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United States Geological Survey: Staff Publications

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Full-Text Articles in Earth Sciences

Overview Of Hydrocarbon Production, Consumption, Reserves And Potential, At World And Local Scales, Mitchell E. Henry, Debra Higley Jan 2002

Overview Of Hydrocarbon Production, Consumption, Reserves And Potential, At World And Local Scales, Mitchell E. Henry, Debra Higley

United States Geological Survey: Staff Publications

Hydrocarbon (oil and gas) production and consumption, along with remaining resources, are irregularly distributed across the world and within countries. Daily world hydrocarbon production, in 1999, was 72.6 million barrels of oil (mbo) and 232 billion cubic feet of gas (bcfg). Daily average production in 1999, for North America, was 14 mbo and 71.7 bcfg, and, for the United States, it was 8.1 mbo and 50.9 bcfg. North American average daily consumption for 1999 was 23.4 mbo and 71.5 bcfg. The United States produced 42 percent of the oil and 85 percent of the gas it consumed in 1999. Onshore …

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West Nile Virus: A Threat To North American Avian Species, Robert G. Mclean Jan 2002

West Nile Virus: A Threat To North American Avian Species, Robert G. Mclean

United States Geological Survey: Staff Publications

West Nile virus (WNV) was introduced into the United States (US), specifically in New York City (NYC), in 1999; this translocation represented a major shift out of its normal geographical distribution of Africa, the Middle East, Europe and the western parts of Asia (Center for Disease Control 1999a). The route or method of entry into the US is still unknown. WNV is in the genus Flavivirus, the family Flaviviridae and is closely related to some other viruses in this family, such as Japanese encephalitis virus in Southeast Asia, Murray Valley encephalitis virus in Australia and St. Louis encephalitis (SLE) …

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The Last Interglacial Period On The Pacific Coast Of North America: Timing And Paleoclimate, Daniel R. Muhs, Kathleen R. Simmons, George L. Kennedy, Thomas K. Rockwell Jan 2002

The Last Interglacial Period On The Pacific Coast Of North America: Timing And Paleoclimate, Daniel R. Muhs, Kathleen R. Simmons, George L. Kennedy, Thomas K. Rockwell

United States Geological Survey: Staff Publications

New, high-precision U-series ages of solitary corals (Balanophyllia elegans) coupled with molluscan faunal data from marine terraces on the Pacific Coast of North America yield information about the timing and warmth of the last interglacial sea-level highstand. Balanophyllia elegans takes up U in isotopic equilibrium with seawater during growth and shortly after death. Corals from the second terrace on San Clemente Island (offshore southern California), the third terrace on Punta Banda (on the Pacific Coast of northern Baja California), and the Discovery Point Formation on Isla de Guadalupe (in the Pacific Ocean offshore Baja California) date to the …

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Last Interglacial Climates, George J. Kukla, Michael L. Bender, Jacques-Louis De Beaulieu, Gerard Bond, Wallace S. Broecker, Piet Cleveringa, Joyce E. Gavin, Timothy D. Herbert, John Imbrie, Jean Jouzel, Lloyd D. Keigwin, Karen-Luise Knudsen, Jerry F. Mcmanus, Josef Merkt, Daniel R. Muhs, Helmut Muller, Richard Z. Poore, Stephen C. Porter, Guy Seret, Nicholas J. Shackleton, Charles Turner, Polychronis C. Tzedakis, Isaac J. Winograd Jan 2002

Last Interglacial Climates, George J. Kukla, Michael L. Bender, Jacques-Louis De Beaulieu, Gerard Bond, Wallace S. Broecker, Piet Cleveringa, Joyce E. Gavin, Timothy D. Herbert, John Imbrie, Jean Jouzel, Lloyd D. Keigwin, Karen-Luise Knudsen, Jerry F. Mcmanus, Josef Merkt, Daniel R. Muhs, Helmut Muller, Richard Z. Poore, Stephen C. Porter, Guy Seret, Nicholas J. Shackleton, Charles Turner, Polychronis C. Tzedakis, Isaac J. Winograd

United States Geological Survey: Staff Publications

The last interglacial, commonly understood as an interval with climate as warm or warmer than today, is represented by marine isotope stage (MIS) 5e, which is a proxy record of low global ice volume and high sea level. It is arbitrarily dated to begin at approximately 130,000 yr B.P. and end at 116,000 yr B.P. with the onset of the early glacial unit MIS 5d. The age of the stage is determined by correlation to uranium–thorium dates of raised coral reefs. The most detailed proxy record of interglacial climate is found in the Vostok ice core where the temperature reached …

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Evidence For The Timing And Duration Of The Last Interglacial Period From High-Precision Uranium-Series Ages Of Corals On Tectonically Stable Coastlines, Daniel R. Muhs Jan 2002

Evidence For The Timing And Duration Of The Last Interglacial Period From High-Precision Uranium-Series Ages Of Corals On Tectonically Stable Coastlines, Daniel R. Muhs

United States Geological Survey: Staff Publications

The last interglacial period has a timing and duration that can be estimated from U-series dating of emergent, coral-bearing deposits on tectonically stable coastlines. High-precision dating from Bermuda, the Bahamas, Hawaii, and Australia suggests that the last interglacial period had a sea level at least as high as present from ~128,000 to 116,000 yr B.P. Sea level reached a near-present level more quickly after the close of the penultimate glacial period than at the close of the last glacial period and the duration of high sea level is longer than that implied by the deep-sea record.

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Timing And Warmth Of The Last Interglacial Period: New U-Series Evidence From Hawaii And Bermuda And A New Fossil Compilation For North America, Daniel R. Muhs, Kathleen R. Simmons, Bree Steinke Jan 2002

Timing And Warmth Of The Last Interglacial Period: New U-Series Evidence From Hawaii And Bermuda And A New Fossil Compilation For North America, Daniel R. Muhs, Kathleen R. Simmons, Bree Steinke

United States Geological Survey: Staff Publications

The timing and duration of the Last Interglacial period have been controversial, with some studies suggesting a relatively short duration that is orbitally forced and others suggesting a long duration that is at most only partly related to orbital forcing. New, high-precison thermal ionization mass spectrometric (TIMS) U-series ages of Last Interglacial corals from Hawaii and Bermuda test these competing hypotheses. Waimanalo Formation corals from slowly uplifting Oahu, Hawaii range in age from ~ 134 to ~ 113 ka, with most ages between ~ 125 and ~ 115 ka. Combined with published U-series ages from nearby Lanai, the data suggest …

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Radiocarbon Dating, Chronologic Framework, And Changes In Accumulation Rates Of Holocene Estuarine Sediments From Chesapeake Bay, Steven M. Colman, Pattie C. Baucom, John F. Bratton, Thomas M. Cronin, John P. Mcgeehin, Debra Willard, Andrew R. Zimmerman, Peter R. Vogt Jan 2002

Radiocarbon Dating, Chronologic Framework, And Changes In Accumulation Rates Of Holocene Estuarine Sediments From Chesapeake Bay, Steven M. Colman, Pattie C. Baucom, John F. Bratton, Thomas M. Cronin, John P. Mcgeehin, Debra Willard, Andrew R. Zimmerman, Peter R. Vogt

United States Geological Survey: Staff Publications

Rapidly accumulating Holocene sediments in estuaries commonly are difficult to sample and date. In Chesapeake Bay, we obtained sediment cores as much as 20min length and used numerous radiocarbon ages measured by accelerator mass spectrometry methods to provide the first detailed chronologies of Holocene sediment accumulation in the bay. Carbon in these sediments is a complex mixture of materials from a variety of sources. Analyses of different components of the sediments show that total organic carbon ages are largely unreliable, because much of the carbon (including coal) has been transported to the bay from upstream sources and is older than …

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Probability Of Nitrate Contamination Of Recently Recharged Groundwaters In The Conterminous United States, Bernard Nolan, Kerie Hitt, Barbara Ruddy Jan 2002

Probability Of Nitrate Contamination Of Recently Recharged Groundwaters In The Conterminous United States, Bernard Nolan, Kerie Hitt, Barbara Ruddy

United States Geological Survey: Staff Publications

A new logistic regression (LR) model was used to predict the probability of nitrate contamination exceeding 4 mg/L in predominantly shallow, recently recharged groundwaters of the United States. The new model contains variables representing (1) N fertilizer loading (p < 0.001), (2) percent cropland-pasture (p < 0.001), (3) natural log of human population density (p < 0.001), (4) percent well-drained soils (p < 0.001), (5) depth to the seasonally high water table (p < 0.001), and (6) presence or absence of unconsolidated sand and gravel aquifers (p =0.002). Observed and average predicted probabilities associated with deciles of risk are well correlated (r2 = 0.875), indicating that the LR model fits the data well. The likelihood of nitrate contamination is greater in areas with high N loading and well-drained surficial soils over unconsolidated sand and gravels. The LR model correctly predicted the status of nitrate contamination in 75% of wells in a validation data set. Considering all wells used in both calibration and …

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Seasonal Migration Of Columbia Spotted Frogs (Rana Luteiventris) Among Complementary Resources In A High Mountain Basin, David S. Pilliod, Charles R. Peterson, Peter I. Ritson Dec 2001

Seasonal Migration Of Columbia Spotted Frogs (Rana Luteiventris) Among Complementary Resources In A High Mountain Basin, David S. Pilliod, Charles R. Peterson, Peter I. Ritson

United States Geological Survey: Staff Publications

Information on how animals partition their activities and travel among complementary resources, such as breeding or overwintering habitats, is needed for species conservation. In a mountain basin at 2500 m elevation in central Idaho, we studied the habitat use and movement patterns of 736 marked and 87 radio-tagged Columbia spotted frogs (Rana luteiventris) from 1995 to 1998. The goals of this study were to (i) identify and characterize R. luteiventris breeding, summer foraging, and overwintering habitats, (ii) describe the movement patterns of juvenile, male, and female R. luteiventris among these resources, and (iii …

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Ecosystems And Immune Systems: Hierarchical Response Provides Resilience Against Invasions, Craig R. Allen Jun 2001

Ecosystems And Immune Systems: Hierarchical Response Provides Resilience Against Invasions, Craig R. Allen

United States Geological Survey: Staff Publications

Janssen (2001) provides the stimulus for thoughtful comparison and consideration of the ranges of responses exhibited by immune systems and ecological systems in the face of perturbations such as biological invasions. It may indeed be informative to consider the similarities of the responses to invasions exhibited by immune systems and ecological systems. Clearly, both types of systems share a general organizational structure with all other complex hierarchical systems. Their organization provides these systems with resilience. However, when describing the response of ecological-economic systems to invasions, Janssen emphasizes the human-economic response. I would like to expand on his comparison by focusing …

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Distributions Of Roosting Sandhill Cranes As Identified By Aerial Thermography, Tierny L. Parrish, Wayne A. Hubert, Stanley H. Anderson, Michael Pucherelli, Warren Mangus Jun 2001

Distributions Of Roosting Sandhill Cranes As Identified By Aerial Thermography, Tierny L. Parrish, Wayne A. Hubert, Stanley H. Anderson, Michael Pucherelli, Warren Mangus

United States Geological Survey: Staff Publications

We used aerial thermography to determine the location of sandhill crane (Grus canadensis) roosting sites during a single night over a 142-km reach of the Platte River, Nebraska. We assessed the influences of human disturbance features, screening of disturbance features by woody vegetation, distance to surrounding cropland of various types and channel width on distribution patterns of sandhill crane roosting sites with the aid of a geographic information system (GIS). We found that roosting sites were farther from bridges and paved roads than random points along the river channel; a visual woody screen mitigated the effect of bridges …

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Characteristics Of Nest Sites Of Northern Bobwhites In Western Oklahoma, Darrell E. Townsend Ii, Ronald E. Masters, Robert L. Lochmiller, David M. Leslie Jr., Stephen J. Demaso, Alan D. Peoples May 2001

Characteristics Of Nest Sites Of Northern Bobwhites In Western Oklahoma, Darrell E. Townsend Ii, Ronald E. Masters, Robert L. Lochmiller, David M. Leslie Jr., Stephen J. Demaso, Alan D. Peoples

United States Geological Survey: Staff Publications

Previous authors have described nesting habitat of the northern bobwhite (Colinus virginianus) throughout its range, but few have compared structural or compositional differences of vegetation between nest sites and random non-use sites, and successful and non-successful nests. From 1996-1998, we compared cover and structure of 85 plant species from 80 nest sites of northern bobwhite in western Oklahoma. Nest sites were consistently associated with greater structural complexity than what was available at random. Bobwhites selected nest sites with a greater coverage of grass (ca. 50%) and woody (ca. 20-30%) vegetation with a relatively low percentage of bare ground, …

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Locating Nests Of Birds In Grasslands From A Mobile Tower Blind, Thomas F. Fondell, Steven T. Hoekman, I. J. Ball Feb 2001

Locating Nests Of Birds In Grasslands From A Mobile Tower Blind, Thomas F. Fondell, Steven T. Hoekman, I. J. Ball

United States Geological Survey: Staff Publications

Locating nests of grassland passerines can be difficult, labor intensive, and disruptive to birds and vegetation. We developed a mobile tower blind for observing adult bird behavior and used it to locate nests in a western Montana grassland. We compared nest-search efficiency of behavioral observations from the tower versus the ground. Nests of savannah sparrow (Passerculus samhvichensis) were found in a higher proportion of territories searched from the tower (13/16 = 82%) than from the ground (4113 = 3 1%). Average search time for each nest found was lower from the tower (44 min) than from the ground …

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Occurrence And Potential Adverse Effects Of Semivolatile Organic Compounds In Streambed Sediment, United States, 1992–1995, Thomas J. Lopes, Edward T. Furlong Jan 2001

Occurrence And Potential Adverse Effects Of Semivolatile Organic Compounds In Streambed Sediment, United States, 1992–1995, Thomas J. Lopes, Edward T. Furlong

United States Geological Survey: Staff Publications

The occurrence and potential adverse effects of select semivolatile organic compounds (SVOCs) in streambed sediment were assessed at 536 sites in 20 major river basins across the United States from 1992 to 1995. Fifty-six SVOCs were detected at one or more sites, and one or more SVOCs were detected at 71% of sites. The northeastern and Great Lakes regions and large metropolitan areas have the highest SVOC concentrations. Polycyclic aromatic hydrocarbons (PAHs) were detected most frequently and at the highest concentrations. Concentrations of PAHs and phthalates were about 10 times higher at sites influenced by urban activities than at sites …

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Earthquake Stress Drop And Laboratory-Inferred Interseismic Strength Recovery, N. M. Beeler, S. H. Hickman, T. F. Wong Jan 2001

Earthquake Stress Drop And Laboratory-Inferred Interseismic Strength Recovery, N. M. Beeler, S. H. Hickman, T. F. Wong

United States Geological Survey: Staff Publications

We determine the scaling relationships between earthquake stress drop and recurrence interval t, that are implied by laboratory-measured fault strength.  We assume that repeating earthquakes can be simulated by stick-slip sliding using a spring and slider block model.  Simulations with static/kinetic strength, time-dependent strength, and rate- and state-variable dependent strength indicate that the relationship between loading velociety and recurrence intercal can be adequately described be the power law VL ∞ tnr, where n ≈ -1. Deviations from n≈ -1 arise from second order effects on strength, with n> -1 corresponding to apparent time-dependent …

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Regional Variations In Provenance And Abundance Of Ice-Rafted Clasts In Arctic Ocean Sediments: Implications For The Configuration Of Late Quaternary Oceanic And Atmospheric Circulation In The Arctic, R. L. Phillips, A. Grantz Jan 2001

Regional Variations In Provenance And Abundance Of Ice-Rafted Clasts In Arctic Ocean Sediments: Implications For The Configuration Of Late Quaternary Oceanic And Atmospheric Circulation In The Arctic, R. L. Phillips, A. Grantz

United States Geological Survey: Staff Publications

The composition and distribution of ice-rafted glacial erratics in late Quaternary sediments define the major current systems of the Arctic Ocean and identify two distinct continental sources for the erratics. In the southern Amerasia basin up to 70% of the erratics are dolostones and limestones (the Amerasia suite) that originated in the carbonate-rich Paleozoic terranes of the Canadian Arctic Islands. These clasts reached the Arctic Ocean in glaciers and were ice-rafted to the core sites in the clockwise Beaufort Gyre. The concentration of erratics decreases northward by 98% along the trend of the gyre from southeastern Canada basin to Makarov …

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Central Us Earthquake Catalog For Hazard Maps Of Memphis, Tennessee, Russell L. Wheeler, Charles S. Mueller Jan 2001

Central Us Earthquake Catalog For Hazard Maps Of Memphis, Tennessee, Russell L. Wheeler, Charles S. Mueller

United States Geological Survey: Staff Publications

An updated version of the catalog that was used for the current national probabilistic seismic-hazard maps would suffice for preduction of large-scale hazard maps of the Memphis urban area. Deaggregation maps provide guidance as to the area that a catalog for calculating Memphis hazard should cover. For the future, the Nuttli and local netword catalogs could be examined for earthquakes nor presenly included in the cataloge. Additional work on the aftershock removal might reduce hazard uncertainty. Graphs of decadal and annual earthquake rates suggest completeness at and above magnitude 3 for the last three or four decades. Any additional work …

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Major Herbicides In Ground Water: Results From The National Water-Quality Assessment, Jack . E. Barbash, Gail P. Thelin, Dana W. Kolpin, Robert J. Gilliom Jan 2001

Major Herbicides In Ground Water: Results From The National Water-Quality Assessment, Jack . E. Barbash, Gail P. Thelin, Dana W. Kolpin, Robert J. Gilliom

United States Geological Survey: Staff Publications

To improve understanding of the factors affecting pesticide occurrence in ground water, patterns of detection were examined for selected herbicides, based primarily on results from the National Water-Quality Assessment (NAWQA) program. The NAWQA data were derived from 2227 sites (wells and springs) sampled in 20 major hydro- logic basins across the USA from 1993 to 1995. Results are presented for six high-use herbicides—atrazine (2-chloro-4-ethylamino-6-iso-propylamino- s-triazine), cyanazine (2-[4-chloro-6-ethylamino-1,3,5-triazin-2-yl]amino]-2-methylpropionitrile), simazine (2-chloro-4,6-bis- [ethylamino]-s-triazine), alachlor (2-chloro-N-[2,6-diethylphenyl]-N- [methoxymethyl]acetamide), acetochlor (2-chloro-N-[ethoxymethyl]- N-[ 2-ethyl-6-methylphenyl]acetamide), and metolachlor (2-chloro-N- [2-ethyl-6-methylphenyl]-N-[2-methoxy-1-methylethyl]acetamide)— as well as for prometon (2,4-bis[isopropylamino]-6-methoxy-s-triazine), a nonagricultural herbicide detected frequently during the study. Concentrations were <1 μg L-1 at 98% …

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Impact Of Climate And Parent Material On Chemical Weathering In Loess-Derived Soils Of The Mississippi River Valley, Daniel R. Muhs, E. A. Bettis Iii, J. Been, J. P. Mcgeehin Jan 2001

Impact Of Climate And Parent Material On Chemical Weathering In Loess-Derived Soils Of The Mississippi River Valley, Daniel R. Muhs, E. A. Bettis Iii, J. Been, J. P. Mcgeehin

United States Geological Survey: Staff Publications

Peoria Loess-derived soils on uplands east of the Mississippi River the midcontinent of North America (Ruhe, 1969; Hall valley were studied from Louisiana to Iowa, along a south-to-north and Anderson, 2000), Alaska (Muhs et al., 2001), and gradient of decreasing precipitation and temperature. Major element China (Maher et al., 1994). Critical to paleoclimatic interanalyses of deep loess in Mississippi and Illinois show that the composi- pretations, using paleosols, are reliable climofunctions tion of the parent material is similar in the northern and southern for modern soils, which give an understanding of soil parts of the valley. We hypothesized that in …

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Inhibition Of Erythrocyte Δ- Aminolevulinic Acid Dehydratase (Alad) Activity In Fish From Waters Affects By Lead Smelters, Christopher J. Schmitt, Colleen A. Caldwell, Bill Olsen, Dave Serdar Jan 2001

Inhibition Of Erythrocyte Δ- Aminolevulinic Acid Dehydratase (Alad) Activity In Fish From Waters Affects By Lead Smelters, Christopher J. Schmitt, Colleen A. Caldwell, Bill Olsen, Dave Serdar

United States Geological Survey: Staff Publications

We assessed the effects on fish of lead (Pb) released to streams by smelters located in Trail, BC (Canada), E. Helena, MT, Herculaneum, MO, and Glover, MO. Fish were collected by electrofishing from sites located downstream of smelters and from reference sites. Blood from each fish was analyzed for δ-aminolevulinic acid dehydratase (ALAD) activity and hemoglobin (Hb), and samples of blood, liver, or carcass were analyzed for Pb, zinc (Zn), or both. Fish collected downstream of all four smelters sites had elevated Pb concentrations, decreased ALAD activity, or both relative to their respective reference sites. At E. Helena, fish from …

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Remnant Colloform Pyrite At The Haile Gold Deposit, South Carolina: A Textural Key To Genesis, Nora Foley, Robert A. Ayuso, Robert R. Seal Ii Jan 2001

Remnant Colloform Pyrite At The Haile Gold Deposit, South Carolina: A Textural Key To Genesis, Nora Foley, Robert A. Ayuso, Robert R. Seal Ii

United States Geological Survey: Staff Publications

Auriferous iron sulfide-bearing deposits of the Carolina slate belt have distinctive mineralogical and textural features—traits that provide a basis to construct models of ore deposition. Our identification of paragenetically early types of pyrite, especially remnant colloform, crustiform, and layered growth textures of pyrite containing electrum and pyrrhotite, establishes unequivocally that gold mineralization was coeval with deposition of host rocks and not solely related to Paleozoic tectonic events. Ore horizons at the Haile deposit, South Carolina, contain many remnants of early pyrite: (1) fine-grained cubic pyrite disseminated along bedding; (2) finegrained spongy, rounded masses of pyrite that may envelop or drape …

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2,3,7,8-Tetrachlorodibenzo-P-Dioxin Induces Apoptotic Cell Death And Cytochrome P4501a Expression In Developing Fundulus Heteroclitus Embryos, Barbara Holland Toomey, Susan Bello, Mark E. Hahn, Susannah Cantrell, Peggy Wright, Donald E. Tillitt, Richard T. Di Giulio Jan 2001

2,3,7,8-Tetrachlorodibenzo-P-Dioxin Induces Apoptotic Cell Death And Cytochrome P4501a Expression In Developing Fundulus Heteroclitus Embryos, Barbara Holland Toomey, Susan Bello, Mark E. Hahn, Susannah Cantrell, Peggy Wright, Donald E. Tillitt, Richard T. Di Giulio

United States Geological Survey: Staff Publications

Fundulus heteroclitus embryos were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) during early development using nanoinjection or water bath exposure. TCDD caused developmental abnormalities that included hemorrhaging, loss of vascular integrity, edema, stunted development and death. The LC50 and LD50 of TCDD for Fundulus embryos were ~19.7 ± 9.5 pg TCDD/µl (water bath) and 0.25 ± 0.09 ng TCDD/g embryo (nanoinjection). To identify a possible cause for these developmental abnormalities we analyzed the effects of TCDD on apoptotic cell death and cytochrome P4501A (CYP1A) expression in the embryos. TCDD exposure increased apoptotic cell death in several tissues including brain, …

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Origin Of Late Quaternary Dune Fields On The Southern High Plains Of Texas And New Mexico, Daniel R. Muhs, Vance T. Holliday Jan 2001

Origin Of Late Quaternary Dune Fields On The Southern High Plains Of Texas And New Mexico, Daniel R. Muhs, Vance T. Holliday

United States Geological Survey: Staff Publications

Mostly stabilized late Holocene eolian sands on the Southern High Plains of the United States were studied to determine their origins and to assess whether present dune stability depends more strongly on sediment supply, sediment availability, or transport limitations. Geomorphic, sedimentological, and geochemical trends indicate that late Holocene dunes formed under westerly paleowinds, broadly similar to those of today. Mineralogical and geochemical data indicate that the most likely source for the sands is not the Pecos River valley, but the Pleistocene Blackwater Draw Formation, an older, extensive eolian deposit in the region. These observations suggest that new sand is supplied …

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Vegetation And Paleoclimate Of The Last Interglacial Period, Central Alaska, Daniel R. Muhs, Thomas A. Ager, James E. Begét Jan 2001

Vegetation And Paleoclimate Of The Last Interglacial Period, Central Alaska, Daniel R. Muhs, Thomas A. Ager, James E. Begét

United States Geological Survey: Staff Publications

The last interglacial period is thought to be the last time global climate was signi"cantly warmer than present. New stratigraphic studies at Eva Creek, near Fairbanks, Alaska indicate a complex last interglacial record wherein periods of loess deposition alternated with periods of soil formation. The Eva Forest Bed appears to have formed about the time of or after deposition of the Old Crow tephra (dated to ~ 160 to ~ 120 ka), and is therefore correlated with the last interglacial period. Pollen, macrofossils, and soils from the Eva Forest Bed indicate that boreal forest was the dominant vegetation and precipitation …

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Evolution Of Soils On Quaternary Reef Terraces Of Barbados, West Lndies, Daniel R. Muhs Jan 2001

Evolution Of Soils On Quaternary Reef Terraces Of Barbados, West Lndies, Daniel R. Muhs

United States Geological Survey: Staff Publications

Soils on uplifted Quaternary reef terraces of Barbados, ~125,000 to ~700,000 yr old, form a climo-chronosequence and show changes in physical, chemical, and mineralogical properties with terrace age. Parent materials are dust derived from the Sahara, volcanic ash from the Lesser Antilles island arc, and detrital carbonate from the underlying reef limestone. Although some terrace soils are probably eroded, soils or their remnants are redder and more clay-rich with increasing terrace age. Profile-average Al2O3 and Fe2O3 content increases with terrace age, which partially reflects the increasing clay content, but dithionite-extractable Fe also increases with …

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Comparison Of Instream Methods For Measuring Hydrolic Conductivity In Sandy Streambeds, Matthew K. Landon, David L. Rus, F. Edwin Harvey Jan 2001

Comparison Of Instream Methods For Measuring Hydrolic Conductivity In Sandy Streambeds, Matthew K. Landon, David L. Rus, F. Edwin Harvey

United States Geological Survey: Staff Publications

Streambed hydraulic conductivity (K) values were determined at seven stream transects in the Platte River Basin in Nebraska using different instream measurement techniques.

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The Pacific Island Mapping Program Of The Us Geological Survey, Frank C. Whitmore Jr. Jan 2001

The Pacific Island Mapping Program Of The Us Geological Survey, Frank C. Whitmore Jr.

United States Geological Survey: Staff Publications

A little-known aspect of the U.S. Geological Survey history is its involvement in preparing terrain intelligence reports during World War II. The Survey's Military Geology Unit was in charge of compiling these reports on areas of possible military operations. Maps were the main part of' these studies; they were compiled from existing maps, geologic and soils literature, aerial and ground photographs, and travelers' accounts. Compiled geologic anti soils maps served as basic data for interpretative maps on such subjects as construction materials. water supply, road and airfield siting and construction, and cross-country movement by tanks.

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Evidence For Millennial-Scale Climate Change During Marine Isotope Stages 2 And 3 At Little Lake, Western Oregon, U.S.A., Laurie D. Grigg, Cathy Whitlock, Walter E. Dean Jan 2001

Evidence For Millennial-Scale Climate Change During Marine Isotope Stages 2 And 3 At Little Lake, Western Oregon, U.S.A., Laurie D. Grigg, Cathy Whitlock, Walter E. Dean

United States Geological Survey: Staff Publications

Pollen and geochemical data from Little Lake, western Oregon, suggest several patterns of millennial-scale environmental change during marine isotope stage (MIS) 2 (14,100–27,600 cal yr B.P.) and the latter part of MIS 3 (27,600–42,500 cal yr B.P.). During MIS 3, a series of transitions between warm- and cold-adapted taxa indicate that temperatures oscillated by ca. 2±–4±C every 1000–3000 yr. Highs and lows in summer insolation during MIS 3 are generally associated with the warmest and coldest intervals. Warm periods at Little Lake correlate with warm sea-surface temperatures in the Santa Barbara Basin. Changes in the strength of the subtropical high …

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Occurrence Of Cyanazine Compounds In Groundwater: Degradates More Prevalent Than The Parent Compound, Dana Kolpin, E. Michael Thurman, S. Michael Linhart Jan 2001

Occurrence Of Cyanazine Compounds In Groundwater: Degradates More Prevalent Than The Parent Compound, Dana Kolpin, E. Michael Thurman, S. Michael Linhart

United States Geological Survey: Staff Publications

A recently developed analytical method using liquid chromatography/mass spectrometry was used to investigate the occurrence of cyanazine and its degradates cyanazine acid (CAC), cyanazine amide (CAM), deethylcyanazine (DEC), and deethylcyanazine acid (DCAC) in groundwater. This research represents some of the earliest data on the occurrence of cyanazine degradates in groundwater. Although cyanazine was infrequently detected in the 64 wells across Iowa sampled in 1999, cyanazine degradates were commonly found during this study. The most frequently detected cyanazine compound was DCAC (32.8%) followed by CAC (29.7%), CAM (17.2%), DEC (3.1%), and cyanazine (3.1%). The frequency of detection for cyanazine or one …

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Effect Of Scale On The Behavior Of Atrazine In Surface Waters, Paul Capel, Steven Larson Jan 2001

Effect Of Scale On The Behavior Of Atrazine In Surface Waters, Paul Capel, Steven Larson

United States Geological Survey: Staff Publications

Field runoff is an important transport mechanism by which agricultural pesticides, including atrazine, move into the hydrologic environment. Atrazine is chosen because it is widely used, is transported in runoff relatively easily, is widely observed in surface waters, and has relatively little loss in the stream network. Data on runoff of atrazine from experimental plot and field studies is combined with annual estimates of load in numerous streams and rivers, resulting in a data set with 408 observations that span 14 orders of magnitude in area. The load as a percent of use (LAPU) on an annual basis is the …

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