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Intercontinental Migration Of Large Mammalian Carnivores: Earliest Occurrence Of The Old World Beardog Amphicyon (Carnivora, Amphicyonidae) In North America, Robert M. Hunt Jr. Jan 2003

Intercontinental Migration Of Large Mammalian Carnivores: Earliest Occurrence Of The Old World Beardog Amphicyon (Carnivora, Amphicyonidae) In North America, Robert M. Hunt Jr.

Department of Earth and Atmospheric Sciences: Faculty Publications

North American amphicyonid carnivorans are prominent members of the mid-Cenozoic terrestrial carnivore community during the late Eocene to late Miocene (Duchesnean to Clarendonian). Species range in size from <5 kg to >200 kg. Among the largest amphicyonids are Old and New World species of the genus Amphicyon: A. giganteus in Europe (18–~15? Ma) and Africa, A. ingens in North America (15.9–~14.2 Ma). Amphicyon first appears in the Oligocene of western Europe, surviving there until the late Miocene. Migration to Africa and North America takes place in the early Miocene. The genus occurs in the Arrisdrift fauna (Namibia) of southwest Africa, indicating migration south …


A Daily Soil Temperature Dataset And Soil Temperature Climatology Of The Contiguous United States, Q. Steven Hu, Yongjun Zheng Jan 2003

A Daily Soil Temperature Dataset And Soil Temperature Climatology Of The Contiguous United States, Q. Steven Hu, Yongjun Zheng

Department of Earth and Atmospheric Sciences: Faculty Publications

Although affected by atmospheric circulations, variations in soil temperature result primarily from the radiation and sensible and latent heat exchanges at the surface and heat transfer in the soils of different thermal properties. Thus, soil temperature and its variation at various depths are unique parameters that are useful in understanding both the surface energy processes and regional environmental and climatic conditions. Yet, despite the importance, long-term quality data of soil temperatures are not available for the United States. The goal of this study is to fill this data gap and to develop a soil temperature dataset from the historical data …


Butler County Test Hole Logs, Scott E. Summerside, Raymond R. Burchett Jan 2003

Butler County Test Hole Logs, Scott E. Summerside, Raymond R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Nuckolls County Test Hole Logs, Scott E. Summerside Jan 2003

Nuckolls County Test Hole Logs, Scott E. Summerside

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Seward County Test Hole Logs, Raymond R. Burchett, Frank A. Smith Jan 2003

Seward County Test Hole Logs, Raymond R. Burchett, Frank A. Smith

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Monitoring Trends In Bat Populations Of The United States And Territories: Status Of The Science And Recommendations For The Future, Thomas J. O'Shea, Michael A. Bogan, Laura E. Ellison Jan 2003

Monitoring Trends In Bat Populations Of The United States And Territories: Status Of The Science And Recommendations For The Future, Thomas J. O'Shea, Michael A. Bogan, Laura E. Ellison

United States Geological Survey: Staff Publications

Populations of bats (Order Chiroptera) are difficult to monitor. However, current recognition of the importance of bats to biodiversity, their ecological and economic value as ecosystem components, and their vulnerability to declines makes monitoring trends in their populations a much-needed cornerstone for their future management. We report findings and recommendations of a recent expert workshop on monitoring trends in bat populations in the United States and territories. We summarize selected case reports presented by others at the workshop, including reviews of methods and ongoing efforts to monitor a wide range of species of bats in a diverse array of situations. …


Public Knowledge And Perceptions Of Black-Tailed Prairie Dogs, Berton Lee Lamb, Kurt Cline Jan 2003

Public Knowledge And Perceptions Of Black-Tailed Prairie Dogs, Berton Lee Lamb, Kurt Cline

United States Geological Survey: Staff Publications

Black-tailed prairie dogs (Cynomys ludovicianus) historically occupied an 11-state region of the United States. We surveyed 1,900 residents (response rate 56%) of this region to understand citizen knowledge and perceptions about prairie dogs and their management. Those who have direct experience— e.g., those who live very close to prairie dog colonies or know the location of the nearest colony—have higher levels of knowledge. A significantly higher level of knowledge was documented among those who were politically active when compared with the general public. Those who found environmental issues difficult to understand were associated with lower knowledge. People with …


Nebraska Birds In Recorded History, Fritz L. Knopf Jan 2003

Nebraska Birds In Recorded History, Fritz L. Knopf

United States Geological Survey: Staff Publications

The critical image of historical perspective is lacking in much of conservation biology's dialogue on protecting biotic diversity. Some biologists offer that the vision for bird conservation on the Central Grasslands of North America is to secure at least fragments of the avian assemblage that coexisted with Native Americans when Europeans first arrived. Nowhere, however, has anyone really tried to re-create such a historical image in any biological arena, until now.


Differences In Habitat Use By Blanding’S Turtles, Emydoidea Blandingii, And Painted Turtles, Chysemys Picta, In The Nebraska Sandhills, R. Bruce Bury, David J. Germano Jan 2003

Differences In Habitat Use By Blanding’S Turtles, Emydoidea Blandingii, And Painted Turtles, Chysemys Picta, In The Nebraska Sandhills, R. Bruce Bury, David J. Germano

United States Geological Survey: Staff Publications

We sampled a variety of wetlands in the Nebraska sandhills at Valentine National Wildlife Refuge. Significantly more individuals of painted turtles (Chrysemys picta) occurred in lakes and open waters than in marshes or small ponds, and the opposite was true for Blanding’s turtles (Emydoidea blandingii). Besides this marked difference in habitat use, 46% of the captured E. blandingii in pond/marsh habitat were juveniles, but only 31.6% in lakes and open water. Current information suggests that marshes and small ponds are important habitat for juvenile turtles, especially Emydoidea blandingii.


Eolian Sand Transport Pathways In The Southwestern United States: Importance Of The Colorado River And Local Sources, Daniel R. Muhs, Richard L. Reynolds, Josh Been, Gary Skipp Jan 2003

Eolian Sand Transport Pathways In The Southwestern United States: Importance Of The Colorado River And Local Sources, Daniel R. Muhs, Richard L. Reynolds, Josh Been, Gary Skipp

United States Geological Survey: Staff Publications

Geomorphologists have long recognized that eolian sand transport pathways extend over long distances in desert regions. Along such pathways, sediment transport by wind can surmount topographic obstacles and cross major drainages. Recent studies have suggested that three distinct eolian sand transport pathways exist (or once existed) in the Mojave and Sonoran Desert regions of the southwestern United States. One hypothesized pathway is eolian sand transport from the eastern Mojave Desert of California into western Arizona, near Parker, and would require sand movement across what must have been at least a seasonally dry Colorado River valley. We tested this hypothesis by …


Where Are The Women Geoscience Professors?, Mary Anne Holmes, Suzanne O'Connel Jan 2003

Where Are The Women Geoscience Professors?, Mary Anne Holmes, Suzanne O'Connel

Department of Earth and Atmospheric Sciences: Faculty Publications

Compiles an extensive set of data on the status of women in the geosciences, identifying successful strategies for increasing diversity as well as obstacles that hinder efforts. The lessons learned and best practices that arise from this report will help geoscientists continue to increase the gender diversity of their community. Some of these lessons also provide insight into ways to improve the racial and ethnic diversity of the geosciences.


Evolution From A Conventional Well Field To A Riverbank-Filtration System, John D. North, Douglas J. Schnoebelen, Shelli Grapp, Roy E. Hesemann Jan 2003

Evolution From A Conventional Well Field To A Riverbank-Filtration System, John D. North, Douglas J. Schnoebelen, Shelli Grapp, Roy E. Hesemann

United States Geological Survey: Staff Publications

The City of Cedar Rapids is located in east-central Iowa and has a population of 121,000. The Cedar River alluvial aquifer is the sole source of drinking water for the City. Within the last few years, the Cedar River — which drains a major agricultural watershed — has experienced extended periods of elevated levels of nitrate and herbicides (notably, atrazine and its degradation byproducts) that were above the maximum contaminant level for drinking water. Fortunately, during these extended periods of compromised water quality in the river, RBF enabled the Cedar Rapids Water Department to obtain and treat adequate quantities of …


Ethylenediaminetetraacetic Acid Occurrence And Removal Through Bank Filtration In The Platte River, Nebraska, Jason R. Vogel, Larry B. Barber, Tyler B. Coplen, Ingrid M. Verstraeten, Thomas F. Speth, Jerry Obrist, Win Butler Jan 2003

Ethylenediaminetetraacetic Acid Occurrence And Removal Through Bank Filtration In The Platte River, Nebraska, Jason R. Vogel, Larry B. Barber, Tyler B. Coplen, Ingrid M. Verstraeten, Thomas F. Speth, Jerry Obrist, Win Butler

United States Geological Survey: Staff Publications

The USGS, USEPA, and City of Lincoln Water System (Nebraska) have conducted a study to determine the occurrence and removal of EDTA, NTA, and nonylphenol monoethoxycarboxylate to nonylphenol pentaethoxycarboxylate (NP1EC-NP5EC) in the hydrologic system at the City of Lincoln well field. The objective of the study is to evaluate the occurrence and removal of EDTA, NTA, and total nonylphenolpolyethoxycarboxylate (NPEC) by bank filtration at the City of Lincoln well field. This presentation will discuss removal during two sampling periods — May and August 2002 — based upon surface-water fractions in the collector well calculated using stable isotope ratios of hydrogen …


Quaternary Sedimentation And Subsidence History Of Lake Baikal, Siberia, Based On Seismic Stratigraphy And Coring, S. M. Colman, E. B. Karabanov, C. H. Nelson Iii Jan 2003

Quaternary Sedimentation And Subsidence History Of Lake Baikal, Siberia, Based On Seismic Stratigraphy And Coring, S. M. Colman, E. B. Karabanov, C. H. Nelson Iii

United States Geological Survey: Staff Publications

The long, continuous, high-latitude, stratigraphic record of Lake Baikal was deposited in three broad sedimentary environments, defined by high-resolution seismic-reflection and coring methods: (1) turbidite depositional systems, by far the most widespread, characterizing most of the margins and floors of the main basins of the lake, (2) large deltas of major drainages, and (3) tectonically or topographically isolated ridges and banks. Holocene sedimentation rates based on radiocarbon ages vary by more than an order of magnitude among these environments, from less than about 0.03 mm/yr on ridges and banks to more than about 0.3 mm/yr on basin floors. Extrapolating these …


Birth Of The Modern Chesapeake Bay Estuary Between 7.4 And 8.2 Ka And Implications For Global Sea-Level Rise, John F. Bratton, Steven M. Colman, E. Robert Thieler, Robert R. Seal Ii Jan 2003

Birth Of The Modern Chesapeake Bay Estuary Between 7.4 And 8.2 Ka And Implications For Global Sea-Level Rise, John F. Bratton, Steven M. Colman, E. Robert Thieler, Robert R. Seal Ii

United States Geological Survey: Staff Publications

Two major pulses of sea-level rise are thought to have taken place since the last glacial maximum – meltwater pulses (mwp) 1A (12 cal ka) and 1B (9.5 cal ka). Between mwp 1B and about 6 cal ka, many of the complex coastal ecosystems which ring the world’s oceans began to form. Here we report data for rhenium, carbon isotopes, total organic carbon, and fossil oysters from Chesapeake Bay which span the transition from fresh to brackish water conditions in the bay in the mid- Holocene. These data constrain sea-level change and resulting environmental change in the bay. They indicate …


Acquisition And Evaluation Of Thermodynamic Data For Morenosite-Retgersite Equilibria At 0.1 Mpa, I-Ming Chou, Robert R. Seal Ii Jan 2003

Acquisition And Evaluation Of Thermodynamic Data For Morenosite-Retgersite Equilibria At 0.1 Mpa, I-Ming Chou, Robert R. Seal Ii

United States Geological Survey: Staff Publications

Metal-sulfate salts in mine drainage environments commonly occur as solid solutions containing Fe, Cu, Mg, Zn, Al, Mn, Ni, Co, Cd, and other elements. Thermodynamic data for some of the endmember salts containing Fe, Cu, Zn, and Mg have been collected and evaluated previously, and the present study extends to the system containing Ni. Morenosite (NiSO4•7H2O)-retgersite (NiSO4•6H2O) equilibria were determined along five humidity buffer curves at 0.1 MPa and between 5 and 22 °C. Reversals along these humidity-buffer curves yield ln K = 17.58–6303.35/T, where K is the equilibrium constant, …


Effects Of Crustal Stresses On Fluid Transport In Fractured Rock: Case Studies From Northeastern And Southwestern Usa, Roger H. Morin, William Z. Savage Jan 2003

Effects Of Crustal Stresses On Fluid Transport In Fractured Rock: Case Studies From Northeastern And Southwestern Usa, Roger H. Morin, William Z. Savage

United States Geological Survey: Staff Publications

The link between stress and hydrologic properties was examined at two sites that are distinguished by different rock types and different stress states. This investigation is based upon the analysis and interpretation of geophysical logs obtained in water wells at the two locations. At the northeast site (Newark Basin), the hydrologic characteristics of sedimentary rocks are dependent upon the relationship to the current regional stress field of two primary types of orthogonal features that serve as preferential pathways for fluid flow. Subhorizontal bedding-plane partings are highly transmissive near the surface and delineate transversely isotropic fluid flow at shallow depths. With …


Apparent Break In Earthquake Scaling Due To Path And Site Effects On Deep Borehole Recordings, Satoshi Ide, Gregory C. Beroza, Stephanie G. Prejean, William L. Ellsworth Jan 2003

Apparent Break In Earthquake Scaling Due To Path And Site Effects On Deep Borehole Recordings, Satoshi Ide, Gregory C. Beroza, Stephanie G. Prejean, William L. Ellsworth

United States Geological Survey: Staff Publications

We reexamine the scaling of stress drop and apparent stress, rigidity times the ratio between seismically radiated energy to seismic moment, with earthquake size for a set of microearthquakes recorded in a deep borehole in Long Valley, California. In the first set of calculations, we assume a constant Q and solve for the corner frequency and seismic moment. In the second set of calculations, we model the spectral ratio of nearby events to determine the same quantities. We find that the spectral ratio technique, which can account for path and site effects or nonconstant Q, yields higher stress drops, …


Topographically Driven Groundwater Flow And The San Andreas Heat Flow Paradox Revisited, Demian M. Saffer, Barbara A. Bekins, Stephen Hickman Jan 2003

Topographically Driven Groundwater Flow And The San Andreas Heat Flow Paradox Revisited, Demian M. Saffer, Barbara A. Bekins, Stephen Hickman

United States Geological Survey: Staff Publications

Evidence for a weak San Andreas Fault includes borehole heat flow measurements that show no evidence for a frictionally generated heat flow anomaly and the inferred orientation of σ1 nearly perpendicular to the fault trace. Interpretations of the stress orientation data remain controversial, at least in close proximity to the fault, leading some researchers to hypothesize that the San Andreas Fault is, in fact, strong and that its thermal signature may be removed or redistributed by topographically driven groundwater flow in areas of rugged topography, such as typify the San Andreas Fault system. To evaluate this scenario, we use …


Stratigraphy, Geochronology, And Accretionary Terrane Settings Of Two Bronson Hill Arc Sequences, Northern New England, Robert H. Moench, John N. Aleinikoff Jan 2003

Stratigraphy, Geochronology, And Accretionary Terrane Settings Of Two Bronson Hill Arc Sequences, Northern New England, Robert H. Moench, John N. Aleinikoff

United States Geological Survey: Staff Publications

The Ammonoosuc Volcanics, Partridge Formation, and the Oliverian and Highlandcroft Plutonic Suites of the Bronson Hill anticlinorium (BHA) in axial New England are widely accepted as a single Middle to Late Ordovician magmatic arc that was active during closure of Iapetus. Mapping and U–Pb dating indicate, however, that the BHAcontains two volcano-sedimentary-intrusive sequences of probable opposite subduction polarity, here termed the Ammonoosuc and Quimby sequences.

The Ammonoosuc sequence is defined by the Middle Ordovician Ammonoosuc Volcanics near Littleton, NH, the type area, northeast to Milan, NH, and Oquossoc, ME; it also includes black slate of the Partridge Formation (C.bicornis …


Calibration Of Remotely Sensed, Coarse Resolution Ndvi To Co2 Fluxes In A Sagebrush–Steppe Ecosystem, Bruce K. Wylie, Douglas A. Johnson, Emilio Laca, Nicanor Z. Saliendra, Tagir G. Gilmanov, Bradley C. Reed, Larry L. Tieszen, Bruce B. Worstell Jan 2003

Calibration Of Remotely Sensed, Coarse Resolution Ndvi To Co2 Fluxes In A Sagebrush–Steppe Ecosystem, Bruce K. Wylie, Douglas A. Johnson, Emilio Laca, Nicanor Z. Saliendra, Tagir G. Gilmanov, Bradley C. Reed, Larry L. Tieszen, Bruce B. Worstell

United States Geological Survey: Staff Publications

The net ecosystem exchange (NEE) of carbon flux can be partitioned into gross primary productivity (GPP) and respiration (R). The contribution of remote sensing and modeling holds the potential to predict these components and map them spatially and temporally. This has obvious utility to quantify carbon sink and source relationships and to identify improved land management strategies for optimizing carbon sequestration. The objective of our study was to evaluate prediction of 14-day average daytime CO2 fluxes ( Fday) and nighttime CO2 fluxes (Rn) using remote sensing and other data. Fday …


An Approach For Mapping Large-Area Impervious Surfaces: Synergistic Use Of Landsat-7 Etm+ And High Spatial Resolution Imagery, Limin Yang, Chengquan Huang, Bruce K. Wylie, Michael J. Coan Jan 2003

An Approach For Mapping Large-Area Impervious Surfaces: Synergistic Use Of Landsat-7 Etm+ And High Spatial Resolution Imagery, Limin Yang, Chengquan Huang, Bruce K. Wylie, Michael J. Coan

United States Geological Survey: Staff Publications

A wide range of urban ecosystem studies, including urban climate, land use planning, and resource management, require current and accurate geospatial data of urban impervious surfaces. We developed an approach to quantify urban impervious surfaces as a continuous variable by using multisensor datasets. Subpixel percent impervious surfaces at 30-m resolution were mapped using a regression tree model. The utility, practicality, and affordability of the proposed method for large-area imperviousness mapping were tested over three spatial scales (Sioux Falls, South Dakota, Richmond, Virginia, and the Chesapeake Bay areas of the United States). Average error of predicted versus actual percent impervious surface …


Influence Of The Pacific Decadal Oscillation On The Climate Of The Sierra Nevada, California And Nevada, Larry Benson, Braddock Linsley, Joe Smoot, Scott Mensing, Steve Lund, Scott Stine, Andre Sarna-Wojcicki Jan 2003

Influence Of The Pacific Decadal Oscillation On The Climate Of The Sierra Nevada, California And Nevada, Larry Benson, Braddock Linsley, Joe Smoot, Scott Mensing, Steve Lund, Scott Stine, Andre Sarna-Wojcicki

United States Geological Survey: Staff Publications

Mono Lake sediments have recorded five major oscillations in the hydrologic balance between A.D. 1700 and 1941. These oscillations can be correlated with tree-ring-based oscillations in Sierra Nevada snowpack. Comparison of a tree-ring-based reconstruction of the Pacific Decadal Oscillation (PDO) index (D’Arrigo et al., 2001) with a coral-based reconstruction of Subtropical South Pacific sea-surface temperature (Linsley et al., 2000) indicates a high degree of correlation between the two records during the past 300 yr. This suggests that the PDO has been a pan-Pacific phenomena for at least the past few hundred years. Major oscillations in the hydrologic balance of the …


Age Of The Mono Lake Excursion And Associated Tephra, Larry Benson, Joseph Liddicoat, Joseph Smoot, Andrei Sarna-Wojcicki, Robert M. Negrini, Steve Lund Jan 2003

Age Of The Mono Lake Excursion And Associated Tephra, Larry Benson, Joseph Liddicoat, Joseph Smoot, Andrei Sarna-Wojcicki, Robert M. Negrini, Steve Lund

United States Geological Survey: Staff Publications

The Mono Lake excursion (MLE) is an important time marker that has been found in lake and marine sediments across much of the Northern Hemisphere. Dating of this event at its type locality, the Mono Basin of California, has yielded controversial results with the most recent effort concluding that the MLE may actually be the Laschamp excursion (Earth Planet. Sci. Lett. 197 (2002) 151). We show that a volcanic tephra (Ash #15) that occurs near the midpoint of the MLE has a date (not corrected for reservoir effect) of 28,620 ± 300 14C yr BP (~32,400 GISP2 yr BP) …


Rare-Earth Elements And Nd And Pb Isotopes As Source Indicators For Labrador Sea Clay-Size Sediments During Heinrich Event 2, Larry V. Benson, Don Barber, John T. Andrews, Howard E. Taylor, Paul Lamothe Jan 2003

Rare-Earth Elements And Nd And Pb Isotopes As Source Indicators For Labrador Sea Clay-Size Sediments During Heinrich Event 2, Larry V. Benson, Don Barber, John T. Andrews, Howard E. Taylor, Paul Lamothe

United States Geological Survey: Staff Publications

Elemental abundances and Nd and Pb isotope ratios were determined on samples from the carbonate-free, clay-size fractions of sediments from intervals above, within, and below Heinrich event 2 (H-2) in core HU87-9 from the Northwest Labrador Sea slope. In HU87-9, rare-earth element (REE) distributions and elemental concentrations within the H-2 event are distinct from those outside this event. ɛNd(0) and 206Pb/204Pb data also indicate different values for sediments deposited within and outside the H-2 event. Comparisons of REE patterns from the H-2 interval with those from bedrock units in Baffin Island, northern Quebec, and Labrador …


Response Of North American Great Basin Lakes To Dansgaard–Oeschger Oscillations, Larry Benson, Steve Lund, Robert M. Negrini, Braddock Linsley, Mladen Zic Jan 2003

Response Of North American Great Basin Lakes To Dansgaard–Oeschger Oscillations, Larry Benson, Steve Lund, Robert M. Negrini, Braddock Linsley, Mladen Zic

United States Geological Survey: Staff Publications

We correlate oscillations in the hydrologic and/or cryologic balances of four Great Basin surface-water systems with Dansgaard– Oeschger (D–O) events 2–12. This correlation is relatively strong at the location of the magnetic signature used to link the lake records, but becomes less well constrained with distance/time from the signature. Comparison of proxy glacial and hydrologic records from Owens and Pyramid lakes indicates that Sierran glacial advances occurred during times of relative dryness. If our hypothesized correlation between the lake-based records and the GISP2 δ18O record is correct, it suggests that North Atlantic D–O stades …


Aeolian Cliff-Top Deposits And Buried Soils In The White River Badlands, South Dakota, Usa, J. Elmo Rawling Iii, Glen G. Fredlund, Shannon Mahan Jan 2003

Aeolian Cliff-Top Deposits And Buried Soils In The White River Badlands, South Dakota, Usa, J. Elmo Rawling Iii, Glen G. Fredlund, Shannon Mahan

United States Geological Survey: Staff Publications

Aeolian deposits in the North American Great Plains are important sources of Holocene palaeoenvironmental records. Although there are extensive studies on loess and dune records in the region, little is known about records in aeolian cliff-top deposits. These are common on table (mesa) edges in the White River Badlands. These sediments typically have loam and sandy-loam textures with dominantly very fine sand, 0.5–1% organic carbon and 0.5–5% CaCO3. Some of these aeolian deposits are atypically coarse and contain granules and fine pebbles. Buried soils within these deposits are weakly developed with A-C and A-AC-C profiles. Beneath these are …


New Record Of The Rare Emballonurid Bat Centronycteris Centralis Thomas, 1912 In Costa Rica, With Notes On Feeding Habits, Neal Woodman Jan 2003

New Record Of The Rare Emballonurid Bat Centronycteris Centralis Thomas, 1912 In Costa Rica, With Notes On Feeding Habits, Neal Woodman

United States Geological Survey: Staff Publications

The shaggy sac-winged bat, Centronycteris centralis (Chiroptera: Emballonuridae), occurs mainly in lowland forests from Veracruz, Mexico, to Peru, although it has been reported from elevations as high at 1450 m in Panama (Simmons and Handley 1998; Hice and Solari 2002). Most captures of the species are of single individuals, and throughout its distribution, this bat is rare and poorly-known (Emmons 1997; Reid 1997; Simmons and Handley 1998). Centronycteris centralis generally has been assumed to be an aerial insectivore, capturing flying insects on the wing (Starrett and Casebeer 1968; Wilson 1973; Timm et al. 1989; LaVal and Rodrı´guez 2002). However, direct …


Quaternary Loess-Paleosol Sequences As Examples Of Climate-Driven Sedimentary Extremes, Daniel R. Muhs, E. Arthur Bettis Iii Jan 2003

Quaternary Loess-Paleosol Sequences As Examples Of Climate-Driven Sedimentary Extremes, Daniel R. Muhs, E. Arthur Bettis Iii

United States Geological Survey: Staff Publications

Loess is a widespread, wind-transported, silt-dominated deposit that contains geologic archives of atmospheric circulation and paleoclimate on continents. Loess may cover as much as 10% of the Earth’s land surface. It is composed mainly of quartz, feldspars, and clay minerals, with varying amounts of carbonate minerals. The geochemistry of loess differs from region to region, depending on source materials, but all loess is very high in SiO2 with lesser amounts of other major elements. Trends in loess downwind from source areas include systematic decreases in thickness and amounts of sand and coarse silt, and increases in amounts of fine silt …


Variability Of Metals In Soils In The Sudbury Area (Ontario), Vera Spektor Jan 2003

Variability Of Metals In Soils In The Sudbury Area (Ontario), Vera Spektor

Theses and Dissertations (Comprehensive)

Industrial development influences the natural and human environment. At the local scale, the most intensive industrial pollution is in the area of factories and industrial centers. Industrial pollution is concentrated in soil and vegetation (then, using water systems and trophic chains it may enter all ecosystem components). The industrial pollution of the Sudbury region includes mostly sulfur dioxide and heavy metals. The main goal of this study was to examine spatial variability in metal distribution in soil for the Sudbury area. Objectives of the work were to describe metal distribution depending on geographic factors such as topographic location, vegetation cover, …