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2005

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Articles 211 - 240 of 417

Full-Text Articles in Earth Sciences

Seepage Study Of Mcleod Creek And East Canyon Creek Near Park City, Summit County, Utah, 2004, C. D. Wilkowske, U.S. Geological Survey, Snyderville Basin Water Reclamation District, U.S. Department Of The Interior Jan 2005

Seepage Study Of Mcleod Creek And East Canyon Creek Near Park City, Summit County, Utah, 2004, C. D. Wilkowske, U.S. Geological Survey, Snyderville Basin Water Reclamation District, U.S. Department Of The Interior

All U.S. Government Documents (Utah Regional Depository)

Seepage investigations on McLeod Creek downstream of U.S. Geological Survey streamflow-gaging station McLeod Creek near Park City, Utah, and its confluence with Kimball Creek during the summer of 2004 indicate that this section of the creek is a gaining reach. The total seepage gains ranged from 1.8 to 2.7 cubic feet per second, or a 32 to 55 percent gain. The apparent average total seepage gain was 2.2 cubic feet per second, or an average 42 percent gain. Seepage investigations from the U.S. Geological Survey streamflow-gaging station at East Canyon Creek below I-80 Rest Stop near Park City, Utah, to …

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Drought Preparedness Planning: Building Institutional Capacity, Donald A. Wilhite, Michael Hayes, Cody L. Knutson Jan 2005

Drought Preparedness Planning: Building Institutional Capacity, Donald A. Wilhite, Michael Hayes, Cody L. Knutson

National Drought Mitigation Center: Faculty Publications

Past attempts to manage drought and its impacts through a reactive, crisis management approach have been ineffective, poorly coordinated, and untimely, as illustrated by the hydro- illogical cycle in Figure 1. The crisis management approach has been followed in both developed and developing countries. Because of the ineffectiveness of this approach, greater interest has evolved in recent years in the adoption of a more proactive risk-based management approach in some countries (see Chapter 6). Other countries are striving to obtain a higher level of preparedness through development of national action programs that are part of the United Nations Convention to …

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A New Approach For Predicting Drought-Related Vegetation Stress: Integrating Satellite, Climate, And Biophysical Data Over The U.S. Central Plains, Tsegaue Tadesse, Jesslyn F. Brown, Michael Hayes Jan 2005

A New Approach For Predicting Drought-Related Vegetation Stress: Integrating Satellite, Climate, And Biophysical Data Over The U.S. Central Plains, Tsegaue Tadesse, Jesslyn F. Brown, Michael Hayes

National Drought Mitigation Center: Faculty Publications

Droughts are normal climate episodes, yet they are among the most expensive natural disasters in the world. Knowledge about the timing, severity, and pattern of droughts on the landscape can be incorporated into effective planning and decisionmaking. In this study, we present a data mining approach to modeling vegetation stress due to drought and mapping its spatial extent during the growing season. Rule-based regression tree models were generated that identify relationships between satellite-derived vegetation conditions, climatic drought indices, and biophysical data, including land-cover type, available soil water capacity, percent of irrigated farm land, and ecological type. The data mining method …

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Groundwater Study Of The Boddington Townsite, Gregory Paul Raper Jan 2005

Groundwater Study Of The Boddington Townsite, Gregory Paul Raper

Resource management technical reports

A study of the groundwater beneath the Boddington townsite was carried out in April 2002. The aim was to assess the salinity risk to the townsite infrastructure and to accelerate the implementation of effective salinity management for the town. The study consisted of field reconnaissance, a drilling program, expansion of a groundwater-monitoring network installed in March 2001, and groundwater monitoring.

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Agricultural Resource Priorities And Recommendations For The Avon River Basin Natural Resource Management Strategy, Paul D. Galloway, C E. Mcconnell, D W. Cummins, K Ohlsen Jan 2005

Agricultural Resource Priorities And Recommendations For The Avon River Basin Natural Resource Management Strategy, Paul D. Galloway, C E. Mcconnell, D W. Cummins, K Ohlsen

Resource management technical reports

This report for the Avon Natural Resource Management Strategy provides an assessment of the current status of land resources throughout the Avon River Basin in Western Australia. It identifies the sub-regions and landscape components of the area and the land resource assets. The greatest threats are salinity, soil acidification, subsurface compaction, waterlogging, water and wind erosion, and biosecurity.

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Gibson Oil Mallee Study : Drill Completion And Preliminary Hydrogeological Interpretation Report, John Andrew Simons, Peter Taylor, D L. Bennett, Western Australia. Department Of Conservation And Land Management Jan 2005

Gibson Oil Mallee Study : Drill Completion And Preliminary Hydrogeological Interpretation Report, John Andrew Simons, Peter Taylor, D L. Bennett, Western Australia. Department Of Conservation And Land Management

Resource management technical reports

Oil mallees are being planted in Western Australian wheatbelt farms with the expectation that they will reduce land salination by lowering watertables as well as providing income from combinations of eucalyptus oil distillation, power generation, activated carbon production and carbon sequestration in the future.

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Greenough Region Catchment Appraisal, Angela Stuart-Street, M Clarke Jan 2005

Greenough Region Catchment Appraisal, Angela Stuart-Street, M Clarke

Resource management technical reports

This report discusses a range of options for the Greenough region, which is comprised of eight shires including the Shires of Northampton, Chapman Valley, Mullewa, Greenough, Morawa, Irwin, Mingenew and Three Springs, and also the city of Geraldton. A range of options for reducing land degradation is discussed. Factors such as soil type, annual rainfall, enterprise mix and financial structure are also considered.

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Assessing Sandhill Crane Roosting Habitat Along The Platte River, Nebraska, P.J. Kinzel, J.M. Nelson, R.S. Parker Jan 2005

Assessing Sandhill Crane Roosting Habitat Along The Platte River, Nebraska, P.J. Kinzel, J.M. Nelson, R.S. Parker

United States Geological Survey: Publications

Each spring approximately 500,000 sandhill cranes and some endangered whooping cranes use the Central Platte River Valley in Nebraska as a staging habitat during their migration north to breeding and nesting grounds in Canada, Alaska, and the Siberian Arctic. Over the last century changes in the flow of the river have altered the river channels and the distribution of roost sites. USGS researchers studied linkages between water flow, sediment supply, channel morphology, and preferred sites for crane roosting. These results are useful for estimating crane populations and for providing resource managers with techniques to understand crane habitats.

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New Developments In The Remote Estimation Of The Fraction Of Absorbed Photosynthetically Active Radiation In Crops, Andrés Viña, Anatoly A. Gitelson Jan 2005

New Developments In The Remote Estimation Of The Fraction Of Absorbed Photosynthetically Active Radiation In Crops, Andrés Viña, Anatoly A. Gitelson

Center for Advanced Land Management Information Technologies: Publications

The fraction of absorbed photosynthetically active radiation, fAPAR, is an important biophysical characteristic in models of gas exchange between the terrestrial boundary layer and the atmosphere, as well as in the analysis of vegetation productivity. Synoptic estimation of fAPAR has been performed by using NDVI as a linear proxy of fAPAR, despite the saturation of NDVI at fAPAR beyond 0.7. This paper analyzes the NDVI/fAPAR relationship in row crops (i.e. maize and soybean), and evaluates alternative vegetation indices to overcome the loss of sensitivity of NDVI at moderate-to-high vegetation biomass. Red-edge NDVI, which uses NIR and a band around 700 …

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Contaminant Concentrations And Biomarker Responses Of Fish From The Mobile, Apalachicola, Savannah, And Pee Dee River Basins, Jo Ellen Hinck, V. S. Blazer, N. D. Denslow, T. S. Gross, T. W. May, C. E. Orazio, J. J. Coyle, P. J. Anderson, D. E. Tillitt Jan 2005

Contaminant Concentrations And Biomarker Responses Of Fish From The Mobile, Apalachicola, Savannah, And Pee Dee River Basins, Jo Ellen Hinck, V. S. Blazer, N. D. Denslow, T. S. Gross, T. W. May, C. E. Orazio, J. J. Coyle, P. J. Anderson, D. E. Tillitt

United States Geological Survey: Publications

No abstract provided.

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The Conservation Reserve Enhancement Program, Arthur W. Allen Jan 2005

The Conservation Reserve Enhancement Program, Arthur W. Allen

United States Geological Survey: Staff Publications

The Conservation Reserve Enhancement Program (CREP) reflects advancement in U.S. Department of Agriculture agricultural policy by addressing agriculturally related conservation on a multi-farm, landscape scale and establishing funding support and partnerships with state and non-governmental organizations. Underway in 25 states, with more being planned, the CREP addresses environmental issues on the farmed landscape with implications for environmental quality potentially reaching thousands of miles away from where program conservation practices are established. Most CREPs have been initiated only within the last 4 years. Monitoring programs to evaluate CREP performance have been established, but because of time needed to establish vegetative covers, …

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Major And Trace Element Composition Of Copiapite-Group Minerals And Coexisting Water From The Richmond Mine, Iron Mountain, California, Heather E. Jamieson, Clare Robinson, Charles N. Alpers, R. Blaine Mccleskey, D. Kirk Nordstrom, Ronald C. Peterson Jan 2005

Major And Trace Element Composition Of Copiapite-Group Minerals And Coexisting Water From The Richmond Mine, Iron Mountain, California, Heather E. Jamieson, Clare Robinson, Charles N. Alpers, R. Blaine Mccleskey, D. Kirk Nordstrom, Ronald C. Peterson

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

Copiapite-group minerals of the general formula AR4(SO4)6(OH)2• nH2O, where A is predominantly Mg, Fe2+, or 0.67Al3+, R is predominantly Fe3+, and n is typically 20, are among several secondary hydrous Fe sulfates occurring in the inactive mine workings of the massive sulfide deposit at Iron Mountain, CA, a USEPA Superfund site that produces extremely acidic drainage. Samples of copiapite-group minerals, some with coexisting water, were collected from the Richmond mine. Approximately 200 mL of brownish pore water with a pH of ‒0.9 were …

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Evaluation Of Argon Ages And Integrity Of Fluid-Inclusion Compositions: Stepwise Noble Gas Heating Experiments On 1.87 Ga Alunite From Tapajo´ S Province, Brazil, G.P. Landis, L.W. Snee, C. Juliani Jan 2005

Evaluation Of Argon Ages And Integrity Of Fluid-Inclusion Compositions: Stepwise Noble Gas Heating Experiments On 1.87 Ga Alunite From Tapajo´ S Province, Brazil, G.P. Landis, L.W. Snee, C. Juliani

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

Quantitative analyses are reported for active (N2, CH4, CO, CO2, H2, O2, HF, HCl, H2S, SO2) and noble (He, Ar, Ne) gases released by crushing and step heating of magmatic-hydrothermal alunite from the Tapajo´ s gold province in Brazil. This is the oldest known alunite (40Ar/39Ar age of 1.87 Ga), and because it has undergone minimal postdepositional thermal or tectonic strain, it is excellent material to test the retention of gas species in fluid inclusions and within the crystal structure over geological …

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Alunite And The Role Of Magmatic Fluids In The Tambo High-Sulfidation Deposit, El Indio–Pascua Belt, Chile, C.L. Deyell, R.O. Rye, G.P. Landis, T. Bissig Jan 2005

Alunite And The Role Of Magmatic Fluids In The Tambo High-Sulfidation Deposit, El Indio–Pascua Belt, Chile, C.L. Deyell, R.O. Rye, G.P. Landis, T. Bissig

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

The Tambo high-sulfidation deposit, located within the El Indio–Pascua belt in Chile, produced almost 25 t (0.8 M oz) of gold from altered Tertiary rhyodacitic volcanic rocks. Episodic magmatic-hydrothermal activity in the district occurred over at least 4 my and is characterized by several stages of acid-sulfate alteration, including magmatic-hydrothermal, magmatic steam, steam-heated, and apparent supergene assemblages. Two stages of Au±Ag mineralization are recognized and are hosted in barite and alunite within hydrothermal breccias and veins. Isotopic compositions of fluid in alunite show a dominant magmatic signature, with only a variable 18O-enriched meteoric water component throughout the entire hydrothermal …

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Secondary Sulfate Minerals Associated With Acid Drainage In The Eastern Us: Recycling Of Metals And Acidity In Surficial Environments, J. M. Hammarstrom, R. R. Seal Ii, A. L. Meier, J. M. Kornfeld Jan 2005

Secondary Sulfate Minerals Associated With Acid Drainage In The Eastern Us: Recycling Of Metals And Acidity In Surficial Environments, J. M. Hammarstrom, R. R. Seal Ii, A. L. Meier, J. M. Kornfeld

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

Weathering of metal-sulfide minerals produces suites of variably soluble efflorescent sulfate salts at a number of localities in the eastern United States. The salts, which are present on mine wastes, tailings piles, and outcrops, include minerals that incorporate heavy metals in solid solution, primarily the highly soluble members of the melanterite, rozenite, epsomite, halotrichite, and copiapite groups. The minerals were identified by a combination of powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and electron-microprobe. Base-metal salts are rare at these localities, and Cu, Zn, and Co are commonly sequestered as solid solutions within Fe- and Fe–Al sulfate minerals. Salt …

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Characterization Of Gas Chemistry And Noble-Gas Isotope Ratios Of Inclusion Fluids In Magmatic-Hydrothermal And Magmatic-Steam Alunite, Robert O. Rye, G.P. Landis Jan 2005

Characterization Of Gas Chemistry And Noble-Gas Isotope Ratios Of Inclusion Fluids In Magmatic-Hydrothermal And Magmatic-Steam Alunite, Robert O. Rye, G.P. Landis

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

Chemical and isotope data were obtained for the active gas and noble gas of inclusion fluids in coarse-grained samples of magmatic-hydrothermal and magmatic-steam alunite from well-studied deposits (Marysvale, Utah; Tambo, Chile; Tapajo´s, Brazil; Cactus, California; Pierina, Peru), most of which are discussed in this Volume. Primary fluid inclusions in the alunite typically are less than 0.2 µm but range up to several micrometers. Analyses of the active-gas composition of these alunitehosted inclusion fluids released in vacuo by both crushing and heating indicate consistent differences in the compositions of magmatic-hydrothermal and magmatic-steam fluids. The compositions of fluids released by crushing were …

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Evolution Of The Magmatic-Hydrothermal Acid-Sulfate System At Summitville, Colorado: Integration Of Geological, Stable-Isotope, And Fluid-Inclusion Evidence, Philip M. Bethke, Robert O. Rye, Roger E. Stoffregen, Peter G. Vikre Jan 2005

Evolution Of The Magmatic-Hydrothermal Acid-Sulfate System At Summitville, Colorado: Integration Of Geological, Stable-Isotope, And Fluid-Inclusion Evidence, Philip M. Bethke, Robert O. Rye, Roger E. Stoffregen, Peter G. Vikre

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

The Summitville Au–Ag–Cu deposit is a classic volcanic dome-hosted high-sulfidation deposit. It occurs in the Quartz Latite of South Mountain, a composite volcanic dome that was emplaced along the coincident margins of the Platoro and Summitville calderas at 22.5±0.5 Ma, penecontemporaneous with alteration and mineralization. A penecontemporaneous quartz monzonite porphyry intrusion underlies the district and is cut and overlain by pyrite–quartz stockwork veins with traces of chalcopyrite and molybdenite. Alteration and mineralization proceeded through three hypogene stages and a supergene stage, punctuated by at least three periods of hydrothermal brecciation. Intense acid leaching along fractures in the quartz latite produced …

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Paleoproterozoic High-Sulfidation Mineralization In The Tapajo´S Gold Province, Amazonian Craton, Brazil: Geology, Mineralogy, Alunite Argon Age, And Stable-Isotope Constraints, Caetano Juliani, Robert O. Rye, Carmen M.D. Nunes, Lawrence W. Snee, Rafael H. Corrêa Silva, Lena V.S. Monteiro, Jorge S. Bettencourt, Rainer Neumann, Arnaldo Alcover Neto Jan 2005

Paleoproterozoic High-Sulfidation Mineralization In The Tapajo´S Gold Province, Amazonian Craton, Brazil: Geology, Mineralogy, Alunite Argon Age, And Stable-Isotope Constraints, Caetano Juliani, Robert O. Rye, Carmen M.D. Nunes, Lawrence W. Snee, Rafael H. Corrêa Silva, Lena V.S. Monteiro, Jorge S. Bettencourt, Rainer Neumann, Arnaldo Alcover Neto

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

The Brazilian Tapajós gold province contains the first evidence of high-sulfidation gold mineralization in the Amazonian Craton. The mineralization appears to be in large nested calderas. The Tapajós–Parima (or Ventuari–Tapajo´ s) geological province consists of a metamorphic, igneous, and sedimentary sequence formed during a 2.10 to 1.87 Ga ocean ̶ continent orogeny. The high-sulfidation mineralization with magmatic-hydrothermal alunite is related to hydrothermal breccias hosted in a rhyolitic volcanic ring complex that contains granitic stocks ranging in age from 1.89 to 1.87 Ga. Cone-shaped hydrothermal breccias, which flare upward, contain vuggy silica and have an overlying brecciated cap of massive silica; …

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A Review Of The Stable-Isotope Geochemistry Of Sulfate Minerals In Selected Igneous Environments And Related Hydrothermal Systems, Robert O. Rye Jan 2005

A Review Of The Stable-Isotope Geochemistry Of Sulfate Minerals In Selected Igneous Environments And Related Hydrothermal Systems, Robert O. Rye

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

The stable-isotope geochemistry of sulfate minerals that form principally in I-type igneous rocks and in the various related hydrothermal systems that develop from their magmas and evolved fluids is reviewed with respect to the degree of approach to isotope equilibrium between minerals and their parental aqueous species. Examples illustrate classical stable-isotope systematics and principles of interpretation in terms of fundamental processes that occur in these systems to produce (1) sulfate in igneous apatite, (2) igneous anhydrite, (3) anhydrite in porphyry-type deposits, (4) magmatic-hydrothermal alunite and closely related barites in high-sulfidation mineral deposits, (5) coarse-banded alunite in magmatic-steam systems, (6) …

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"Sour Gas" Hydrothermal Jarosite: Ancient To Modern Acid-Sulfate Mineralization In The Southern Rio Grande Rift, Virgil W. Lueth, Robert O. Rye, Lisa Peters Jan 2005

"Sour Gas" Hydrothermal Jarosite: Ancient To Modern Acid-Sulfate Mineralization In The Southern Rio Grande Rift, Virgil W. Lueth, Robert O. Rye, Lisa Peters

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

As many as 29 mining districts along the Rio Grande Rift in southern New Mexico contain Rio Grande Rift-type (RGR) deposits consisting of fluorite–barite±sulfide–jarosite, and additional RGR deposits occur to the south in the Basin and Range province near Chihuahua, Mexico. Jarosite occurs in many of these deposits as a late-stage hydrothermal mineral coprecipitated with fluorite, or in veinlets that crosscut barite. In these deposits, many of which are limestone-hosted, jarosite is followed by natrojarosite and is nested within silicified or argillized wallrock and a sequence of fluorite–bariteFsulfide and late hematite– gypsum. These deposits range in age from ~10 to …

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Stable-Isotope Geochemistry Of The Pierina High-Sulfidation Au–Ag Deposit, Peru: Influence Of Hydrodynamics On So42-–H2S Sulfur Isotopic Exchange In Magmatic-Steam And Steam-Heated Environments, Richard H. Fifarek, Robert O. Rye Jan 2005

Stable-Isotope Geochemistry Of The Pierina High-Sulfidation Au–Ag Deposit, Peru: Influence Of Hydrodynamics On So42-–H2S Sulfur Isotopic Exchange In Magmatic-Steam And Steam-Heated Environments, Richard H. Fifarek, Robert O. Rye

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

The Pierina high-sulfidation Au–Ag deposit formed 14.5 my ago in rhyolite ash flow tuffs that overlie porphyritic andesite and dacite lavas and are adjacent to a crosscutting and interfingering dacite flow dome complex. The distribution of alteration zones indicates that fluid flow in the lavas was largely confined to structures but was dispersed laterally in the tuffs because of a high primary and alteration-induced permeability. The lithologically controlled hydrodynamics created unusual fluid, temperature, and pH conditions that led to complete SO4 2‒–H2S isotopic equilibration during the formation of some magmatic-steam and steam-heated alunite, a phenomenon not …

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Supergene Destruction Of A Hydrothermal Replacement Alunite Deposit At Big Rock Candy Mountain, Utah: Mineralogy, Spectroscopic Remote Sensing, Stable-Isotope, And Argon-Age Evidences, Charles G. Cunningham, Robert O. Rye, Barnaby W. Rockwell, Michael J. Kunk, Terry B. Councell Jan 2005

Supergene Destruction Of A Hydrothermal Replacement Alunite Deposit At Big Rock Candy Mountain, Utah: Mineralogy, Spectroscopic Remote Sensing, Stable-Isotope, And Argon-Age Evidences, Charles G. Cunningham, Robert O. Rye, Barnaby W. Rockwell, Michael J. Kunk, Terry B. Councell

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

Big Rock Candy Mountain is a prominent center of variegated altered volcanic rocks in west-central Utah. It consists of the eroded remnants of a hypogene alunite deposit that, at ~21 Ma, replaced intermediate-composition lava flows. The alunite formed in steam-heated conditions above the upwelling limb of a convection cell that was one of at least six spaced at 3- to 4- km intervals around the margin of a monzonite stock. Big Rock Candy Mountain is horizontally zoned outward from an alunite core to respective kaolinite, dickite, and propylite envelopes. The altered rocks are also vertically zoned from a lower pyrite– …

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Chemical Openness And Potential For Misinterpretation Of The Solute Environment Of Coastal Sabkhat, Warren W. Wood, Ward E. Sanford, Shaun K. Frape Jan 2005

Chemical Openness And Potential For Misinterpretation Of The Solute Environment Of Coastal Sabkhat, Warren W. Wood, Ward E. Sanford, Shaun K. Frape

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

Sabkha deposits in the geologic record are commonly used to interpret the environmental conditions of deposition. Implicit in this use is the assumption that the solute system is chemically closed, that is, the authigenic minerals represent the composition of the fluids in their environment of origin. Thermodynamic and mass-balance calculations based on measurements of water and solute flux of contemporary Abu Dhabi coastal sabkha system, however, demonstrate that the system is open for sodium and chloride, where nearly half of the input is lost, but closed for sulfur, where nearly 100% is retained. Sulfur and chloride isotopes were consistent with …

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Temporal Analysis Of The Frequency And Duration Of Low And High Streamflow: Years Of Record Needed To Characterize Streamflow Variability, Seungho Huh, David A. Dickey, M. R. Meador, K. E. Ruhl Jan 2005

Temporal Analysis Of The Frequency And Duration Of Low And High Streamflow: Years Of Record Needed To Characterize Streamflow Variability, Seungho Huh, David A. Dickey, M. R. Meador, K. E. Ruhl

United States Geological Survey: Staff Publications

A temporal analysis of the number and duration of exceedences of high- and low-flow thresholds was conducted to determine the number of years required to detect a level shift using data from Virginia, North Carolina, and South Carolina. Two methods were used—ordinary least squares assuming a known error variance and generalized least squares without a known error variance. Using ordinary least squares, the mean number of years required to detect a one standard deviation level shift in measures of low-flow variability was 57.2 (28.6 on either side of the break), compared to 40.0 years for measures of high-flow variability. These …

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The Composition Of Coexisting Jarosite-Group Minerals And Water From The Richmond Mine, Iron Mountain, California, Heather E. Jamieson, Clare Robinson, Charles N. Alpers, D. Kirk Nordstrom, Alexei Poustovetov, Heather A. Lowers Jan 2005

The Composition Of Coexisting Jarosite-Group Minerals And Water From The Richmond Mine, Iron Mountain, California, Heather E. Jamieson, Clare Robinson, Charles N. Alpers, D. Kirk Nordstrom, Alexei Poustovetov, Heather A. Lowers

United States Geological Survey: Staff Publications

Jarosite-group minerals accumulate in the form of stalactites and fine-grained mud on massive pyrite in the D drift of the Richmond mine, Iron Mountain, California. Water samples were collected by placing beakers under the dripping stalactites and by extracting pore water from the mud using a centrifuge. The water is rich in Fe3+ and SO42–, with a pH of approximately 2.1, which is significantly higher than the extremely acidic waters found elsewhere in the mine. Electron-microprobe analysis and X-ray mapping indicate that the small crystals (<10 > μm in diameter) are compositionally zoned with respect to Na …

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Taxonomic Relationships Among Phenacomys Voles As Inferred By Cytochrome B, M. Renee Bellinger, Susan M. Haig, Eric D. Forsman, Thomas D. Mullins Jan 2005

Taxonomic Relationships Among Phenacomys Voles As Inferred By Cytochrome B, M. Renee Bellinger, Susan M. Haig, Eric D. Forsman, Thomas D. Mullins

United States Geological Survey: Staff Publications

Taxonomic relationships among red tree voles (Phenacomys longicaudus longicaudus, P. l. silvicola), the Sonoma tree vole (P. pomo), the white-footed vole (P. albipes), and the heather vole (P. intermedius) were examined using 664 base pairs of the mitochondrial cytochrome b gene. Results indicate specific differences among red tree voles, Sonoma tree voles, white-footed voles, and heather voles, but no clear difference between the 2 Oregon subspecies of red tree voles (P. l. longicaudus and P. l. silvicola). Our data further indicated a close relationship between tree voles and albipes, …

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Comparison Of Individual And Pooled Sampling Methods For Detecting Bacterial Pathogens Of Fish, Sonia Mumford, Chris Patterson, Joy Evered, Ray Brunson, Jay Levine, Jim Winton Jan 2005

Comparison Of Individual And Pooled Sampling Methods For Detecting Bacterial Pathogens Of Fish, Sonia Mumford, Chris Patterson, Joy Evered, Ray Brunson, Jay Levine, Jim Winton

United States Geological Survey: Staff Publications

Examination of finfish populations for viral and bacterial pathogens is an important component of fish disease control programs worldwide. Two methods are commonly used for collecting tissue samples for bacteriological culture, the currently accepted standards for detection of bacterial fish pathogens. The method specified in the Office International des Epizooties Manual of Diagnostic Tests for Aquatic Animals permits combining renal and splenic tissues from as many as 5 fish into pooled samples. The American Fisheries Society (AFS) Blue Book/US Fish and Wildlife Service (USFWS) Inspection Manual specifies the use of a bacteriological loop for collecting samples from the kidney of …

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Characterization Of Waste Rock Associated With Acid Drainage At The Penn Mine, California, By Ground-Based Visible To Short-Wave Infrared Reflectance Spectroscopy Assisted By Digital Mapping, Irene C. Montero S., George H. Brimhalla, Charles N. Alpers, Gregg A. Swayze Jan 2005

Characterization Of Waste Rock Associated With Acid Drainage At The Penn Mine, California, By Ground-Based Visible To Short-Wave Infrared Reflectance Spectroscopy Assisted By Digital Mapping, Irene C. Montero S., George H. Brimhalla, Charles N. Alpers, Gregg A. Swayze

United States Geological Survey: Staff Publications

Prior to remediation at the abandoned Cu–Zn Penn Mine in the Foothills massive sulfide belt of the Sierra Nevada, CA, acid mine drainage (AMD) was created, in part, by the subaerial oxidation of sulfides exposed on several waste piles. To support remediation efforts, a mineralogical study of the waste piles was undertaken by acquiring reflectance spectra (measured in the visible to short-wave infrared range of light (0.35–2.5 μm) using a portable, digitally integrated pen tablet PC mapping system with differential global positioning system and laser rangefinder support. Analysis of the spectral data made use of a continuum removal and band-shape …

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Perennial Grasses - Are They For Me? Workshop Development Guide For Facilitators, Trevor Lacey Jan 2005

Perennial Grasses - Are They For Me? Workshop Development Guide For Facilitators, Trevor Lacey

Agriculture reports

Farmers will be able to recognise landscape components on their farm that are at risk of salinity (current, imminent or future) and be aware of a range of available options available to them in managing this risk.

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Tylosaurus Kansasensis, A New Species Of Tylosaurine (Squamata, Mosasauridae) From The Niobrara Chalk Of Western Kansas, Usa, M. J. Everhart Jan 2005

Tylosaurus Kansasensis, A New Species Of Tylosaurine (Squamata, Mosasauridae) From The Niobrara Chalk Of Western Kansas, Usa, M. J. Everhart

Sternberg Museum of Natural History Faculty Publications

Tylosaurus kansasensis sp. nov. is described herein on the basis of thirteen specimens collected from the Smoky Hill Chalk (upper Coniacian) of western Kansas, USA. The new species, originally designated Tylosaurus n. sp., co-occurred with T. nepaeolicus and exhibits a number of primitive characters that place it in a basal position in the mosasaur phylogeny. Among the key differences separating this species from other tylosaurines are a shortened, more rounded pre-dental process of the premaxilla, a distinctive quadrate lacking an infrastapedial process, and a parietal foramen located adjacent to the frontal-parietal suture.

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