Similarity between the scaling of the stress orientation fluctuations and the scaling of earthquake frequency with fault size suggests that these fluctuations are controlled by stress perturbations caused by slip on faults of various sizes in the critically‐stressed crust adjacent to the fault. The apparent difference in stress scaling parameters between …

The Ties That Bind: Soil Surveyor William Edgar Tharp And Oceanographic Cartographer Marie Tharp, Edward R. Landa

United States Geological Survey: Staff Publications

The link between soil science and geology is personified in the American father and daughter: soil surveyor William Edgar Tharp (1870–1959) and oceanographic cartographer Marie Tharp (1920–2006). From 1904 to 1935, W.E. Tharp mapped soils in 14 states for the US Department of Agriculture, and campaigned during the late 1920s–early 1930s to raise awareness of the high rates of soil erosion from croplands. The lifestyle of the federal soil surveyor in the United States during the early 20th century involved frequent household moves, and it played a formative role in Marie Tharp’s childhood. Her path to a career in geology …

Microbial Production Of Isotopically Light Iron(Ii) In A Modern Chemically Precipitated Sediment And Implications For Isotopic Variations In Ancient Rocks, G. E. Tangalos, B. L. Beard, C. M. Johnson, Charles N. Alpers, E. S. Shelobolina, H. Xu, H. Konishi, E. E. Roden

United States Geological Survey: Staff Publications

The inventories and Fe isotope composition of aqueous Fe(II) and solid-phase Fe compounds were quantified in neutral-pH, chemically precipitated sediments downstream of the Iron Mountain acid mine drainage site in northern California, USA. The sediments contain high concentrations of amorphous Fe(III) oxyhydroxides [Fe(III)_am] that allow dissimilatory iron reduction (DIR) to predominate over Fe–S interactions in Fe redox transformation, as indicated by the very low abundance of Cr(II)-extractable reduced inorganic sulfur compared with dilute HCl-extractable Fe. δ⁵⁶Fe values for bulk HCl- and HF-extractable Fe were ≈ 0. These near-zero bulk δ⁵⁶Fe values, together with the …

To The Ice: George Bird Grinnell's 1887 Ascent Of Grinnell Glacier, Richard Vaughan

Articles by Maurer Faculty

This article discusses a climbing expedition undertaken by U.S. conservationist George Bird Grinnell to ascend what would come to be known as Grinnell Glacier in Montana. Grinnell’s efforts to establish Glacier National Park are detailed. Grinnell’s previously unpublished descriptions of the glacier and its surrounding area are analyzed by the author.

Synthesis Of Satellite (Modis), Aircraft (Icartt), And Surface (Improve, Epa‐Aqs, Aeronet) Aerosol Observations Over Eastern North America To Improve Modis Aerosol Retrievals And Constrain Surface Aerosol Concentrations And Sources, Easan Drury, Daniel J. Jacob, Robert J. D. Spurr, Jun Wang, Yohei Shinozuka, Bruce E. Anderson, Antony D. Clarke, Jack Dibb, Cameron Mcnaughton, Rodney Weber

Department of Earth and Atmospheric Sciences: Faculty Publications

We use an ensemble of satellite (MODIS), aircraft, and ground‐based aerosol observations during the ICARTT field campaign over eastern North America in summer 2004 to (1) examine the consistency between different aerosol measurements, (2) evaluate a new retrieval of aerosol optical depths (AODs) and inferred surface aerosol concentrations (PM_2.5) from the MODIS satellite instrument, and (3) apply this collective information to improve our understanding of aerosol sources. The GEOS‐Chem global chemical transport model (CTM) provides a transfer platform between the different data sets, allowing us to evaluate the consistency between different aerosol parameters observed at different times and …

Nebraska Statewide Groundwater-Level Monitoring Report 2010, J. T. Korus, M. E. Burbach, L. M. Howard, R. M. Joeckel

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Holdrege: Nebraska's State Soil

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Melting Alpine Glaciers Enrich High-Elevation Lakes With Reactive Nitrogen, Jasmine E. Saros, Kevin C. Rose, David W. Clow, Verlin C. Stevens, Andrea B. Nurse, Heather A. Arnett, Jeffery R. Stone, Craig E. Williamson, Alexander P. Wolfe

Department of Earth and Atmospheric Sciences: Faculty Publications

Alpine glaciers have receded substantially over the last century in many regions of the world. Resulting changes in glacial runoff not only affect the hydrological cycle, but can also alter the physical (i.e., turbidity from glacial flour) and biogeochemical properties of downstream ecosystems. Here we compare nutrient concentrations, transparency gradients, algal biomass, and fossil diatom species richness in two sets of high-elevation lakes: those fed by snowpack melt alone (SF lakes) and those fed by both glacial and snowpack meltwaters (GSF lakes). We found that nitrate (NO₃^-) concentrations in the GSF lakes were 1-2 orders of magnitude …

Centennial Eolian Cyclicity In The Great Plains, Usa: A Dominant Climate Pattern Of Wind Transport Over The Past 4000 Years?, Antje Schwalb, Walter E. Dean, Sherilyn C. Fritz, Christoph E. Geiss, Bernd Kromer

Department of Earth and Atmospheric Sciences: Faculty Publications

Proxy evidence at decadal resolution from Late Holocene sediments from Pickerel Lake, northeastern South Dakota, shows distinct centennial cycles (400-700 years) in magnetic susceptibility; contents of carbonate, organic carbon, and major elements; abundance in ostracodes; and δ¹⁸O and δ¹³C values in calcite. Proxies indicate cyclic changes in eolian input, productivity, and temperature. Maxima in magnetic susceptibility are accompanied by maxima in aluminum and iron mass accumulation rates (MARs), and in abundances of the ostracode Fabaeformiscandona rawsoni. This indicates variable windy, and dry conditions with westerly wind dominance, including during the Medieval Climate Anomaly. Maxima in …

Millennial-Scale Climate Variability During The Last Glacial Period In The Tropical Andes, Sherilyn C. Fritz, P. A. Baker, E. Ekdahl, G. O. Seltzer, L. R. Stevens

Department of Earth and Atmospheric Sciences: Faculty Publications

Millennial-scale climate variation during the Last Glacial period is evident in many locations worldwide, but it is unclear if such variation occurred in the interior of tropical South America, and, if so, how the low-latitude variation was related to its high-latitude counterpart. A high-resolution record, derived from the deep drilling of sediments on the floor of Lake Titicaca in the southern tropical Andes, is presented that shows clear evidence of millennial-scale climate variation between ~60 and 20 ka BP. This variation is manifested by alternations of two interbedded sedimentary units. The two units have distinctive sedimentary, geochemical, and paleobiotic properties …

Groundwater Recharge In Natural Dune Systems And Agricultural Ecosystems In The Thar Desert Region, Rajasthan, India, Bridget Scanlon, Abhijit Mukherjee, John B. Gates, Robert C. Reedy, Amarendra K. Sinha

Department of Earth and Atmospheric Sciences: Faculty Publications

Water and nutrient availability for crop production are critical issues in (semi)arid regions. Unsaturated-zone Cl tracer data and nutrient (NO₃ and PO₄) concentrations were used to quantify recharge rates using the Cl mass balance approach and nutrient availability in the Thar Desert, Rajasthan, India. Soil cores were collected in dune/interdune settings in the arid Thar Desert (near Jaisalmer) and in rain-fed (nonirrigated) and irrigated cropland in the semiarid desert margin (near Jaipur). Recharge rates were also simulated using unsaturated zone modeling. Recharge rates in sparsely vegetated dune/interdune settings in the Jaisalmer study area are 2.7-5.6 mm/year (2-3% …

Stratigraphic Signature Of The Late Palaeozoic Ice Age In The Parmeener Supergroup Of Tasmania, Se Australia, And Inter-Regional Comparisons, Christopher R. Fielding, Tracy D. Frank, John L. Isbell, Lindsey C. Henry, Eugene W. Domack

Department of Earth and Atmospheric Sciences: Faculty Publications

Recent research in eastern Australia has established that rather than being a single, long-lived epoch, the late Palaeozoic Ice Age comprised a series of glacial intervals each 1–8 million years in duration, separated by non-glacial intervals of comparable duration. In order to test whether the glacial events recognized in New South Wales and Queensland have broader extent, we conducted a reappraisal of the Parmeener Supergroup of Tasmania, southeast Australia. A facies analysis of the Pennsylvanian to Permian section was carried out, allowing rationalization of the succession into four recurrent facies associations: a) glacigenic facies association, restricted to the basal Pennsylvanian/earliest …

Tetrapod Fauna Of The Lowermost Usili Formation (Songea Group, Ruhuhu Basin) Of Southern Tanzania, With A New Burnetiid Record, Christian A. Sidor, Kenneth D. Angielczyk, D. Marie Weide, Roger M. H. Smith, Sterling J. Nesbitt, Linda A. Tsuji

Department of Earth and Atmospheric Sciences: Faculty Publications

Vertebrate fossils from the Ruhuhu Basin of southern Tanzania have been known for over 75 years, but the details of their stratigraphic distribution remain imperfectly understood. Recent fieldwork in the Upper Permian Usili Formation (Songea Group) has led to the discovery of a tetrapod assemblage in a conglomeratic unit at its base. The fossils are concentrated in matrix-supported intraformational clay pebble conglomerates interpreted as mass flow deposits in wide, shallow channels in the distal reaches of an alluvial fan. Included in this new collection are fossils representing the first record of a burnetiid therapsid from Tanzania. The anatomy of the …

Improved Algorithm For Modis Satellite Retrievals Of Aerosol Optical Thickness Over Land In Dusty Atmosphere: Implications For Air Quality Monitoring In China, Jun Wang, Xiaoguang Xu, R. Spurr, Yuxuang Wang, Easan Drury

Department of Earth and Atmospheric Sciences: Faculty Publications

A new algorithm, using the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite reflectance and aerosol single scattering properties simulated from a chemistry transport model (GEOS-Chem), is developed to retrieve aerosol optical thickness (AOT) over land in China during the spring dust season. The algorithmfirst uses a “dynamic lower envelope” approach to sample theMODIS dark-pixel reflectance data in lowAOT conditions, to derive the local surface visible (0.65 μm)/near infrared (NIR, 2.1 μm) reflectance ratio. Joint retrievals of AOT at 0.65 μm and surface reflectance at 2.1 μm are then performed, based on the time, location, and spectraldependent single scattering properties of the …

Feasibility Of Using 15N-Enriched Escherichia Coli As A Bacterial Tracer In The Cane Run/Royal Spring Basin, Kentucky, John G. Warden

University of Kentucky Master's Theses

A novel tracer method has used ¹⁵N to label Escherichia coli and track the transport of bacteria, a common contaminant, through karst aquifers. Use of this method could provide valuable insight into the movement of bacteria in aquifers, which would help improve remediation methods and strategies. A wild strain of E. coli was isolated from the Cane Run/Royal Spring basin in the Inner Bluegrass region of Kentucky. The strain was serotyped O^-:H^- and virulence testing showed the strain did not have virulence factors of E. coli commonly pathogenic to humans. Five karst microcosms were filled with …

Chromium, Copper, And Arsenic Concentration And Speciation In Soil Adjacent To Chromated Copper Arsenate (Cca) Treated Lumber Along A Topohydrosequence, Donald Roy Schwer Iii

University of Kentucky Master's Theses

Arsenic (As), Chromium (Cr), and Copper (Cu) are ubiquitous in soils as a result of anthropogenic and geogenic processes. The fate of As, Cr, and Cu in the environment is largely governed by their speciation, which is influenced by soil physiochemical properties. This study investigated the influence of soil physiochemical properties and landscape position on As, Cr, and Cu concentration and speciation in soils adjacent to Chromated Copper Arsenate (CCA) treated lumber fence posts. Concentration gradients showed elevated total As and Cu adjacent to the three fence posts, which decreased with increasing distance from the posts. In addition, As and …

Origin Of Blue Ridge Basement Rocks, Dellwood Quad, Western Nc: New Evidence From U-Pb Zircon Geochronology And Whole Rock Geochemistry, Donald Franklin Loughry Jr.

University of Kentucky Master's Theses

Terrane discrimination in polycyclic continental basement rocks is challenging due to high-grade metamorphism and intense deformation. Based on early USGS mapping the Blue Ridge basement in the Dellwood quadrangle of the eastern Great Smoky Mountains was proposed to consist of augen orthogneisses of Laurentian (Grenvillian) affinity interfolded with migmatitic hornblende and biotite paragneisses (“Carolina Gneiss”) and amphibolites of uncertain affinity. However, detailed study reveals that the hornblende gneiss of Hadley and Goldsmith (1963) is a heterogeneous map unit consisting of (1)metaplutonic rocks; (2) variably foliated and folded felsic orthogneisses; (3) strongly migmatitic, folded Hbl+Bt-bearing gneisses; (4) foliated and lineated garnet …

Tectonic Controls On Lower Devonian Sandstone Distribution, Alabama, Michael P. Solis

University of Kentucky Master's Theses

The Devonian Frog Mountain Formation thickens abruptly eastward across the Eastern Coosa thrust fault from <12 m on the west to>70 m on the east. The thin Frog Mountain on the west unconformably overlies the Cambrian-Ordovician Knox Group. The thin Frog Mountain (mostly shale) is overlain by the Mississippian Maury Shale (~1 m thick) and Fort Payne Chert (~50 m thick). The thick Frog Mountain on the east rests on the Middle Ordovician Athens Shale, a black shale >150 m thick. The Athens overlies the Knox Group. The thick Frog Mountain is nearly all sandstone and is overlain by Fort Payne Chert which is only …

The No. 5 Block In Eastern Kentucky: A Critical Re-Examination Of The Petrology With Special Attention To The Origin Of Inertinite Macerals In The Splint Lithotypes, Allison Ranae Richardson

University of Kentucky Master's Theses

Microbes, including fungi and bacteria, and insects are responsible for the consumption and subsequent degradation of plant materials into humus. These microbes directly and indirectly affect the physical and chemical characteristics of coal macerals. Efforts to understand and determine the origins of inertinite macerals are largely misrepresented in the literature, conforming to a single origin of fire. This study focuses on the variability of physical and inferred chemical differences observed petrographically between the different inertinite macerals and discusses the multiple pathways plant material may take to form and or degrade these macerals.

Petrographic results show that fungal activity plays a …

Latest Quaternary Paleoclimate Reconstruction Utilizing Stable Isotopic And Trace Element Proxies In A Stalagmite From Culverson Creek Cave, West Virginia, Ashley Nicole Gilbert

University of Kentucky Master's Theses

A reconstruction of regional climate variability in southern West Virginia that spans the last glacial/interglacial transition is presented. Paleoclimate interpretations obtained from the 50-cm long stalagmite provide key insights regarding the timing, magnitude, and forcing mechanisms responsible for past climate variability. Stable isotopic (δ¹⁸O and δ¹³C) and trace element (Ba, Sr, Mg) signatures from samples contiguously milled along the growth-axis of a ²³⁰Th-dated stalagmite which grew between approximately 20 and 5 thousand years before present (kyr BP) provide critical constraints for above-cave mean annual temperature, seasonality of moisture mean annual precipitation, and potential vegetation shifts. …