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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 2010 U.S. Geological Survey, Box 25046, M.S. 973, Denver, CO 80225-0046, USA

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

USGS Staff -- Published Research

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 Ties That Bind: Soil Surveyor William Edgar Tharp And Oceanographic Cartographer Marie Tharp, Edward R. Landa 2010 U.S. Geological Survey

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

USGS Staff -- Published Research

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 ...


Uranium-Series Dating Of Gypsum Speleothems: Methodology And Examples, Laura Sanna, Francisco Saez, Siri Simonsen, Silviu Constantin, José-Maria Calaforra, Paolo Forti, Stein-Erik Lauritzen 2010 Bergen University

Uranium-Series Dating Of Gypsum Speleothems: Methodology And Examples, Laura Sanna, Francisco Saez, Siri Simonsen, Silviu Constantin, José-Maria Calaforra, Paolo Forti, Stein-Erik Lauritzen

International Journal of Speleology

The analytical problems of dating gypsum speleothems with the U-series technique are reviewed. Gypsum speleothems are, in general, very low in U content, challenging the limits of detection methods. Various approaches to dissolving gypsum and isolation of actinides from the matrix include ion-pairing dissolution with magnesium salts and using nitric acid. The most precise dating technique is Thermal Ionization Mass Spectrometry (TIMS), combined with Fe(OH)3 scavenging and anionic exchange chromatography. Less satisfactory, but much quicker, is direct retention of actinides from HNO3 by means of TRU resin and MC-ICP-MS detection. We have tested these methods on gypsum ...


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 2010 University of Nebraska-Lincoln

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

Papers in the Earth and Atmospheric Sciences

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 ...


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 2010 University of Texas at Austin

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

Papers in the Earth and Atmospheric Sciences

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 ...


Salinity Dynamics Of Discharge Lakes In Dune Environments: Conceptual Model, Vitaly A. Zlotnik, Neville I. Robinson, Craig T. Simmons 2010 University of Nebraska-Lincoln

Salinity Dynamics Of Discharge Lakes In Dune Environments: Conceptual Model, Vitaly A. Zlotnik, Neville I. Robinson, Craig T. Simmons

Papers in the Earth and Atmospheric Sciences

Lakes of varying salinity are ubiquitous in dune environments with semiarid climates. Often these lakes become solute traps due to specific groundwater flow conditions. Over geological time after emergence of such lakes, the groundwater flow and mass transport processes lead to accumulation of solutes. This salinity increase can result in mineral deposition and free convection from lakes. However, high solute concentrations in these lakes are often not observed. We propose a conceptual model that estimates the lake salinity dynamics and yields concentration profiles beneath the lakes over centennial and millennial scales. Unlike previous approaches, a simple mathematical model is proposed ...


Effects Of Irrigated Agroecosystems: 1. Quantity Of Soil Water And Groundwater In The Southern High Plains, Texas, B. R. Scanlon, R. C. Reedy, J. B. Gates 2010 University of Texas at Austin

Effects Of Irrigated Agroecosystems: 1. Quantity Of Soil Water And Groundwater In The Southern High Plains, Texas, B. R. Scanlon, R. C. Reedy, J. B. Gates

Papers in the Earth and Atmospheric Sciences

Although irrigated agriculture is the primary consumer of global groundwater resources, information on recharge rates and sustainable irrigation is limited. The study objective was to fingerprint irrigation return flow to quantify percolation/recharge and to estimate sustainable irrigation levels. This paper focuses on water quantity; a companion paper addresses water quality. Soil samples from 13 boreholes drilled beneath irrigated agroecosystems in the southern High Plains were analyzed for matric potential and waterextractable Cl and NO3. Unsaturated zone pore water beneath irrigated agroecosystems can be fingerprinted by higher matric potentials (wetter soils, median mp: −40 m) and higher NO3 ...


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 2010 Harvard University

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

Papers in the Earth and Atmospheric Sciences

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 (PM2.5) 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 ...


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 2010 Colorado State University - Fort Collins

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

USGS Staff -- Published Research

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 and 10 ...


The Cleaning Of Burned And Contaminated Archaeological Maize Prior To 87sr/86sr Analysis, L.V. Benson, H. E. Taylor, T. I. Plowman, D. A. Roth, R. C. Antweiler 2010 U.S. Geological Survey

The Cleaning Of Burned And Contaminated Archaeological Maize Prior To 87sr/86sr Analysis, L.V. Benson, H. E. Taylor, T. I. Plowman, D. A. Roth, R. C. Antweiler

USGS Staff -- Published Research

Accurate trace-metal and strontium-isotope analyses of archaeological corn cobs require that metal contaminants be removed prior to chemical analysis. Archaeological cobs are often coated with construction debris, dust, or soilwhich contains mineral particles. In addition, most archaeological cobs are partially or completely burned and the burned parts incorporate mineral debris in their hardened residual structures. Unburned cobs are weak ion exchangers and most metals within a cob are not firmly bound to cob organic matter; therefore, immersing cobs in acids and rinsing them in deionized water to remove mineral contaminants may result in the undesirable loss of metals, including strontium ...


Tree-Ring Dates And Demographic Change In The Southern Colorado Plateau And Rio Grande Regions, Michael S. Berry, Larry Benson 2010 Bureau of Reclamation, Salt Lake City, UT

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

USGS Staff -- Published Research

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 ...


Development And Application Of A Pollen-Based Paleohydrologic Reconstruction From The Lower Roanoke River Basin, North Carolina, Usa, Debra Willard, Christopher Bernhardt, Roger Brown, Bryan Landacre, Philip A. Townsend 2010 US Geological Survey

Development And Application Of A Pollen-Based Paleohydrologic Reconstruction From The Lower Roanoke River Basin, North Carolina, Usa, Debra Willard, Christopher Bernhardt, Roger Brown, Bryan Landacre, Philip A. Townsend

USGS Staff -- Published Research

We used pollen assemblages to reconstruct late-Holocene paleohydrologic patterns in floodplain deposits from the lower Roanoke River basin (North Carolina, southeastern USA). Using 120 surface samples from 38 transects, we documented statistical relationships between pollen assemblages, vegetation, and landforms. Backswamp pollen assemblages (long hydroperiods) are dominated by Nyssa (tupelo) and Taxodium (cypress) and have high pollen concentrations. Sediments from elevated levees and seasonally flooded forests (shorter hydroperiods) are characterized by dominant Pinus (pine) pollen, variable abundance of hardwood taxa, and low pollen concentrations. We apply the calibration data set to interpret past vegetation and paleohydrology. Pollen from a radiocarbon-dated sediment ...


Absorption And Biotransformation Of Polybrominated Diphenyl Ethers De-71 And De-79 In Chicken (Gallus Gallus), Mallard (Anas Platyrhynchos), American Kestrel (Falco Sparverius) And Black-Crowned Night-Heron (Nycticorax Nycticorax) Eggs, Moira A. McKernan, Barnett A. Rattner, Jeff S. Hatfield, Robert C. Hale, Mary Ann Ottinger 2010 University of Maryland

Absorption And Biotransformation Of Polybrominated Diphenyl Ethers De-71 And De-79 In Chicken (Gallus Gallus), Mallard (Anas Platyrhynchos), American Kestrel (Falco Sparverius) And Black-Crowned Night-Heron (Nycticorax Nycticorax) Eggs, Moira A. Mckernan, Barnett A. Rattner, Jeff S. Hatfield, Robert C. Hale, Mary Ann Ottinger

USGS Staff -- Published Research

We recently reported that air cell administration of penta-brominated diphenyl ether (penta-BDE; DE-71) evokes biochemical and immunologic effects in chicken (Gallus gallus) embryos at very low doses, and impairs pipping (i.e., stage immediately prior to hatching) and hatching success at 1.8 µg g-1 egg (actual dose absorbed) in American kestrels (Falco sparverius). In the present study, absorption of polybrominated diphenyl ether (PBDE) congeners was measured following air cell administration of a penta-BDE mixture (11.1 lg DE-71 g-1 egg) or an octa-brominated diphenyl ether mixture (octa BDE; DE-79; 15.4 lg DE-79 g-1 egg). Uptake ...


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 2010 University of Wisconsin - Madison

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

USGS Staff -- Published Research

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 ...


Abandoned Mine Drainage In The Swatara Creek Basin, Southern Anthracite Coalfield, Pennsylvania, Usa: 2. Performance Of Treatment Systems, Charles A. Cravotta III 2010 US Geological Survey, PA Water Science Center, 215 Limekiln Rd, New Cumberland, PA, USA

Abandoned Mine Drainage In The Swatara Creek Basin, Southern Anthracite Coalfield, Pennsylvania, Usa: 2. Performance Of Treatment Systems, Charles A. Cravotta Iii

USGS Staff -- Published Research

A variety of passive and semi-passive treatment systems were constructed by state and local agencies to neutralize acidic mine drainage (AMD) and reduce the transport of dissolved metals in the upper Swatara Creek Basin in the Southern Anthracite Coalfield in eastern Pennsylvania. To evaluate the effectiveness of selected treatment systems installed during 1995–2001, the US Geological Survey collected water-quality data at upstream and downstream locations relative to each system eight or more times annually for a minimum of 3 years at each site during 1996– 2007. Performance was normalized among treatment types by dividing the acid load removed by ...


Recent Advances In Global Lake Coring Hold Promise For Global Change Research In Paleolimnology, Walter E. Dean 2010 U.S. Geological Survey, Denver, CO

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

USGS Staff -- Published Research

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.


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 2010 Denver Federal Center

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

USGS Staff -- Published Research

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 ...


The Influence Of Topology On Hydraulic Conductivity In A Sand-And-Gravel Aquifer, Roger H. Morin, Denis R. LeBlanc, Brent M. Troutman 2010 Denver Federal Center

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

USGS Staff -- Published Research

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 ...


Holocene Landscape Response To Seasonality Of Storms In The Mojave Desert, David M. Miller, Kevin M. Schmidt, Shannon A. Mahan, John P. McGeehin, Lewis A. Owen, John A. Barron, Frank Lehmkuhl, Rene Lohrer 2010 U.S. Geological Survey, 345 Middlefield Road, MS-973, Menlo Park, CA 94025, USA

Holocene Landscape Response To Seasonality Of Storms In The Mojave Desert, David M. Miller, Kevin M. Schmidt, Shannon A. Mahan, John P. Mcgeehin, Lewis A. Owen, John A. Barron, Frank Lehmkuhl, Rene Lohrer

USGS Staff -- Published Research

New optically stimulated and radiocarbon ages for alluvial fan and lake deposits in the Mojave Desert are presented, which greatly improves the temporal resolution of surface processes. The new Mojave Desert climate-landscape record is particularly detailed for the late Holocene. Evidence from ephemeral lake deposits and landforms indicates times of sustained stream flow during a wet interval of the latter part of the Medieval Warm Period at ca. AD 1290 and during the Little Ice Age at ca. AD 1650. The former lakes postdate megadroughts of the Medieval Warm Period, whereas the latter match the Maunder Minimum of the Little ...


In-Situ Stress And Fracture Characterization For Planning Of An Egs Stimulation In The Desert Peak Geothermal Field, Nevada, Stephen H. Hickman, Nicholas C. Davatzes 2010 U.S. Geological Survey

In-Situ Stress And Fracture Characterization For Planning Of An Egs Stimulation In The Desert Peak Geothermal Field, Nevada, Stephen H. Hickman, Nicholas C. Davatzes

USGS Staff -- Published Research

An integrated study of natural fracture geometry, fluid flow and stress was conducted in Desert Peak well 27-15 in preparation for development of an Enhanced Geothermal System (EGS) through hydraulic stimulation. This stimulation will be carried out at depths of ~3000 to 3500 ft in units comprised of silicified rhyolite tuffs and metamorphosed mudstones at ambient temperatures of ~180 to 195° C. Our previous analyses of borehole image logs from this well showed that the current minimum horizontal principal stress, Shmin, is oriented 114 ± 17º and that numerous fractures in the planned stimulation interval are optimally oriented for normal faulting ...


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