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United States Geological Survey: Staff Publications

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Full-Text Articles in Earth Sciences

Structure And Properties Of The San Andreas Fault In Central California: Recent Results From The Safod Experiment, Stephen Hickman, Mark D. Zoback, William Ellsworth, Naomi Boness, Peter Malin, Steven Roecker, Clifford Thurber Jan 2007

Structure And Properties Of The San Andreas Fault In Central California: Recent Results From The Safod Experiment, Stephen Hickman, Mark D. Zoback, William Ellsworth, Naomi Boness, Peter Malin, Steven Roecker, Clifford Thurber

United States Geological Survey: Staff Publications

The San Andreas Fault Observatory at Depth (SAFOD) is a 3.2-km-deep borehole observatory drilled into the San Andreas fault zone at seismogenic depths to study directly the physical and chemical processes controlling faulting and earthquake generation.  SAFOD forms one component of EarthScope, a major Earth Science facility program of the U.S. National Science Foundation; the other two funded components are U.S. Array, a continental-scale seismic network, and the Plate Boundry Observatory, an extensive network of GOS receivers and strainmeters deployed acorss the western U.S. SAFOD is being conducted in collaboration with the U.S. Geological Survey and the International Continental Scientific …

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Seismology Inside The Fault Zone: Applications To Fault-Zone Properties And Rupture Dynamics, William L. Ellsworth, Peter E. Malin, Kazutoshi Imanishi, Steven W. Roecker, Robert Nadeau, Volder Oye, Clifford H. Thurber, Felix Waldhauser, Namoi L. Boness, Stephen H. Hickman, Mark D. Zoback Jan 2007

Seismology Inside The Fault Zone: Applications To Fault-Zone Properties And Rupture Dynamics, William L. Ellsworth, Peter E. Malin, Kazutoshi Imanishi, Steven W. Roecker, Robert Nadeau, Volder Oye, Clifford H. Thurber, Felix Waldhauser, Namoi L. Boness, Stephen H. Hickman, Mark D. Zoback

United States Geological Survey: Staff Publications

A central goal of seismology is to understand the physics of earthquakes and other sources of seismic waves in the Earth. We would like to understand how dynamic instabilities are nucleated, how they evolve in space and time, and how they come to rest. To achieve this goal, we need observations that are truly broadband with respect to source process time scales. Because the high-frequency limit of a seismogram directly controls the spatial scale at which we can resolve these processes, the requirement for “broadband” means bandwidth that is sufficient to record the shortest pulse produced by the physical system …

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Stress Orientations Of Taiwan Chelungpu-Fault Drilling Project (Tcdp) Hole-A As Observed From Geophysical Logs, Hung-Yu Wu, Kuo-Fong Ma, Mark Zoback, Naomi Boness, Hisao Ito, Jih-Hao Hung, U.S. Geological Survey Jan 2007

Stress Orientations Of Taiwan Chelungpu-Fault Drilling Project (Tcdp) Hole-A As Observed From Geophysical Logs, Hung-Yu Wu, Kuo-Fong Ma, Mark Zoback, Naomi Boness, Hisao Ito, Jih-Hao Hung, U.S. Geological Survey

United States Geological Survey: Staff Publications

The Taiwan Chelungpu-fault Drilling Project (TCDP) drilled a 2-km-deep research borehole to investigate the structure and mechanics of the Chelungpu Fault that ruptured in the 1999 Mw 7.6 Chi-Chi earthquake. Geophysical logs of the TCDP were carried out over depths of 500–1900 m, including Dipole Sonic Imager (DSI) logs and Formation Micro Imager (FMI) logs in order to identify bedding planes, fractures and shear zones. From the continuous core obtained from the borehole, a shear zone at a depth of 1110 meters is interpreted to be the Chelungpu fault, located within the Chinshui Shale, which extends from 1013 to …

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Airborne Dust Transport To The Eastern Pacific Ocean Off Southern California: Evidence From San Clemente Island, Daniel R. Muhs, James Budahn, Marith Reheis, Jossh Beann, Gary Skipp, Eric Fisher Jan 2007

Airborne Dust Transport To The Eastern Pacific Ocean Off Southern California: Evidence From San Clemente Island, Daniel R. Muhs, James Budahn, Marith Reheis, Jossh Beann, Gary Skipp, Eric Fisher

United States Geological Survey: Staff Publications

Islands are natural dust traps, and San Clemente Island, California, is a good example. Soils on marine terraces cut into Miocene andesite on this island are clay-rich Vertisols or Alfisols with vertic properties. These soils are overlain by silt-rich mantles, 5–20 cm thick, that contrast sharply with the underlying clay-rich subsoils. The silt mantles have a mineralogy that is distinct from the island bedrock. Silt mantles are rich in quartz, which is rare in the island andesite. The clay fraction of the silt mantles is dominated by mica, also absent from local andesite, and contrasts with the subsoils, dominated by …

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Comparison Of Local- To Regional-Scale Estimates Of Ground-Water Recharge In Minnesota, Usa, Geoffrey N. Delin, Richard W. Healy, David L. Lorenz, John R. Nimmo Jan 2007

Comparison Of Local- To Regional-Scale Estimates Of Ground-Water Recharge In Minnesota, Usa, Geoffrey N. Delin, Richard W. Healy, David L. Lorenz, John R. Nimmo

United States Geological Survey: Staff Publications

Regional ground-water recharge estimates for Minnesota were compared to estimates made on the basis of four local- and basin-scale methods. Three local-scale methods (unsaturated-zone water balance, water-table fluctuations (WTF) using three approaches, and age dating of ground water) yielded point estimates of recharge that represent spatial scales from about 1 to about 1000 m2. A fourth method (RORA, a basin-scale analysis of streamflow records using a recession-curve-displacement technique) yielded recharge estimates at a scale of 10–1000s of km2. The RORA basin-scale recharge estimates were regionalized to estimate recharge for the entire State of Minnesota on the …

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Microbial Sulfate Reduction And Metal Attenuation In Ph 4 Acid Mine Water, Clinton D. Church, Richard T. Wilkin, Charles N. Alpers, Robert O. Rye, R. Blaine Mccleskey Jan 2007

Microbial Sulfate Reduction And Metal Attenuation In Ph 4 Acid Mine Water, Clinton D. Church, Richard T. Wilkin, Charles N. Alpers, Robert O. Rye, R. Blaine Mccleskey

United States Geological Survey: Staff Publications

Sediments recovered from the flooded mine workings of the Penn Mine, a Cu-Zn mine abandoned since the early 1960s, were cultured for anaerobic bacteria over a range of pH (4.0 to 7.5). The molecular biology of sediments and cultures was studied to determine whether sulfate-reducing bacteria (SRB) were active in moderately acidic conditions present in the underground mine workings. Here we document multiple, independent analyses and show evidence that sulfate reduction and associated metal attenuation are occurring in the pH-4 mine environment. Waterchemistry analyses of the mine water reveal: (1) preferential complexation and precipitation by H2S of Cu …

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Responses Of Pond-Breeding Amphibians To Wildfire: Short-Term Patterns In Occupancy And Colonization, Blake R. Hossack, Paul Stephen Corn Dec 2006

Responses Of Pond-Breeding Amphibians To Wildfire: Short-Term Patterns In Occupancy And Colonization, Blake R. Hossack, Paul Stephen Corn

United States Geological Survey: Staff Publications

Wildland fires are expected to become more frequent and severe in many ecosystems, potentially posing a threat to many sensitive species. We evaluated the effects of a large, stand-replacement wildfire on three species of pond-breeding amphibians by estimating changes in occupancy of breeding sites during the three years before and after the fire burned 42 of 83 previously surveyed wetlands. Annual occupancy and colonization for each species was estimated using recently developed models that incorporate detection probabilities to provide unbiased parameter estimates. We did not find negative effects of the fire on the occupancy or colonization rates of the long-toed …

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Fate Of Fish Production In A Seasonally Flooded Saltmarsh, Philip W. Stevens, Clay L. Montague, Kenneth J. Sulak Dec 2006

Fate Of Fish Production In A Seasonally Flooded Saltmarsh, Philip W. Stevens, Clay L. Montague, Kenneth J. Sulak

United States Geological Survey: Staff Publications

Although saltmarshes are thought to enhance the productivity of open estuarine water, the mechanism by which energy transfer occurs has been debated for decades. One possible mechanism is the transfer of saltmarsh production to estuarine waters by vagile fishes and invertebrates. Monthly estimates of fish standing stock, net fish ingress, and predation were used to develop a bio-mass budget to estimates annual production of fishes and the relative yield to predatory fish, birds, and direct migration to the estuary. Annual production of saltmarsh fishes was estimated to 31.0 gm-2 saltmarsh, which falls within the range of previously reported values …

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The Legacy Of Leaded Gasoline In Bottom Sediment Of Small Rural Reservoirs, Kyle E. Juracek, Andrew C. Ziegler Oct 2006

The Legacy Of Leaded Gasoline In Bottom Sediment Of Small Rural Reservoirs, Kyle E. Juracek, Andrew C. Ziegler

United States Geological Survey: Staff Publications

The historical and ongoing lead (Pb) contamination caused by the 20th-century use of leaded gasoline was investigated by an analysis of bottom sediment in eight small rural reservoirs in eastern Kansas, USA. For the reservoirs that were completed before or during the period of maximum Pb emissions from vehicles (i.e., the 1940s through the early 1980s) and that had a major highway in the basin, increased Pb concentrations reflected the pattern of historical leaded gasoline use. For at least some of these reservoirs, residual Pb is still being delivered from the basins. There was no evidence of increased Pb deposition …

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Deep-Water Antipatharians: Proxies Of Environmental Change, B. Williams, M.J. Risk, S.W. Ross, K.J. Sulak Sep 2006

Deep-Water Antipatharians: Proxies Of Environmental Change, B. Williams, M.J. Risk, S.W. Ross, K.J. Sulak

United States Geological Survey: Staff Publications

Deep-water (307–697 m) antipatharian (black coral) specimens were collected from the southeastern continental slope of the United States and the north-central Gulf of Mexico. The sclerochronology of the specimens indicates that skeletal growth takes place by formation of concentric coeval layers. We used 210Pb to estimate radial growth rate of two specimens, and to establish that they were several centuries old. Bands were delaminated in KOH and analyzed for carbon and nitrogen stable isotopes. Carbon values ranged from _16.4‰ to _15.7‰; the oldest specimen displayed the largest range in values. Nitrogen values ranged from 7.7‰ to 8.6‰. …

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Anguilliform Larvae Collected Off North Carolina, Steve W. Ross, Tara L. Casazza, Andrea M. Quattrini, Kenneth J. Sulak Jul 2006

Anguilliform Larvae Collected Off North Carolina, Steve W. Ross, Tara L. Casazza, Andrea M. Quattrini, Kenneth J. Sulak

United States Geological Survey: Staff Publications

The distinctive larval stage of eels (leptocephalus) facilitates dispersal through prolonged life in the open ocean. Leptocephali are abundant and diverse off North Carolina, yet data on distributions and biology are lacking. The water column (from surface to 1,293 m) was sampled in or near the Gulf Stream off Cape Hatteras, Cape Lookout, and Cape Fear, North Carolina during summer through fall of 1999–2005, and leptocephali were collected by neuston net, plankton net, Tucker trawl, and dip net. Additional samples were collected nearly monthly from a transect across southern Onslow Bay, North Carolina (from surface to 91 m) from April …

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Sprawl And The Resilience Of Humans And Nature: An Introduction To The Special Feature, Craig R. Allen Jun 2006

Sprawl And The Resilience Of Humans And Nature: An Introduction To The Special Feature, Craig R. Allen

United States Geological Survey: Staff Publications

Human-driven change in land use and land cover is an accelerating global phenomenon with far-reaching implications for food production, forest and water resources, the climate, and biogeochemical cycles (Foley et al. 2005). It affects the amount and configuration of habitat available for animals ranging from soil nematodes to elephants. It affects the provision of ecological goods and services for human beings. It affects the processes and function of ecosystems.

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Discontinuities In Ecological Data, Craig R. Allen Apr 2006

Discontinuities In Ecological Data, Craig R. Allen

United States Geological Survey: Staff Publications

Historically, ecology has focused on continuous distributions and smooth transitions. Only recently have discontinuities and thresholds become an explicit focus in some areas of ecology, especially in the realm of complex systems. The study of animal body mass distributions has been recognized for its potential to provide insight into the underlying processes shaping animal communities. Hutchinson (1) formalized the understanding of species niches and the potential for competition to shape body mass distributions. However, despite a long history of theoretical and empirical pursuit, the mechanisms driving patterns in body mass distributions remain poorly understood. The work of Scheffer and van …

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Acoustic Stratigraphy Of Bear Lake, Utah–Idaho—Late Quaternary Sedimentation Patterns In A Simple Half-Graben, Steven M. Colman Jan 2006

Acoustic Stratigraphy Of Bear Lake, Utah–Idaho—Late Quaternary Sedimentation Patterns In A Simple Half-Graben, Steven M. Colman

United States Geological Survey: Staff Publications

A277-km network of high-resolution seismic-reflection profiles, supplemented with a sidescan-sonar mosaic of the lake floor, was collected in Bear Lake, Utah–Idaho, in order to explore the sedimentary framework of the lake’s paleoclimate record. The acoustic stratigraphy is tied to a 120 m deep, continuously cored drill hole in the lake. Based on the age model for the drill core, the oldest continuously mapped acoustic reflector in the data set has an age of about 100 ka, although older sediments were locally imaged.

The acoustic stratigraphy of the sediments below the lake indicates that the basin developed primarily as a simple …

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Spring Census Of Mid-Continent Sandhill Cranes Using Aerial Infrared Videography, Paul Kinzel, Jonathan Nelson, Randolph Parker, Lawrence Davis Jan 2006

Spring Census Of Mid-Continent Sandhill Cranes Using Aerial Infrared Videography, Paul Kinzel, Jonathan Nelson, Randolph Parker, Lawrence Davis

United States Geological Survey: Staff Publications

Aerial infrared videography was used to map spatial distributions of nocturnal sandhill crane (Grus canadensis) flocks and determine crane densities within roosts as an alternative to the currently used diurnal photo-corrected ocular transect method to estimate the size of the midcontinental population. The densities determined from samples taken over the course of a night show variability. Densities measured early in the night (2100 to 2300 hrs) were generally lower than those measured in the time period after midnight and up until cranes prepared to depart their roosts before sunrise. This suggests that cranes may be more active early …

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Widespread Presence Of Naturally Occurring Perchlorate In High Plains Of Texas And New Mexico, Srinath Rajagopalan, Todd Anderson, Lynne Fahlquist, Ken Rainwater, Moira Ridley, W. Andrew Jackson Jan 2006

Widespread Presence Of Naturally Occurring Perchlorate In High Plains Of Texas And New Mexico, Srinath Rajagopalan, Todd Anderson, Lynne Fahlquist, Ken Rainwater, Moira Ridley, W. Andrew Jackson

United States Geological Survey: Staff Publications

Perchlorate (ClO4-) occurrence in groundwater has previously been linked to industrial releases and the historic use of Chilean nitrate fertilizers. However, recently a number of occurrences have been identified for which there is no obvious anthropogenic source. Groundwater from an area of 155 000 km2 in 56 counties in northwest Texas and eastern New Mexico is impacted by the presence of ClO4-. Concentrations were generally low (<4 ppb), although some areas are impacted by concentrations up to 200 ppb. ClO4- distribution is not related to well type (public water system, domestic, agricultural, or water-table monitoring) or aquifer (Ogallala, Edward Trinity High Plains, Edwards Trinity …

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Simulation Of Solute Movement Through Wellbores To Characterize Public Supply Well Contaminant Vulnerability In The High Plains Aquifer, York, Nebraska, Brian R. Clark, Matthew K. Landon, Leon J. Kauffman, George Z. Hornberger Jan 2006

Simulation Of Solute Movement Through Wellbores To Characterize Public Supply Well Contaminant Vulnerability In The High Plains Aquifer, York, Nebraska, Brian R. Clark, Matthew K. Landon, Leon J. Kauffman, George Z. Hornberger

United States Geological Survey: Staff Publications

A ground-water flow and transport model simulating contaminant movement to public supply wells in the High Plains aquifer near York, Nebraska was developed as part of the U.S. Geological Survey National Water-Quality Assessment Program. Water-quality samples were collected from wells screened in unconfined and confined units. Samples collected from a public supply well and selected monitoring wells completed in the confined aquifer have chemistry and age-tracer concentrations consistent with a mix of young water from unconfined recharge areas combined with relatively older confined aquifer water. These results imply that there are preferential flow paths that permit shallow recharge water and …

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Change In Atmospheric Mineral Aerosols In Response To Climate: Last Glacial Period, Preindustrial, Modern, And Doubled Carbon Dioxide Climates, Natalie M. Mahowald, Daniel R. Muhs, Samuel Levis, Philip J. Rasch, Masaru Yoshioka, Charles S. Zender, Chao Luo Jan 2006

Change In Atmospheric Mineral Aerosols In Response To Climate: Last Glacial Period, Preindustrial, Modern, And Doubled Carbon Dioxide Climates, Natalie M. Mahowald, Daniel R. Muhs, Samuel Levis, Philip J. Rasch, Masaru Yoshioka, Charles S. Zender, Chao Luo

United States Geological Survey: Staff Publications

Desert dust simulations generated by the National Center for Atmospheric Research’s Community Climate System Model for the current climate are shown to be consistent with present day satellite and deposition data. The response of the dust cycle to last glacial maximum, preindustrial, modern, and doubled-carbon dioxide climates is analyzed. Only natural (non-land use related) dust sources are included in this simulation.

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Historical And Current Status Of Elk In Kansas, Jonathan M. Conard, Philip S. Gipson, Matt Peek Jan 2006

Historical And Current Status Of Elk In Kansas, Jonathan M. Conard, Philip S. Gipson, Matt Peek

United States Geological Survey: Staff Publications

Elk (Cervus elaphus) historically occurred throughout Kansas but were extirpated from the state around 1890. Free-ranging elk populations were reestablished in Kansas through reintroduction efforts on Cimarron National Grasslands from 1981-1990, and on Fort Riley Military Installation from 1986-1994. Current elk distributions in the state have not been published following these reintroduction efforts. The current and historical distribution of this species in Kansas is described.

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Measuring Groundwater–Surface Water Interaction And Its Effect On Wetland Stream Benthic Productivity, Trout Lake Watershed, Northern Wisconsin, Usa, Randall J. Hunt, Mac Strand, John F. Walker Jan 2006

Measuring Groundwater–Surface Water Interaction And Its Effect On Wetland Stream Benthic Productivity, Trout Lake Watershed, Northern Wisconsin, Usa, Randall J. Hunt, Mac Strand, John F. Walker

United States Geological Survey: Staff Publications

Measurements of groundwater–surface water exchange at three wetland stream sites were related to patterns in benthic productivity as part of the US Geological Survey’s Northern Temperate Lakes–Water, Energy and Biogeochemical Budgets (NTL–WEBB) project. The three sites included one high groundwater discharge (HGD) site, one weak groundwater discharge (WGD) site, and one groundwater recharge (GR) site. Large upward vertical gradients at the HGD site were associated with smallest variation in head below the stream and fewest gradient reversals between the stream and the groundwater beneath the stream, and the stream and the adjacent streambank. The WGD site had the highest number …

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Taxonomic Considerations In Listing Subspecies Under The U.S. Endangered Species Act, Susan M. Haig, Erik A. Beever, Steven M. Chambers, Hope M. Draheim, Bruce D. Dugger, Susie M. Dunham, Elise Elliott-Smith, Joseph B. Fontaine, Dylan C. Kesler, Brian J. Knaus, Iara F. Lopes, Pete Loschl, Thomas D. Mullins, Lisa M. Sheffield Jan 2006

Taxonomic Considerations In Listing Subspecies Under The U.S. Endangered Species Act, Susan M. Haig, Erik A. Beever, Steven M. Chambers, Hope M. Draheim, Bruce D. Dugger, Susie M. Dunham, Elise Elliott-Smith, Joseph B. Fontaine, Dylan C. Kesler, Brian J. Knaus, Iara F. Lopes, Pete Loschl, Thomas D. Mullins, Lisa M. Sheffield

United States Geological Survey: Staff Publications

The U.S. Endangered Species Act (ESA) allows listing of subspecies and other groupings below the rank of species. This provides the U.S. Fish and Wildlife Service and the National Marine Fisheries Service with a means to target the most critical unit in need of conservation. Although roughly one-quarter of listed taxa are subspecies, these management agencies are hindered by uncertainties about taxonomic standards during listing or delisting activities. In a review of taxonomic publications and societies, we found few subspecies lists and none that stated standardized criteria for determining subspecific taxa. Lack of criteria is attributed to a centuries-old debate …

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Conserving Biodiversity In Human-Dominated Landscapes, Dale D. Goble, J. Michael Scott, Frank W. Davis Jan 2006

Conserving Biodiversity In Human-Dominated Landscapes, Dale D. Goble, J. Michael Scott, Frank W. Davis

United States Geological Survey: Staff Publications

The two volumes of The Endangered Species Act at Thirty look backward to evaluate the effectiveness of the act over its first three decades (Wilcove and McMillan 2006; Scott et al. 2006, chap. 2; Goble, this volume; Svancara, this volume; Callicott, this volume; Norton, this volume) and also forward to suggest how it can be used as a cornerstone for conserving biological diversity in increasingly human-dominated landscapes (Davis et al. 2006; Bean 2006). The chapters in part 2 of this volume, for example, appraise the science of the 1990s and 2000s at both the large scale (Lomolino, this volume; Naeem …

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Isotope Sourcing Of Prehistoric Willow And Tule Textiles Recovered From Western Great Basin Rock Shelters And Caves: Proof Of Concept, Larry V. Benson, E. M. Hattori, H. E. Taylor, S. R. Poulson, E. A. Jolie Jan 2006

Isotope Sourcing Of Prehistoric Willow And Tule Textiles Recovered From Western Great Basin Rock Shelters And Caves: Proof Of Concept, Larry V. Benson, E. M. Hattori, H. E. Taylor, S. R. Poulson, E. A. Jolie

United States Geological Survey: Staff Publications

Isotope and trace-metal analyses were used to determine the origin of plants used to manufacture prehistoric textiles (basketry and matting) from archaeological sites in the western Great Basin. Research focused on strontium (87Sr/86Sr) and oxygen (18O/16O) isotope ratios of willow (Salix sp.) and tule (Schoenoplectus sp.), the dominant raw materials in Great Basin textiles. The oxygen-isotope data indicated that the willow and tule used to produce the textiles were harvested from the banks of rivers or in marshes characterized by flowing water and not from lakes or sinks. The strontium-isotope …

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Contact Zone Permeability At Intrusion Boundaries: New Results From Hydraulic Testing And Geophysical Logging In The Newark Rift Basin, New York, Usa, Jurg M. Matter, D. S. Goldberg, Roger H. Morin, M. Stute Jan 2006

Contact Zone Permeability At Intrusion Boundaries: New Results From Hydraulic Testing And Geophysical Logging In The Newark Rift Basin, New York, Usa, Jurg M. Matter, D. S. Goldberg, Roger H. Morin, M. Stute

United States Geological Survey: Staff Publications

Hydraulic tests and geophysical logging performed in the Palisades sill and the underlying sedimentary rocks in the NE part of the Newark Rift Basin, New York, USA, confirm that the particular transmissive zones are localized within the dolerite-sedimentary rock contact zone and within a narrow interval below this contact zone that is characterized by the occurrence of small layers of chilled dolerite. Transmissivity values determined from fluid injection, aquifer testing, and flowmeter measurements generally fall in the range of 8.1E-08 to 9.95E-06 m2/s and correspond to various scales of investigation. The analysis of acoustic and optical BHTV images …

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Sulfur Isotope Geochemistry Of Sulfide Minerals, Robert R. Seal Ii Jan 2006

Sulfur Isotope Geochemistry Of Sulfide Minerals, Robert R. Seal Ii

United States Geological Survey: Staff Publications

Sulfur, the 10th most abundant element in the universe and the 14th most abundant element in the Earth’s crust, is the defining element of sulfide minerals and provides insights into the origins of these minerals through its stable isotopes. The insights come from variations in the isotopic composition of sulfide minerals and related compounds such as sulfate minerals or aqueous sulfur species, caused by preferential partitioning of isotopes among sulfur-bearing phases, known as fractionation. These variations arise from differences in temperature, or more importantly, oxidation and reduction reactions acting upon the sulfur. The oxidation and reduction reactions can occur at …

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Alpersite (Mg,Cu)So4•7h2O, A New Mineral Of The Melanterite Group, And Cuprian Pentahydrite: Their Occurrence Within Mine Waste, Ronald C. Peterson, Jane M. Hammarstrom, Robert R. Seal Ii Jan 2006

Alpersite (Mg,Cu)So4•7h2O, A New Mineral Of The Melanterite Group, And Cuprian Pentahydrite: Their Occurrence Within Mine Waste, Ronald C. Peterson, Jane M. Hammarstrom, Robert R. Seal Ii

United States Geological Survey: Staff Publications

Alpersite, Mg0.58 Cu0.37 Zn0.02 Mn0.02 Fe0.01SO4 •7H2 O, a new mineral species with direct relevance to reactions in mine waste, occurs in a mineralogically zoned assemblage in sheltered areas at the abandoned Big Mike mine in central Nevada at a relative humidity of 65% and T = 4 °C. Blue alpersite, which is isostructural with melanterite (FeSO4 •7H2 O), is overlain by a light blue to white layer dominated by pickeringite, alunogen, and epsomite. X-ray diffraction data (MoKα radiation) from a single crystal of alpersite were refined in P21 …

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A Method For Mapping Corn Using The Us Geological Survey 1992 National Land Cover Dataset, S. K. Maxwell, J. R. Nuckols, M. H. Ward Jan 2006

A Method For Mapping Corn Using The Us Geological Survey 1992 National Land Cover Dataset, S. K. Maxwell, J. R. Nuckols, M. H. Ward

United States Geological Survey: Staff Publications

Long-term exposure to elevated nitrate levels in community drinking water supplies has been associated with an elevated risk of several cancers including non-Hodgkin’s lymphoma, colon cancer, and bladder cancer. To estimate human exposure to nitrate, specific crop type information is needed as fertilizer application rates vary widely by crop type. Corn requires the highest application of nitrogen fertilizer of crops grown in the Midwest US.We developed a method to refine the US Geological Survey National Land Cover Dataset (NLCD) (including map and original Landsat images) to distinguish corn from other crops. Overall average agreement between the resulting corn and other …

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Renewing The Conservation Commitment, Frank W. Davis, Dale D. Goble, J. Michael Scott Jan 2006

Renewing The Conservation Commitment, Frank W. Davis, Dale D. Goble, J. Michael Scott

United States Geological Survey: Staff Publications

As we write this in early 2005 there are several ESA-related pieces of legislation pending before Congress. Most of the proposed legislation is championed by Republican leaders from western states, who promise to strengthen the use of science or ensure fairer treatment of private landowners. Ir has become a perennial drama on the American political stage: "conservatives" rally to rein in a law that they believe has reached too far and "conservationists" mobilize ro defend the law that they believe offers the best ho pe for protecting biodiversity from relentless economic exploitation. There is much posturing, finger pointing, and, ultimately, …

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Breeding Biology And Success Of A Reintroduced Population Of The Critically Endangered Puaiohi (Myadestes Palmeri), Erik J. Tweed, Jeffrey T. Foster, Bethany L. Woodworth, William B. Monahan, Jherime L. Kellerman, Alan Lieberman Jan 2006

Breeding Biology And Success Of A Reintroduced Population Of The Critically Endangered Puaiohi (Myadestes Palmeri), Erik J. Tweed, Jeffrey T. Foster, Bethany L. Woodworth, William B. Monahan, Jherime L. Kellerman, Alan Lieberman

United States Geological Survey: Staff Publications

The ultimate success of reintroduction programs for endangered species depends on the ability of reintroduced animals to breed in the wild. We studied the nesting success and breeding biology of a reintroduced population of Puaiohi (Myadestes palmeri) on the island of Kaua‛i, Hawaii. Thirty-four captive-bred Puaiohi were released into the Alaka‛i Swamp in 1999–2001 and monitored using radiotelemetry. Ten females and two males paired with wild and other released birds, including one polygynous trio. From March to September, 31 nests were built. Mean clutch size was 2.0 eggs, daily nest survival was 0.97 ± 0.01 (mean ± SE) …

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Distribution Of Boreal Toad Populations In Relation To Estimated Uv-B Dose In Glacier National Park, Montana, Usa, Blake R. Hossack, Stephen A. Diamond, Paul Stephen Corn Jan 2006

Distribution Of Boreal Toad Populations In Relation To Estimated Uv-B Dose In Glacier National Park, Montana, Usa, Blake R. Hossack, Stephen A. Diamond, Paul Stephen Corn

United States Geological Survey: Staff Publications

A recent increase in ultraviolet B radiation is one hypothesis advanced to explain suspected or documented declines of the boreal toad (Bufo boreas Baird and Girard, 1852) across much of the western USA, where some experiments have shown ambient UV-B can reduce embryo survival. We examined B. boreas occupancy relative to daily UV-B dose at 172 potential breeding sites in Glacier National Park, Montana, to assess whether UV-B limits the distribution of toads. Dose estimates were based on ground-level UV-B data and the effects of elevation, local topographic and vegetative features, and attenuation in the water column. We also …

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