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Sample records for great basin states

  1. Glaciation in the Great Basin of the Western United States

    NASA Astrophysics Data System (ADS)

    Osborn, Gerald; Bevis, Ken

    2001-07-01

    Forty individually named ranges, plateaus, and massifs draining wholly or partly into the Great Basin of the western United States show definite evidence of Pleistocene glaciation. The most obvious deposits are a family of moraines designated, among other names, "Tioga", "Angel Lake", and "Pinedale". Such moraines generally can be traced from range to range away from described type moraines. These deposits have been numerically assigned to Late Wisconsinan glaciation in the Wasatch Range, White Mountains, Boulder Mountain, and Sierra Nevada on the basis of radiocarbon and surface-exposure ages, and have been assigned to Late Wisconsinan time in several other ranges on the basis of relative-age studies. The type Angel Lake moraine, and most other equivalent moraines across the Great Basin, are thick, hummocky, lobate piles of till rather than looping ridges. The thicknesses of the moraines (often 60+m) can be explained by heavy debris loads, and/or glacial advance, retreat, and readvance to the same positions a number of times, which is consistent with recent evidence that multiple Late Wisconsinan advances, possibly related to Heinrich and Dansgaard-Oeschger events, occurred in the Sierra Nevada. Pre-Angel Lake deposits occur in many Great Basin ranges, but it is currently difficult or perhaps impossible to determine if these deposits are equivalent to each other and what their relationship is to pre-Tioga deposits in the Sierra Nevada. Numerical ages are rare and relative-age studies suggest that pre-Angel Lake deposits may be products of more than one glaciation. Mapped pre-Angel Lake glaciers were longer than their Angel Lake counterparts, but the length differences do not translate into large differences in ELA depression. There is evidence of two minor latest Pleistocene or early Holocene advances in some ranges, judging from the presence of overlying Mazama tephra and/or weathering comparisons to local Angel Lake moraines. In the latter part of the Holocene

  2. 76 FR 17347 - Revision to the California State Implementation Plan, Great Basin Unified Air Pollution Control...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-29

    ...) * * * (D) Great Basin Unified Air Pollution Control District (1) Rule 201, ``Exemptions,'' adopted on... AGENCY 40 CFR Part 52 Revision to the California State Implementation Plan, Great Basin Unified Air Pollution Control District CFR Correction In Title 40 of the Code of Federal Regulations, Part 52 (Sec....

  3. Hydrogeologic framework of the Great Basin region of Nevada, Utah, and adjacent states

    USGS Publications Warehouse

    Plume, R.W.

    1996-01-01

    Regional aquifer systems in the Great Basin consist of carbonate-rock aquifers in the eastern Great Basin and basin-fill aquifers throughout the region. In the carbonate-rock aquifers, barriers to regional flow include Precambrian crystalline basement, upper Precambrian and Lower Cambrian clastic sedimentary rocks, and Jurassic to Tertiary granitic rocks. Basin-fill aquifers are connected to carbonate-rock aquifers in the eastern Great Basin and can be hydraulically connected with each other throughout the Great Basin.

  4. Microbiology and geochemistry of great boiling and mud hot springs in the United States Great Basin.

    PubMed

    Costa, Kyle C; Navarro, Jason B; Shock, Everett L; Zhang, Chuanlun L; Soukup, Debbie; Hedlund, Brian P

    2009-05-01

    A coordinated study of water chemistry, sediment mineralogy, and sediment microbial community was conducted on four >73 degrees C springs in the northwestern Great Basin. Despite generally similar chemistry and mineralogy, springs with short residence time (approximately 5-20 min) were rich in reduced chemistry, whereas springs with long residence time (>1 day) accumulated oxygen and oxidized nitrogen species. The presence of oxygen suggested that aerobic metabolisms prevail in the water and surface sediment. However, Gibbs free energy calculations using empirical chemistry data suggested that several inorganic electron donors were similarly favorable. Analysis of 298 bacterial 16S rDNAs identified 36 species-level phylotypes, 14 of which failed to affiliate with cultivated phyla. Highly represented phylotypes included Thermus, Thermotoga, a member of candidate phylum OP1, and two deeply branching Chloroflexi. The 276 archaeal 16S rDNAs represented 28 phylotypes, most of which were Crenarchaeota unrelated to the Thermoprotei. The most abundant archaeal phylotype was closely related to "Candidatus Nitrosocaldus yellowstonii", suggesting a role for ammonia oxidation in primary production; however, few other phylotypes could be linked with energy calculations because phylotypes were either related to chemoorganotrophs or were unrelated to known organisms. PMID:19247786

  5. Great Basin paleontological database

    USGS Publications Warehouse

    Zhang, N.; Blodgett, R.B.; Hofstra, A.H.

    2008-01-01

    The U.S. Geological Survey has constructed a paleontological database for the Great Basin physiographic province that can be served over the World Wide Web for data entry, queries, displays, and retrievals. It is similar to the web-database solution that we constructed for Alaskan paleontological data (www.alaskafossil.org). The first phase of this effort was to compile a paleontological bibliography for Nevada and portions of adjacent states in the Great Basin that has recently been completed. In addition, we are also compiling paleontological reports (Known as E&R reports) of the U.S. Geological Survey, which are another extensive source of l,egacy data for this region. Initial population of the database benefited from a recently published conodont data set and is otherwise focused on Devonian and Mississippian localities because strata of this age host important sedimentary exhalative (sedex) Au, Zn, and barite resources and enormons Carlin-type An deposits. In addition, these strata are the most important petroleum source rocks in the region, and record the transition from extension to contraction associated with the Antler orogeny, the Alamo meteorite impact, and biotic crises associated with global oceanic anoxic events. The finished product will provide an invaluable tool for future geologic mapping, paleontological research, and mineral resource investigations in the Great Basin, making paleontological data acquired over nearly the past 150 yr readily available over the World Wide Web. A description of the structure of the database and the web interface developed for this effort are provided herein. This database is being used ws a model for a National Paleontological Database (which we am currently developing for the U.S. Geological Survey) as well as for other paleontological databases now being developed in other parts of the globe. ?? 2008 Geological Society of America.

  6. Transition of vegetation states positively affects harvester ants in the Great Basin, United States

    USGS Publications Warehouse

    Holbrook, Joseph D.; Pilliod, David; Arkle, Robert; Rachlow, Janet L.; Vierling, Kerri T.; Wiest, Michelle M.

    2016-01-01

    Invasions by non-native plants can alter ecosystems such that new ecological states are reached, but less is known about how these transitions influence animal populations. Sagebrush (Artemisia tridentata) ecosystems are experiencing state changes because of fire and invasion by exotic annual grasses. Our goal was to study the effects of these state changes on the Owyhee and western harvester ants (Pogonomyrmex salinusOlsen and P. occidentalis Cresson, respectively). We sampled 358 1-ha plots across the northern Great Basin, which captured unburned and burned conditions across 1 −≥31 years postfire. Our results indicated an immediate and consistent change in vegetation states from shrubland to grassland between 1 and 31 years postfire. Harvester ant occupancy was unrelated to time since fire, whereas we observed a positive effect of fire on nest density. Similarly, we discovered that fire and invasion by exotic annuals were weak predictors of harvester ant occupancy but strong predictors of nest density. Occupancy of harvester ants was more likely in areas with finer-textured soils, low precipitation, abundant native forbs, and low shrub cover. Nest density was higher in arid locations that recently burned and exhibited abundant exotic annual and perennial (exotic and native) grasses. Finally, we discovered that burned areas that received postfire restoration had minimal influence on harvester ant occupancy or nest density compared with burned and untreated areas. These results suggest that fire-induced state changes from native shrublands to grasslands dominated by non-native grasses have a positive effect on density of harvester ants (but not occupancy), and that postfire restoration does not appear to positively or negatively affect harvester ants. Although wildfire and invasion by exotic annual grasses may negatively affect other species, harvester ants may indeed be one of the few winners among a myriad of losers linked to vegetation state changes within

  7. Estimate of ground water in storage in the Great Lakes basin, United States, 2006

    USGS Publications Warehouse

    Coon, William F.; Sheets, Rodney A.

    2006-01-01

    Hydrogeologic data from Regional Aquifer System Analyses (RASA) studies by the U.S. Geological Survey in the Great Lakes Basin, United States, during 1978-95, were compiled and used to estimate the total volume of water that is stored in the many aquifers of the basin. These studies focused on six regional aquifer systems: the Cambrian-Ordovician aquifer system in Wisconsin, Illinois, and Indiana; the Silurian- Devonian aquifers in Wisconsin, Michigan, Illinois, Indiana, and Ohio; the surficial aquifer system (aquifers of alluvial and glacial origin) found throughout the Great Lakes Basin; and the Pennsylvanian sandstone and carbonate-rock aquifers and the Mississippian sandstone aquifer in Michigan. Except for the surficial aquifers, all of these aquifer systems are capable of yielding substantial quantities of water and are not small aquifers with only local importance. Individual surficial aquifers, although small in comparison to the bedrock aquifers, collectively represent large potential sources of ground water and therefore have been treated as a regional system. Summation of ground-water volumes in the many regional aquifers of the basin indicates that about 1,340 cubic miles of water is in storage; of this, about 984 cubic miles is considered freshwater (that is, water with dissolved-solids concentration less than 1,000 mg/L). These volumes should not be interpreted as available in their entirety to meet water-supply needs; complete dewatering of any aquifer is environmentally undesirable. The amount of water that is considered available on the basis of water quality and environmental, economic, and legal constraints has not been determined. The effect of heavy pumping in the Chicago, Ill., and Milwaukee, Wis., areas, which has caused the regional ground-water divide in the Cambrian-Ordovician aquifer system to shift westward, has been included in the above estimates. This shift in the ground-water divide has increased the amount of water in storage in the

  8. Great Basin Paleontological Bibliography

    USGS Publications Warehouse

    Blodgett, Robert B.; Zhang, Ning; Hofstra, Albert H.; Morrow, Jared R.

    2007-01-01

    Introduction This work was conceived as a derivative product for 'The Metallogeny of the Great Basin' project of the Mineral Resources Program of the U.S. Geological Survey. In the course of preparing a fossil database for the Great Basin that could be accessed from the Internet, it was determined that a comprehensive paleontological bibliography must first be compiled, something that had not previously been done. This bibliography includes published papers and abstracts as well as unpublished theses and dissertations on fossils and stratigraphy in Nevada and adjoining portions of California and Utah. This bibliography is broken into first-order headings by geologic age, secondary headings by taxonomic group, followed by ancillary topics of interest to both paleontologists and stratigraphers; paleoecology, stratigraphy, sedimentary petrology, paleogeography, tectonics, and petroleum potential. References were derived from usage of Georef, consultation with numerous paleontologists and geologists working in the Great Basin, and literature currently on hand with the authors. As this is a Web-accessible bibliography, we hope to periodically update it with new citations or older references that we have missed during this compilation. Hence, the authors would be grateful to receive notice of any new or old papers that the readers think should be added. As a final note, we gratefully acknowledge the helpful reviews provided by A. Elizabeth J. Crafford (Anchorage, Alaska) and William R. Page (USGS, Denver, Colorado).

  9. Pre-mesozoic palinspastic reconstruction of the eastern great basin (Western United States).

    PubMed

    Levy, M; Christie-Blick, N

    1989-09-29

    The Great Basin of the western United States has proven important for studies of Proterozoic and Paleozoic geology [2500 to 245 million years ago (Ma)] and has been central to the development of ideas about the mechanics of crustal shortening and extension. An understanding of the deformational history of this region during Mesozoic and Cenozoic time (245 Ma to the present) is required for palinspastic reconstruction of now isolated exposures of older geology in order to place these in an appropriate regional geographic context. Considerable advances in unraveling both the crustal shortening that took place during Mesozoic to early Cenozoic time (especially from about 150 to 50 Ma) and the extension of the past 37 million years have shown that earlier reconstructions need to be revised significantly. A new reconstruction is developed for rocks of middle Proterozoic to Early Cambrian age based on evidence that total shortening by generally east-vergent thrusts and folds was at least 104 to 135 kilometers and that the Great Basin as a whole accommodated approximately 250 kilometers of extension in the direction 287 degrees +/- 12 degrees between the Colorado Plateau and the Sierra Nevada. Extension is assumed to be equivalent at all latitudes because available paleomagnetic evidence suggests that the Sierra Nevada experienced little or no rotation with respect to the extension direction since the late Mesozoic. An estimate of the uncertainty in the amount of extension obtained from geological and paleomagnetic uncertainties increases northward from +/-56 kilometers at 36 degrees 30N to (-87)(+108) kilometers at 40 degrees N. On the basis of the reconstruction, the original width of the preserved part of the late Proterozoic and Early Cambrian basin was about 150 to 300 kilometers, about 60 percent of the present width, and the basin was oriented slightly more north-south with respect to present-day coordinates. PMID:17776796

  10. Pre-Mesozoic palinspastic reconstruction of the eastern Great Basin (western United States)

    SciTech Connect

    Levy, M.; Christie-Blick, N.

    1989-09-29

    The Great Basin of the western United States has proven important for studies of Proterozoic and Paleozoic geology and has been central to the development of ideas about the mechanics of crustal shortening and extension. An understanding of the deformational history of this region during Mesozoic and Cenozoic time is required for palinspastic reconstruction of now isolated exposures of older geology in order to place these in an appropriate regional geographic context. A new reconstruction is developed for rocks of middle Proterozoic to Early Cambrian age based on evidence that total shortening by generally east-vergent thrusts and folds was at least 104 to 135 kilometers and that the Great Basin as a whole accommodated {approximately}250 kilometers of extension in the direction 287{degree} {plus_minus} 12{degree} between the Colorado Plateau and the Sierra Nevada. Extension is assumed to be equivalent at all latitudes because available paleomagnetic evidence suggests that the Sierra Nevada experienced little or no rotation with respect to the extension direction since the late Mesozoic. An estimate of the uncertainty in the amount of extension obtained from geological and paleomagnetic uncertainties increases northward from {plus_minus}56 kilometers at 36{degree}30{prime}N to {sup +108}{sub {minus}87} kilometers at 40{degree}N. On the basis of the reconstruction, the original width of the preserved part of the late Proterozoic and Early Cambrian basin was about 150 to 300 kilometers, about 60 percent of the present width, and the basin was oriented slightly more north-south with respect to present-day coordinates.

  11. Biological science in the Great Basin

    USGS Publications Warehouse

    U.S. Geological Survey

    2005-01-01

    The Great Basin is an expanse of desert and high moun-tains situated between the Rocky Mountains and the Sierra Nevada of the western United States. The most explicit description of the Great Basin is that area in the West where surface waters drain inland. In other words, the Great Basin is comprised of many separate drainage areas - each with no outlet. What at first glance may appear as only a barren landscape, the Great Basin upon closer inspection reveals island mountains, sagebrush seas, and intermittent aquatic habitats, all teeming with an incredible number and variety of plants and animals. Biologists at the USGS are studying many different species and ecosystems in the Great Basin in order to provide information about this landscape for policy and land-management decision-making. The following stories represent a few of the many projects the USGS is conducting in the Great Basin.

  12. Middle Miocene hiatus in volcanic activity in the Great Basin area of the Western United States

    USGS Publications Warehouse

    McKee, E.H.; Noble, D.C.; Silberman, M.L.

    1970-01-01

    A summary of potassium-argon dates shows that a high level of igneous activity in the Great Basin and adjacent regions during middle Tertiary time (40 to 20 my ago) was followed by a period of relative quiescence in middle Miocene time that lasted for several million years (from 20 to 17 my ago). Volcanism resumed 16 my ago mainly at the margins of the region and has continued to the present. ?? 1970.

  13. Aquifer systems in the Great Basin region of Nevada, Utah, and adjacent states; a study plan

    USGS Publications Warehouse

    Harrill, James R.; Welch, A.H.; Prudic, D.E.; Thomas, J.M.; Carman, R.L.; Plume, R.W.; Gates, J.S.; Mason, J.L.

    1983-01-01

    The Great Basin Regional Aquifer Study includes about 140,000 square miles in parts of Nevada, Utah, California, Idaho, Oregon , and Arizona within which 240 hydrographic areas occupy structural depressions formed primarily by basin-and-range faulting. The principal aquifers are in basin-fill deposits; however, significant carbonate-rock aquifers underlie much of eastern Nevada and western Utah. In October 1980, the U.S. Geological Survey started a 4-year study to: (1) describe the ground-water systems, (2) analyze the changes that have led to the systems ' present conditions, (3) tie the results of this and previous studies together in a regional analysis, and (4) provide means by which effects of future ground-water development can be estimated. A plan of work is presented that describes the general approach to be taken. It defines the major tasks necessary to meet objectives and defines constraints on the scope of work. The approach has been influenced by the diverse nature of ground water flow systems and the large number of basins. A detailed appraisal of 240 individual areas would require more resources than are available. Consequently, the general approach is to study selected ' typical ' areas and key hydrologic processes. Effort during the first three years will be directed toward describing the regional hydrology, conducting detailed studies of ' type ' areas and studying selected hydrologic processes. Effort during the final year will be directed toward developing a regional analysis of results. Special studies will include evaluation of regional geochemistry , regional hydrogeology, recharge, ground-water discharge, and use of remote sensing. Areas to be studied using ground-water flow models include the regional carbonate-rock province in eastern Nevada and western Utah, six valleys--Las Vegas, Carson, Paradise, Dixie, Smith Creek, and Stagecoach--Nevada, plus Jordan Valley, the Millford area, and Tule Valley in Utah. The results will be presented in a

  14. Stable isotope composition of waters in the Great Basin, United States 1. Air-mass trajectories

    USGS Publications Warehouse

    Friedman, I.; Harris, J.M.; Smith, G.I.; Johnson, C.A.

    2002-01-01

    Isentropic trajectories, calculated using the NOAA/Climate Monitoring and Diagnostics Laboratory's isentropic transport model, were used to determine air-parcel origins and the influence of air mass trajectories on the isotopic composition of precipitation events that occurred between October 1991 and September 1993 at Cedar City, Utah, and Winnemucca, Nevada. Examination of trajectories that trace the position of air parcels backward in time for 10 days indicated five distinct regions of water vapor origin: (1) Gulf of Alaska and North Pacific, (2) central Pacific, (3) tropical Pacific, (4) Gulf of Mexico, and (5) continental land mass. Deuterium (??D) and oxygen-18 (??18O) analyses were made of precipitation representing 99% of all Cedar City events. Similar analyses were made on precipitation representing 66% of the precipitation falling at Winnemucca during the same period. The average isotopic composition of precipitation derived from each water vapor source was determined. More than half of the precipitation that fell at both sites during the study period originated in the tropical Pacific and traveled northeast to the Great Basin; only a small proportion traversed the Sierra Nevada. The isotopic composition of precipitation is determined by air-mass origin and its track to the collection station, mechanism of droplet formation, reequilibration within clouds, and evaporation during its passage from cloud to ground. The Rayleigh distillation model can explain the changes in isotopic composition of precipitation as an air mass is cooled pseudo-adiabatically during uplift. However, the complicated processes that take place in the rapidly convecting environment of cumulonimbus and other clouds that are common in the Great Basin, especially in summer, require modification of this model because raindrops that form in the lower portion of those clouds undergo isotopic change as they are elevated to upper levels of the clouds from where they eventually drop to the

  15. Stable isotope composition of waters in the Great Basin, United States 1. Air-mass trajectories

    NASA Astrophysics Data System (ADS)

    Friedman, Irving; Harris, Joyce M.; Smith, George I.; Johnson, Craig A.

    2002-10-01

    Isentropic trajectories, calculated using the NOAA/Climate Monitoring and Diagnostics Laboratory's isentropic transport model, were used to determine air-parcel origins and the influence of air mass trajectories on the isotopic composition of precipitation events that occurred between October 1991 and September 1993 at Cedar City, Utah, and Winnemucca, Nevada. Examination of trajectories that trace the position of air parcels backward in time for 10 days indicated five distinct regions of water vapor origin: (1) Gulf of Alaska and North Pacific, (2) central Pacific, (3) tropical Pacific, (4) Gulf of Mexico, and (5) continental land mass. Deuterium (δD) and oxygen-18 (δ18O) analyses were made of precipitation representing 99% of all Cedar City events. Similar analyses were made on precipitation representing 66% of the precipitation falling at Winnemucca during the same period. The average isotopic composition of precipitation derived from each water vapor source was determined. More than half of the precipitation that fell at both sites during the study period originated in the tropical Pacific and traveled northeast to the Great Basin; only a small proportion traversed the Sierra Nevada. The isotopic composition of precipitation is determined by air-mass origin and its track to the collection station, mechanism of droplet formation, reequilibration within clouds, and evaporation during its passage from cloud to ground. The Rayleigh distillation model can explain the changes in isotopic composition of precipitation as an air mass is cooled pseudo-adiabatically during uplift. However, the complicated processes that take place in the rapidly convecting environment of cumulonimbus and other clouds that are common in the Great Basin, especially in summer, require modification of this model because raindrops that form in the lower portion of those clouds undergo isotopic change as they are elevated to upper levels of the clouds from where they eventually drop to the

  16. Pluvial lakes in the Great Basin of the western United States-a view from the outcrop

    NASA Astrophysics Data System (ADS)

    Reheis, Marith C.; Adams, Kenneth D.; Oviatt, Charles G.; Bacon, Steven N.

    2014-08-01

    Paleo-lakes in the western United States provide geomorphic and hydrologic records of climate and drainage-basin change at multiple time scales extending back to the Miocene. Recent reviews and studies of paleo-lake records have focused on interpretations of proxies in lake sediment cores from the northern and central parts of the Great Basin. In this review, emphasis is placed on equally important studies of lake history during the past ∼30 years that were derived from outcrop exposures and geomorphology, in some cases combined with cores. Outcrop and core records have different strengths and weaknesses that must be recognized and exploited in the interpretation of paleohydrology and paleoclimate. Outcrops and landforms can yield direct evidence of lake level, facies changes that record details of lake-level fluctuations, and geologic events such as catastrophic floods, drainage-basin changes, and isostatic rebound. Cores can potentially yield continuous records when sampled in stable parts of lake basins and can provide proxies for changes in lake level, water temperature and chemistry, and ecological conditions in the surrounding landscape. However, proxies such as stable isotopes may be influenced by several competing factors the relative effects of which may be difficult to assess, and interpretations may be confounded by geologic events within the drainage basin that were unrecorded or not recognized in a core. The best evidence for documenting absolute lake-level changes lies within the shore, nearshore, and deltaic sediments that were deposited across piedmonts and at the mouths of streams as lake level rose and fell. We review the different shorezone environments and resulting deposits used in such reconstructions and discuss potential estimation errors. Lake-level studies based on deposits and landforms have provided paleohydrologic records ranging from general changes during the past million years to centennial-scale details of fluctuations during the

  17. Methods for delineating flood-prone areas in the Great Basin of Nevada and adjacent states

    USGS Publications Warehouse

    Burkham, D.E.

    1988-01-01

    The Great Basin is a region of about 210,000 square miles having no surface drainage to the ocean; it includes most of Nevada and parts of Utah, California, Oregon, Idaho, and Wyoming. The area is characterized by many parallel mountain ranges and valleys trending north-south. Stream channels usually are well defined and steep within the mountains, but on reaching the alluvial fan at the canyon mouth, they may diverge into numerous distributary channels, be discontinuous near the apex of the fan, or be deeply entrenched in the alluvial deposits. Larger rivers normally have well-defined channels to or across the valley floors, but all terminate at lakes or playas. Major floods occur in most parts of the Great Basin and result from snowmelt, frontal-storm rainfall, and localized convective rainfall. Snowmelt floods typically occur during April-June. Floods resulting from frontal rain and frontal rain on snow generally occur during November-March. Floods resulting from convective-type rainfall during localized thunderstorms occur most commonly during the summer months. Methods for delineating flood-prone areas are grouped into five general categories: Detailed, historical, analytical, physiographic, and reconnaissance. The detailed and historical methods are comprehensive methods; the analytical and physiographic are intermediate; and the reconnaissance method is only approximate. Other than the reconnaissance method, each method requires determination of a T-year discharge (the peak rate of flow during a flood with long-term average recurrence interval of T years) and T-year profile and the development of a flood-boundary map. The procedure is different, however, for each method. Appraisal of the applicability of each method included consideration of its technical soundness, limitations and uncertainties, ease of use, and costs in time and money. Of the five methods, the detailed method is probably the most accurate, though most expensive. It is applicable to

  18. Holocene Climate and Environmental Change in the Great Basin of the Western United States: A Paleolimnological Approach

    NASA Astrophysics Data System (ADS)

    Reinemann, Scott Alan

    In this dissertation, I have completed a research project that focused on reconstructing past climate and environmental conditions in the Great Basin of the western United States. This research project incorporates four discrete but interrelated studies. (1) The geochemistry of lake sediments was used to identify anthropogenic factors influencing aquatic ecosystems of sub-alpine lakes in the western United States during the past century. Sediment cores were recovered from six high elevation lakes in the central Great Basin of the United States. Mercury (Hg) flux varied among lakes but all exhibited increasing fluxes during the mid-20th century and declining fluxes during the late 20th century. Peak Spheroidal Carbonaceous Particles (SCP) flux for all lakes occurred at approximately 1970, after which SCP flux was greatly reduced. Atmospheric deposition is the primary source of Hg and anthropogenically produced SCPs to these pristine high elevation lakes during the late 20th century. ( 2) Chironomids are used to develop centennial length temperature reconstructions for six sub-alpine and alpine lakes in the central Great Basin of the United States. Chironomid-inferred temperature estimates indicate that four of the six lakes were characterized by above average air temperatures during the post-AD 1980 interval and below average temperatures during the early 20 th century. This study adds to the growing body of evidence that sub-alpine and alpine lakes in the western United States have been, and are increasingly being affected by anthropogenic climate change in the early 21st century. (3) A sediment core representing the past two millennia was recovered from Stella Lake in the Snake Range of the central Great Basin in Nevada. The core was analyzed for sub-fossil chironomids and sediment organic content. The chironomid-based mean July air temperature (MJAT) reconstruction suggests that the Medieval Climate Anomaly (MCA), was characterized by MJAT elevated 1.0°C above

  19. Resistivity Architecture and Physical State of the Great Basin: Separate and Joint Roles of Fluids and Graphite

    NASA Astrophysics Data System (ADS)

    Doerner, W. M.; Wannamaker, P. E.; Sodergren, T. L.; Stodt, J. A.; Hasterok, D. P.; Unsworth, M. J.

    2002-12-01

    Dense profiles of MT soundings in the active Great Basin extensional province and the neighboring stable Colorado Plateau are integrated to provide a view of large scale structure, tectonic activity, fluid state, thermal regime and strength of the crust and upper mantle. Resistivity cross sections were derived from the MT data over the period range 0.005-10,000 s, subjected to strike analysis, using a 2-D inversion algorithm damping model departures against a-priori structure. To first order, Great Basin resistivity structure is one of a moderately conductive, Phanerozoic sedimentary section fundamentally disrupted by intrusion and uplift of resistive crystalline rocks. Early and Late Paleozoic, low-resistivity graphitized shales form important conductive marker sequences in the stratigraphy for unraveling structure. Degree of graphitization and conductance correlates with that of compressional shear deformation and hydrocarbon source maturity. Resistive crystalline core complex massifs adjoin their host stratigraphy across crustal-scale, steeply-dipping fault zones providing pathways to the lower crust for heterogeneous, upper crustal induced, electric current flow. The numerous crustal breaks imaged with MT may contribute to the low effective elastic thickness (Te) estimated for the Great Basin and exemplify the mid-crustal, steeply dipping slip zones in which major earthquakes appear to nucleate. We find the most important domain for graphite in conductivity to be the upper half or brittle regime of the crust with an origin in organic-bearing sedimentary rocks, but with important later remobilization by fluids during thermal events. Average lower crustal resistivity is low under both central and eastern Great Basin sub-provinces and is quasi one-dimensional. Deep temperatures and volcanic products suggest oxidizing conditions in the lower crust, so high conductivity is interpreted to reflect a low porosity (<1 vol. %) of hypersaline brines and possible water

  20. Estimated Withdrawals and Other Elements of Water Use in the Great Lakes Basin of the United States in 2005

    USGS Publications Warehouse

    Mills, Patrick C.; Sharpe, Jennifer B.

    2010-01-01

    Estimates of water withdrawals in the United States part of the Great Lakes Basin and 107 of its watersheds designated by the 8-digit hydrologic unit code (HUCs) indicate that about 30.3 billion gallons per day (Bgal/d) were withdrawn for practically all categories of use in 2005. Virtually all water withdrawn was freshwater. Surface-water withdrawals totaled 28.8 Bgal/d, or 95 percent of total withdrawals; about 24 Bgal/d was withdrawn from the Great Lakes or their connecting channels. Total withdrawals, and total surface-water withdrawals, decreased 7 percent from 1995 to 2005, generally following the withdrawal trends of industrial use and that of the largest use-thermoelectric power. Groundwater withdrawals increased 3 percent from 1995 to 2005 and 33 percent during 1985-2005. The substantial increase since 1985 results primarily from increases in irrigation and self-supplied domestic withdrawals. In 2005, withdrawals for public supply, domestic, and irrigation use accounted for 81 percent of groundwater withdrawals. About 21.9 Bgal/d, or 72 percent of total withdrawals for 2005, was used for thermoelectric power. Virtually all of this water was derived from surface water and used for once-through cooling at powerplants. As such, the reuse potential of this water in the basin is high, with the majority of the withdrawn water returned to its surface-water source. Public-supply withdrawals were 3.81 Bgal/d (13 percent), with withdrawals declining by about 13 percent from 1995 to 2005. In 2005, about 77 percent of the population in the Great Lakes Basin obtained drinking water from public suppliers, compared to about 78 percent in 1995 and 83 percent in 1985. Surface water consistently provided about 88 percent of the total withdrawals for public supply since 1985. Self-supplied industrial withdrawals in 2005 totaled 2.93 Bgal/d (10 percent), possibly as much as 30 percent less than in 1995. Surface water was the source for 95 percent of industrial withdrawals

  1. Estimating recharge distribution by incorporating runoff from mountainous areas in an alluvial basin in the Great Basin region of the southwestern United States.

    PubMed

    Stone, D B; Moomaw, C L; Davis, A

    2001-01-01

    A method is described to estimate the distribution of ground water recharge within hydrographic basins in the Great Basin region of the southwestern United States on the basis of estimated runoff from high mountainous areas and subsequent infiltration in alluvial fans surrounding the intermontane basins. The procedure involves a combination of Geographic Information System (GIS) analysis, empirical surface-runoff modeling, and water-balance calculations. The method addresses the need to develop and incorporate constraints on the distribution of recharge in regional-scale ground water flow modeling of arid and semiarid environments. The conceptual approach and methodology were developed for Crescent Valley, Nevada. However, the concept and method are generally applicable to any region where excess precipitation in upland areas is conveyed to lower elevations before it infiltrates to recharge the ground water system. Application of the procedure to a ground water flow model of Crescent Valley appears both qualitatively and quantitatively to result in a more accurate representation of actual recharge conditions than might otherwise have been prescribed. PMID:11708447

  2. Upper Cenozoic basalts with high Sr-87/Sr-86 and Sr/Rb ratios, southern Great Basin, western United States.

    NASA Technical Reports Server (NTRS)

    Hedge, C. E.; Noble, D. C.

    1971-01-01

    The initial strontium isotopic composition of 15 mafic volcanic rocks from the southern Great Basin has been determined. Results indicate that the basalts must have been derived from unusual mantle material in which an originally high Rb/Sr ratio was markedly lowered during an earlier phase of magmatic activity.

  3. The role of interbasin groundwater transfers in geologically complex terranes, demonstrated by the Great Basin in the western United States

    NASA Astrophysics Data System (ADS)

    Nelson, Stephen T.; Mayo, Alan L.

    2014-06-01

    In the Great Basin, USA, bedrock interbasin flow is conceptualized as the mechanism by which large groundwater fluxes flow through multiple basins and intervening mountains. Interbasin flow is propounded based on: (1) water budget imbalances, (2) potential differences between basins, (3) stable isotope evidence, and (4) modeling studies. However, water budgets are too imprecise to discern interbasin transfers and potential differences may exist with or without interbasin fluxes. Potentiometric maps are dependent on conceptual underpinnings, leading to possible false inferences regarding interbasin transfers. Isotopic evidence is prone to non-unique interpretation and may be confounded by the effects of climate change. Structural and stratigraphic considerations in a geologically complex region like the Great Basin should produce compartmentalization, where increasing aquifer size increases the odds of segmentation along a given flow path. Initial conceptual hypotheses should explain flow with local recharge and short flow paths. Where bedrock interbasin flow is suspected, it is most likely controlled by diversion of water into the damage zones of normal faults, where fault cores act as barriers. Large-scale bedrock interbasin flow where fluxes must transect multiple basins, ranges, and faults at high angles should be the conceptual model of last resort.

  4. Regional and Local Controls on the Distribution of Geothermal Systems in the Great Basin, Western United States

    NASA Astrophysics Data System (ADS)

    Coolbaugh, M. F.; Blewitt, G.; Faulds, J. E.; Kreemer, C. W.

    2005-12-01

    In the Great Basin (GB) of the western United States, geothermal systems with reservoir temperatures in excess of 150 C can be classified into two main categories (magmatic and amagmatic) according to the presence or absence of shallow magmatic heat sources. Magmatic systems are restricted to the margins of the GB where they are closely associated with Quaternary silicic volcanic rocks, whereas amagmatic systems occur over a large portion of the Great Basin interior and are not spatially associated with young silicic volcanism. A tabulation of temperature gradients for known geothermal systems in the world confirms research by others indicating that both magmatic and amagmatic systems occur within areas of high temperature gradients and high heat flow. However, high heat flow alone is not sufficient to explain the abundance of high-temperature geothermal activity in the GB interior. While the distribution of favorable host rocks likely plays a role, active crustal tectonics appears instrumental in explaining patterns of geothermal activity. At a detailed scale, Quaternary faults control the location of most geothermal systems in the GB. However, hundreds of Quaternary faults are distributed throughout the GB, and most do not host high-temperature geothermal resources. Spatial statistical analysis demonstrates that high-temperature geothermal systems (more than 150 C) are preferentially associated with NE-striking Quaternary faults, which in turn are oriented roughly perpendicular to the current direction of crustal extension in the western GB. Maps of active crustal extension rates in the GB, derived from Global Positioning System (GPS) velocity measurements and estimated slip rates on Quaternary faults, correlate well with the distribution of high-temperature geothermal systems and help explain why some faults with lower slip rates or unfavorable orientations don't host geothermal activity. Many geothermal systems in the GB occur in a broad transitional region

  5. Out of the tropics: the Pacific, Great Basin lakes, and late Pleistocene water cycle in the western United States

    USGS Publications Warehouse

    Lyle, Mitchell; Heusser, Linda; Ravelo, Christina; Yamamoto, Masanobu; Barron, John; Diffenbaugh, Noah S.; Herbert, Timothy; Andreasen, Dyke

    2012-01-01

    The water cycle in the western U.S. changed dramatically over glacial cycles. In the last 20,000 years, higher precipitation caused desert lakes to form which have since dried out. Higher glacial precipitation is hypothesized to result from a southward shift of Pacific winter storm tracks. We compared Pacific Ocean data to lake levels from the interior west and found that Great Basin lake high stands are older than coastal wet periods at the same latitude. Westerly storms were not the source of high precipitation. Instead, air masses from the tropical Pacific were transported northward, bringing more precipitation into the Great Basin when coastal California was still dry. The changing climate during the deglaciation altered precipitation source regions and strongly affected the regional water cycle.

  6. Scientific review of great basin wildfire issues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The University Nevada Reno, College of Agriculture and Resource Concepts Inc., co-sponsored a Great Basin Wildfire Forum in September 2007 to address a “Scientific Review of the Ecological and Management History of Great Basin Natural Resources and Recommendations to Achieve Ecosystem Restoration”. ...

  7. Scientific Review of Great Basin Wildfire Issues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The University Nevada Reno, College of Agriculture and Resource Concepts Inc., co-sponsored a Great Basin Wildfire Forum in September 2007 to address a “Scientific Review of the Ecological and Management History of Great Basin Natural Resources and Recommendations to Achieve Ecosystem Restoration”. ...

  8. Compilation of Regional Ground-Water Divides for Principal Aquifers Corresponding to the Great Lakes Basin, United States

    USGS Publications Warehouse

    Sheets, R.A.; Simonson, L.A.

    2006-01-01

    A compilation of regional ground-water divides for the five principal aquifers corresponding to the Great Lakes Basin within the United States is presented. The principal aquifers (or aquifer systems) are the Cambrian-Ordovician aquifer system, Silurian-Devonian aquifers, Mississippian aquifers, Pennsylvanian aquifers, and the surficial aquifer system. The regional ground-water divides mark the boundary between ground-water flow that discharges to the Great Lakes or their tributaries and ground-water flow that discharges to other major surface-water bodies, such as the Mississippi River. Multicounty to multistate (regional) hydrologic studies of the five principal aquifers were reviewed to determine whether adequate data, such as potentiometric surfaces or ground-water divides, were available from which ground-water flow directions or ground-water-divide locations could be derived. Examination of regional studies indicate that the regional ground-water divides for the Cambrian-Ordovician aquifer system and Silurian-Devonian aquifers have changed over time and differ from the surface-water divides in some areas. These differences can be attributed to either pumping or natural processes. The limited information on the shallow Mississippian and Pennsylvanian bedrock aquifers indicate that these aquifers and the surficial aquifer system act as one hydrostratigraphic unit and that downdip flow is insignificant. Generally, in the Mississippian and Pennsylvanian aquifers, regional ground-water divides are similar to regional surface-water divides. Previous studies of the regional ground-water divide of the surficial aquifer system depict the regional ground-water divide as generally following the regional surface-water divide. Because studies commonly focus on areas where ground-water use from an aquifer system is concentrated, the regional ground-water divides are not known in large, unstudied parts of some of these aquifer systems. A composite ground-water divide for

  9. Derivation of S and Pb in phanerozoic intrusion-related metal deposits from neoproterozoic sedimentary pyrite, Great Basin, United States

    USGS Publications Warehouse

    Vikre, P.G.; Poulson, S.R.; Koenig, A.E.

    2011-01-01

    The thick (???8 km), regionally extensive section of Neoproterozoic siliciclastic strata (terrigenous detrital succession, TDS) in the central and eastern Great Basin contains sedimentary pyrite characterized by mostly high d34S values (-11.6 to 40.8%, <70% exceed 10%; 51 analyses) derived from reduction of seawater sulfate, and by markedly radiogenic Pb isotopes ( 207Pb/204Pb <19.2; 15 analyses) acquired from clastic detritus eroded from Precambrian cratonal rocks to the east-southeast. In the overlying Paleozoic section, Pb-Zn-Cu-Ag-Au deposits associated with Jurassic, Cretaceous, and Tertiary granitic intrusions (intrusion-related metal deposits) contain galena and other sulfide minerals with S and Pb isotope compositions similar to those of TDS sedimentary pyrite, consistent with derivation of deposit S and Pb from TDS pyrite. Minor element abundances in TDS pyrite (e.g., Pb, Zn, Cu, Ag, and Au) compared to sedimentary and hydrothermal pyrite elsewhere are not noticeably elevated, implying that enrichment in source minerals is not a precondition for intrusion-related metal deposits. Three mechanisms for transferring components of TDS sedimentary pyrite to intrusion-related metal deposits are qualitatively evaluated. One mechanism involves (1) decomposition of TDS pyrite in thermal aureoles of intruding magmas, and (2) aqueous transport and precipitation in thermal or fluid mixing gradients of isotopically heavy S, radiogenic Pb, and possibly other sedimentary pyrite and detrital mineral components, as sulfide minerals in intrusion-related metal deposits. A second mechanism invokes mixing and S isotope exchange in thermal aureoles of Pb and S exsolved from magma and derived from decomposition of sedimentary pyrite. A third mechanism entails melting of TDS strata or assimilation of TDS strata by crustal or mantle magmas. TDS-derived or assimilated magmas ascend, decompress, and exsolve a mixture of TDS volatiles, including isotopically heavy S and radiogenic Pb

  10. Water Resources Data for California, Water Year 1986. Volume 4. Northern Central Valley Basins and the Great Basin from Honey Lake Basin to Oregon State Line

    USGS Publications Warehouse

    Mullen, J.R.; Shelton, W.F.; Simpson, R.G.; Grillo, D.A.

    1988-01-01

    Water resources data for the 1986 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 4 contains discharge records for 156 gaging stations; stage and contents for 37 lakes and reservoirs; water precipitation data for 2 stations; and water quality for 8 stations. Also included is one water-quality partial-record station. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  11. Water Resources Data, California, Water Year 1990. Volume 4. Northern Central Valley Basins and the Great Basin from Honey Lake Basin to Oregon State Line

    USGS Publications Warehouse

    Mullen, J.R.; Shelton, W.F.; Markham, K.L.; Anderson, S.W.

    1991-01-01

    Water resources data for the 1990 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 4 contains discharge records for 182 gaging stations; stage and contents for 34 lakes and reservoirs; precipitation data for 3 stations; and water quality. for 12 stations. Also included is one low-flow partial-record station. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  12. Water Resources Data, California, Water Year 1989. Volume 4. Northern Central Valley Basins and the Great Basin from Honey Lake Basin to Oregon State Line

    USGS Publications Warehouse

    Anderson, S.W.; Mullen, J.R.; Shelton, W.F.

    1990-01-01

    Water resources data for the 1989 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 4 contains discharge records for 177 gaging stations; stage and contents for 34 lakes and reservoirs; precipitation data for 3 stations; and water quality for 9 stations. Also included is one low-flow partial-record station. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  13. Water Resources Data for California, Water Year 1985. Volume 4. Northern California Valley Basins and the Great Basin from Honey Lake Basin to Oregon State Line

    USGS Publications Warehouse

    Mullen, J.R.; Shelton, W.F.; Simpson, R.G.; Grillo, D.A.

    1987-01-01

    Water resources data for the 1985 water year for California consists of records of stage, discharge, and water quality of streams; and stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 4 contains discharge records for 155 gaging stations; stage and contents for 29 lakes and reservoirs; water precipitation data for 2 stations; and water quality for 16 stations. Also included are 7 water-quality partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  14. Water Resources Data for California, Water Year 1988. Volume 4. Northern Central Valley Basins and The Great Basin from Honey Lake Basin to Oregon State Line

    USGS Publications Warehouse

    Shelton, W.F.; Anderson, S.W.; Mullen, R.J.

    1989-01-01

    Water resources data for the 1988 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wellso Volume 4 contains discharge records for 160 gaging stations; stage and contents for 35 lakes and reservoirs; water precipitation data for 2 stations; and water quality for 9 stations Also included is one low-flow partial-record station. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  15. Water Resources Data for California, Water Year 1987. Volume 4. Northern Central Valley Basins and The Great Basin from Honey Lake Basin to Oregon State Line

    USGS Publications Warehouse

    Mullen, J.R.; Shelton, W.F.; Simpson, R.G.

    1988-01-01

    Water resources data for the 1987 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 4 contains discharge records for 154 gaging stations; stage and contents for 33 lakes and reservoirs; water precipitation data for 2 stations; and water quality for 5 stations. Also included is one low-flow partial-record station. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  16. Water Resources Data, California, Water Year 1997. Volume 4. Northern Central Valley Basins and the Great Basin from Honey Lake Basin to Oregon State Line

    USGS Publications Warehouse

    Rockwell, G.L.; Friebel, M.F.; Webster, M.D.; Anderson, S.W.

    1998-01-01

    Water-resources data for the 1997 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 4 contains discharge records for 176 gaging stations and 1 partial-record station, stage and contents for 45 lakes and reservoirs, gage-height records for 3 stations, precipitation data for 3 stations, and water quality data for 14 stations and 6 waterquality partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  17. Water Resources Data -- California, Water Year 2003, Volume 4. Northern Central Valley Basins and The Great Basin from Honey Lake Basin to Oregon State Line

    USGS Publications Warehouse

    Friebel, M.F.; Webster, M.D.; Rockwell, G.L.; Smithson, J.R.

    2004-01-01

    Water-resources data for the 2003 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 4 contains discharge records for 195 gaging stations, stage and contents for 62 lakes and reservoirs, gage-height records for 1 station, water quality for 33 streamflow-gaging stations and 8 partial-record stations. Also included are 4 miscellaneous partial-record sites. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  18. Water Resources Data--California, Water Year 2001. Volume 4. Northern Central Valley Basins and The Great Basin from Honey Lake Basin to Oregon State Line

    USGS Publications Warehouse

    Rockwell, G.L.; Smithson, J.R.; Friebel, M.F.; Webster, M.D.

    2002-01-01

    Water-resources data for the 2001 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 4 contains discharge records for 191 gaging stations, stage and contents for 53 lakes and reservoirs, gage-height records for 1 station, and water quality for 18 stations. Also included are 3 miscellaneous partial-record sites, and 3 parital-record water-quality stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  19. Water Resources Data, California, Water Year 1998. Volume 4. Northern Central Valley Basins and the Great Basin from Honey Lake Basin to Oregon State Line

    USGS Publications Warehouse

    Friebel, M.F.; Webster, M.D.; Anderson, S.W.; Rockwell, G.L.; Smithson, J.R.

    1999-01-01

    Water-resources data for the 1998 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 4 contains discharge records for 176 gaging stations and 1 partial-record station, stage and contents for 45 lakes and reservoirs, gage-height records for 1 station, precipitation data for 3 stations, and water quality for 14 stations and 7 waterquality partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  20. Water Resources Data--California, Water Year 2000. Volume 4. Northern Central Valley Basins and The Great Basin from Honey Lake Basin to Oregon State Line

    USGS Publications Warehouse

    Anderson, S.W.; Rockwell, G.L.; Smithson, J.R.; Friebel, M.F.; Webster, M.D.

    2001-01-01

    Water-resources data for the 2000 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 4 contains discharge records for 190 gaging stations and 5 partial-record stations, stage and contents for 60 lakes and reservoirs, gage-height records for 1 station, precipitation data for 3 stations, and water quality for 10 stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  1. Water resources data-California, water year 2004. volume 4. northern central valley basins and the Great Basin from Honey Lake basin to Oregon state line

    USGS Publications Warehouse

    Webster, M.D.; Rockwell, G.L.; Friebel, M.F.; Brockner, S.J.

    2005-01-01

    Water-resources data for the 2004 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 4 contains discharge records for 188 gaging stations, stage and contents for 62 lakes and reservoirs, gage-height records for 1 station, water quality for 20 streamflow-gaging stations and 1 partial-record stations. Also included are 4 miscellaneous partial-record sites. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  2. Water Resources Data--California, Water Year 2002, Volume 4. Northern Central Valley Basins and The Great Basin from Honey Lake Basin to Oregon State Line

    USGS Publications Warehouse

    Smithson, J.R.; Friebel, M.F.; Webster, M.D.; Rockwell, G.L.

    2002-01-01

    Water-resources data for the 2002 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 4 contains discharge records for 191 gaging stations, stage and contents for 60 lakes and reservoirs, gage-height records for 2 stations, and water quality for 21 stations. Also included are 4 miscellaneous partial-record sites. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  3. Water Resources Data, California, Water Year 1996. Volume 4. Northern Central Valley Basins and the Great Basin from Honey Lake Basin to Oregon State Line

    USGS Publications Warehouse

    Anderson, S.W.; Rockwell, G.L.; Friebel, M.F.; Webster, M.D.

    1997-01-01

    Water-resources data for the 1996 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 4 contains discharge records for 180 gaging stations, stage and contents for 45 lakes and reservoirs, gage-height records for 5 stations, precipitation data for 3 stations, and water quality for 15 stations. Also included is 1 low-flow partial-record station. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  4. Water Resources Data for California, water year 1984. Volume 4. Northern Central Valley Basins and the Great Basin from Honey Lake Basin to Oregon State Line

    USGS Publications Warehouse

    Fogelman, R.P.; Mullen, J.R.; Shelton, W.F.; Simpson, R.G.; Grillo, D.A.

    1986-01-01

    Water resources data for the 1984 water year for California consists of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 4 contains discharge records for 152 gaging stations; stage and contents for 25 lakes and reservoirs; water precipitation data for 2 stations; water quality for 9 stations; water levels for 12 and water quality for 46 observation wells. Also included is one low-flow partialrecord station and 19 water-quality partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and federal agencies in California.

  5. Water Resources Data for California Water Year 1982, Volume 4. Northern California Valley Basins and the Great Basin from Honey Lake Basin to Oregon State Line

    USGS Publications Warehouse

    Fogelman, R.P.; Mullen, J.R.; Shelton, W.F.; Simpson, R.G.

    1984-01-01

    Water-resources data for the 1982 water year for California consists of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 4 contains discharge records for 163 gaging stations; stage and contents for 27 lakes and reservoirs; precipitation data for 2 stations; water quality for 7 stations; and water levels for 54 observation wells, Also included are 4 crest-stage partial-record stations and 4 low-flow partial-record stations. Additional wator data are collected at various sites, not part of the systematic data collection program, and are published as special investigations. These data represent that part of the National Water Data System operated by the u.s. Geological Survey and cooperating State and Federal agencies in California.

  6. Water Resources Data for California, Water Year 1983, Volume 4. Northern California Valley Basins and the Great Basin from Honey Lake Basin to Oregon State Line

    USGS Publications Warehouse

    Fogelman, R.P.; Mullen, J.R.; Shelton, W.F.; Simpson, R.G.; Grillo, D.A.

    1985-01-01

    Water-resources data for the 1983 water year for California consists of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 4 contains discharge records for 153 gaging stations; stage and contents for 25 lakes and reservoirs; precipitation data for 2 stations; water quality for 7 stations; and water levels for 147 observation wells. Also included is one low-flow partial-record station. Additional water data are collected at various sites, not part of the systematic data collection program, and are published as special investigations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  7. Ordovician chitinozoan zones of Great Basin

    SciTech Connect

    Hutter, T.J.

    1987-08-01

    Within the Basin and Range province of the Great Basin of the western US, Ordovician chitinozoans have been recovered in two major lithic facies; the western eugeosynclinal facies and the eastern miogeosynclinal facies. Chitinozoans recovered from these facies range in age from Arenig to Ashgill. Extensive collections from this area make possible the establishment of chitinozoan faunal interval zones from the Ordovician of this area. Selected species of biostratigraphic value include, in chronostratigraphic order, Lagenochitina ovoidea Benoit and Taugourdeau, 1961, Conochitina langei Combaz and Peniguel, 1972, Conochitinia poumoti Combaz and Penique, Desmochitina cf. nodosa Eisenack, 1931, Conochitina maclartii Combaz and Peniguel, 1972, Conochitina robusta Eisenack, 1959, Angochitina capitallata Eisenack, 1937, Sphaerochitina lepta Jenkins. 1970, and Ancyrochitina merga Jenkins, 1970. In many cases, these zones can be divided into additional sub-zones using chitinozoans and acritarchs. In all cases, these chitinozoan faunal zones are contrasted with established American graptolite zones of the area, as well as correlated with British standard graptolite zones. The composition of these faunas of the western US Great Basin is similar to that of the Marathon region of west Texas and the Basin Ranges of Arizona and New Mexico, to which direct comparisons have been made. There also appears to be a great similarity with the microfaunas and microfloras of the Ordovician of the Canning basin of western Australia. The Ordovician chitinozoan faunal interval zones established for the Basin and Range province of the Great Basin of the western US also appear to be applicable to the Marathon region of west Texas and the Basin Ranges of Arizona and New Mexico.

  8. Estimation of monthly water yields and flows for 1951-2012 for the United States portion of the Great Lakes Basin with AFINCH

    USGS Publications Warehouse

    Luukkonen, Carol L.; Holtschlag, David J.; Reeves, Howard W.; Hoard, Christopher J.; Fuller, Lori M.

    2015-01-01

    Monthly water yields from 105,829 catchments and corresponding flows in 107,691 stream segments were estimated for water years 1951–2012 in the Great Lakes Basin in the United States. Both sets of estimates were computed by using the Analysis of Flows In Networks of CHannels (AFINCH) application within the NHDPlus geospatial data framework. AFINCH provides an environment to develop constrained regression models to integrate monthly streamflow and water-use data with monthly climatic data and fixed basin characteristics data available within NHDPlus or supplied by the user. For this study, the U.S. Great Lakes Basin was partitioned into seven study areas by grouping selected hydrologic subregions and adjoining cataloguing units. This report documents the regression models and data used to estimate monthly water yields and flows in each study area. Estimates of monthly water yields and flows are presented in a Web-based mapper application. Monthly flow time series for individual stream segments can be retrieved from the Web application and used to approximate monthly flow-duration characteristics and to identify possible trends.

  9. Late quaternary geomorphology of the Great Salt Lake region, Utah, and other hydrographically closed basins in the western United States: A summary of observations

    NASA Technical Reports Server (NTRS)

    Currey, Donald R.

    1989-01-01

    Attributes of Quaternary lakes and lake basins which are often important in the environmental prehistory of semideserts are discussed. Basin-floor and basin-closure morphometry have set limits on paleolake sizes; lake morphometry and basin drainage patterns have influenced lacustrine processes; and water and sediment loads have influenced basin neotectonics. Information regarding inundated, runoff-producing, and extra-basin spatial domains is acquired directly from the paleolake record, including the littoral morphostratigraphic record, and indirectly by reconstruction. Increasingly detailed hypotheses regarding Lake Bonneville, the largest late Pleistocene paleolake in the Great Basin, are subjects for further testing and refinement. Oscillating transgression of Lake Bonneville began about 28,000 yr B.P.; the highest stage occurred about 15,000 yr B.P., and termination occurred abruptly about 13,000 yr B.P. A final resurgence of perennial lakes probably occurred in many subbasins of the Great Basin between 11,000 and 10,000 yr B.P., when the highest stage of Great Salt Lake (successor to Lake Bonneville) developed the Gilbert shoreline. The highest post-Gilbert stage of Great Salt Lake, which has been one of the few permanent lakes in the Great Basin during Holocene time, probably occurred between 3,000 and 2,000 yr B.P.

  10. INDICATORS OF GREAT BASIN RANGELAND HEALTH

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Early-warning indicators of rangeland health can be used to estimate the functional integrity of a site and may allow sustainable management of desert rangelands. The utility of several vegetation canopy-based indicators of rangeland health at 32 Great Basin rangeland locations was investigated. T...

  11. The Great Basin Research and Management Partnership

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Great Basin is undergoing major sociological and ecological change as a result of urbanization, changing technology and land use, climate change, limited water resources, altered fire regimes, and invasive species, insects, and disease. Sustaining ecosystems, resources, and human populations of...

  12. SE Great Basin Play Fairway Analysis

    DOE Data Explorer

    Adam Brandt

    2015-11-15

    Within this submission are multiple .tif images with accompanying metadata of magnetotelluric conductor occurrence, fault critical stress composite risk segment (CRS), permeability CRS, Quaternary mafic extrusions, Quaternary fault density, and Quaternary rhyolite maps. Each of these contributed to a final play fairway analysis (PFA) for the SE Great Basin study area.

  13. A Network for Observing Great Basin Climate Change

    NASA Astrophysics Data System (ADS)

    Mensing, Scott; Strachan, Scotty; Arnone, Jay; Fenstermaker, Lynn; Biondi, Franco; Devitt, Dale; Johnson, Brittany; Bird, Brian; Fritzinger, Eric

    2013-03-01

    The ability to evaluate accurately the response of the environment to climate change ideally involves long-term continuous in situ measurements of climate and landscape processes. This is the goal of the Nevada Climate-Ecohydrology Assessment Network (NevCAN), a novel system of permanent monitoring stations located across elevational and latitudinal gradients within the Great Basin hydrographic region (Figure 1). NevCAN was designed, first, to quantify the daily, seasonal, and interannual variability in climate that occurs from basin valleys to mountain tops of the Great Basin in the arid southwest of the United States; second, to relate the temporal patterns of ecohydrologic response to climate occurring within each of the major ecosystems that compose the Great Basin; and, last, to monitor changes in climate that modulate water availability, sequestration of carbon, and conservation of biological diversity.

  14. Sustainability Within the Great Monsoon River Basins

    NASA Astrophysics Data System (ADS)

    Webster, P. J.

    2014-12-01

    For over five millenia, the great monsoon river basins of the Ganges, Brahmaputra and Indus have provided for great and flourishing agrarian civilizations. However, rapid population growth and urbanization have placed stress on the rural sector causing the use of land that is more prone for flood and drought. In addition, increased population and farming have stressed the availability of fresh water both from rivers and aquifers. Additionally, rapid urbanization has severely reduced water quality within the great rivers. Added to these problems is delta subsidence from water withdrawal that, at the moment far surpasses sea level rise from both natural and anthropogenic effects. Finally, there appear to be great plans for river diversion that may reduce fresh water inflow into the Brahmaputra delta. All of these factors fall against a background of climate change, both anthropogenic and natural, of which there is great uncertainty. We an attempt a frank assessment assessment of the sustainability of society in the great basins and make some suggestions of factors that require attention in the short term.

  15. Base flow in the Great Lakes Basin

    USGS Publications Warehouse

    Neff, B.P.; Day, S.M.; Piggott, A.R.; Fuller, L.M.

    2005-01-01

    Hydrograph separations were performed using the PART, HYSEP 1, 2, and 3, BFLOW and UKIH methods on 104,293 years of daily streamflow records from 3,936 streamflow-gaging stations in Ontario, Canada and the eight Great Lakes States of Illinois, Indiana, Michigan, Minnesota, New York, Ohio, Pennsylvania, and Wisconsin to estimate base-flow index (BFI) and base flow. BFI ranged an average of 0.24 BFI depending on which hydrograph-separation method was used. BFI data from 959 selected streamflow-gaging stations with a combined 28,784 years of daily streamflow data were used to relate BFI to surficial geology and the proportion of surface water within the gaged watersheds. This relation was then used to derive estimates of BFI throughout the Great Lakes, Ottawa River, and upper St. Lawrence River Basins at a scale of 8-digit hydrologic unit code (HUC) watersheds for the U.S. and tertiary watersheds in Canada. This process was repeated for each of the six hydrograph-separation methods used. When applied to gaged watersheds, model results predicted observed base flow within 0.2 BFI up to 94 percent of the time. Estimates of long-term (length of streamflow record) average annual streamflow in each HUC and tertiary watershed were calculated and used to determine average annual base flow from BFI estimates. Possibilities for future study based on results from this study include long-term trend analysis of base flow and improving the scale at which base-flow estimates can be made.

  16. Pacific salmonines in the Great Lakes Basin

    USGS Publications Warehouse

    Claramunt, Randall M.; Madenjian, Charles P.; Clapp, David

    2012-01-01

    Pacific salmon (genus Oncorhynchus) are a valuable resource, both within their native range in the North Pacific rim and in the Great Lakes basin. Understanding their value from a biological and economic perspective in the Great Lakes, however, requires an understanding of changes in the ecosystem and of management actions that have been taken to promote system stability, integrity, and sustainable fisheries. Pacific salmonine introductions to the Great Lakes are comprised mainly of Chinook salmon, coho salmon, and steelhead and have accounted for 421, 177, and 247 million fish, respectively, stocked during 1966-2007. Stocking of Pacific salmonines has been effective in substantially reducing exotic prey fish abundances in several of the Great Lakes (e.g., lakes Michigan, Huron, and Ontario). The goal of our evaluation was to highlight differences in management strategies and perspectives across the basin, and to evaluate policies for Pacific salmonine management in the Great Lakes. Currently, a potential conflict exists between Pacific salmonine management and native fish rehabilitation goals because of the desire to sustain recreational fisheries and to develop self-sustaining populations of stocked Pacific salmonines in the Great Lakes. We provide evidence that suggests Pacific salmonines have not only become naturalized to the food webs of the Great Lakes, but that their populations (specifically Chinook salmon) may be fluctuating in concert with specific prey (i.e., alewives) whose populations are changing relative to environmental conditions and ecosystem disturbances. Remaining questions, however, are whether or not “natural” fluctuations in predator and prey provide enough “stability” in the Great Lakes food webs, and even more importantly, would a choice by managers to attempt to reduce the severity of predator-prey oscillations be antagonistic to native fish restoration efforts. We argue that, on each of the Great Lakes, managers are pursuing

  17. SE Great Basin Play Fairway Analysis

    SciTech Connect

    Adam Brandt

    2015-11-15

    This submission includes a Na/K geothermometer probability greater than 200 deg C map, as well as two play fairway analysis (PFA) models. The probability map acts as a composite risk segment for the PFA models. The PFA models differ in their application of magnetotelluric conductors as composite risk segments. These PFA models map out the geothermal potential in the region of SE Great Basin, Utah.

  18. Geothermal fluid genesis in the Great Basin

    SciTech Connect

    Flynn, T.; Buchanan, P.K.

    1990-01-01

    Early theories concerning geothermal recharge in the Great Basin implied recharge was by recent precipitation. Physical, chemical, and isotopic differences between thermal and non-thermal fluids and global paleoclimatic indicators suggest that recharge occurred during the late Pleistocene. Polar region isotopic studies demonstrate that a depletion in stable light-isotopes of precipitation existed during the late Pleistocene due to the colder, wetter climate. Isotopic analysis of calcite veins and packrat midden megafossils confirm the depletion event occurred in the Great Basin. Isotopic analysis of non-thermal springs is utilized as a proxy for local recent precipitation. Contoured plots of deuterium concentrations from non-thermal and thermal water show a regional, systematic variation. Subtracting contoured plots of non-thermal water from plots of thermal water reveals that thermal waters on a regional scale are generally isotopically more depleted. Isolated areas where thermal water is more enriched than non-thermal water correspond to locations of pluvial Lakes Lahontan and Bonneville, suggesting isotopically enriched lake water contributed to fluid recharge. These anomalous waters also contain high concentrations of sodium chloride, boron, and other dissolved species suggestive of evaporative enrichment. Carbon-age date and isotopic data from Great Basin thermal waters correlate with the polar paleoclimate studies. Recharge occurred along range bounding faults. 151 refs., 62 figs., 15 tabs.

  19. Michigan: The Great Lakes State

    ERIC Educational Resources Information Center

    McKay, Sandra Lee; La Luzerne-Oi, Sally

    2009-01-01

    Although Michigan is often called the "Wolverine State," its more common nickname is the "Great Lakes State." This name comes from the fact that Michigan is the only state in the United States that borders four of the five Great Lakes. Also referred to as the "Water Wonderland," Michigan has 11,000 additional lakes, 36,000 miles of streams, and…

  20. Radionuclides in the Great Lakes basin.

    PubMed Central

    Ahier, B A; Tracy, B L

    1995-01-01

    The Great Lakes basin is of radiologic interest due to the large population within its boundaries that may be exposed to various sources of ionizing radiation. Specific radionuclides of interest in the basin arising from natural and artificial sources include 3H, 14C, 90Sr, 129I, 131I, 137Cs, 222Rn, 226Ra, 235U, 238U, 239Pu, and 241Am. The greatest contribution to total radiation exposure is the natural background radiation that provides an average dose of about 2.6 mSv/year to all basin residents. Global fallout from atmospheric nuclear weapons tests conducted before 1963 has resulted in the largest input of anthropogenic radioactivity into the lakes. Of increasing importance is the radionuclide input from the various components of the nuclear fuel cycle. Although the dose from these activities is currently very low, it is expected to increase if there is continued growth of the nuclear industry. In spite of strict regulations on design and operation of nuclear power facilities, the potential exists for a serious accident as a result of the large inventories of radionuclides contained in the reactor cores; however, these risks are several orders of magnitude less than the risks from other natural and man-made hazards. An area of major priority over the next few decades will be the management of the substantial amounts of radioactive waste generated by nuclear fuel cycle activities. Based on derived risk coefficients, the theoretical incidence of fatal and weighted nonfatal cancers and hereditary defects in the basin's population, attributable to 50 years of exposure to natural background radiation, is conservatively estimated to be of the order of 3.4 x 10(5) cases. The total number of attributable health effects to the year 2050 from fallout radionuclides in the Great Lakes basin is of the order of 5.0 x 10(3). In contrast, estimates of attributable health effects from 50 years of exposure to current nuclear fuel cycle effluent in the basin are of the order of 2

  1. Radionuclides in the Great Lakes basin.

    PubMed

    Ahier, B A; Tracy, B L

    1995-12-01

    The Great Lakes basin is of radiologic interest due to the large population within its boundaries that may be exposed to various sources of ionizing radiation. Specific radionuclides of interest in the basin arising from natural and artificial sources include 3H, 14C, 90Sr, 129I, 131I, 137Cs, 222Rn, 226Ra, 235U, 238U, 239Pu, and 241Am. The greatest contribution to total radiation exposure is the natural background radiation that provides an average dose of about 2.6 mSv/year to all basin residents. Global fallout from atmospheric nuclear weapons tests conducted before 1963 has resulted in the largest input of anthropogenic radioactivity into the lakes. Of increasing importance is the radionuclide input from the various components of the nuclear fuel cycle. Although the dose from these activities is currently very low, it is expected to increase if there is continued growth of the nuclear industry. In spite of strict regulations on design and operation of nuclear power facilities, the potential exists for a serious accident as a result of the large inventories of radionuclides contained in the reactor cores; however, these risks are several orders of magnitude less than the risks from other natural and man-made hazards. An area of major priority over the next few decades will be the management of the substantial amounts of radioactive waste generated by nuclear fuel cycle activities. Based on derived risk coefficients, the theoretical incidence of fatal and weighted nonfatal cancers and hereditary defects in the basin's population, attributable to 50 years of exposure to natural background radiation, is conservatively estimated to be of the order of 3.4 x 10(5) cases. The total number of attributable health effects to the year 2050 from fallout radionuclides in the Great Lakes basin is of the order of 5.0 x 10(3). In contrast, estimates of attributable health effects from 50 years of exposure to current nuclear fuel cycle effluent in the basin are of the order of 2

  2. A spatially explicit model of runoff, evaporation, and lake extent: Application to modern and late Pleistocene lakes in the Great Basin region, western United States

    NASA Astrophysics Data System (ADS)

    Matsubara, Yo; Howard, Alan D.

    2009-06-01

    A spatially explicit hydrological model was applied to the Great Basin in the western United States to predict runoff magnitude and lake distributions under modern and late Pleistocene conditions. The model iteratively routes runoff through depression to find a steady state solution and was calibrated with mean annual precipitation, pan evaporation, temperature, and stream runoff data. The predicted lake distribution provides a close match to present-day lakes. For the late Pleistocene, the sizes of lakes Bonneville and Lahontan are well predicted by linear combinations of 0.2°-5.8°C decreases in temperature and corresponding increases in precipitation from 2.0 to 1.0 times modern values. This corresponds to runoff depths ranging from 1.7 to 4.1 times the present values and yearly evaporation from 0.4 to 1 times modern values. To reproduce Lake Manly, however, combinations of temperature decreases up to 9°C or precipitation up to 2.8 times the present values were required.

  3. A 2000-yr reconstruction of air temperature in the Great Basin of the United States with specific reference to the Medieval Climatic Anomaly

    NASA Astrophysics Data System (ADS)

    Reinemann, Scott A.; Porinchu, David F.; MacDonald, Glen M.; Mark, Bryan G.; DeGrand, James Q.

    2014-09-01

    A sediment core representing the past two millennia was recovered from Stella Lake in the Snake Range of the central Great Basin in Nevada. The core was analyzed for sub-fossil chironomids and sediment organic content. A quantitative reconstruction of mean July air temperature (MJAT) was developed using a regional training set and a chironomid-based WA-PLS inference model (r2jack = 0.55, RMSEP = 0.9°C). The chironomid-based MJAT reconstruction suggests that the interval between AD 900 and AD 1300, corresponding to the Medieval Climate Anomaly (MCA), was characterized by MJAT elevated 1.0°C above the subsequent Little Ice Age (LIA), but likely not as warm as recent conditions. Comparison of the Stella Lake temperature reconstruction to previously published paleoclimate records from this region indicates that the temperature fluctuations inferred to have occurred at Stella Lake between AD 900 and AD 1300 correspond to regional records documenting hydroclimate variability during the MCA interval. The Stella Lake record provides evidence that elevated summer temperature contributed to the increased aridity that characterized the western United States during the MCA.

  4. Drainage water phosphorus losses in the great lakes basin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The great lakes are one of the most important fresh water resources on the planet. While forestry is a primary land use throughout much of the great lakes basin, there are portions of the basin, such as much of the land that drains directly to Lake Erie, that are primarily agricultural. The primary ...

  5. A regional analysis of drivers and impacts of land cover change and long-term land cover trends in the Great Basin, United States

    NASA Astrophysics Data System (ADS)

    Bradley, Bethany Adella

    An improved understanding of land use/land cover change at local and regional scales is important in an increasingly human-dominated biosphere. The land surface provides resources necessary for human survival (e.g., cropland, water, raw materials) as well as providing other services such as habitat for native species, carbon storage, and nutrient cycling. A goal of land change science is to identify where land cover change is taking place, understand how land use may affect that change, and determine what the consequences of change may be. In the Great Basin Desert of the Western U.S., an important form of land cover change is invasion by non-native cheatgrass (Bromus tectorum). Cheatgrass invasion destroys native shrub ecosystems, leading to a loss of biodiversity, loss of viable rangeland and increased fire frequency. In this work, I show how remote sensing can be used to detect the regional and local extents of cheatgrass invasion. Remote sensing results are then used to assess the spatial patterns of cheatgrass invasion over time to determine how land use might have affected invasion. Further, I consider the long-term impacts of cheatgrass invasion on biodiversity and carbon storage in the Great Basin. In addition to an analysis of cheatgrass, this thesis presents a new methodology for time series modeling, which can be used to better interpret annual and inter-annual vegetation community phenology. I apply this modeling methodology to all land cover in the Great Basin to assess long-term land cover trends and localized anomalous response within the range of land cover classes present. By investigating regional land cover change I am able to provide more detailed analysis of the drivers of change for land managers while working at a scale relevant to studies of global environmental change.

  6. Germination Characteristics Of Some Great Basin Native Annual Forb Species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Great Basin native plant communities are being replaced by the annual invasive cheatgrass (Bromus tectorum). Cheatgrass exhibits a germination syndrome that is characteristic of facultative winter annuals. Although perennials dominate these communities, native annuals are present in many sites. Germ...

  7. Geology of photo linear elements, Great Divide Basin, Wyoming

    NASA Technical Reports Server (NTRS)

    Blackstone, D. L., Jr.

    1973-01-01

    The author has identified the following significant results. Ground examination of photo linear elements in the Great Divide Basin, Wyoming indicates little if any tectonic control. Aeolian aspects are more widespread and pervasive than previously considered.

  8. Great Basin land management planning using ecological modeling.

    PubMed

    Forbis, Tara A; Provencher, Louis; Frid, Leonardo; Medlyn, Gary

    2006-07-01

    This report describes a land management modeling effort that analyzed potential impacts of proposed actions under an updated Bureau of Land Management Resource Management Plan that will guide management for 20 years on 4.6 million hectares in the Great Basin ecoregion of the United States. State-and-transition models that included vegetation data, fire histories, and many parameters (i.e., rates of succession, fire return intervals, outcomes of management actions, and invasion rates of native and nonnative invasive species) were developed through workshops with scientific experts and range management specialists. Alternative restoration scenarios included continuation of current management, full fire suppression, wildfire use in designated fire use zones, wildfire use in resilient vegetation types only, restoration with a tenfold budget increase, no restoration treatments, and no livestock grazing. Under all the scenarios, cover of vegetation states with native perennial understory declined and was replaced by tree-invaded and weed-dominated states. The greatest differences among alternative management scenarios resulted from the use of fire as a tool to maintain native understory. Among restoration scenarios, only the scenario assuming a tenfold budget increase had a more desirable outcome than the current management scenario. Removal of livestock alone had little effect on vegetation resilience. Rather, active restoration was required. The predictive power of the model was limited by current understanding of Great Basin vegetation dynamics and data needs including statistically valid monitoring of restoration treatments, invasiveness and invasibility, and fire histories. The authors suggest that such computer models can be useful tools for systematic analysis of potential impacts in land use planning. However, for a modeling effort to be productive, the management situation must be conducive to open communication among land management agencies and partner

  9. Great Basin Land Management Planning Using Ecological Modeling

    NASA Astrophysics Data System (ADS)

    Forbis, Tara A.; Provencher, Louis; Frid, Leonardo; Medlyn, Gary

    2006-07-01

    This report describes a land management modeling effort that analyzed potential impacts of proposed actions under an updated Bureau of Land Management Resource Management Plan that will guide management for 20 years on 4.6 million hectares in the Great Basin ecoregion of the United States. State-and-transition models that included vegetation data, fire histories, and many parameters (i.e., rates of succession, fire return intervals, outcomes of management actions, and invasion rates of native and nonnative invasive species) were developed through workshops with scientific experts and range management specialists. Alternative restoration scenarios included continuation of current management, full fire suppression, wildfire use in designated fire use zones, wildfire use in resilient vegetation types only, restoration with a tenfold budget increase, no restoration treatments, and no livestock grazing. Under all the scenarios, cover of vegetation states with native perennial understory declined and was replaced by tree-invaded and weed-dominated states. The greatest differences among alternative management scenarios resulted from the use of fire as a tool to maintain native understory. Among restoration scenarios, only the scenario assuming a tenfold budget increase had a more desirable outcome than the current management scenario. Removal of livestock alone had little effect on vegetation resilience. Rather, active restoration was required. The predictive power of the model was limited by current understanding of Great Basin vegetation dynamics and data needs including statistically valid monitoring of restoration treatments, invasiveness and invasibility, and fire histories. The authors suggest that such computer models can be useful tools for systematic analysis of potential impacts in land use planning. However, for a modeling effort to be productive, the management situation must be conducive to open communication among land management agencies and partner

  10. The ecology of stream and riparian habitats of the Great Basin region: A community profile

    SciTech Connect

    Minshall, G.W. . Dept. of Biological Sciences); Jensen, S.E. ); Platts, W.S. . Intermountain Forest and Range Experiment Station)

    1989-09-01

    Surface waters of the Great Basin include perennial, intermittent, and ephemeral streams; freshwater and saline lakes; playa lakes; freshwater and saline wetlands and thermal springs associated with faulting and volcanic activity. All of these aquatic habitats generally have associated riparian habitats. However, riparian habitats of the Great Basin may be more mesic than the riparian habitats of the eastern United States. The Great Basin comprises the northern half of the Basin and Range Physiographic Province and covers most of Nevada and western Utah and portions of California, Oregon, and Idaho. The entire basin actually consists of numerous subbasins and mountain ranges which present an extremely diverse physical setting. Typical mountains range from about 2100--3000 m in elevation while subbasin floors are typically 1500--1800 m in elevation. The entire Great Basin lies in the rain shadow of the Sierra Nevada Mountains and the regions is semi-arid to arid. Riparian and stream habitats within the Great Basin have received less attention from ecologists than similar habitats elsewhere in the United States. As a consequence, little is known about biotic communities or about certain aspects of structure and functioning of these ecosystems.

  11. Miocene and early Pliocene epithermal gold-silver deposits in the northern Great Basin, western United States: Characteristics, distribution, and relationship to Magmatism

    USGS Publications Warehouse

    John, D.A.

    2001-01-01

    Numerous important Miocene and early Pliocene epithermal Au-Ag deposits are present in the northern Great Basin. Most deposits are spatially and temporally related to two magmatic assemblages: bimodal basalt-rhyolite and western andesite. These magmatic assemblages are petrogenetic suites that reflect variations in tectonic environment of magma generation. The bimodal assemblage is a K-rich tholeiitic series formed during continental rifting. Rocks in the bimodal assemblage consist mostly of basalt to andesite and rhyolite compositions that generally contain anhydrous and reduced mineral assemblages (e.g., quartz + fayalite rhyolites). Eruptive forms include mafic lava flows, dikes, cinder and/or spatter cones, shield volcanoes, silicic flows, domes, and ash-flow calderas. Fe-Ti oxide barometry indicates oxygen fugacities between the magnetite-wustite and fayalite-magnetite-quartz oxygen buffers for this magmatic assemblage. The western andesite assemblage is a high K calc-alkaline series that formed a continental-margin are related to subduction of oceanic crust beneath the western coast of North America. In the northern Great Basin, most of the western andesite assemblage was erupted in the Walker Lane belt, a zone of transtension and strike-slip faulting. The western andesite assemblage consists of stratovolcanoes, dome fields, and subvolcanic plutons, mostly of andesite and dacite composition. Biotite and hornblende phenocrysts are abundant in these rocks. Oxygen fugacities of the western andesite assemblage magmas were between the nickel-nickel oxide and hematite-magnetite buffers, about two to four orders of magnitude greater than magmas of the bimodal assemblage. Numerous low-sulfidation Au-Ag deposits in the bimodal assemblage include deposits in the Midas (Ken Snyder), Sleeper, DeLamar, Mule Canyon, Buckhorn, National, Hog Ranch, Ivanhoe, and Jarbidge districts; high-sulfidation gold and porphyry copper-gold deposits are absent. Both high- and low

  12. Geothermal resources of the Washakie and Great Divide basins, Wyoming

    SciTech Connect

    Heasler, H.P.; Buelow, K.L.

    1985-01-01

    The geothermal resources of the Great Divide and Washakie Basins of southern Wyoming are described. Oil well bottomhole temperatures, thermal logs of wells, and heat flow data were interpreted within a framework of geologic and hydrologic constraints. It was concluded large areas in Wyoming are underlain by water hotter than 120{sup 0}F. Isolated areas with high temperature gradients exist within each basin. 68 refs., 8 figs., 7 tabs. (ACR)

  13. WEPP modeling in the Great Lakes Basin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA-ARS Water Erosion Prediction Project (WEPP) model is a state-of-the-art physical process-based computer simulation model for estimating runoff, soil erosion, and sediment losses from a range of land management systems, including cropland, rangeland, and forests. The National Soil Erosion Re...

  14. Biostratigraphic refinements of paleozoics of Great Basin using palynology

    SciTech Connect

    Hutter, T.J.

    1987-08-01

    Examining material from numerous wells and extensive collections of Paleozoic sediments from throughout the Great Basin shows large morphic diversity of the acritarchs, chitinozoans, and spores. Quantitative analysis of these palynomorphs provides data on biostratigraphy, paleoenvironments, and organic thermal maturation throughout the Paleozoic stratigraphic units. Biostratigraphic boundaries and associated lithostratigraphic units can be recognized by using the acritarch, chitinozoan, and spore assemblages. The Paleozoic microflora and microfauna from the Great Basin show remarkable affinities to assemblage records from western Australia. Comparisons with established graptolite and conondont zone are also established.

  15. Extent of Pleistocene lakes in the western Great Basin

    USGS Publications Warehouse

    Reheis, Marith C.

    1999-01-01

    During the Pliocene to middle Pleistocene, pluvial lakes in the western Great Basin repeatedly rose to levels much higher than those of the well-documented late Pleistocene pluvial lakes, and some presently isolated basins were connected. Sedimentologic, geomorphic, and chronologic evidence at sites shown on the map indicates that Lakes Lahontan and Columbus-Rennie were as much as 70 m higher in the early-middle Pleistocene than during their late Pleistocene high stands. Lake Lahontan at its 1400-m shoreline level would submerge present-day Reno, Carson City, and Battle Mountain, and would flood other now-dry basins. To the east, Lakes Jonathan (new name), Diamond, Newark, and Hubbs also reached high stands during the early-middle(?) Pleistocene that were 25-40 m above their late Pleistocene shorelines; at these very high levels, the lakes became temporarily or permanently tributary to the Humboldt River and hence to Lake Lahontan. Such a temporary connection could have permitted fish to migrate from the Humboldt River southward into the presently isolated Newark Valley and from Lake Lahontan into Fairview Valley. The timing of drainage integration also provides suggested maximum ages for fish to populate the basins of Lake Diamond and Lake Jonathan. Reconstructing and dating these lake levels also has important implications for paleoclimate, tectonics, and drainage evolution in the western Great Basin. For example, shorelines in several basins form a stair-step sequence downward with time from the highest levels, thought to have formed at about 650 ka, to the lowest, formed during the late Pleistocene. This descending sequence indicates progressive drying of pluvial periods, possibly caused by uplift of the Sierra Nevada and other western ranges relative to the western Great Basin. However, these effects cannot account for the extremely high lake levels during the early middle Pleistocene; rather, these high levels were probably due to a combination of increased

  16. GEOMORPHIC CONTROLS ON MEADOW ECOSYSTEMS IN THE CENTRAL GREAT BASIN

    EPA Science Inventory

    Wet meadows, riparian corridor phreatophyte assemblages, and high-altitude spring-fed aspen meadows comprise a very small percentage of the total landscape of the mountain ranges in the central Great Basin however, they represent important ecological environments. We have used s...

  17. JUNIPER CONTROL AND ASPEN RESTORATION IN THE NORTHERN GREAT BASIN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Western juniper woodlands are rapidly replacing lower elevation (< 2100 m) quaking aspen stands throughout the northern Great Basin. Aspen restoration is important because these communities provide important habitat for wildlife species and contain a high diversity of understory shrubs and herbaceou...

  18. A LANDSCAPE ECOLOGY ANALYSIS OF THE GREAT LAKES BASIN

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) and Natural Resources Canada: Canada Centre for Remote Sensing (CCRS) are conducting a cooperative research landscape ecological study of the Great Lakes Basin. The analyses will include the areas located along the border of the Unit...

  19. A REGIONAL ECOLOGICAL ANALYSIS OF THE GREAT LAKES BASIN

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) and Natural Resources Canada: Canada Centre for Remote Sensing (CCRS) are conducting a cooperative research landscape ecological study of the Great Lakes Basin. The analyses will include the areas located along the border of the Unit...

  20. Post-fire grazing management in the Great Basin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing wildfire size and frequency in the Great Basin call for post-fire grazing management practices that ensure sagebrush steppe communities are productive and resilient to disturbances such as drought and species invasions. We provide guidelines for maintaining productive sagebrush steppe co...

  1. The northern Great Basin: a region of continual change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are many controversies and conflicts surrounding land management in the Great Basin. The conflicts often revolve around the maintenance of native plant and animal communities. This paper outlines some of the historical aspects of plant community change and some of the unanticipated impacts of ...

  2. Rehabilitation and Cheatgrass Suppression Following Great Basin Wildfires

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The occurrence of wildfires in Great Basin environments has become an annual event. The introduction and subsequent invasion of cheatgrass (Bromus tectorum) plays a very large role in the frequency and size of these wildfires. With each passing wildfire season, more and more habitats are converted...

  3. ATMOSPHERIC MERCURY MEASUREMENTS: RECENT OBSERVATION IN THE GREAT LAKES BASIN

    EPA Science Inventory

    In order to characterize ambient levels of vapor phase and particle mercury at source and receptor locations in the Great Lakes Basin, and to diagnose source regions of atmospheric mercury, samples were collected at three locations: llinois Institute of Technology (IIT) in Chicag...

  4. The Great Basin Research and Management Partnership: Facilitating Collaborative Solutions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Great Basin is undergoing major sociological and ecological change as a result of urbanization, changing technology and land use, climate change, limited water resources, altered fire regimes, and invasive species, insects, and disease. Sustaining ecosystems, resources, and human populations of...

  5. GREAT LAKES BASIN LAND-COVER DATA: ISSUES AND OPPORTUNITIES

    EPA Science Inventory

    The US Environmental Protection Agency (EPA) is developing a consistent land-cover (LC) data set for the entire 480,000 km2 Great Lakes Basin (GLB). The acquisition of consistent LC data has proven difficult both within the US and across GLB political boundaries due to disparate...

  6. Revegetation Guidelines for the Great Basin: Considering Invasive Weeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Large portions of the Great Basin become degraded and disturbed every day due to natural and human-induced causes. Some disturbed areas may recover naturally in time, but other areas may never recover naturally because invasive weeds establish quickly and prevent native plants from establishing. I...

  7. Late Quaternary environments and biogeography in the Great Basin

    NASA Astrophysics Data System (ADS)

    Thompson, R. S.; Mead, J. I.

    1982-01-01

    Plant and animal remains found in packrat ( Neotoma spp.) middens and cave fill from the eastern and southern Great Basin region reveal the presence of subalpine conifers and boreal mammals at relatively low elevations during the Late Wisconsin. Limber pine ( Pinus flexilis) and bristlecone pine ( P. longaeva) were important in the late Pleistocene plant communities throughout this region. Spruce ( Picea cf. engelmannii) and common juniper ( Juniperus communis) were present in some of the more northerly localities, and Douglas fir ( Pseudotsuga menziesii) and white fir ( Abies concolor) were present in southern and eastern localities. Single needle pinyon pine ( Pinus monophylla), common across this region today, was apparently not present north of the Sheep Range of southern Nevada during the Late Wisconsin. Pikas ( Ochotona cf. princeps), small boreal mammals present in only a few Great Basin mountain ranges today, were common throughout the region. Heather voles ( Phenacomys cf. intermedius) have been found in two cave fill deposits in Nevada, though they are unknown in the Great Basin today. Limber and bristlecone pines are generally restricted to rocky substrates in modern subalpine habitats in the Great Basin, and this may also have been the case when these plants grew at lower elevations during the Late Wisconsin. Subalpine conifers were present on the rock outcrops sampled by the packrat middens, but shrub communities, perhaps dominated by sagebrush ( Artemisia spp.), may have been present on alluvial valley-bottom substrates. Forested habitats would thus have been isolated habitat islands, as they are today. Boreal small mammals, including pikas and heather voles, were able to colonize the Great Basin mountain ranges during the late Pleistocene. We suggest that these mammals were able to survive in the intervening valley-bottoms under a cool-summer climatic regime, and that continuous forest or woodland corridors were not necessary for migration.

  8. Regional Slip Tendency Analysis of the Great Basin Region

    DOE Data Explorer

    Faulds, James E.

    2013-09-30

    Slip and dilation tendency on the Great Basin fault surfaces (from the USGS Quaternary Fault Database) were calculated using 3DStress (software produced by Southwest Research Institute). Slip and dilation tendency are both unitless ratios of the resolved stresses applied to the fault plane by the measured ambient stress field. - Values range from a maximum of 1 (a fault plane ideally oriented to slip or dilate under ambient stress conditions) to zero (a fault plane with no potential to slip or dilate). - Slip and dilation tendency values were calculated for each fault in the Great Basin. As dip is unknown for many faults in the USGS Quaternary Fault Database, we made these calculations using the dip for each fault that would yield the maximum slip or dilation tendency. As such, these results should be viewed as maximum slip and dilation tendency. - The resulting along‐fault and fault‐to‐fault variation in slip or dilation potential is a proxy for along fault and fault‐to‐fault variation in fluid flow conduit potential. Stress Magnitudes and directions were calculated across the entire Great Basin. Stress field variation within each focus area was approximated based on regional published data and the world stress database (Hickman et al., 2000; Hickman et al., 1998 Robertson‐Tait et al., 2004; Hickman and Davatzes, 2010; Davatzes and Hickman, 2006; Blake and Davatzes 2011; Blake and Davatzes, 2012; Moeck et al., 2010; Moos and Ronne, 2010 and Reinecker et al., 2005). The minimum horizontal stress direction (Shmin) was contoured, and spatial bins with common Shmin directions were calculated. Based on this technique, we subdivided the Great Basin into nine regions (Shmin <070, 070140). Slip and dilation tendency were calculated using 3DStress for the faults within each region using the mean Shmin for the region. Shmin variation throughout Great Basin

  9. Interactive Maps from the Great Basin Center for Geothermal Energy

    DOE Data Explorer

    The Great Basin Center for Geothermal Energy, part of the University of Nevada, Reno, conducts research towards the establishment of geothermal energy as an economically viable energy source within the Great Basin. The Center specializes in collecting and synthesizing geologic, geochemical, geodetic, geophysical, and tectonic data, and using Geographic Information System (GIS) technology to view and analyze this data and to produce favorability maps of geothermal potential. The interactive maps are built with layers of spatial data that are also available as direct file downloads (see DDE00299). The maps allow analysis of these many layers, with various data sets turned on or off, for determining potential areas that would be favorable for geothermal drilling or other activity. They provide information on current exploration projects and leases, Bureau of Land Management land status, and map presentation of each type of scientific spatial data: geothermal, geophysical, geologic, geodetic, groundwater, and geochemical.

  10. Great Basin Integrated Landscape Monitoring Pilot Summary Report

    USGS Publications Warehouse

    Finn, Sean P.; Kitchell, Kate; Baer, Lori Anne; Bedford, David R.; Brooks, Matthew L.; Flint, Alan L.; Flint, Lorraine E.; Matchett, J.R.; Mathie, Amy; Miller, David M.; Pilliod, David S.; Torregrosa, Alicia; Woodward, Andrea

    2010-01-01

    The Great Basin Integrated Landscape Monitoring Pilot project (GBILM) was one of four regional pilots to implement the U.S. Geological Survey (USGS) Science Thrust on Integrated Landscape Monitoring (ILM) whose goal was to observe, understand, and predict landscape change and its implications on natural resources at multiple spatial and temporal scales and address priority natural resource management and policy issues. The Great Basin is undergoing rapid environmental change stemming from interactions among global climate trends, increasing human populations, expanding and accelerating land and water uses, invasive species, and altered fire regimes. GBLIM tested concepts and developed tools to store and analyze monitoring data, understand change at multiple scales, and forecast landscape change. The GBILM endeavored to develop and test a landscape-level monitoring approach in the Great Basin that integrates USGS disciplines, addresses priority management questions, catalogs and uses existing monitoring data, evaluates change at multiple scales, and contributes to development of regional monitoring strategies. GBILM functioned as an integrative team from 2005 to 2010, producing more than 35 science and data management products that addressed pressing ecosystem drivers and resource management agency needs in the region. This report summarizes the approaches and methods of this interdisciplinary effort, identifies and describes the products generated, and provides lessons learned during the project.

  11. INTEGRATING GEOPHYSICS, GEOLOGY, AND HYDROLOGY TO DETERMINE BEDROCK GEOMETRY CONTROLS ON THE ORIGIN OF ISOLATED MEADOW COMPLEXES WITHIN THE CENTRAL GREAT BASIN, NEVADA

    EPA Science Inventory

    Riparian meadow complexes found in mountain ranges of the Central Great Basin physiographic region (western United States) are of interest to researchers as they contain significant biodiversity relative to the surrounding basin areas. These meadow complexes are currently degradi...

  12. Water resources management plan: Great Basin National Park

    SciTech Connect

    Jacobs, R.W.; Flora, M.

    1994-06-01

    The enabling legislation creating Great Basin National Park calls for the National Park Service (NPS) to protect, manage, and administer the park in such manner as to conserve and protect the scenery as well as the natural, geologic, historic, and archaeological resources of the park. NPS policies require that each unit of the National Park System develop and implement a General Management Plan (GMP). This plan is designed to serve as a management action plan to guide park water-related activities over the next 10 to 15 years. This WRMP is complementary to, and consistent with, other existing park management documents, including the GMP (NPS 1993) and Resource Management Plan (in review).

  13. 40 CFR 81.159 - Great Basin Valley Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 17 2011-07-01 2011-07-01 false Great Basin Valley Intrastate Air... Air Quality Control Regions § 81.159 Great Basin Valley Intrastate Air Quality Control Region. The Great Basin Valley Intrastate Air Quality Control Region (California) consists of the territorial...

  14. 40 CFR 81.159 - Great Basin Valley Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Great Basin Valley Intrastate Air... Air Quality Control Regions § 81.159 Great Basin Valley Intrastate Air Quality Control Region. The Great Basin Valley Intrastate Air Quality Control Region (California) consists of the territorial...

  15. Fire rehabilitation effectiveness: a chronosequence approach for the Great Basin

    USGS Publications Warehouse

    Pyke, David A.; Pilliod, David S.; Chambers, Jeanne C.; Brooks, Matthew L.; Grace, James

    2009-01-01

    Federal land management agencies have invested heavily in seeding vegetation for emergency stabilization and rehabilitation (ES&R) of non-forested lands. ES&R projects are implemented to reduce post-fire dominance of non-native annual grasses, minimize probability of recurrent fire, quickly recover lost habitat for sensitive species, and ultimately result in plant communities with desirable characteristics including resistance to invasive species and resilience or ability to recover following disturbance. Land managers lack scientific evidence to verify whether seeding non-forested lands achieves their desired long-term ES&R objectives. The overall objective of our investigation is to determine if ES&R projects increase perennial plant cover, improve community composition, decrease invasive annual plant cover and result in a more desirable fuel structure relative to no treatment following fires while potentially providing habitat for Greater Sage-Grouse, a species of management concern. In addition, we provide the locations and baseline vegetation data for further studies relating to ES&R project impacts. We examined effects of seeding treatments (drill and broadcast) vs. no seeding on biotic and abiotic (bare ground and litter) variables for the dominant climate regimes and ecological types within the Great Basin. We attempted to determine seeding effectiveness to provide desired plant species cover while restricting non-native annual grass cover relative to post-treatment precipitation, post-treatment grazing level and time-since-seeding. Seedings were randomly sampled from all known post-fire seedings that occurred in the four-state area of Idaho, Nevada, Oregon and Utah. Sampling locations were stratified by major land resource area, precipitation, and loam-dominated soils to ensure an adequate spread of locations to provide inference of our findings to similar lands throughout the Great Basin. Nearly 100 sites were located that contained an ES&R project. Of

  16. A Review of Fire Effects on Vegetation and Soils in the Great Basin Region: Response and Ecological Site Characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This review summarizes the state of our knowledge on fire effects on plants and soils in semi-arid ecosystems in the Great Basin Region, including the Columbia River and Snake River basins. It identifies what we know and don’t know and the key components that influence how plants, communities, and ...

  17. Deep permeable fault-controlled helium transport and limited mantle flux in two extensional geothermal systems in the Great Basin, United States

    USGS Publications Warehouse

    Banerjee, Amlan; Person, Mark; Hofstra, Albert; Sweetkind, Donald S.; Cohen, Denis; Sabin, Andrew; Unruh, Jeff; Zyvoloski, George; Gable, Carl W.; Crossey, Laura; Karlstrom, Karl

    2011-01-01

    This study assesses the relative importance of deeply circulating meteoric water and direct mantle fluid inputs on near-surface 3He/4He anomalies reported at the Coso and Beowawe geothermal fields of the western United States. The depth of meteoric fluid circulation is a critical factor that controls the temperature, extent of fluid-rock isotope exchange, and mixing with deeply sourced fluids containing mantle volatiles. The influence of mantle fluid flux on the reported helium anomalies appears to be negligible in both systems. This study illustrates the importance of deeply penetrating permeable fault zones (10-12 to 10-15 m2) in focusing groundwater and mantle volatiles with high 3He/4He ratios to shallow crustal levels. These continental geothermal systems are driven by free convection.

  18. Numerical models of carbonate hosted gold mineralization, Great Basin Nevada

    NASA Astrophysics Data System (ADS)

    Person, M.; Hofstra, A.; Gao, Y.; Sweetkind, D.; Banerjee, A.

    2006-12-01

    The Great Basin, Nevada contains many modern hydrothermal system and world class gold deposits hosted within Paleozoic carbonate rocks. Temperature profiles, fluid inclusion studies, and isotopic evidence suggest that modern geothermal and fossil hydrothermal systems associated with gold mineralization share many common features including the absence of a clear magmatic source, flow restricted to fault zones, and remarkably high temperatures at shallow depth. While the plumbing of these systems is not well understood, geochemical and isotopic data suggest that fluid circulation along fault zones is relatively deep (greater than 5 km) and comprised of relatively unexchanged Pleistocene meteoric water with small (less than 2.5 per mill) shifts from the MWL. Many fossil ore-forming systems were also dominated by meteoric water, but are usually exhibit shifts of 5 to 15 per mill from the MWL. Here we present two-dimensional numerical models to reconstruct the plumbing of modern geothermal and Tertiary hydrothermal systems in the Great Basin. Multiple tracers are used in our models, including O- and C-isotopic compositions of fluids/rocks, silica transport/ precipitation, and temperature anomalies, to constrain the plumbing of these systems. Our results suggest that both fossil hydrothermal and modern geothermal systems were probably driven by natural convection cells associated with localized high basal heating. We conclude that the fault controlled flow systems responsible for the genesis of Carlin gold mineralization and modern geothermal systems had to be transient in nature. Permeability changes within the carbonate reservoir was probably associated with extensional tectonic events.

  19. Structural investigations of Great Basin geothermal fields: Applications and implications

    SciTech Connect

    Faulds, James E; Hinz, Nicholas H.; Coolbaugh, Mark F

    2010-11-01

    Because fractures and faults are commonly the primary pathway for deeply circulating hydrothermal fluids, structural studies are critical to assessing geothermal systems and selecting drilling targets for geothermal wells. Important tools for structural analysis include detailed geologic mapping, kinematic analysis of faults, and estimations of stress orientations. Structural assessments are especially useful for evaluating geothermal fields in the Great Basin of the western USA, where regional extension and transtension combine with high heat flow to generate abundant geothermal activity in regions having little recent volcanic activity. The northwestern Great Basin is one of the most geothermally active areas in the USA. The prolific geothermal activity is probably due to enhanced dilation on N- to NNE-striking normal faults induced by a transfer of NW-directed dextral shear from the Walker Lane to NW-directed extension. Analysis of several geothermal fields suggests that most systems occupy discrete steps in normal fault zones or lie in belts of intersecting, overlapping, and/or terminating faults. Most fields are associated with steeply dipping faults and, in many cases, with Quaternary faults. The structural settings favoring geothermal activity are characterized by subvertical conduits of highly fractured rock along fault zones oriented approximately perpendicular to the WNW-trending least principal stress. Features indicative of these settings that may be helpful in guiding exploration for geothermal resources include major steps in normal faults, interbasinal highs, groups of relatively low discontinuous ridges, and lateral jogs or terminations of mountain ranges.

  20. Evaluating Current and Future Rangeland Health in the Great Basin Ecoregion Using NASA Earth Observing Systems

    NASA Astrophysics Data System (ADS)

    Essoudry, E.; Wilson, K.; Ely, J.; Patadia, N.; Zajic, B.; Torres-Perez, J. L.; Schmidt, C.

    2014-12-01

    The Great Basin ecoregion in the western United States represents one of the last large expanses of wild lands in the nation and is currently facing significant challenges due to human impacts, drought, invasive species encroachment such as cheatgrass, and climate change. Rangelands in the Great Basin are of important ecological and economic significance for the United States; however, 40% of public rangelands fail to meet required health standards set by the Bureau of Land Management (BLM). This project provided a set of assessment tools for researchers and land managers that integrate remotely-sensed and in situ datasets to quantify and mitigate threats to public lands in the Great Basin ecoregion. The study area, which accounts for 20% of the total Great Basin ecoregion, was analyzed using 30 m resolution data from Landsat 8. Present conditions were evaluated from vegetation indices, landscape features, hydrological processes, and atmospheric conditions derived from the remotely-sensed data and validated with available in situ ground survey data, provided by the BLM. Rangeland health metrics were developed and landscape change drivers were identified. Subsequently, projected climate conditions derived from the Coupled Model Intercomparison Project (CMIP5) were used to forecast the impact of changing climatic conditions within the study area according to the RCP4.5 and RCP8.5 projections. These forecasted conditions were used in the Maximum Entropy Model (MaxEnt) to predict areas at risk for rangeland degradation on 30 year intervals for 2040, 2070, and 2100. Finally, vegetation health risk maps were provided to the project partners to aid in future land management decisions in the Great Basin ecoregion. These tools provide a low cost solution to assess landscape conditions, provide partners with a metric to identify potential problematic areas, and mitigate serious threats to the ecosystems.

  1. Collaborations, research, and adaptive management to address nonnative Phragmites australis in the Great Lakes Basin

    USGS Publications Warehouse

    Kowalski, Kurt P.

    2016-01-01

    Phragmites australis, also known as common reed, is a native North American wetland grass that has grown in North America for thousands of years. More recently, a nonnative, invasive variety of Phragmites from Eurasia is rapidly invading wetlands across the continental United States and other parts of North America, where it negatively impacts humans and the environment. U.S. Geological Survey scientists, funded by the Great Lakes Restoration Initiative, are leading innovative efforts to improve management of nonnative Phragmites in the Great Lakes Basin.

  2. 3D Geologic Model of the Southern Great Basin

    NASA Astrophysics Data System (ADS)

    Wagoner, J. L.; Myers, S. C.

    2006-12-01

    We have constructed a regional 3D geologic model of the southern Great Basin, in support of a seismic wave propagation investigation of the 1993 Nonproliferation Experiment (NPE) at the Nevada Test Site (NTS). The model is centered on the NPE and spans longitude -119.5° to -112.6°, latitude 34.5° to 39.8°, and a depth from the surface to 150 km below sea level. Hence, the model includes the southern half of Nevada, as well as parts of eastern California, western Utah, and a portion of northwestern Arizona. The upper crust is constrained by geologic and geophysical studies, and the lower crust and upper mantle are constrained by geophysical studies. The upper crustal geologic units are Quaternary basin fill, Tertiary deposits, pre-Tertiary deposits, intrusive rocks, and calderas. The lower crust and upper mantle are parameterized with 8 layers, including the Moho. Detailed geologic data, including surface maps, borehole data, and geophysical surveys, were used to define the geology at the NTS. Digital geologic outcrop data were available for both Nevada and Arizona, whereas we scanned and hand digitized geologic maps for California and Utah. Published gravity data (2km spacing) were used to determine the thickness of the Cenozoic deposits and constrain the depth of the basins. The free surface is based on a 10m lateral resolution DEM at the NTS and a 90m resolution DEM elsewhere. The gross geophysical structure of the crust and upper mantle is taken from regional surface-wave studies. Variations in crustal thickness are based on receiver function analysis and a compilation of reflection/refraction studies. We used the Earthvision (Dynamic Graphics, Inc.) software to integrate the geologic and geophysical information into a model of x,y,z,p nodes, where p is an integer index representing the geologic unit. For regional seismic simulations we convert this realistic geologic model into elastic parameters. Upper crustal units are treated as seismically homogeneous

  3. Woody riparian vegetation of Great Basin National Park. Interim report

    SciTech Connect

    Douglas, C.L.; Smith, S.D.; Murray, K.J.; Landau, F.H.; Sala, A.

    1994-07-01

    The community composition and population structure of the woody riparian vegetation in Great Basin National Park are described. Community analyses were accomplished by sampling 229 plots placed in a systematic random fashion along elevational gradients of 8 major stream systems (Baker, Big Wash, Lehman, Pine, Pole, Shingle, Snake, and Strawberry Creeks) in the Park using the releve method. Stand demographics were determined for the four dominant tree species in the Park, based on absolute stem counts at 15 sites along 6 major watersheds. Elevational ranges of the dominant tree and shrub species along 8 major streams were determined via transect analysis and systematic reconnaissance efforts. TWINSPAN (two-way indicator analysis) indentified 4 primary species groups and 8 stand groups in the Park. Because of the homogeneity of riparian zones, both presence and abundance of species were important parameters in determining species groups. Although species such as Populus tremuloides (aspen), Abies concolor (white fir) and Rosa woodsii (Woods rose) are very common throughout the Park, they are particularly abundant at higher, upper intermediate, and lower intermediate elevations.

  4. Mid-Holocene drying of the U.S. Great Basin recorded in Nevada speleothems

    NASA Astrophysics Data System (ADS)

    Steponaitis, Elena; Andrews, Alexandra; McGee, David; Quade, Jay; Hsieh, Yu-Te; Broecker, Wallace S.; Shuman, Bryan N.; Burns, Stephen J.; Cheng, Hai

    2015-11-01

    Lake level records point to dramatic changes in Great Basin water balance over the last 25 ka, but the timing and pace of Holocene drying in the region remains poorly documented. Here we present stable isotope and trace metal data from two Lehman Caves, NV speleothems that provide a well-dated record of latest Pleistocene to mid-Holocene hydroclimate in the U.S. Great Basin. Together the stalagmites span the interval between 16.4 ka and 3.8 ka, with a hiatus from 15.0 ka to 12.7 ka. Mg/Ca and δ13C covary throughout the records, consistent with control by the extent of degassing and prior calcite precipitation (PCP); measurements of modern cave and soil waters support PCP as the primary control on drip-water trace-element composition. We therefore interpret Mg/Ca and δ13C as reflecting infiltration rates, with higher values corresponding to drier periods. Both Mg/Ca and δ13C indicate a wet period at the beginning of the record (12.7-8.2 ka) followed by pronounced drying after 8.2 ka. This mid-Holocene drying is consistent with records from around the western United States, including a new compilation of Great Basin lake-level records. The strong temporal correspondence with the collapse of the Laurentide ice sheet over Hudson Bay suggests that this drying may have been triggered by northward movement of the winter storm track as a result of ice sheet retreat. However, we cannot rule out an alternative hypothesis that wet early Holocene conditions are related to equatorial Pacific sea-surface temperature. Regardless, our results suggest that Great Basin water balance in the early Holocene was driven by factors other than orbital changes.

  5. Water-quality assessment of the Great Salt Lake basins, Utah, Idaho, and Wyoming; environmental setting and study design

    USGS Publications Warehouse

    Baskin, Robert L.; Waddell, K.M.; Thiros, S.A.; Giddings, E.M.; Hadley, H.K.; Stephens, D.W.; Gerner, S.J.

    2002-01-01

    The Great Salt Lake Basins, Utah, Idaho, and Wyoming is one of 51 study units in the United States where the status and trends of water quality, and the factors controlling water quality, are being studied by the National Water-Quality Assessment Program of the U.S. Geological Survey. The 14,500-square-mile Great Salt Lake Basins study unit encompasses three major river systems that enter Great Salt Lake: the Bear, the Weber, and the Utah Lake/Jordan River systems. The environmental setting of the study unit includes natural and human-related factors that potentially influence the physical, chemical, and/or biological quality of the surface- and ground-water resources. Surface- and ground-water components of the planned assessment activities are designed to evaluate the sources of natural and human-related factors that affect the water quality in the Great Salt Lake Basins study unit.

  6. Limited extension during peak Tertiary volcanism, Great Basin of Nevada and Utah

    NASA Astrophysics Data System (ADS)

    Best, Myron G.; Christiansen, Eric H.

    1991-07-01

    The relative timing and magnitude of middle Tertiary extension and volcanism in the Great Basin (northern Basin and Range province) of the western United States remain controversial. To constrain the timing, we present 31 stratigraphic sections from the central part of the province, together with data from other studies in the Great Basin. Especially significant in this record of regional paleogeographic and associated tectonic conditions are thick sections of many well-dated ash flow sheets emplaced during the period of the most voluminous, or peak, volcanic activity about 31-20 Ma. From these data we make the following conclusions: (1) Extension prior to the period of peak volcanism was apparently localized. (2) Extension during peak volcanism (the ignimbrite flareup) was minor and in places possibly related to magmatic processes in the shallow crust, rather than to regional tectonic processes. Angular unconformities and interbedded epiclastic deposits within sequences of volcanic rocks from 31 to about 22-20 Ma that would manifest synvolcanic faulting, tilting, and erosion are limited. (3) In the Great Basin as a whole, major extension and peak volcanism correlate poorly in space as well as time. (4) Essentially dip-slip faults cutting the entire conformable volcanic sequence are common in the Great Basin and indicate a widespread episode of extension after peak volcanism. Southward sweeping Tertiary volcanism in the Great Basin reflects migration of the mantle magma supply that powered crustal magma systems. We suspect this migration was related to progressive southward foundering and steepening of dip of a subducting oceanic plate (after an earliest Tertiary near-horizontal configuration beneath the continental lithosphere) and consequent backflow of asthenospheric mantle into the widening wedge between the plates. In the northern Great Basin, where the sweep was rapid, we postulate that relatively small volumes of mantle-derived magma were inserted as dikes

  7. Environmental drivers of cambial phenology in Great Basin bristlecone pine.

    PubMed

    Ziaco, Emanuele; Biondi, Franco; Rossi, Sergio; Deslauriers, Annie

    2016-07-01

    The timing of wood formation is crucial to determine how environmental factors affect tree growth. The long-lived bristlecone pine (Pinus longaeva D. K. Bailey) is a foundation treeline species in the Great Basin of North America reaching stem ages of about 5000 years. We investigated stem cambial phenology and radial size variability to quantify the relative influence of environmental variables on bristlecone pine growth. Repeated cellular measurements and half-hourly dendrometer records were obtained during 2013 and 2014 for two high-elevation stands included in the Nevada Climate-ecohydrological Assessment Network. Daily time series of stem radial variations showed rehydration and expansion starting in late April-early May, prior to the onset of wood formation at breast height. Formation of new xylem started in June and lasted until mid-September. There were no differences in phenological timing between the two stands, or in the air and soil temperature thresholds for the onset of xylogenesis. A multiple logistic regression model highlighted a separate effect of air and soil temperature on xylogenesis, the relevance of which was modulated by the interaction with vapor pressure and soil water content. While air temperature plays a key role in cambial resumption after winter dormancy, soil thermal conditions coupled with snowpack dynamics also influence the onset of wood formation by regulating plant-soil water exchanges. Our results help build a physiological understanding of climate-growth relationships in P. longaeva, the importance of which for dendroclimatic reconstructions can hardly be overstated. In addition, environmental drivers of xylogenesis at the treeline ecotone, by controlling the growth of dominant species, ultimately determine ecosystem responses to climatic change. PMID:26917705

  8. Space use of killdeer at a Great Basin breeding area

    USGS Publications Warehouse

    Plissner, Jonathan H.; Oring, L.W.; Haig, Susan M.

    2000-01-01

    Wetland conservation efforts require knowledge of space use by a diversity of waterbirds. However, determining space use of animals requires intensive monitoring of individual organisms. Often, activity patterns during much of the annual cycle are neglected in analyses of home range and habitat use. From 1995-97, we monitored space use in a population of individually marked killdeer (Charadrius vociferus) that breed, and reside for a number of additional months each year, in the western Great Basin. We used linear distance measures and home range-area estimates, derived by fixed-kernel methods, to examine patterns of space use of adults prior to, during, and following nesting. Overall, killdeer used a local area of approximately 6 ha. Birds remained closer to nests while tending eggs than either before or after nesting, although extensive movements away from the nest were observed during all time periods. Females tended to move farther from nests than did males. Birds nesting farther from water bodies were generally observed at greater distances from nests than those nesting closer to shorelines during all time periods. Twenty-seven percent of individuals were observed greater than 1 km from nest locations, particularly during postnesting periods. During nesting periods, males were less likely to be observed at longer distances from nests than were females. There were no differences in home range size based upon sex, time period, or distance from water. We suggest that home range size may not always accurately measure differences in space use and that multiple measures, including distance from nests, should be considered. Understanding the sedentary nature of killdeer during much of the annual cycle and their intense use of local areas is important for making management decisions. Coupled with data on other shorebird species, this information also has broader implications for management of wetland systems by indicating large scale spatial and habitat requirements

  9. Cheatgrass invasion and woody species encroachment in the Great Basin: benefits of conservation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Great Basin is the largest North American desert covering more than 122.5 million acres. Two of the biggest threats to ecosystem stability and integrity in the Great Basin are invasive annual grasses and expansion of native woody plants. The alteration of native plant communities by these invas...

  10. Restoring the Great Basin Desert, U.S.A.: integrating science, management, and people.

    PubMed

    Pellanti, Mike; Abbey, Bob; Karl, Sherm

    2004-12-01

    The Great Basin Desert lies between the Sierra Nevada Mountains to the west and the Rocky Mountains to the east. Nearly 60% of the area's deserts and mountains (roughly 30 million ha) are managed by the U. S. Department of Interior's Bureau of Land Management. This area is characterized by low annual precipitation, diverse desert plant communities, and local economies that depend on the products (livestock grazing, recreation, mining, etc.) produced by these lands. The ecological and economic stability of the Great Basin is increasingly at risk due to the expansion of fire-prone invasive species and increase in wildfires. To stem this loss of productivity and diversity in the Great Basin, the BLM initiated the "Great Basin Restoration Initiative" in 1999 after nearly 0.7 million ha of the Great Basin burned in wildfires. The objective of the Great Basin Restoration Initiative is to restore plant community diversity and structure by improving resiliency to disturbance and resistance to invasive species over the long-term. To accomplish this objective, a strategic plan has been developed that emphasizes local participation and reliance on appropriate science to ensure that restoration is accomplished in an economical and ecologically appropriate manner. If restoration in the Great Basin is not successful, desertification and the associated loss of economic stability and ecological integrity will continue to threaten the sustainability of natural resources and people in the Great Basin. PMID:15641380

  11. 78 FR 13374 - Notice of Public Meetings: Mojave-Southern Great Basin Resource Advisory Council, Nevada

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-27

    ...: 14X1109] Notice of Public Meetings: Mojave-Southern Great Basin Resource Advisory Council, Nevada AGENCY... U.S. Department of the Interior, Bureau of Land Management (BLM) Mojave- Southern Great Basin... transmission, and desert tortoise. Managers' reports of field office activities will be given at each...

  12. Evidence for upper Great Lakes waters in the Erie Basin until 10. 5 ka

    SciTech Connect

    Tinkler, K.J. . Dept. of Geology) Lewis, C.F.M. ); Anderson, T.W. ); Cameron, G.D.M.

    1992-01-01

    Modern recession at Niagara Falls suggests that Erie basin flow alone produces a narrower gorge with recession reduced by an order of magnitude. Gorge interpretations relate dimensions to stages of Great Lakes evolution. A published date of 9.8 ka, for upper river shells at Whirlpool State Park favors an interpretation implying 3.5 kilometers of gorge were cut in the period 12.5 ka to 10.5 ka at a rate of 1.75 m/a, a value consistent with the pre-twentieth century rate of 1.37--1.52 m/a. Erie basin discharge alone would be insufficient to excavate the length of gorge seen. Stratigraphic studies of offshore sediments in lake Erie north-east of Long Point based on seismic profiles and core samples show evidence of lake level change. Following decline of the post-Whittlesey (< 13 ka) southwestward-draining proglacial lakes in the Erie basin and the establishment of Lake Iroquois at about 12.5 ka water levels fell to a control on the Niagara Peninsula. Glacial meltwater continued to pass through the Erie basin until 10.5 ka. Negative shifts in delta O-18 suggest increased meltwater flow through the Erie basin and increased lake level between 11 ka and 10.5 ka. An erosional unconformity, lag sediments, and a distinct former shoreface suggest that lake level subsequently fell in the Long Point area of eastern Lake Erie to about 30m below present by about 10.5 ka when meltwater runoff from the upper Great Lakes by-passed Erie basin. Both the lake cores and the gorge recession are consistent with a computational model of flow out to the Erie basin. According to the model great Lakes outflow, augmented by inflow from Lake Agassiz between 11 to 10.5 ka, would yield shorelines at the height attributed to Lake Tonawanda (180--182m), the immediate source of the Niagara River.

  13. High Temperature Aquifers Beneath the Great Basin - A New Target for Geothermal Power Production

    NASA Astrophysics Data System (ADS)

    Allis, R. G.; Moore, J.; Hardwick, C.

    2011-12-01

    Most geothermal power production from the Great Basin of the western U.S. is located near extensional faults that allow upflow of geothermal fluids to near-surface. However, improved drilling technologies, and the prospect of rising power prices raises the possibility of economically viable large-scale power production from aquifers beneath high heat flow basins of the Great Basin. Oil and gas exploration wells, and water wells in the Great Basin have proven the existence of laterally extensive, high permeability within Paleozoic carbonates. In the southern Great Basin, regional scale ground water flow towards the Colorado River in these carbonates has depressed the heat flow. However, in general the northern Great Basin has not been flushed by ground water, and the heat flow is about 80 - 100 mW/m2. This equates to gradients of about 30 - 40 οC/km in bedrock formations (e.g. beneath the ranges), and about 55 - 75 οC/km within unconsolidated sediments and shale sequences due to the effects of thermal conductivity. There is the potential for temperatures of 150 - 300 οC at 3 - 5 km depth in basins with thick basin fill, as supported by several oil exploration wells in the eastern Great Basin where the temperatures are > 200 οC at 3 km depth. In addition, several shallow wells near one of these deep wells confirm regionally extensive gradients of >65 οC/km. The results of several thermal gradient wells drilled this Fall will be presented. The critical issue for the geothermal potential is whether there is laterally extensive permeability in the 3 - 5 km depth range. The geologic evidence for near-horizontal Paleozoic formations at depth across much of the Great Basin, some of which are known to have characteristically high permeability, suggests the geothermal resource potential beneath the basins could be significant.

  14. Regional surficial geochemistry of the northern Great Basin

    USGS Publications Warehouse

    Ludington, S.; Folger, H.; Kotlyar, B.; Mossotti, V.G.; Coombs, M.J.; Hildenbrand, T.G.

    2006-01-01

    The regional distribution of arsenic and 20 other elements in stream-sediment samples in northern Nevada and southeastern Oregon was studied in order to gain new insights about the geologic framework and patterns of hydrothermal mineralization in the area. Data were used from 10,261 samples that were originally collected during the National Uranium Resource Evaluation (NURE) Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) program in the 1970s. The data are available as U.S. Geological Survey Open-File Report 02-0227. The data were analyzed using traditional dot maps and interpolation between data points to construct high-resolution raster images, which were correlated with geographic and geologic information using a geographic information system (GIS). Wavelength filters were also used to deconvolute the geochemical images into various textural components, in order to study features with dimensions of a few kilometers to dimensions of hundreds of kilometers. The distribution of arsenic, antimony, gold, and silver is different from distributions of the other elements in that they show a distinctive high background in the southeast part of the area, generally in areas underlain by the pre-Mesozoic craton. Arsenic is an extremely mobile element and can be used to delineate structures that served as conduits for the circulation of metal-bearing fluids. It was used to delineate large crustal structures and is particularly good for delineation of the Battle Mountain-Eureka mineral trend and the Steens lineament, which corresponds to a post-Miocene fault zone. Arsenic distribution patterns also delineated the Black Rock structural boundary, northwest of which the basement apparently consists entirely of Miocene and younger crust. Arsenic is also useful to locate district-sized hydrothermal systems an d clusters of systems. Most important types of hydrothermal mineral deposit in the northern Great Basin appear to be strongly associated with arsenic; this is less

  15. Binational ecological risk assessment of bigheaded carps (Hypophthalmichthys spp.) for the Great Lakes Basin.

    USGS Publications Warehouse

    Cudmore, B.; Mandrak, N.E.; Dettmers, J.; Chapman, D.C.; Kolar, C.S.

    2012-01-01

    Bigheaded carps (Bighead and Silver carps) are considered a potential threat to the Great Lakes basin. A binational ecological risk assessment was conducted to provide scientifically defensible advice for managers and decision-makers in Canada and the United States. This risk assessment looked at the likelihood of arrival, survival, establishment, and spread of bigheaded carps to obtain an overall probability of introduction. Arrival routes assessed were physical connections and human-mediated releases. The risk assessment ranked physical connections (specifically the Chicago Area Waterway System) as the most likely route for arrival into the Great Lakes basin. Results of the risk assessment show that there is enough food and habitat for bigheaded carp survival in the Great Lakes, especially in Lake Erie and productive embayments in the other lakes. Analyses of tributaries around the Canadian Great Lakes and the American waters of Lake Erie indicate that there are many suitable tributaries for bigheaded carp spawning. Should bigheaded carps establish in the Great Lakes, their spread would not likely be limited and several ecological consequences can be expected to occur. These consequences include competition for planktonic food leading to reduced growth rates, recruitment and abundance of planktivores. Subsequently this would lead to reduced stocks of piscivores and abundance of fishes with pelagic, early life stages. Overall risk is highest for lakes Michigan, Huron, and Erie, followed by Lake Ontario then Lake Superior. To avoid the trajectory of the invasion process and prevent or minimize anticipated consequences, it is important to continue to focus efforts on reducing the probability of introduction of these species at either the arrival, survival, establishment, or spread stage (depending on location).

  16. Comparing Measurements, Simulations, and Forecasts of Snow Water Equivalent Across the Great Lakes Basin

    NASA Astrophysics Data System (ADS)

    Bolinger, R. A.; Olheiser, C.; Krumwiede, B.; Gronewold, A.

    2014-12-01

    Basin-scale estimates of the water budget of the North American Great Lakes are based on a geographically broad (and, in some areas, relatively sparse) monitoring network that spans the United States-Canadian international border, and a limited ensemble of models. Of the various components of the Great Lakes water budget, snow water equivalent (and its contribution to runoff) represents one that is estimated by a regional rainfall-runoff simulation model (the NOAA large basin runoff model, or LBRM) and by a data assimilation model (via the NOAA National Operational Hydrological Remote Sensing Center Snow Data Assimilation System). Importantly, both products are employed in regional operational water budget and water level forecasts, including those developed by the US Army Corps of Engineers, the New York Power Authority, and Ontario Power Generation. While these forecasts are periodically evaluated for skill based on a comparison between water level projections and observations, we know of no study that has either compared LBRM simulations of SWE to corresponding NOHRSC estimates, or explored the potential benefits of assimilating NOHRSC estimates into the LBRM and propagating those benefits into water level-based management decisions. To address this gap in research and operational knowledge, we compare simulated and "observed" SWE for select sub-basins in the Great Lakes region. We refer to the NOHRSC-SNODAS product as an "observed" estimate of SWE because it combines airborne and surface measurements with satellite derived snow information and model simulations. Our findings indicate general agreement between LBRM-simulated and observation-based estimates of SWE, particularly with respect to the timing of most individual events and the timing of peak SWE. However, we find discontinuities in the timing and duration of snowmelt, the magnitude of the peak runoff, and the overall cumulative seasonal total runoff. Finally, we propagate these estimates of SWE into

  17. Geothermal GIS coverage of the Great Basin, USA: Defining regional controls and favorable exploration terrains

    USGS Publications Warehouse

    Coolbaugh, M.F.; Sawatzky, D.L.; Oppliger, G.L.; Minor, T.B.; Raines, G.L.; Shevenell, L.; Blewitt, G.; Louie, J.N.

    2003-01-01

    A geographic information system (GIS) of geothermal resources, built last year for the state of Nevada, is being expanded to cover the Great Basin, USA. Data from that GIS is being made available to industry, other researchers, and the public via a web site at the Great Basin Center for Geothermal Energy, Reno, Nevada. That web site features a search engine, supports ArcExplorer?? for on-line map construction, and provides downloadable data layers in several formats. Though data collection continues, preliminary analysis has begun. Contour maps of geothermal temperatures, constructed using geothermometer temperatures calculated from a Great Basin geochemical database compiled by the Geo-Heat Center, reveal distinctive trends and patterns. As expected, magmatic-type and extensional-type geothermal systems have profoundly different associations, with magmatic-type systems following major tectonic boundaries, and extensional-type systems associating with regionally high heat flow, thin crust, active faulting, and high extensional strain rates. As described by earlier researchers, including Rowen and Wetlaufer (1981) and Koenig and McNitt (1983), high-temperature (> 100??C) geothermal systems appear to follow regional northeast trends, most conspicuously including the Humboldt structural zone in Nevada, the "Black Rock-Alvord Desert" trend in Oregon and Nevada, and the "Newcastle-Roosevelt" trend in Utah and Nevada. Weights-of-evidence analyses confirm a preference of high-temperature geothermal systems for young northeast-trending faults, but the distribution of geothermal systems correlates even better with high rates of crustal extension, as measured from global positioning system (GPS) stations in Nevada. A predictive map of geothermal potential based only on areas of high extensional strain rates and high heat flux does an excellent job of regionally predicting the location of most known geothermal systems in Nevada, and may prove useful in identifying blind

  18. Paleogeographic and paleotectonic setting of sedimentary basins in the Sevier thrust belt and hinterland, eastern Great Basin

    SciTech Connect

    Schmitt, J.G. . Dept. of Earth Sciences); Vandervoort, D.S. . Dept. of Geological Sciences); Suydam, J.D. . Dept. of Geology)

    1993-04-01

    The eastern Great Basin contains a sparse record of broadly distributed Cretaceous sedimentary rocks which record: evolution of intermontane basins during development of the Sevier (Sv)contractional orogen and incipient extensional collapse of the elevated Sv hinterland (east-central NV), and complex tectono-sedimentary interactions between frontal thrust belt structures and the western margin of the adjacent foreland basin. Palinspastic restoration of these strata and associated structures to pre-Tertiary extension positions reveals a clearer pictures of Cretaceous basin paleogeography and allows comparison with the Puna/Altiplano plateau and precordillera thrust belt of the Neogene Andean orogen. Two syntectonic stratal assemblages are present in east-central NV. Lower Cretaceous alluvial strata (Newark Canyon Fm) record basin development coeval with emergence of contractional structures in the Sv hinterland. Localized early Cretaceous basins were possibly piggyback immature; periods of open drainage to the to the east and south suggest connection with the nascent Sv foreland basin to the east (Cedar Mountain/Sanpete Fms) prior to major thrust loading in central Utah. Development of hinterland structures is almost recorded by Aptian-Albian foreland basin alluvial deposits in SW Utah (Dakota Fm) and southern Nevada (Willow Tank Fm). Upper Cretaceous to Eocene strata (Sheep Pass Fm) record inception of regionally abundant alluvial-lacustrine basins which developed in response to onset of latest Cretaceous extension and associated collapse of the Sv hinterland. Evolution of the structurally complex western margin of the Sv foreland basin is recorded in Cretaceous through Eocene strata deposited in: piggyback basins which were at times hydrologically connected to the adjacent foreland basins, and thrust-proximal portions of the foreland basin. These proximal areas are characterized by folding and faulting of basin fill and development of intrabasinal unconformities.

  19. Classification and Accuracy Assessment for Coarse Resolution Mapping within the Great Lakes Basin, USA

    EPA Science Inventory

    This study applied a phenology-based land-cover classification approach across the Laurentian Great Lakes Basin (GLB) using time-series data consisting of 23 Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) composite images (250 ...

  20. Prescribed fire in a Great Basin sagebrush ecosystem: Dynamics of soil extractable nitrogen and phosphorus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pinyon and juniper have been expanding into sagebrush (Artemisia tridentata) ecosystems since settlement of the Great Basin around 1860. Herbaceous understory vegetation is eliminated as stand densities increase and the potential for catastrophic fires increases. Prescribed fire is increasingly used...

  1. Monitoring Agricultural Cropping Patterns in the Great Lakes Basin Using MODIS-NDVI Time Series Data

    EPA Science Inventory

    This research examined changes in agricultural cropping patterns across the Great Lakes Basin (GLB) using the Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) data. Specific research objectives were to characterize the distribut...

  2. HYDROLOGY OF CENTRAL GREAT BASIN MEADOW ECOSYSTEMS – EFFECTS OF STREAM INCISION

    EPA Science Inventory

    Riparian wet meadow complexes in the mountains of the central Great Basin are scarce, ecologically important systems that are threatened by stream incision. Our interdisciplinary group has investigated 1) the interrelationships of geomorphology, hydrology, and vegetation; and 2) ...

  3. EVALUATING PERTUBATIONS AND DEVELOPING RESTORATION STRATEGIES FOR INLAND WETLANDS IN THE GREAT LAKES BASIN

    EPA Science Inventory

    Wetland coverage and type distributions vary systematically by ecoregion across the Great Lakes Basin. Land use and subsequent changes in wetland type distributions also vary among ecoregions. Incidence of wetland disturbance varies significantly within ecoregions but tends to i...

  4. Great Basin NV Play Fairway Analysis - Carson Sink

    SciTech Connect

    Jim Faulds

    2015-10-28

    All datasets and products specific to the Carson Sink basin. Includes a packed ArcMap (.mpk), individually zipped shapefiles, and a file geodatabase for the Carson Sink area; a GeoSoft Oasis montaj project containing GM-SYS 2D gravity profiles along the trace of our seismic reflection lines; a 3D model in EarthVision; spreadsheet of links to published maps; and spreadsheets of well data.

  5. Simulation of Heavy Lake-Effect Snowstorms across the Great Lakes Basin by RegCM4

    NASA Astrophysics Data System (ADS)

    Notaro, M.; Zarrin, A.; Vavrus, S. J.; Bennington, V.

    2013-12-01

    A historical simulation (1976-2002) of the Abdus Salam International Centre for Theoretical Physics Regional Climate Model Version 4 (ICTP RegCM4), coupled to a one-dimensional lake model, is validated against observed lake ice cover and snowfall across the Great Lakes Basin. The model reproduces the broad temporal and spatial features of both variables in terms of spatial distribution, seasonal cycle, and interannual variability, including climatological characteristics of lake-effect snowfall, although the simulated ice cover is overly extensive largely due to the absence of lake circulations. A definition is introduced for identifying heavy lake-effect snowstorms in regional climate model output for all grid cells in the Great Lakes Basin, using criteria based on location, wind direction, lake ice cover, and snowfall. Simulated heavy lake-effect snowstorms occur most frequently downwind of the Great Lakes, particularly to the east of Lake Ontario and to the east and south of Lake Superior, and are most frequent in December-January. The mechanism for these events is attributed to an anticyclone over the central United States and related cold air outbreak for areas downwind of Lakes Ontario and Erie, in contrast to a nearby cyclone over the Great Lakes Basin and associated cold front for areas downwind of Lakes Superior, Huron, and Michigan. Projections of mid- and late-21st century lake-effect snowstorms in the Great Lakes Basin will be summarized, based on dynamically downscaled CMIP5 (Coupled Model Intercomparison Project Phase Five) simulations.

  6. Upper Colorado River and Great Basin streamflow and snowpack forecasting using Pacific oceanic-atmospheric variability

    NASA Astrophysics Data System (ADS)

    Oubeidillah, Abdoul A.; Tootle, Glenn A.; Moser, Cody; Piechota, Thomas; Lamb, Kenneth

    2011-11-01

    SummaryWater managers in western U.S., including areas such as the State of Utah, are challenged with managing scarce resources and thus, rely heavily on forecasts to allocate and meet various water demands. The need for improved streamflow and snowpack forecast models in the Upper Colorado River and Great Basin is of the utmost importance. In this research, the use of oceanic and climatic variables as predictors to improve the long lead-time (three to nine months) forecast of streamflow and snowpack was investigated. Singular Value Decomposition (SVD) analysis was used to identify a region of Pacific Ocean SSTs and a region of 500 mbar geopotential height (Z 500) that were teleconnected with streamflow (and snowpack) in Upper Colorado River and Great Basin headwaters. The resulting Pacific Ocean SSTs and Z 500 regions were used to create indices that were then used as predictors in a non-parametric forecasting model. The majority of forecasts resulted in positive statistical skill, which indicated an improvement of the forecast over the climatology or no-skill forecast. The results indicated that derived indices from Pacific Ocean SSTs were better suited for long lead-time (six to nine month) forecasts of streamflow (and snowpack) while the derived indices from Z 500 improved short-lead time (3 month) forecasts. In all, the results of the forecast model indicated that incorporating Pacific oceanic-atmospheric climatic variability in forecast models can lead to improved forecasts for both streamflow and snowpack.

  7. Widespread Late Paleozoic remagnetization of the Great Basin miogeocline: Implications for Basin and Range tectonism

    SciTech Connect

    Geissman, J.W. . Dept. of Earth and Planetary Sciences); Gillett, S.L. . Mackay School of Mines); Bartley, J.M. . Dept. of Geology and Geophysics)

    1992-01-01

    In the eastern and southern Great Basin, heterogeneous, shallow-water miogeocline carbonate rocks give a shallow inclination, south to southeast-directed characteristic magnetization residing in magnetite. The magnetization, found in the Desert Range of southern Nevada, the Egan Range of east-central Nevada, and the House Range of western utah, is interpreted to be secondary. It was acquired after (1) local, soft compaction, because directions of magnetization are not dispersed by macroscopic compaction of stylolites and fine carbonate laminations, of up to 25[degree], wrapping around chert masses, and (2) local karst brecciation, as conglomerate tests are negative. The uniform reversed polarity in addition to the direction of the magnetization is interpreted to suggest a late Paleozoic time of remagnetization, in the Kiaman superchron. The authors interpret the secondary magnetization to be of chemical origin, and speculate that it was acquired in response to cratonward fluid migration initiated by Antler contraction. In the Egan Range, about 4 km of Paleozoic strata have been remagnetized. That this secondary but ancient late Paleozoic magnetization has survived subsequent events is significant for interpreting Mesozoic and Cenozoic processes. First, on a regional scale, the Paleozoic miogeocline never experienced burial temperatures greater than about 300 C during mesozoic contraction. Second, because the secondary magnetization can be referenced to the paleohorizontal, it may prove to be an important passive marker for assessing vertical axis rotation related to, first, Mesozoic thrusting, and, second, Cenozoic extension. This is currently being tested.

  8. Ecological monitoring for assessing the state of the nearshore and open waters of the Great Lakes

    USGS Publications Warehouse

    Neilson, Melanie A.; Painter, D. Scott; Warren, Glenn; Hites, Ronald A.; Basu, Ilora; Weseloh, D.V. Chip; Whittle, D. Michael; Christie, Gavin; Barbiero, Richard; Tuchman, Marc; Johannsson, Ora E.; Nalepa, Thomas F.; Edsall, Thomas A.; Fleischer, Guy; Bronte, Charles; Smith, Stephen B.; Baumann, Paul C.

    2003-01-01

    The Great Lakes Water Quality Agreement stipulates that the Governments of Canada and the United States are responsible for restoring and maintaining the chemical, physical and biological integrity of the waters of the Great Lakes Basin Ecosystem. Due to varying mandates and areas of expertise, monitoring to assess progress towards this objective is conducted by a multitude of Canadian and U.S. federal and provincial/state agencies, in cooperation with academia and regional authorities. This paper highlights selected long-term monitoring programs and discusses a number of documented ecological changes that indicate the present state of the open and nearshore waters of the Great Lakes.

  9. Devonian Great Barrier Reef of Canning basin, Western Australia

    SciTech Connect

    Playford, P.E.

    1980-06-01

    A well-preserved Middle to Upper Devonian barrier-reef belt is exhumed as a series of limestone ranges for 350 km along the northern margin of the Canning basin. The reefs are of international importance for reef research because of the excellence of exposures and the lack of extensive dolomitization or structural deformation. They are also known in the subsurface, where they are regarded as prime objectives for oil exploration. The platforms were built by stromatoporoids, algae, and corals in the Givetian and Frasnian, and by algae in the Famennian. The platform and basin deposits were laid down nearly horizontally, whereas the marginal-slope deposits accumulated on steep depositional slopes. Geopetal fabrics, which quantify depositional and tectonic-compactional dip components, provide paleobathymetric data concerning the reef complexes and their fossil biotas. The reef limestones were subject to strong submarine cementation, resulting in very early porosity destruction, whereas the back-reef deposits of the platform interiors remained largely uncemented and retained most of their primary porosity. Stylolitization and associated compaction were greatest in limestones whose primary porosity was not destroyed by early submarine cementation. Consequently the platform interiors have compacted more than the margins, resulting in the typical concave shape of many platforms. Cementation concomitant with stylolitization destroyed most of the porosity that remained in the limestones after early submarine diagenesis. The most porous rocks now are dolomites having secondary moldic porosity. 27 figures.

  10. Petroleum source rock potential and crude oil correlation in Great Basin

    SciTech Connect

    Poole, F.G.; Claypool, G.E.

    1985-05-01

    Petroleum source beds in the Great Basin region include marine Paleozoic rocks and nonmarine upper Mesozoic and lower Cenozoic rocks. Potential source beds have been identified in continental-rise deposits of the Ordovician Vinini and Devonian Woodruff formations if the eastern part of the Roberts Mountains allochthon (Antler orogene), in central and north-central Nevada; in flysch-trough and prodelta-basin deposits of the Mississippian Chainman Shale and equivalent rocks of the Antler foreland basin, in Nevada and western Utah; and in lake-basin deposits of the Cretaceous Neward Canyon Formation and the Paleogene Sheep Pass and Elko formations and equivalent rocks, in central and eastern Nevada. Oil fields in the Great Basin are located with Neogene-Quaternary basins that formed during neogene basin-range block faulting. Most of the oil shows and crude oils analyzed can be correlated with Mississippian or paleogene source rocks. The Mississippian Chainman Shale is confirmed as the major petroleum source rock, having generated the oil in the Trap Spring, Bacon Flat, and Grant Canyon fields in Railroad Valley and the Blackburn field in Pine Valley. The Paleogene Sheep Pass Formation is the source of the oil in the Eagle Springs field and probably the Current field in Railroad Valley. Oil occurrences in the northern Great Basin are believed to be derived from two or more other Tertiary lacustrine sequences.

  11. Simulation of the Arid Climate of the Southern Great Basin Using a Regional Climate Model.

    NASA Astrophysics Data System (ADS)

    Giorgi, Filippo; Bates, Gary T.; Nieman, Steven J.

    1992-11-01

    As part of the development effort of a regional climate model (RCM)for the southern Great Basin, this paper present savalidation analysis of the climatology generated by a high-resolution RCM driven by observations. The RCM is aversion of the National Center for atmospheric Research-Pennsylvania State University mesoscale model, version 4 (MM4), modified for application to regional climate simulation. Two multiyear simulations, for the periods 1 January 1982 to 31 December 1983 and 1 January 1988 to 25 April 1989, were performed over the western United States with the RCM driven by European Centre for Medium-Range Weather Forecasts analyses of observations. The model resolution is 60 km. This validation analysis is the first phase of a project to produce simulations of future climate scenarios over a region surrounding Yucca Mountain, Nevada, the only location currently being considered as a potential high-level nuclear-waste repository site.Model-produced surface air temperatures and precipitation were compared with observations from five southern Nevada stations located in the vicinity of Yucca Mountain. The seasonal cycles of temperature and precipitation were simulated well. Monthly and seasonal temperature biases were generally negative and largely explained by differences in elevation between the observing stations and the model topography. The model-simulated precipitation captured the extreme dryness of the Great Basin. Average yearly precipitation was generally within 30% of observed and the range of monthly precipitation amounts was the same as in the observations. Precipitation biases were mostly negative in the summer and positive in the winter. The number of simulated daily precipitation events for various precipitation intervals was within factors of 1.5-3.5 of observed. Overall, the model tended to overestimate the number of light precipitation events and underestimate the number of heavy precipitation events. At Yucca Mountain, simulated

  12. Active transtensional intracontinental basins: Walker Lane in the western Great Basin

    USGS Publications Warehouse

    Jayko, Angela S.; Bursik, Marcus

    2012-01-01

    The geometry and dimensions of sedimentary basins within the Walker Lane are a result of Plio-Pleistocene transtensive deformation and partial detachment of the Sierra Nevada crustal block from the North American plate. Distinct morpho-tectonic domains lie within this active transtensive zone. The northeast end of the Walker Lane is partly buried by active volcanism of the southern Cascades, and adjacent basins are filled or poorly developed. To the south, the basin sizes are moderate, 25–45km × 15–10 km, with narrow 8-12km wide mountain ranges mainly oriented N-S to NNE. These basins form subparallel arrays in discrete zones trending about 300° and have documented clockwise rotation. This is succeeded to the south by a releasing stepover domain ∼85-100km wide, where the basins are elongated E-W to ENE, small (∼15-30km long, 5-15km wide), and locally occupied by active volcanic centers. The southernmost part of the Walker Lane is structurally integrated, with high to extreme relief. Adjacent basins are elongate, 50-200km long and ∼5 -20km wide. Variations in transtensive basin orientations in the Walker Lane are largely attributable to variations in strain partitioning. Large basins in the Walker Lane have 2-6km displacement across basin bounding faults with up to 3 km of clastic accumulation based on gravity and drill hole data. The sedimentary deposits of the basins may include interbedded volcanic deposits with bimodal basaltic and rhyolitic associations. The basins may include lacustrine deposits that record a wide range of water chemistry from cold fresh water conditions to saline-evaporative

  13. The Late Quaternary biogeographic histories of some Great Basin mammals (western USA)

    NASA Astrophysics Data System (ADS)

    Grayson, Donald K.

    2006-11-01

    The Great Basin of arid western North America provides one of the most detailed late Pleistocene and Holocene mammal records available for any part of the world, though the record is by far strongest for small mammals. Of the 35 genera of now-extinct North American Pleistocene mammals, 19 are known to have occurred in the Great Basin, a list that is likely to be complete or nearly so. Of these 19, seven can be shown to have survived beyond 12,000 radiocarbon years ago, a proportion similar to that for North America as a whole. Horses, camels, mammoth, and helmeted musk-oxen appear to have been the most abundant of these genera. Pygmy rabbits ( Brachylagus idahoensis), yellow-bellied marmots ( Marmota flaviventris), and bushy-tailed woodrats ( Neotoma cinerea) declined in abundance at the end of the Pleistocene, at about the same time as populations south of their current arid western distributional boundary were extirpated. Subsequent declines occurred during the hot/dry middle Holocene. Pygmy rabbits also declined as modern pinyon-juniper woodlands developed across the Great Basin. The Snake Range of eastern Nevada has seen the late Pleistocene or Holocene extinction of both northern pocket gophers ( Thomomys talpoides) and pikas ( Ochotona princeps). Coupled with the rarity of yellow-bellied marmots here, these histories make the Snake Range a biogeographic oddity. These and other Great Basin mammal histories provide significant insights into the possible responses of Great Basin small mammals to global warming.

  14. Using hydrogeologic data to evaluate geothermal potential in the eastern Great Basin

    USGS Publications Warehouse

    Masbruch, Melissa D.; Heilweil, Victor M.; Brooks, Lynette E.

    2012-01-01

    In support of a larger study to evaluate geothermal resource development of high-permeability stratigraphic units in sedimentary basins, this paper integrates groundwater and thermal data to evaluate heat and fluid flow within the eastern Great Basin. Previously published information from a hydrogeologic framework, a potentiometric-surface map, and groundwater budgets was compared to a surficial heat-flow map. Comparisons between regional groundwater flow patterns and surficial heat flow indicate a strong spatial relation between regional groundwater movement and surficial heat distribution. Combining aquifer geometry and heat-flow maps, a selected group of subareas within the eastern Great Basin are identified that have high surficial heat flow and are underlain by a sequence of thick basin-fill deposits and permeable carbonate aquifers. These regions may have potential for future geothermal resources development.

  15. Metallogeny of the Great Basin: crustal evolution, fluid flow, and ore deposits

    USGS Publications Warehouse

    Hofstra, Albert H.; Wallace, Alan R.

    2006-01-01

    The Great Basin physiographic province in the Western United States contains a diverse assortment of world-class ore deposits. It currently (2006) is the world's second leading producer of gold, contains large silver and base metal (Cu, Zn, Pb, Mo, W) deposits, a variety of other important metallic (Fe, Ni, Be, REE's, Hg, PGE) and industrial mineral (diatomite, barite, perlite, kaolinite, gallium) resources, as well as petroleum and geothermal energy resources. Ore deposits are most numerous and largest in size in linear mineral belts with complex geology. U.S. Geological Survey (USGS) scientists are in the final year of a research project initiated in the fall of 2001 to increase understanding of relations between crustal evolution, fluid flow, and ore deposits in the Great Basin. Because of its substantial past and current mineral production, this region has been the focus of numerous investigations over the past century and is the site of ongoing research by industry, academia, and state agencies. A variety of geoinformatic tools was used to organize, reinterpret, and display, in space and time, the large amounts of geologic, geophysical, geochemical, and hydrologic information deemed pertinent to this problem. This information, in combination with concentrated research on (1) critical aspects of the geologic history, (2) an area in northern Nevada that encompasses the major mineral belts, and (3) important mining districts and deposits, is producing new insights about the interplay between key tectonic events, hydrothermal fluid flow, and ore genesis in mineral belts. The results suggest that the Archean to Holocene history of the Great Basin was punctuated by several tectonic events that caused fluids of different origins (sea water, basinal brine, meteoric water, metamorphic water, magmatic water) to move through the crust. Basement faults reactivated during these events localized deformation, sedimentation, magmatism, and hydrothermal fluid flow in overlying

  16. Collaboration in River Basin Management: The Great Rivers Project

    NASA Astrophysics Data System (ADS)

    Crowther, S.; Vridhachalam, M.; Tomala-Reyes, A.; Guerra, A.; Chu, H.; Eckman, B.

    2008-12-01

    The health of the world's freshwater ecosystems is fundamental to the health of people, plants and animals around the world. The sustainable use of the world's freshwater resources is recognized as one of the most urgent challenges facing society today. An estimated 1.3 billion people currently lack access to safe drinking water, an issue the United Nations specifically includes in its recently published Millennium Development Goals. IBM is collaborating with The Nature Conservancy and the Center for Sustainability and the Global Environment (SAGE) at the University of Wisconsin, Madison to build a Modeling Collaboration Framework and Decision Support System (DSS) designed to help policy makers and a variety of stakeholders (farmers, fish and wildlife managers, hydropower operators, et al.) to assess, come to consensus, and act on land use decisions representing effective compromises between human use and ecosystem preservation/restoration efforts. Initially focused on Brazil's Paraguay-Parana, China's Yangtze, and the Mississippi Basin in the US, the DSS integrates data and models from a wide variety of environmental sectors, including water balance, water quality, carbon balance, crop production, hydropower, and biodiversity. In this presentation we focus on the collaboration aspects of the DSS. The DSS is an open environment tool that allows scientists, policy makers, politicians, land owners, and anyone who desires to take ownership of their actions in support of the environment to work together to that end. The DSS supports a range of features that empower such a community to collaboratively work together. Supported collaboration mediums include peer reviews, live chat, static comments, and Web 2.0 functionality such as tagging. In addition, we are building a 3-D virtual world component which will allow users to experience and share system results, first-hand. Models and simulation results may be annotated with free-text comments and tags, whether unique or

  17. Accelerator-mass spectrometer (AMS) radiocarbon dating of Pleistocene lake sediments in the Great Basin

    USGS Publications Warehouse

    Thompson, R.S.; Toolin, L.J.; Forester, R.M.; Spencer, R.J.

    1990-01-01

    Pleistocene lake sediments in the Great Basin typically contain little organic carbon, and thus are difficult to date reliably by conventional radioccarbon methods. Paleoenvironmental data are abundant in these sediments, but are of limited value without adequate age controls. With the advent of accelerator-mass spectrometer (AMS) radiocarbon dating, it is now possible to date these paleolacustrine sediments. AMS dates were obtained on sediment cores from the Bonneville, Franklin, and Lahontan Basins. In the Bonneville Basin, the AMS-based chronology compares well with other chronologies constructed from dated shore-zone features. In the Bonneville and Franklin basins, AMS dates delimit unconformities not apparent by other means. We found that dispersed organic carbon from sediments deposited during relatively freshwater intervals provided apparently reliable AMS radiocarbon dates. Carbonate microfossils from the Lahontan Basin also produced results that appear reasonable, while bulk carbonate yielded erroneous results. ?? 1990.

  18. Great basin paleoenvironmental studies project; Technical progress report first quarter (year 2), June--August 1994

    SciTech Connect

    1994-10-01

    The paleobiotic and geomorphic records are being examined for the local and regional impact of past climates to assess Yucca Mountain`s suitability as a high-level nuclear waste repository. The project includes botanical, faunal, and geomorphic components that will be integrated to accomplish this goal Progress reports are presented for: Paleobotenical studies in the Great Basin; Paleofaunas studies in the Great Basin; Geomorphology studies in the Great Basin; and Transportation. The goal of the transportation project is to compare the results from three models (FESWMS-2DH, DAMBRK, and FLO-2D) that have been suggested as appropriate for evaluating flood flows on alluvial fans with the results obtained from the traditional one-dimensional, stochastic model used in previous research performed by DRI for the Yucca Mountain Project.

  19. The Origin of Basin of Great Lakes in Western Mongolia: Glaciated Super Valley, Not Super Flooding

    NASA Astrophysics Data System (ADS)

    Khukhuudei, Ulambadrakh; Otgonbayar, Orolzodmaa

    2015-04-01

    Research for morphology, its origin of the Basin of Great Lakes in Western Mongolia, is few and far between, particularly, any in recent years. The origin of the morphology of the basin presents a new study, combining previous study materials, their results and interpreting the digital photos. Also the main bases of theory is Pleistocene Last Glacial Maximum distribution. Many scholars have proven that global glaciation covered many areas of the Northern Hemisphere during the Pleistocene era. This global glaciation occurred in the northwest part of Mongolia to Mongolian Altay, Khangay and Khuvsgul mountain range. At the same time, the present appearance of basin that developed inheriting since the Mesozoic era, forms by global glaciation. The morphology of Basin of Great Lakes is super trough or glaciated super valley. At current day, "knock and lochan" topography (scoured region) and rock drumlins lie in the central part of the basin. Huge meltwater from this glaciation formed Shargasub-basin as a super kettle hole by erosion and overflowed water from it formed pluvial basins or big lakes in the Lake Valley.

  20. Great Basin semi-arid woodland dynamics during the late quaternary

    SciTech Connect

    Wigand, P.E.; Hemphill, M.L.; Sharpe, S.E.

    1995-09-01

    Semi-arid woodlands have dominated the middle elevations of Great Basin mountain ranges during the Holocene where subalpine woodlands prevailed during the Pleistocene. Ancient woodrat middens, and in a few cases pollen records indicate in the late Pleistocene and early Holocene woodland history lowered elevation of subalpine woodland species. After a middle Holocene retrenchment at elevations in excess of 500 meters above today, Juniper-dominated semi-arid woodland reached its late Holocene maximum areal extent during the Neoglacial (2 to 4 ka). These records, along with others indicate contracting semi-arid woodland after the Neoglacial about 1.9 ka. Desert shrub community expansion coupled with increased precariousness of wetland areas in the southern Great Basin between 1.9 and 1.5 ka coincide with shrinking wet-lands in the west-central and northern Great Basin. Coincident greater grass abundance in northern Great Basin sagebrush steppe, reaching its maximum between 1.5 and 1.2 ka, corresponds to dramatic increases in bison remains in the archaeological sites of the northern Intermontane West. Pollen and woodrat midden records indicate that this drought ended about 1.5 ka. Succeeding ameliorating conditions resulted in the sudden northward and downward expansion of pinon into areas that had been dominated by juniper during the Neoglacial. Maximum areal extent of pinon dominated semi-arid woodland in west-central Nevada was centered at 1.2 ka. This followed by 100 years the shift in dominance from juniper to pinon in southern Nevada semi-arid woodlands. Great Basin woodlands suffered from renewed severe droughts between .5 to .6 ka. Effectively wetter conditions during the {open_quotes}Little Ice Age{close_quotes} resulted in re-expansion of semi-arid woodland. Activities related to European settlement in the Great Basin have modified prehistoric factors or imposed new ones that are affecting woodland response to climate.

  1. Upper Colorado River and Great Basin Streamflow and Snowpack Forecasting using Pacific Oceanic-Atmospheric Variability

    NASA Astrophysics Data System (ADS)

    Aziz, O. A.; Tootle, G. A.; Moser, C.; Piechota, T. C.; Lamb, K. W.; Kao, S.

    2011-12-01

    Water managers in western U.S., including areas such as the State of Utah, are challenged with managing scarce resources and thus, rely heavily on forecasts to allocate and meet various water demands. The need for improved streamflow and snowpack forecast models in the Upper Colorado River and Great Basin is of the utmost importance. In this research, the use of oceanic and climatic variables as predictors to improve the long lead-time (three to nine months) forecast of streamflow and snowpack was investigated. Singular Value Decomposition (SVD) analysis was used to identify a region of Pacific Ocean SSTs and a region of 500 mbar geopotential height (Z500) that were teleconnected with streamflow (and snowpack) in Upper Colorado River and Great Basin headwaters. The resulting Pacific Ocean SSTs and Z500 regions were used to create indices that were then used as predictors in a non-parametric forecasting model. The majority of forecasts resulted in positive statistical skill, which indicates an improvement over the climatology or no-skill forecast (i.e., ranking of events using the Weibull distribution). The results indicated that derived indices from Pacific Ocean SSTs were better suited for long lead-time (six to nine month) forecasts of streamflow (and snowpack) while the derived indices from Z500 improved short-lead time (3 month) forecasts. In all, the results of the forecast model indicated that incorporating Pacific oceanic-atmospheric climatic variability in forecast models can lead to improved forecasts for both streamflow and snowpack. This method will be applied and tested at several selected hydropower projects in the study area, and some preliminary results will be shown.

  2. Pennsylvanian-Permian tectonism in the Great Basin: The Dry Mountain trough and related basins

    SciTech Connect

    Snyder, W.S.; Spinosa, C.; Gallegos, D.M. )

    1991-02-01

    Pennsylvanian-Permian tectonism affected the continental margin of western North America from the Yukon to the Mojave Desert. Specific signatures of this tectonism include local angular unconformities, regional disconformities, renewed outpouring of clastic debris from a reactivated Antler and related highlands, and development of deeper water basins with anoxic sediments deposited below wave base. The basins formed include Ishbel trough (Canada), the Wood River basin (Idaho), Cassia basin, Ferguson trough, Dry Mountain trough (all Nevada), and unnamed basins in Death Valley-Mojave Desert region. The Dry Mountain trough (DMT) was initiated during early Wolfcampian and received up to 1,200 m of sediment by the late Leonardian. The lower contact is a regional unconformity with the Ely Limestone, or locally with the Diamond Peak or Vinini formations. Thus, following a period of localized regional uplift that destroyed the Ely basin, portions of the uplifted and exposed shelf subsided creating the Dry Mountain trough. Evidence suggesting a tectonic origin for the DMT includes (1) high subsidence rates (60-140 m/m.y.); (2) renewed influx of coarse clastic debris from the Antler highlands: (3) possible pre-Early Permian folding, thrusting, and tilting within the highlands; and (4) differential subsidence within the Dry Mountain trough, suggesting the existence of independent fault blocks.

  3. Effects on environment and agriculture of geothermal wastewater and boron pollution in great Menderes basin.

    PubMed

    Koç, Cengiz

    2007-02-01

    Boron toxicity is an important disorder that can be limit plant growth on soils of arid and semi arid environments through the world. High concentrations of Boron may occur naturally in the soil or in groundwater, or be added to the soil from mining, fertilizers, or irrigation water. Off all the potential resources, irrigation water is the most important contributor to high levels of soil boron, boron is often found in high concentrations in association with saline soil and saline well water. Although of considerable agronomic importance, our understanding of Boron toxicity is rather fragment and limited. In this study, Boron content of Great Menderes River and Basin was researched. Great Menderes Basin is one of the consequence basins having agricultural potential, aspect of water and soil resources in Turkey. Great Menderes River, water resource of the basin was to be polluted by geothermal wastewater and thermal springs including Boron element. Great Menderes Basin has abundant geothermal water resources which contain high amounts of Boron and these ground water are brought to surface and used for various purposes such as power generation, heating or thermal spring and than discharged to Great Menderes River. In order to prevent Boron pollution and hence unproductively in soils, it is necessary not to discharged water with Boron to irrigation water. According to results, it was obtained that Boron content of River was as high in particular Upper Basin where there was a ground thermal water reservoir. Boron has been accumulated more than plant requirement in this area irrigated by this water. Boron content of River was relatively low in rainy months and irrigation season while it was high in dry season. Boron concentration in the River was to decrease from upstream to downstream. If it is no taken measure presently, about 130,000 ha irrigation areas which was constructed irrigation scheme in the Great Menderes basin will expose the Boron pollution and salinity

  4. Basins of attraction for chimera states

    NASA Astrophysics Data System (ADS)

    Martens, Erik A.; Panaggio, Mark J.; Abrams, Daniel M.

    2016-02-01

    Chimera states—curious symmetry-broken states in systems of identical coupled oscillators—typically occur only for certain initial conditions. Here we analyze their basins of attraction in a simple system comprised of two populations. Using perturbative analysis and numerical simulation we evaluate asymptotic states and associated destination maps, and demonstrate that basins form a complex twisting structure in phase space. Understanding the basins’ precise nature may help in the development of control methods to switch between chimera patterns, with possible technological and neural system applications.

  5. The Role of Credit in Native Adaptation to the Great Basin Ranching Economy.

    ERIC Educational Resources Information Center

    Knack, Martha C.

    1987-01-01

    Examines Nevada rancher's account books to explain details of relationship between Great Basin Indian laborers and White employers during the late 19th century. Describes Indians' work, pay rates, purchases, seasonal food availability, and credit arrangements. Examines Indians' social, economic lives and their incorporation into debt/wage system.…

  6. THE GREAT LAKES BASIN LANDSCAPE ECOLOGY METRIC DATA BROWSER (BETA V1.0)

    EPA Science Inventory

    The principal focus of this project is the mapping and interpretation of landscape scale (i.e., broad scale) ecological metrics among hydrologic units and within 1 km, 5 km, and 10 km regions of coastal land in the Great Lakes Basin (GLB). Much is still unknown about the ecologic...

  7. BIRD SPECIES ASSEMBLAGES AS INDICATORS OF BIOLOGICAL INTEGRITY IN GREAT BASIN RANGELAND

    EPA Science Inventory

    The study evaluates the potential for bird species assemblages to serve as indicators of biological integrity of rangelands in the Great Basin in much the same way that fish and invertebrate assemblages have been used as indicators in aquatic environments. Our approach was to ide...

  8. A Trial Virtual Library: Renovation and Innovation at Great Basin College.

    ERIC Educational Resources Information Center

    Karr, Juanita

    2000-01-01

    Describes how librarians coped in temporary quarters in a warehouse and with a drastically reduced circulating and reference collection when Great Basin College's library closed temporarily due to renovation. Discusses how the experience led to innovations in the integration of electronic databases into the renovated library. (VWC)

  9. Assessing the Accuracy of MODIS-NDVI Derived Land-Cover Across the Great Lakes Basin

    EPA Science Inventory

    This research describes the accuracy assessment process for a land-cover dataset developed for the Great Lakes Basin (GLB). This land-cover dataset was developed from the 2007 MODIS Normalized Difference Vegetation Index (NDVI) 16-day composite (MOD13Q) 250 m time-series data. Tr...

  10. Revegetation potential of Great Basin native annuals and perennial grasses: Does facilitation occur?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Revegetation of degraded Great Basin rangelands is a challenging task. In an already unforgiving environment the addition of exotic invasive annual weeds, such as cheatgrass (Bromus tectorum) have added to this challenge. Increasing interest in plant facilitation research has suggested using nati...

  11. MANAGING AND RESTORING UPLAND RIPARIAN MEADOWS IN THE CENTRAL GREAT BASIN

    EPA Science Inventory

    Riparian meadow ecosystems in upland watersheds are of local and regional importance in the Great Basin. Covering only 1-3% of the total land area, these ecosystems contain a disproportionally large percentage of the region's biodiversity. Stream incision, due to natural and anth...

  12. Monitoring Agricultural Cropping Patterns across the Laurentian Great Lakes Basin Using MODIS-NDVI Data

    EPA Science Inventory

    The Moderate Resolution Imaging Spectrometer (MODIS) Normalized Difference Vegetation Index (NDVI) 16-day composite data product (MOD12Q) was used to develop annual cropland and crop-specific map products (corn, soybeans, and wheat) for the Laurentian Great Lakes Basin (GLB). Th...

  13. Response of conifer-encroached shrublands in the Great Basin to prescribed fire and mechanical treatments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In response to the recent expansion of piñon and juniper woodlands into sagebrush steppe communities in the northern Great Basin region, numerous conifer removal projects have been implemented at sites having a wide range of environmental conditions. Response has varied from successful restoration t...

  14. AN INTERDISCIPLINARY APPROACH TO RIPARIAN MEADOW CHARACTERIZATION AND PRIORITIZATION, CENTRAL GREAT BASIN

    EPA Science Inventory

    The Great Basin Ecosystem Management Research group has described the hydrological, geophysical, and geomorphic conditions that lead to the formation and maintenance of riparian meadows of central Nevada. Previous work on these systems has focused on understanding a few study mea...

  15. Mapping Cropland and Major Crop Types Across the Great Lakes Basin Using MODIS-NDVI Data

    EPA Science Inventory

    This research evaluated the potential for using the MODIS Normalized Difference Vegetation Index (NDVI) 16-day composite (MOD13Q) 250-m time-series data to develop a cropland mapping capability throughout the 480 000 km2 Great Lakes Basin (GLB). Cropland mapping was conducted usi...

  16. Hydrologic impacts of woodland encroachment and tree removal in Great Basin sagebrush steppe

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extensive woodland expansion in the Great Basin has generated concern regarding the ecological impacts of tree encroachment on sagebrush (Artemisia spp.) rangelands. This study used rainfall and concentrated flow experiments and measures of vegetation, ground cover, and soils at three sites to inve...

  17. Evaluating mountain meadow groundwater response to pinyon-juniper and temperature in a great basin watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Expansion of deeply-rooted Pinyon-Juniper (PJ) has altered water partitioning and reduced water availability to discharging meadows. Research highlights the development and application of GSFLOW to a semi-arid, snow-dominated watershed in the Great Basin to evaluate PJ and temperature controls on mo...

  18. Two-million-year record of deuterium depletion in great basin ground waters

    USGS Publications Warehouse

    Winograd, I.J.; Szabo, B. J.; Coplen, T.B.; Riggs, A.C.; Kolesar, Peter T.

    1985-01-01

    Fluid inclusions in uranium series-dated calcitic veins from the southern Great Basin record a reduction of 40 per mil in the deuterium content of groundwater recharge during the Pleistocene. This variation is tentatively attributed to major uplift of the Sierra Nevada Range and the Transverse Ranges during this epoch with attendant increasing orographic depletion of deuterium from inlandbound Pacific storms.

  19. Challenges and limitations to native species restoration in the Great Basin, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Great Basin of the western USA is an arid region characterized by high spatial and temporal variability. The region experienced high levels of ecological disturbance during the early period of Euro-American settlement, especially from about 1870 to 1935. The principal plant communities of the ...

  20. Great Basin paleoenvironmental studies project; Technical progress report: First quarter (January--August 1993)

    SciTech Connect

    1993-12-31

    Project goals, project tasks, progress on tasks, and problems encountered are described and discussed for each of the studies that make up the Great Basin Paleoenvironmental Studies Project for Yucca Mountain. These studies are: Paleobotany, Paleofauna, Geomorphology, and Transportation. Budget summaries are also given for each of the studies and for the overall project.

  1. GEOMORPHIC AND HYDROGEOLOGICAL CONTROLS ON THE DISTRIBUTION OF WET MEADOWS IN THE CENTRAL GREAT BASIN

    EPA Science Inventory

    The Great Basin is an arid landscape dominated by dryland vegetation such as big sage and xeric grasses. Meadow complexes occur in mountain drainages and consist of discrete parcels of land up to several hectares in area that are characterized by high water tables and that primar...

  2. Magma genesis during early stages of lithospheric extension: Great Basin of western North America

    SciTech Connect

    Leeman, W.P.; Harry, D.L. . Dept. of Geology Geophysics)

    1993-04-01

    Models for extension-related magmatism based on decompression melting of asthenosphere mantle are in conflict with geological and geochemical observations in the Great Basin. First, assuming a dry'' peridotite source, a substantial lag time (ca. 20 Ma) between onset of extension and first manifestations of magmatism is predicted, whereas magmatism was syn-extensional over a large part of the eastern Great Basin. Second, a gradual increase in magmatic intensity with time is predicted, whereas the observed pattern is characterized by voluminous early volcanism and diminishing melt production with time. Third, the models predict initially deep magma production ([approximately] 80 km) followed by progressive shoaling of the magma production zone. In contrast, compositions of the magmas suggest significant involvement of shallower lithospheric sources (incl. crust) in the earliest magmas, and dominance of deeper asthenospheric sources only in the latest Cenozoic, particularly in the southern portion of the Great Basin -- i.e. a duality of mantle sources. The authors suggest that melting of mafic lithologies within lithospheric mantle is physically plausible and can account for many aspects of early extensional magmatism. Only after lithospheric stretching nears [approximately] 100% does asthenospheric mantle become a dominant source of Great Basin basaltic magmas. There is no need to invoke a plume heat source. This model is tested by comparing the thermo-mechanical behavior of extending lithosphere with phase equilibria results for mafic compositions.

  3. PRECIPITATION TIMING ALTERS SOIL C STORAGE IN A GREAT BASIN SHRUB-STEPPE ECOSYSTEM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Predictions of precipitation responses to global warming vary in timing, magnitude and inter-annual variability. Most research investigating impacts of precipitation timing have focused on plant responses but little is known concerning soil C responses. In a Great Basin shrub-steppe ecosystem, we qu...

  4. GROUND WATER/SURFACE WATER INTERACTIONS IN A GREAT BASIN WET MEADOW ECOSYSTEM

    EPA Science Inventory

    Riparian corridors within upland watersheds of the Great Basin locally contain wet meadow ecosystems that support much of the region's biodiversity. Plant communities in these riparian and wet meadow ecosystems can be highly dependent on the depth to and fluctuations in the water...

  5. 75 FR 4582 - Mojave-Southern Great Basin Resource Advisory Council Meetings, Nevada

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-28

    ... Rock Canyon National Conservation Area fees. March 24-25, BLM Southern Nevada District Office, 4701 N...: 14X1109] Mojave-Southern Great Basin Resource Advisory Council Meetings, Nevada AGENCY: Bureau of Land...), will hold three meetings in Nevada in fiscal year 2010. All meetings are open to the public. DATES...

  6. The importance of persistent monitoring of great basin rangeland rehabilitation efforts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It has long been acknowledged the drastic change in fire cycles of the Great Basin rangelands due to cheatgrass (Bromus tectorum) invasion (Billings 1952, Young and Evans 1974, Wright 1980). An annual grass fire cycle now exists with return intervals less than 5 years compared to historical 60 to110...

  7. HYDROLOGIC AND GEOMORPHIC CONTROLS ON RIPARIAN ECOSYSTEMS IN THE GREAT BASIN OF CENTRAL NEVADA

    EPA Science Inventory

    Understanding surface and ground water flow system interactions is key to maintaining and restoring riparian and wet meadow ecosystems, especially in the Great Basin of central Nevada where they support the majority of the region's biodiversity. To better understand these intera...

  8. Hydrologic vulnerability of Great Basin sagebrush-steppe following pinyon and juniper encroachment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extensive woodland encroachment into sagebrush-steppe has altered vegetation structure and hydrologic function of Great Basin rangelands. Tree encroachment elicits a coarse vegetation pattern of tree dominance and spatially well-connected sparsely-covered intercanopy area. These changes coarsen th...

  9. The influence of woodland encroachment on runoff and erosion in sagebrush steppe systems, Great Basin, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pinyon and juniper woodlands have expanded 10 to 30% in the past 30 years and now occupy nearly 20 million hectares of sagebrush shrub steppe in the Great Basin Region and Colorado Plateau, USA. The conversion of sagebrush steppe to pinyon and juniper woodlands has been linked to changes in plant co...

  10. 76 FR 11506 - Notice of Public Meetings: Northeastern Great Basin Resource Advisory Council, Nevada

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-02

    ... Bureau of Land Management [LLNV912000 L16400000.PH0000 LXSS006F0000 261A; 11-08807; MO 4500020151; TAS: 14X1109] Notice of Public Meetings: Northeastern Great Basin Resource Advisory Council, Nevada AGENCY: Bureau of Land Management, Interior. ACTION: Notice of public meetings. SUMMARY: In accordance with...

  11. Assessing Sediment Yield for Selected Watersheds in the Laurentian Great Lakes Basin Under Future Agricultural Scenarios

    EPA Science Inventory

    In the Laurentian Great Lakes Basin (GLB), corn acreage has been expanding since 2005 in response to high demand for corn as an ethanol feedstock. This study integrated remote sensing-derived products and the Soil and Water Assessment Tool (SWAT) withing a GIS modeling environme...

  12. Hydrochemical evolution and groundwater flow processes in the Galilee and Eromanga basins, Great Artesian Basin, Australia: a multivariate statistical approach.

    PubMed

    Moya, Claudio E; Raiber, Matthias; Taulis, Mauricio; Cox, Malcolm E

    2015-03-01

    The Galilee and Eromanga basins are sub-basins of the Great Artesian Basin (GAB). In this study, a multivariate statistical approach (hierarchical cluster analysis, principal component analysis and factor analysis) is carried out to identify hydrochemical patterns and assess the processes that control hydrochemical evolution within key aquifers of the GAB in these basins. The results of the hydrochemical assessment are integrated into a 3D geological model (previously developed) to support the analysis of spatial patterns of hydrochemistry, and to identify the hydrochemical and hydrological processes that control hydrochemical variability. In this area of the GAB, the hydrochemical evolution of groundwater is dominated by evapotranspiration near the recharge area resulting in a dominance of the Na-Cl water types. This is shown conceptually using two selected cross-sections which represent discrete groundwater flow paths from the recharge areas to the deeper parts of the basins. With increasing distance from the recharge area, a shift towards a dominance of carbonate (e.g. Na-HCO3 water type) has been observed. The assessment of hydrochemical changes along groundwater flow paths highlights how aquifers are separated in some areas, and how mixing between groundwater from different aquifers occurs elsewhere controlled by geological structures, including between GAB aquifers and coal bearing strata of the Galilee Basin. The results of this study suggest that distinct hydrochemical differences can be observed within the previously defined Early Cretaceous-Jurassic aquifer sequence of the GAB. A revision of the two previously recognised hydrochemical sequences is being proposed, resulting in three hydrochemical sequences based on systematic differences in hydrochemistry, salinity and dominant hydrochemical processes. The integrated approach presented in this study which combines different complementary multivariate statistical techniques with a detailed assessment of the

  13. Space use, migratory connectivity, and population segregation among Willets breeding in the western Great Basin

    USGS Publications Warehouse

    Haig, S.M.; Oring, L.W.; Sanzenbacher, P.M.; Taft, O.W.

    2002-01-01

    Western Willets (Catoptrophorus semipalmatus inornatus) were banded (n = 146 breeding adults and chicks) and radio-marked (n = 68 adults) at three western Great Basin wetland complexes to determine inter- and intraseasonal space use and movement patterns (primarily in 1998 and 1999). Birds were then tracked to overwintering sites where migratory connectivity and local movements were documented. Willets arrived synchronously at breeding sites during mid-April and spent less than 12 weeks in the Great Basin. There were no movements to other sites in the Great Basin during the breeding or postbreeding season. However, most breeding birds moved locally on a daily basis from upland nest sites to wetland foraging sites. The mean distance breeding birds were detected from nests did not differ between sexes or between members of a pair, although these distances were greater among postbreeding than breeding birds. Home-range estimates did not differ significantly between paired males and females during breeding or postbreeding. However, female home ranges were larger following breeding than during breeding. Shortly after chicks fledged, adult Willets left the Great Basin for locations primarily at coastal and estuarine sites in the San Francisco Bay area. Limited data revealed little among-site movements once Willets arrived at the coast, and birds appeared to be site faithful in subsequent winters. Winter sites of western Great Basin Willets differed from those used by birds from other areas in the subspecies' range, suggesting another subspecies or distinct population segment may exist. This study illustrates the importance of understanding movements and space use throughout the annual cycle in conservation planning.

  14. Space use, migratory connectivity, and population segregation among willets breeding in the western Great Basin

    USGS Publications Warehouse

    Haig, Susan M.; Oring, L.W.; Sanzenbacher, Peter; Taft, Oriane W.

    2002-01-01

    Western Willets (Catoptrophorus semipalmatus inornatus) were banded (n = 146 breeding adults and chicks) and radio-marked (n = 68 adults) at three western Great Basin wetland complexes to determine inter- and intraseasonal space use and movement patterns (primarily in 1998 and 1999). Birds were then tracked to overwintering sites where migratory connectivity and local movements were documented. Willets arrived synchronously at breeding sites during mid-April and spent less than 12 weeks in the Great Basin. There were no movements to other sites in the Great Basin during the breeding or postbreeding season. However, most breeding birds moved locally on a daily basis from upland nest sites to wetland foraging sites. The mean distance breeding birds were detected from nests did not differ between sexes or between members of a pair, although these distances were greater among postbreeding than breeding birds. Home-range estimates did not differ significantly between paired males and females during breeding or postbreeding. However, female home ranges were larger following breeding than during breeding. Shortly after chicks fledged, adult Willets left the Great Basin for locations primarily at coastal and estuarine sites in the San Francisco Bay area. Limited data revealed little among-site movements once Willets arrived at the coast, and birds appeared to be site faithful in subsequent winters. Winter sites of western Great Basin Willets differed from those used by birds from other areas in the subspecies' range, suggesting another subspecies or distinct population segment may exist. This study illustrates the importance of understanding movements and space use throughout the annual cycle in conservation planning.

  15. Trends in Pan Evaporation and Application of the Complimentary Relationship of Evaporation in the Great Basin, USA

    NASA Astrophysics Data System (ADS)

    Huntington, J. L.; Caldwell, T.; Naranjo, R.; Burak, S.; Tyler, S.

    2007-12-01

    Evaluating available water resources in the Great Basin is an increasing topic of discussion by several local, State, and Federal government agencies due to proposals for water importation into areas of rapid population growth. In estimating a water budget for a particular flow system in the Great Basin, groundwater evapotranspiration (ET) from phreatophyte vegetation is often the most important as it is the only water budget component that can be estimated with some certainty, opposed to mountain block recharge and interbasin subsurface flow. Bouchet's complimentary relationship of evaporation has drawn noteworthy attention in recent years, not only because of its use in explaining observed changes in the hydrologic cycle, but also for its use in predicting ET using readily available meteorological data. The objective of this presentation is twofold: 1) to discuss pan evaporation trends in the Great Basin, and 2) discuss results from the application of the complimentary relationship for predicting evapotranspiration from phreatophyte shrubs when compared to measured ET at several U.S. Geological Survey eddy correlation and Bowen ratio sites. Initial findings indicate a decrease of pan evaporation in Death Valley, CA, the lowest, hottest, and driest location in North America, an opposite trend from analysis of several other sites in the Great Basin that indicate an increase of pan evaporation. It is believed that these opposing trends are likely the result of local water availability surrounding the pan, and or data quality. The application of a symmetric complimentary relationship indicate satisfactory results when compared to measured evapotranspiration, however, during the hottest months of the year the predicted ET over estimates the measured. Further investigation of micrometeorological data suggests that an asymmetric complimentary relationship between potential and actual ET exists, and when taken into account, improves the predictions markedly.

  16. Pacific basin-driven climate variability in the Great Basin of western North America over the past two millennia

    NASA Astrophysics Data System (ADS)

    Lachniet, M. S.; Asmerom, Y.; Polyak, V. J.; Pribyl, P. E.

    2013-12-01

    The origins of decadal- to centennial-scale atmospheric circulation dynamics in the Great Basin of western North America (GB) remain poorly understood because of a lack of high-resolution and absolutely-dated isotopic records extending beyond the instrumental record. Here we show a new high resolution oxygen stable isotopic time-series (501 measurement with ~4.2 yr resolution), anchored by 10 uranium series dates, from a GB stalagmite (LC-1) collected from the high-altitude (2400 m) alpine Leviathan Cave of Nevada that spans the last 2120 years. The δ18O values show pronounced variations of about 2‰ over the past two millennia. We interpret the δ18O record as a proxy for the latitude and temperature of winter source moisture reaching the Great Basin. The δ18O time-series is strongly correlated (r = 0.57) to decadal-scale variability in the tree ring-based index of the Pacific North American (PNA) pattern since 1725 CE. The PNA teleconnection drives variations in the moisture source of winter precipitation reaching the Great Basin: low-δ18O moisture is associated with a higher latitude moisture source and vice versa for high-δ18O moisture. Although the δ18O primarily reflects Pacific-driven changes in the latitude of moisture sources reaching the Great Basin, we also observe a strong positive correlation between 10-yr running averages of δ13C and the PNA index (r = 0.63). Given that δ13C values in soil carbonates in the Great Basin are inversely correlated with effective moisture, our data suggest that the positive PNA is associated with drier than normal winter conditions, and vice versa. The record shows lowest δ18O and δ13C values during the 1930s pluvial, in the late 13th century, in the 11th century, and in the 4th-5th century. Highest δ18O and δ13C values occur in the modern, from 1500-1850 CE, and from 500-900 CE. We do not observe a unique δ18O change over the past two centuries associated with global anthropogenic temperature rise. However, a

  17. Compilation of watershed models for tributaries to the Great Lakes, United States, as of 2010, and identification of watersheds for future modeling for the Great Lakes Restoration Initiative

    USGS Publications Warehouse

    Coon, William F.; Murphy, Elizabeth A.; Soong, David T.; Sharpe, Jennifer B.

    2011-01-01

    As part of the Great Lakes Restoration Initiative (GLRI) during 2009–10, the U.S. Geological Survey (USGS) compiled a list of existing watershed models that had been created for tributaries within the United States that drain to the Great Lakes. Established Federal programs that are overseen by the National Oceanic and Atmospheric Administration (NOAA) and the U.S. Army Corps of Engineers (USACE) are responsible for most of the existing watershed models for specific tributaries. The NOAA Great Lakes Environmental Research Laboratory (GLERL) uses the Large Basin Runoff Model to provide data for the management of water levels in the Great Lakes by estimating United States and Canadian inflows to the Great Lakes from 121 large watersheds. GLERL also simulates streamflows in 34 U.S. watersheds by a grid-based model, the Distributed Large Basin Runoff Model. The NOAA National Weather Service uses the Sacramento Soil Moisture Accounting model to predict flows at river forecast sites. The USACE created or funded the creation of models for at least 30 tributaries to the Great Lakes to better understand sediment erosion, transport, and aggradation processes that affect Federal navigation channels and harbors. Many of the USACE hydrologic models have been coupled with hydrodynamic and sediment-transport models that simulate the processes in the stream and harbor near the mouth of the modeled tributary. Some models either have been applied or have the capability of being applied across the entire Great Lakes Basin; they are (1) the SPAtially Referenced Regressions On Watershed attributes (SPARROW) model, which was developed by the USGS; (2) the High Impact Targeting (HIT) and Digital Watershed models, which were developed by the Institute of Water Research at Michigan State University; (3) the Long-Term Hydrologic Impact Assessment (L–THIA) model, which was developed by researchers at Purdue University; and (4) the Water Erosion Prediction Project (WEPP) model, which was

  18. Water Availability and Use Pilot-A multiscale assessment in the U.S. Great Lakes Basin

    USGS Publications Warehouse

    Reeves, Howard W.

    2011-01-01

    Beginning in 2005, water availability and use were assessed for the U.S. part of the Great Lakes Basin through the Great Lakes Basin Pilot of a U.S. Geological Survey (USGS) national assessment of water availability and use. The goals of a national assessment of water availability and use are to clarify our understanding of water-availability status and trends and improve our ability to forecast the balance between water supply and demand for future economic and environmental uses. This report outlines possible approaches for full-scale implementation of such an assessment. As such, the focus of this study was on collecting, compiling, and analyzing a wide variety of data to define the storage and dynamics of water resources and quantify the human demands on water in the Great Lakes region. The study focused on multiple spatial and temporal scales to highlight not only the abundant regional availability of water but also the potential for local shortages or conflicts over water. Regional studies provided a framework for understanding water resources in the basin. Subregional studies directed attention to varied aspects of the water-resources system that would have been difficult to assess for the whole region because of either data limitations or time limitations for the project. The study of local issues and concerns was motivated by regional discussions that led to recent legislative action between the Great Lakes States and regional cooperation with the Canadian Great Lakes Provinces. The multiscale nature of the study findings challenges water-resource managers and the public to think about regional water resources in an integrated way and to understand how future changes to the system-driven by human uses, climate variability, or land-use change-may be accommodated by informed water-resources management.

  19. Teacher Induction Practices in the United States and Great Britain.

    ERIC Educational Resources Information Center

    Zeichner, Kenneth M.

    This paper examines beginning teacher induction programs in both the United States and Great Britain. Descriptions are given of the scope and activities in 11 selected programs in the United States: (1) the NASSP Project; (2) Washington State; (3) Oswego, New York; (4) Hawaii; (5) Wheeling, Illinois; (6) Wilmette, Illinois; (7) New York City; (8)…

  20. The Great Basin Canada goose in southcentral Washington: A 40-year nesting history

    SciTech Connect

    Fitzner, R.E.; Rickard, W.H.; Eberhardt, L.E.; Gray, R.H.

    1991-04-01

    Overall, the nesting population of Great Basin Canada geese (Branta canadensis moffitti) on the Hanford Site in southcentral Washington State is doing well and appears to be increasing. The average annual total nests for the period 1981 through 1990 was 215 nests, which is slightly above the average reported for the period 1950 through 1970. The nesting population has shifted its nucleus from upriver islands (1--10) to the lower river islands (11--20) with over 70% of the present-day nesting occurring on Islands 17, 18, 19, 20. The annual percent-successful nests from 1981 through 1990 was 80%. This is above the 71% reported for 1950 to 1970, but is below the 82% reported for 1971 to 1980. Average annual clutch size for 1981 to 1990 was 6.05, which is above the 1971-to-1980 average of 5.6 and the 1950-to-70 average of 5.5. Next desertions for 1981 to 1990 averaged 8%. This rate is well below the 14% reported for 1950 to 1970. Predators were responsible for an annual predation rate of 9% from 1981 to 1990. This is below the 1950-to-1970 annual average predation rate of 14%. Flooding losses to nests were low during the 1980s, except for 1989 and 1990 when 6% and 9% of the total nests, respectively, were destroyed by flooding. 9 refs., 4 figs., 1 tab.

  1. ERTS-1 evaluation of natural resources management applications in the Great Basin

    NASA Technical Reports Server (NTRS)

    Tueller, P. T.; Lorain, G.

    1973-01-01

    The relatively cloud free weather in the Great Basin has allowed the accumulation of several dates of excellent ERTS-1 imagery. Mountains, valleys, playas, stream courses, canyons, alluvial fans, and other landforms are readily delineated on ERTS-1 imagery, particularly with MSS-5. Each band is useful for identifying and studying one or more natural resource features. For example, crested wheatgrass seedings were most easily identified and measured on MSS-7. Color enhancements simulating CIR were useful for depicting meadow and phreatophytic vegetation along water bodies and stream courses. Work is underway to inventory and monitor wildfire areas by age and successional status. Inventories have been completed on crested wheatgrass seedings over the entire State of Nevada, and inventories of playa surfaces, water surfaces, phreatophytic vegetation, snow cover, meadows, and other features is continuing. Vegetation ecotones are being delineated for vegetation mapping. The pinyon/juniper-northern desert shrub ecotone has been identified with considerable success. Phenology changes can be used to describe vegetation changes for management.

  2. Thermal regime of the Great Basin and its implications for hydrocarbon occurrence

    SciTech Connect

    Sass, J.H.; Williams, C.F.

    1995-06-01

    The Great Basin is a province of high average heat flow (92+-9 mW m{sup -2}), but it contains sub-provinces of both higher and lower heat flow. Higher heat flow (>100 mW m{sup -2}) is characteristic of the north-central Great Basin (the Battle Mountain High, BMH) and several smaller areas along its margins. There is also a large area of lower heat flow (<60 mW m{sup -2}, the Eureka Low, EL) in the south-central portion of the province. There is hydrologic and thermal evidence that the EL is a shallow ({approximately}3 km) hydrologically controlled heat sink associated with interbasin water flow. For example, the temperature profile from a 3.7 km deep hole at Pahute Mesa in the EL indicates low heat flow in the upper 1.5 km and high heat flow in the lowermost kilometer. On the other hand, seismic and magnetic studies suggest that the heat sink in the EL extends to at least mid-crustal depths. Temperatures in the deeper parts of many basins in the BMH are higher than considered favorable for generation or stability of oil. Paradoxically, temperature-gradients as high as 100{degrees}C km{sup -1} and an underlying hydrothermal system are found within the EL in Railroad Valley, the site of the most productive oil-fields in the Great Basin. The heat source driving this hydrothermal system is a combination of local upward flow from the Paleozoic carbonate aquifer and possible thermal input from nearby igneous activity. J. B. Hulen and others have suggested that the Railroad Valley hydrothermal system has enhanced hydrocarbon transport and accelerated maturation. If a hydrothermal system is required for the formation of significant hydrocarbon reservoirs in the EL, then such reservoirs will occur only where groundwater flow in the carbonate aquifer is not removing heat from the basins.

  3. 75 FR 7291 - Northeastern Great Basin Resource Advisory Council Meetings, Nevada

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-18

    ...In accordance with the Federal Land Policy and Management Act (FLPMA) and the Federal Advisory Committee Act of 1972 (FACA), the U.S. Department of the Interior, Bureau of Land Management (BLM) Nevada Northeastern Great Basin Resource Advisory Council (RAC), will hold three meetings in Nevada in fiscal year 2010. All meetings are open to the public. Dates and Times: March 4 at the BLM Elko......

  4. A review of fire effects on vegetation and soils in the Great Basin region: response and ecological site characteristics

    USGS Publications Warehouse

    Miller, Richard F.; Chambers, Jeanne C.; Pyke, David A.; Pierson, Fred B.; Williams, C. Jason

    2013-01-01

    This review synthesizes the state of knowledge on fire effects on vegetation and soils in semi-arid ecosystems in the Great Basin Region, including the central and northern Great Basin and Range, Columbia River Basin, and the Snake River Plain. We summarize available literature related to: (1) the effects of environmental gradients, ecological site, and vegetation characteristics on resilience to disturbance and resistance to invasive species; (2) the effects of fire on individual plant species and communities, biological soil crusts, seed banks, soil nutrients, and hydrology; and (3) the role of fire severity, fire versus fire surrogate treatments, and post-fire grazing in determining ecosystem response. From this, we identify knowledge gaps and present a framework for predicting plant successional trajectories following wild and prescribed fires and fire surrogate treatments. Possibly the three most important ecological site characteristics that influence a site’s resilience (ability of the ecological site to recover from disturbance) and resistance to invasive species are soil temperature/moisture regimes and the composition and structure of vegetation on the ecological site just prior to the disturbance event.

  5. Monitoring species richness and abundance of shorebirds in the western Great Basin

    USGS Publications Warehouse

    Warnock, N.; Haig, Susan M.; Oring, L.W.

    1998-01-01

    Broad-scale avian surveys have been attempted within North America with mixed results. Arid regions, such as the Great Basin, are often poorly sampled because of the vastness of the region, inaccessibility of sites, and few ornithologists. In addition, extreme variability in wetland habitat conditions present special problems for conducting censuses of species inhabiting these areas. We examined these issues in assessing multi-scale shorebird (order: Charadriiformes) censuses conducted in the western Great Basin from 1992-1997. On ground surveys, we recorded 31 species of shorebirds, but were unable to accurately estimate population size. Conversely, on aerial surveys we were able to estimate regional abundance of some shorebirds, but were unable to determine species diversity. Aerial surveys of three large alkali lakes in Oregon (Goose, Summer, and Abert Lakes) revealed > 300,000 shorebirds in one year of this study, of which 67% were American Avocets (Recurvirostra americana) and 30% phalaropes (Phalaropus spp.). These lakes clearly meet Western Hemisphere Shorebird Reserve Network guidelines for designation as important shorebird sites. Based upon simulations of our monitoring effort and the magnitude and variation of numbers of American Avocets, detection of S-10% negative declines in populations of these birds would take a minimum of 7-23 years of comparable effort. We conclude that a combination of ground and aerial surveys must be conducted at multiple sites and years and over a large region to obtain an accurate picture of the diversity, abundance, and trends of shorebirds in the western Great Basin.

  6. Monitoring species richness and abundance of shorebirds in the western Great Basin

    USGS Publications Warehouse

    Warnock, N.; Haig, S.M.; Oring, L.W.

    1998-01-01

    Broad-scale avian surveys have been attempted within North America with mixed results. Arid regions, such as the Great Basin, are often poorly sampled because of the vastness of the region, inacessibilty of sites, and few ornithologist. In addition, extreme variability in wetland habitat conditions present special problems for conducting censuses of species inhabiting these areas. We examined these issues in assessing multi-scale shorebird (order: Charadriiformes) censuses conducted the western Great Basin from 1992-1997. On ground surveys, we recorded 31 species of shorebirds, but were unable to accurately estimate population size. Conversely, on aerial surveys we were able to estimate regional abundance of some shorebirds, but were unable to determined species diversity. Acrial surveys of three large alkali lakcs in Oregon (Goose, Summer, and abert Lakes) revealed > 300,000 shorebirds in one year of this study, of which 67% were American Avocets (Recurvirostra americana) and 30% phalaropes (Phalaropus spp.). These lakes clearly meet Western Hemisphere Shorebird Reserve Network guidelines for designation as important shorebirds sites. Based upon simulations of our monitoring effort and the magnitude and variation of numbers of American Avocets, detection of 5-10% negative declines in population of these birds would take a minimum of 7-23 years comparable effort. We conclude that a combination of ground and aerial surveys must be conducted at multiple sites and years and over a large region to obtain an accurate picture of the diversity, abundance, and trends of shorebirds in the western Great Basin.

  7. Models of Seismic Velocity and Anisotropy For the Great Basin, Nevada

    NASA Astrophysics Data System (ADS)

    Beghein, C.

    2010-12-01

    The Great Basin, which lies in the northern Basin and Range Province in the western United States, has a complex deformation history and is currently characterized by significant crustal extension. The region is marked by a semi-circular shear-wave splitting pattern around a weak azimuthal anisotropy zone in central Nevada. This observation led to various interpretations, including the presence of an upwelling, toroidal mantle flow around a slab, and lithospheric drip. Recent research, however, showed that a similar signal of anisotropy can be found in Rayleigh wave phase velocity maps at periods of 16 s and 18 s around a region of locally reduced phase velocities (Beghein, et al., EPSL, 2010). Since surface waves at these periods mostly sample the crust, this suggests that at least part of the observed shear-wave splitting pattern has a crustal origin. In the present study, we employ a forward modeling approach to model the three-dimensional (3-D) variations in shear-wave velocities and azimuthal anisotropy in this area. We first use a fully non-linear forward modeling approach based on the Neighbourhood Algorithm (Sambridge, 1999) to model the isotropic velocity variations. This method enables us to quantitatively assess parameter trade-offs and uncertainties. We use prior constraints for the Moho depth based on receiver function results (Miller and Levander, 2009), but we allow it vary by up to 3%. Our results display uniform S-wave velocities of 3.6 km/s in the crust with a standard deviation of ~0.3 km/s. We also find the presence of a mantle lid of ~45 km thickness, with S-wave velocities up to 4.9 km/s (+/- 0.2 km/s). The posterior Moho depth roughly follows the prior model, and we find that the locally thicker crust located in the southwestern part of the region is sufficient to explain the reduction in phase velocities seen at short periods at the center of the circular anisotropy pattern. Velocities are lower down to at least 100 km depth with Vs=3.9 km

  8. Children's Home Environments in Great Britain and the United States

    ERIC Educational Resources Information Center

    Campbell, Lori Ann; Parcel, Toby L.

    2010-01-01

    This study analyzes the effects of human, social, and financial capital on children's home environments in the United States and Great Britain by comparing a sample of 5- to 13-year-old children from the United States with a similar sample from Britain. In both countries, the authors find weaker home environments for boys, minority children, and…

  9. Basin-scale simulation of current and potential climate changed hydrologic conditions in the Lake Michigan Basin, United States

    USGS Publications Warehouse

    Christiansen, Daniel E.; Walker, John F.; Hunt, Randall J.

    2014-01-01

    The Great Lakes Restoration Initiative (GLRI) is the largest public investment in the Great Lakes in two decades. A task force of 11 Federal agencies developed an action plan to implement the initiative. The U.S. Department of the Interior was one of the 11 agencies that entered into an interagency agreement with the U.S. Environmental Protection Agency as part of the GLRI to complete scientific projects throughout the Great Lakes basin. The U.S. Geological Survey, a bureau within the Department of the Interior, is involved in the GLRI to provide scientific support to management decisions as well as measure progress of the Great Lakes basin restoration efforts. This report presents basin-scale simulated current and forecast climatic and hydrologic conditions in the Lake Michigan Basin. The forecasts were obtained by constructing and calibrating a Precipitation-Runoff Modeling System (PRMS) model of the Lake Michigan Basin; the PRMS model was calibrated using the parameter estimation and uncertainty analysis (PEST) software suite. The calibrated model was used to evaluate potential responses to climate change by using four simulated carbon emission scenarios from eight general circulation models released by the World Climate Research Programme’s Coupled Model Intercomparison Project phase 3. Statistically downscaled datasets of these scenarios were used to project hydrologic response for the Lake Michigan Basin. In general, most of the observation sites in the Lake Michigan Basin indicated slight increases in annual streamflow in response to future climate change scenarios. Monthly streamflows indicated a general shift from the current (2014) winter-storage/snowmelt-pulse system to a system with a more equally distributed hydrograph throughout the year. Simulated soil moisture within the basin illustrates that conditions within the basin are also expected to change on a monthly timescale. One effect of increasing air temperature as a result of the changing

  10. Using Seismic Refraction to Assess the Crustal Thickness of the Great Basin and Sierra Nevada

    NASA Astrophysics Data System (ADS)

    Heimgartner, M. N.; Louie, J. N.; Scott, J. B.; Thelen, W.; Pullammanappallil, S.; Lopez, C. T.; Coolbaugh, M. F.

    2006-12-01

    In order to assess the crustal thickness of the Great Basin in poorly constrained areas, we have completed three long-range seismic refraction experiments: the 2002 Northern Walker Lane (NWL) transect, extending from central Nevada to the eastern Sierras; the 2004 Idaho-Nevada-California (INC) experiment, running from central Nevada into Fresno, California; and the 2005 Northern-Nevada-Utah transect (NNUT), stretching from central Nevada through eastern Utah. Our refraction experiments will contribute toward a more accurate crustal model for the northern Great Basin where little previous seismic refraction control exists. The INC and NNUT experiments used a dense spacing of 400 portable seismographs and 4.5-Hz geophones. The instruments were able to record events ranging from large mine blasts to small local earthquakes. Our instruments sensed blast first arrivals out to distances of approximately 400 km. We obtained 99% data recovery and clear first arrivals across the Sierra Nevada and the northern Great Basin regions. From our INC transect, we observe an unexpectedly deep crustal root beneath the northern Sierra Nevada range (>50 km down to a Moho velocity of 7.8 km/s). From the NWL experiment, we observe anomalously thin crust over a limited region approximately 100 km wide, near Battle Mountain, NV, with a crustal thickness of 19-23 km and a southern extent limited by the INC transect. This area of thin crust correlates with regional gravity data. Our NNUT refraction experiment will better constrain crustal thickness and provide insight into the crustal-scale tectonics of the northeastern Great Basin, including the Wasatch Front and eastern Utah. These experiments are a successful demonstration that crustal refraction profiles can be obtained using mine blasts and a dense array of portable seismographs. Costly refraction shots were not needed to find crustal thicknesses, where mine blasts could be recorded. In addition, local earthquakes (approximately M2

  11. Populations at risk: conservation genetics of kangaroo mice (Microdipodops) of the Great Basin Desert

    PubMed Central

    Andersen, John J; Portnoy, David S; Hafner, John C; Light, Jessica E

    2013-01-01

    Abstract The Great Basin Desert of western North America has experienced frequent habitat alterations due to a complex biogeographic history and recent anthropogenic impacts, with the more recent alterations likely resulting in the decline of native fauna and flora. Dark (Microdipodops megacephalus) and pallid (M. pallidus) kangaroo mice are ecological specialists found within the Great Basin Desert and are potentially ideal organisms for assessing ecosystem health and inferring the biogeographic history of this vulnerable region. Herein, newly acquired nuclear-encoded microsatellite loci were utilized to assess patterns of variation within and among spatially discrete groups of kangaroo mice and to evaluate gene flow, demographic trends, and genetic integrity. Results confirm that there are at least three genetically distinct units within M. megacephalus and two such units within M. pallidus. The three units of M. megacephalus appear to have different demographic histories, with effectively no gene flow among them since their divergence. Similarly, the two units of M. pallidus also appear to have experienced different demographic histories, with effectively no gene exchange. Contemporary effective population sizes of all groups within Microdipodops appear to be low (<500), suggesting that each genetic lineage may have difficulty coping with changing environmental pressures and hence may be at risk of extirpation. Results of this study indicate that each Microdipodops group should be recognized, and therefore managed, as a separate unit in an effort to conserve these highly specialized taxa that contribute to the diversity of the Great Basin Desert ecosystem. The Great Basin Desert of western North America has experienced frequent habitat alterations due to a complex biogeographic history and recent anthropogenic impacts, with the more recent alterations likely resulting in the decline of native fauna and flora. Herein, newly acquired nuclear

  12. Populations at risk: conservation genetics of kangaroo mice (Microdipodops) of the Great Basin Desert.

    PubMed

    Andersen, John J; Portnoy, David S; Hafner, John C; Light, Jessica E

    2013-08-01

    The Great Basin Desert of western North America has experienced frequent habitat alterations due to a complex biogeographic history and recent anthropogenic impacts, with the more recent alterations likely resulting in the decline of native fauna and flora. Dark (Microdipodops megacephalus) and pallid (M. pallidus) kangaroo mice are ecological specialists found within the Great Basin Desert and are potentially ideal organisms for assessing ecosystem health and inferring the biogeographic history of this vulnerable region. Herein, newly acquired nuclear-encoded microsatellite loci were utilized to assess patterns of variation within and among spatially discrete groups of kangaroo mice and to evaluate gene flow, demographic trends, and genetic integrity. Results confirm that there are at least three genetically distinct units within M. megacephalus and two such units within M. pallidus. The three units of M. megacephalus appear to have different demographic histories, with effectively no gene flow among them since their divergence. Similarly, the two units of M. pallidus also appear to have experienced different demographic histories, with effectively no gene exchange. Contemporary effective population sizes of all groups within Microdipodops appear to be low (<500), suggesting that each genetic lineage may have difficulty coping with changing environmental pressures and hence may be at risk of extirpation. Results of this study indicate that each Microdipodops group should be recognized, and therefore managed, as a separate unit in an effort to conserve these highly specialized taxa that contribute to the diversity of the Great Basin Desert ecosystem. The Great Basin Desert of western North America has experienced frequent habitat alterations due to a complex biogeographic history and recent anthropogenic impacts, with the more recent alterations likely resulting in the decline of native fauna and flora. Herein, newly acquired nuclear-encoded microsatellite

  13. Regionalization of hydrologic response in the Great Lakes basin: Considerations of temporal scales of analysis

    NASA Astrophysics Data System (ADS)

    Kult, Jonathan M.; Fry, Lauren M.; Gronewold, Andrew D.; Choi, Woonsup

    2014-11-01

    Methods for predicting streamflow in areas with limited or nonexistent measures of hydrologic response commonly rely on regionalization techniques, where knowledge pertaining to gauged watersheds is transferred to ungauged watersheds. Hydrologic response indices have frequently been employed in contemporary regionalization research related to predictions in ungauged basins. In this study, we developed regionalization models using multiple linear regression and regression tree analysis to derive relationships between hydrologic response and watershed physical characteristics for 163 watersheds in the Great Lakes basin. These models provide an empirical means for simulating runoff in ungauged basins at a monthly time step without implementation of a rainfall-runoff model. For the dependent variable in these regression models, we used monthly runoff ratio as the indicator of hydrologic response and defined it at two temporal scales: (1) treating all monthly runoff ratios as individual observations, and (2) using the mean of these monthly runoff ratios for each watershed as a representative observation. Application of the models to 62 validation watersheds throughout the Great Lakes basin indicated that model simulations were far more sensitive to the temporal characterization of hydrologic response than to the type of regression technique employed, and that models conditioned on individual monthly runoff ratios (rather than long term mean values) performed better. This finding is important in light of the increased usage of hydrologic response indices in recent regionalization studies. Models using individual observations for the dependent variable generally simulated monthly runoff with reasonable skill in the validation watersheds (median Nash-Sutcliffe efficiency = 0.53, median R2 = 0.66, median magnitude of the deviation of runoff volume = 13%). These results suggest the viability of empirical approaches to simulate runoff in ungauged basins. This finding is

  14. Low Elevation Riparian Environments: Warm-Climate Refugia for Conifers in the Great Basin, USA?

    NASA Astrophysics Data System (ADS)

    Millar, C.; Charlet, D. A.; Westfall, R. D.; Delany, D.

    2015-12-01

    The Great Basin, USA, contains hundreds of small to large mountain ranges. Many reach alpine elevations, which are separated from each other by low-elevation basins currently inhospitable to conifer growth. Many of these ranges support montane and subalpine conifer species that have affinities to the Sierra Nevada or Rocky Mountains, and from which these conifers migrated during cool periods of the Pleistocene. Under Holocene climates, the Great Basin geography became a terrestrial island-archipelago, wherein conifer populations are isolated among ranges, and inter-range migration is highly limited. During warm intervals of the Holocene, conifers would be expected to have migrated upslope following favorable conditions, and extirpation would be assumed to result from continued warming. Independent patterns, repeating across multiple species' distributions, however, suggest that refugia were present in these ranges during warm periods, and that low elevation environments below the current main distributions acted as climatic refugia. We hypothesize that cool, narrow, and north-aspect ravines, which during cool climates support persistent or seasonal creeks and deciduous riparian communities, become available as conifer habitat when warming climates desiccate creeks and deplete riparian species. We further speculate that cold-air drainage, reduced solar insolation, lower wind exposure, and higher water tables in these topographic positions support populations of montane and subalpine conifers even during warm climate intervals when high elevations are unfavorable for conifer persistence. On return to cool climates, low elevation refugia become sources for recolonizing higher slopes, and/or continue to persist as relictual populations. We present several lines of evidence supporting this hypothesis, and speculate that low-elevation, extramarginal riparian environments might act as climate refugia for Great Basin conifers in the future as well.

  15. An investigation of historical lake-atmosphere interactions in the Great Lakes Basin

    NASA Astrophysics Data System (ADS)

    Holman, Kathleen Danielle

    The Laurentian Great Lakes are a tremendous freshwater resource, holding approximately 20% of the world's unfrozen freshwater. With a combined surface area of 244,000 km2, the Great Lakes are constantly interacting with the overlying atmosphere through fluxes of heat, moisture, and momentum. In the current study, we explore interactions between the Great Lakes and overlying atmosphere using a combination of observational and modeling tools. Results based on historical observations indicate that over-lake precipitation from the Lake Superior watershed is associated with transient Rossby waves during each month of the year. Further analysis indicates the origin and path of these waves change with the background flow. During summer and early fall, the Pacific jet is relatively sharp and acts as a waveguide, such that Rossby wave trains traversing the Great Lakes region do not follow a great-circle path. While the atmosphere primarily dictates hydrology in the Great Lakes basin, each of the Great Lakes feeds back on the overlying atmosphere, ultimately influencing the local and regional climate. Historical observational and modeling studies support this claim; however, a consistent, long-term analysis of the impacts of the Great Lakes on climate has yet to be executed. In the current analysis, the influence of the Great Lakes on climate is assessed by comparing two decade-long regional climate simulations, with the lakes present or replaced by woodland. Model results indicate the Great Lakes dampen seasonal and daily surface air temperature ranges, alter the strength and track of synoptic systems, and modify atmospheric stability. Additional analysis based on output from the regional climate model indicates that seasonal fluctuations in atmospheric stability over Lake Superior influence the ratio of over-lake to over-land precipitation. Since the current operational technique used to estimate over-lake precipitation does not account for variations in atmospheric

  16. Developing the Late Quaternary Record of Pluvial Lake Clover, Northern Great Basin, U.S.A

    NASA Astrophysics Data System (ADS)

    Laabs, B. J.; Munroe, J. S.

    2009-12-01

    Lake Clover was one of numerous closed-basin pluvial lakes that formed in the northern Great Basin during the Pleistocene. The geomorphic record of the lake includes continuous shoreline ridges and spits at altitudes of as much as 25 m above the modern playa surface. The history of Lake Clover is poorly known compared to those of the larger lakes Lahontan and Bonneville, but can provide a useful framework for understanding regional-scale environmental changes during the latest Pleistocene. Shoreline ridges of Lake Clover are preserved at altitudes of ca. 1729, 1725, 1719, and 1715 m asl, which correspond to intervals when the lake attained a surface area of 788, 726, 618, and 524 km2, respectively. Although the chronology of highstands at these altitudes is still being developed (through radiocarbon and luminescence-dating methods), the morphology and orientations of prominent shoreline features provide clues to regional air-circulation patterns during highstands. The highest shoreline is represented by a gravel ridge that can be traced nearly continuously around the perimeter of the lake basin. The ridge is uniformly developed along shorelines of differing aspect, suggesting that the wind field during the ice-free season was not dominated by a single direction. Along the eastern and western shores of the basin, the lower shorelines are manifested by a similar gravel ridge. However, in other sectors of the basin, features associated with progressively lower shorelines reveal an increasing dominance of northward longshore drift. The most dramatic features correspond with the 1719 m shoreline and include 1) a pronounced V-shaped, northward projecting spit at the southern end of the basin, 2) a 3-km long spit projecting to the north-northwest along the northeastern shoreline, and 3) a tombolo connecting a former island to the northern shore. Together these features suggest that dominant wind directions became more southerly during the ice-free season when the lake

  17. Tectonic and Structural Controls of Geothermal Activity in the Great Basin Region, Western USA

    NASA Astrophysics Data System (ADS)

    Faulds, J. E.; Hinz, N.; Kreemer, C. W.

    2012-12-01

    We are conducting a thorough inventory of structural settings of geothermal systems (>400 total) in the extensional to transtensional Great Basin region of the western USA. Most of the geothermal systems in this region are not related to upper crustal magmatism and thus regional tectonic and local structural controls are the most critical factors controlling the locations of the geothermal activity. A system of NW-striking dextral faults known as the Walker Lane accommodates ~20% of the North American-Pacific plate motion in the western Great Basin and is intimately linked to N- to NNE-striking normal fault systems throughout the region. Overall, geothermal systems are concentrated in areas with the highest strain rates within or proximal to the eastern and western margins of the Great Basin, with the high temperature systems clustering in transtensional areas of highest strain rate in the northwestern Great Basin. Enhanced extension in the northwestern Great Basin probably results from the northwestward termination of the Walker Lane and the concomitant transfer of dextral shear into west-northwest directed extension, thus producing a broad transtensional region. The capacity of geothermal power plants also correlates with strain rates, with the largest (hundreds of megawatts) along the Walker Lane or San Andreas fault system, where strain rates range from 10-100 nanostrain/yr to 1,000 nanostrain/yr, respectively. Lesser systems (tens of megawatts) reside in the Basin and Range (outside the Walker Lane), where local strain rates are typically < 10 nanostrain/yr. Of the 250+ geothermal fields catalogued, step-overs or relay ramps in normal fault zones serve as the most favorable setting, hosting ~32% of the systems. Such areas have multiple, overlapping fault strands, increased fracture density, and thus enhanced permeability. Other common settings include a) intersections between normal faults and strike-slip or oblique-slip faults (27%), where multiple minor

  18. Phreatophytic land-cover map of the northern and central Great Basin Ecoregion: California, Idaho, Nevada, Utah, Oregon, and Wyoming

    USGS Publications Warehouse

    Mathie, Amy M.; Welborn, Toby L.; Susong, David D.; Tumbusch, Mary L.

    2011-01-01

    Increasing water use and changing climate in the Great Basin of the western United States are likely affecting the distribution of phreatophytic vegetation in the region. Phreatophytic plant communities that depend on groundwater are susceptible to natural and anthropogenic changes to hydrologic flow systems. The purpose of this report is to document the methods used to create the accompanying map that delineates areas of the Great Basin that have the greatest potential to support phreatophytic vegetation. Several data sets were used to develop the data displayed on the map, including Shrub Map (a land-cover data set derived from the Regional Gap Analysis Program) and Gap Analysis Program (GAP) data sets for California and Wyoming. In addition, the analysis used the surface landforms from the U.S. Geological Survey (USGS) Global Ecosystems Mapping Project data to delineate regions of the study area based on topographic relief that are most favorable to support phreatophytic vegetation. Using spatial analysis techniques in a GIS, phreatophytic vegetation classes identified within Shrub Map and GAP were selected and compared to the spatial distribution of selected landforms in the study area to delineate areas of phreatophyte vegetation. Results were compared to more detailed studies conducted in selected areas. A general qualitative description of the data and the limitations of the base data determined that these results provide a regional overview but are not intended for localized studies or as a substitute for detailed field analysis. The map is intended as a decision-support aide for land managers to better understand, anticipate, and respond to ecosystem changes in the Great Basin.

  19. Nested Calderas in the Northern Kawich Range, Central Nevada: Termination of the Ignimbrite Flare-up in the Great Basin

    NASA Astrophysics Data System (ADS)

    Honn, D. K.; Smith, E. I.

    2006-05-01

    During the ignimbrite flare-up in the Great Basin of the western United States nearly 500,000 km3 of ash- flow tuff related to caldera collapse was erupted between about 40 and 23 Ma. In the central Great Basin the flare-up ended abruptly at about 23 Ma and major caldera generating eruptions did not occur again for nearly 7 Ma. To test models for the demise of this voluminous igneous event, we studied ash-flow tuffs in the northern Kawich Range, central Nevada that erupted just before the end of the ignimbrite flare-up. Five calderas were discovered in the northern Kawich Range; each filled with intracaldera rhyolite tuffs and caldera collapse breccias. Based on 40Ar / 39Ar dating of sanidine and crosscutting relations, the calderas erupted in the following order from oldest to youngest: Clifford Spring (23.67 ± 0.09 Ma), Tobe Spring (22.77 ± 0.07 Ma), Cow Canyon (22.78 ± 0.07 Ma), Bellehelen (22.87 ± 0.16 Ma), and Warm Springs. Field evidence including the occurrence of older welded tuff clasts in younger collapse breccia deposits indicates that these calderas represent separate events and not a single caldera with piecemeal collapse. The five intracaldera tuffs are chemically and chronologically similar to the widespread Pahranagat Formation (33,000 km2)and the Pyramid Spring tuff. To explain the eruption of at least seven tuffs of very similar chemistry over a short period of time (1.06 m.y), large scale partial melting (>50%) of the lower crust is required. Transfer of heat from the crust to the atmosphere during these eruptions cooled the crust may have resulted in the suppression of the ignimbrite flare-up in the Great Basin at 23 Ma.

  20. Water resources data, Idaho, 2002; Volume 1. Great Basin and Snake River basin above King Hill

    USGS Publications Warehouse

    Brennan, T.S.; Lehmann, A.K.; Campbell, A.M.; O'Dell, I.; Beattie, S.E.

    2003-01-01

    Water resources data for the 2002 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The two volumes of this report contain discharge records for 196 stream-gaging stations and 15 irrigation diversions; stage only records for 5 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 78 stream-gaging stations and partial record sites, 3 lakes sites, and 383 groundwater wells; and water levels for 425 observation network wells and 900 special project wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.

  1. Three-Dimensional Geologic Characterization of a Great Basin Geothermal System: Astor Pass, Nevada

    SciTech Connect

    Mayhew, Brett; Siler, Drew L; Faulds, James E

    2013-09-30

    The Great Basin, western USA, exhibits anomalously high heat flow (~75±5 mWm-2) and active faulting and extension, resulting in ~430 known geothermal systems. Recent studies have shown that steeply dipping normal faults in transtensional pull-aparts are a common structural control of these Great Basin geothermal systems. The Astor Pass blind (no surface expression) geothermal system, Nevada, lies along the boundary between the Basin and Range to the east and the Walker Lane to the west. Across this boundary, strain is transferred from dextral shear in the Walker Lane to west-northwest directed extension in the Basin and Range, resulting in a transtensional setting consisting of both northwest-striking, left-stepping dextral faults and northerly striking normal faults. Previous studies indicate that Astor Pass was controlled by the intersection of a northwest-striking dextral normal fault and north-northwest striking normal-dextral fault bounding the western side of the Terraced Hills. Drilling (to ~1200 m) has revealed fluid temperatures of ~94°C, confirming a blind geothermal system. Expanding upon previous work and employing interpretation of 2D seismic reflection data, additional detailed geologic mapping, and well cuttings analysis, a 3-dimensional geologic model of the Astor Pass geothermal system was constructed. The 3D model indicates a complex interaction/intersection area of three discrete fault zones: a northwest-striking dextral-normal fault, a north-northwest-striking normal-dextral fault, and a north-striking west-dipping normal fault. These two discrete, critically-stressed intersection areas plunge moderately to steeply to the NW-NNW and probably act as conduits for upwelling geothermal fluids.

  2. 3D characterization of a Great Basin geothermal system: Astor Pass, NV

    SciTech Connect

    Siler, Drew L; Brett, Mayhew; Faulds, James E

    2012-12-03

    The Great Basin exhibits both anomalously high heat flow (~75±5 mWm-2) and active faulting and extension resulting in robust geothermal activity. There are ~430 known geothermal systems in the Great Basin, with evidence suggesting that undiscovered blind geothermal systems may actually represent the majority of geothermal activity. These systems employ discrete fault intersection/interaction areas as conduits for geothermal circulation. Recent studies show that steeply dipping normal faults with step-overs, fault intersections, accommodation zones, horse-tailing fault terminations and transtensional pull-aparts are the most prominent structural controls of Great Basin geothermal systems. These fault geometries produce sub-vertical zones of high fault and fracture density that act as fluid flow conduits. Structurally controlled fluid flow conduits are further enhanced when critically stressed with respect to the ambient stress conditions. The Astor Pass blind geothermal system, northwestern Nevada, lies along the boundary between the Basin and Range to the east and the Walker Lane to the west. Along this boundary, strain is transferred from dextral shear in the Walker Lane to west-northwest directed extension in the Basin and Range. As such, the Astor Pass area lies in a transtensional setting consisting of both northwest-striking, left-stepping dextral faults and more northerly striking normal faults. The Astor Pass tufa tower implies the presence of a blind geothermal system. Previous studies suggest that deposition of the Astor Pass tufa was controlled by the intersection of a northwest-striking dextral normal fault and north-northwest striking normal fault. Subsequent drilling (to ~1200 m) has revealed fluid temperatures of ~94°C, confirming the presence of a blind geothermal system at Astor Pass. Expanding upon previous work and employing additional detailed geologic mapping, interpretation of 2D seismic reflection data and analysis of well cuttings, a 3

  3. Late Cenozoic displacement-field partitioning in the western Great Basin

    SciTech Connect

    Oldow, J.S. . Dept. of Geology and Geophysics)

    1993-04-01

    Late Cenozoic (15 Ma to recent) structures in the western Great Basin record a complex history of extension and transcurrent faulting that reflect displacement-field partitioning and migration of a deformation front outward from the center of the province. The location and morphology of late Cenozoic structures were strongly influenced by the pre-Tertiary crustal architecture of western Nevada and eastern California formed during continental rifting and subsequent active margin tectonism. Late Cenozoic displacements are spatially partitioned components of N55[degree]W regional extension. Within the Great Basin, a central domino of uniform extension (N55[degree]W) is bound on the west by a broad northwest-trending zone of transtension, the Walker Lane Belt (WLB). Central domain extension is accommodated by north-northeast half-grabens that initiated in the mid-Miocene in central Nevada and in the Mio-Pliocene in north west Nevada. Transtension in the WLB is characterized by coeval displacements on oblique-slip faults of various orientations and right-slip on northwest transcurrent faults. As in the central domain, the locus of activity migrated westerly with time in the WLB. The present-day extension axis for oblique-slip faults in the western Great Basin changes stepwise from N55[degree]W, to N75[degree]W, to N75[degree]E as the WLB and Sierra Nevada are approached from the east. The change in extension direction is viewed as the product of displacement field partitioning and not as the result of regional stress variation.

  4. Age and paleoclimatic significance of the Stansbury shoreline of Lake Bonneville, Northeastern Great Basin

    USGS Publications Warehouse

    Oviatt, Charles G.; Currey, D.R.; Miller, D.M.

    1990-01-01

    The Stansbury shoreline, one of the conspicuous late Pleistocene shorelines of Lake Bonneville, consists of tufa-cemented gravel and barrier beaches within a vertical zone of about 45 m, the lower limit of which is 70 m above the modern average level of Great Salt Lake. Stratigraphic evidence at a number of localities, including new evidence from Crater Island on the west side of the Great Salt Lake Desert, shows that the Stansbury shoreline formed during the transgressive phase of late Pleistocene Lake bonneville (sometime between about 22,000 and 20,000 yr B.P.). Tufa-cemented gravel and barrier beaches were deposited in the Stansbury shorezone during one or more fluctuations in water level with a maximum total amplitude of 45 m. We refer to the fluctuations as the Stansbury oscillation. The Stansbury oscillation cannot have been caused by basin-hypsometric factors, such as stabilization of lake level at an external overflow threshold or by expansion into an interior subbasin, or by changes in drainage basin size. Therefore, changes in climate must have caused the lake level to reverse its general rise, to drop about 45 m in altitude (reducing its surface area by about 18%, 5000 km2), and later to resume its rise. If the sizes of Great Basin lakes are controlled by the mean position of storm tracks and the jetstream, which as recently postulated may be controlled by the size of the continental ice sheets, the Stansbury oscillation may have been caused by a shift in the jetstream during a major interstade of the Laurentide ice sheet. ?? 1990.

  5. Great Basin paleoenvironmental studies project; Third quarterly technical progress report, December 1993--February 1994

    SciTech Connect

    1994-04-01

    Examination of the paleolithic and geomorphic records to determine the local and regional impact of past climates will advance assessment of Yucca Mountain`s suitability as a high-level nuclear waste repository. The project includes the integration of botanical, faunal, and geomorphic components to accomplish this goal. Paleobotanical studies will reconstruct the response of vegetation to climate change at the community and the organismal levels by integrating data obtained from nearly continuous sediment records of pollen, plant macrofossils, and stable isotopes from fossil woodrat middens. The goal of the paleofaunas study is to construct a history of Great Basin vertebrates, particularly mammals, that will provide empirical evidence of past environmental and climatic conditions within the Great Basin as it is recorded by the animals. Taxonomic composition of archaeological and paleontological faunas from various areas within the Great Basin and morphological change within individual mammalian taxa at specific localities are being investigated to monitor faunal response to changing environmental conditions. The objective of the geomorphology component of the paleoenvironmental program is to document the responses of surficial processes and landforms to the climatic changes documented by studies of packrat middens, pollen, and faunal distributions. The project will focus on: (1) stratigraphic relationships between lake deposits and aeolian or fluvial sediments and landforms; (2) cut and fill sequences in floodplain and river-channel deposits; (3) identification of periods of dune mobility and stability; (4) documentation of episodes of alluvial fan and terrace development and erosion; and (5) correlation of (3) and (4) to climatically driven lake-level fluctuation as revealed by shoreline features such as strandlines and beach ridges. Accomplishments for this period are presented for these studies.

  6. Great Principals at Scale: State & Federal Policy Brief

    ERIC Educational Resources Information Center

    New Leaders, 2014

    2014-01-01

    New Leaders and the George W. Bush Institute's Alliance to Reform Education Leadership (AREL) released a report entitled "Great Principals at Scale: Creating District Conditions that Enable All Principals to Be Effective" in June 2014. This brief summarizes the framework presented in that report and recommends actions that states and the…

  7. Children's Behavior Problems in the United States and Great Britain

    ERIC Educational Resources Information Center

    Parcel, Toby L.; Campbell, Lori Ann; Zhong, Wenxuan

    2012-01-01

    We analyze the effects of family capital on child behavior problems in the United States and Great Britain by comparing a longitudinal survey sample of 5- to 13-year-old children from the 1994 National Longitudinal Survey of Youth (N = 3,864) with a similar sample of children from the 1991 National Child Development Study "British Child" (N =…

  8. The Common Core State Standards and the Great Divide

    ERIC Educational Resources Information Center

    Wiley, Terrence G.; Rolstad, Kellie

    2014-01-01

    This article contextualizes recent developments around issues of language and the new Common Core State Standards (CCSS) in terms of the classic distinction between literates and non-literates in the Great Divide debate. Using a social practices perspective to frame the issues, the authors argue that the CCSS reiterate the debate, and reflect an…

  9. Quantifying cambial activity of high-elevation conifers in the Great Basin, Nevada, USA

    NASA Astrophysics Data System (ADS)

    Ziaco, E.; Biondi, F.; Rossi, S.; Deslauriers, A.

    2013-12-01

    Understanding the physiological mechanisms that control the formation of tree rings provides the necessary biological basis for developing dendroclimatic reconstructions and dendroecological histories. Studies of wood formation in the Great Basin are now being conducted in connection with the Nevada Climate-ecohydrological Assessment Network (NevCAN), a recently established transect of valley-to-mountaintop instrumented stations in the Snake and Sheep Ranges of the Great Basin. Automated sensors record meteorological, soil, and vegetational variables at these sites, providing unique opportunities for ecosystem science, and are being used to investigate the ecological implications of xylogenesis. We present here an initial study based on microcores collected during summer 2013 from mountain and subalpine conifers (including Great Basin bristlecone pine, Pinus longaeva) growing on the west slope of Mt. Washington. Samples were taken from the mountain west (SM; 2810 m elevation) and the subalpine west (SS, 3355 m elevation) NevCAN sites on June 16th and 27th, 2013. The SS site was further subdivided in a high (SSH) and a low (SSL) group of trees, separated by about 10 m in elevation. Microscopic analyses showed the effect of elevation on cambial activity, as annual ring formation was more advanced at the lower (mountain) site compared to the higher (subalpine) one. At all sites cambium size showed little variations between the two sampling dates. The number of xylem cells in the radial enlargement phase decreased between the two sampling dates at the mountain site but increased at the subalpine site, confirming a delayed formation of wood at the higher elevations. Despite relatively high within-site variability, a general trend of increasing number of cells in the lignification phase was found at all sites. Mature cells were present only at the mountain site on June 27th. Spatial differences in the xylem formation process emerged at the species level and, within

  10. Accelerated Geothermal Resource Development in the Great Basin Through Enhanced Public Awareness and Outreach to Shareholders.

    SciTech Connect

    Taranik, James V.; Oppliger, Gary; Sawatsky, Don

    2002-04-10

    The Great Basin Center for Geothermal Energy conducted work encompassing two main tasks. We (1) produced a web-based, stakeholder geothermal information system for Nevada geothermal data relevant to assessing and developing geothermal resources, and (2) we held informational stakeholder workshops (both as part of GeoPowering the West Initiative). The objective of this grant was to conduct workshops and fund database and web development activities. This grant funds salaries for web and database developers and part of the administrative assistant who helps to coordinate and organize workshops, and maintain selected databases.

  11. Constraining the location of the Archean--Proterozoic suture in the Great Basin based on magnetotelluric soundings

    USGS Publications Warehouse

    Rodriguez, Brian D.; Sampson, Jay A.

    2012-01-01

    It is important to understand whether major mining districts in north-central Nevada are underlain by Archean crust, known to contain major orogenic gold deposits, or, alternatively, by accreted crust of the Paleoproterozoic Mojave province. Determining the location and orientation of the Archean-Proterozoic suture zone between the Archean crust and Mojave province is also critical because it may influence subsequent patterns of sedimentation, deformation, magmatism, and hydrothermal activity. In the Great Basin, the attitude of the suture zone is unknown because it is concealed below cover. A regional magnetotelluric sounding profile along the Utah-Nevada State line reveals a deeply penetrating, broad electrical conductor that may be the Archean-Proterozoic suture zone in the northwest corner of Utah. This major crustal conductor's strike direction is northwest, where it broadens to about 80 km wide below about 3-km depth. These results suggest that the southwestern limit of intact Archean crust in this part of the Great Basin is farther north than previously reported. These results also suggest that the major gold belts in north-central Nevada are located over the Paleoproterozoic Mojave province, and the Archean terrain lies northeast in the northwest corner of Utah. Rifted Archean crust segments south and west of the suture suggest that future mineral exploration northeast of current mineral trends may yield additional gold deposits.

  12. Mercury policy in the Great Lakes states: past successes and future opportunities.

    PubMed

    Cain, Alexis; Morgan, Joy Taylor; Brooks, Ned

    2011-10-01

    While mercury (Hg) releases to air and water within the Great Lakes states have declined significantly, concentrations of mercury in fish remain a cause for concern regarding human and ecosystem health in the Great Lakes Basin. This paper assesses the priority that Hg source reduction ought to have in relation to some other environmental concerns, and explores the relative costs of various Hg reduction policies. Long-range transport of atmospheric mercury creates a collective action problem for states, since most of the mercury emitted within any given state deposits outside that state's borders, and since most of the mercury deposited within a state originated outside that state. This paper discusses some of the mechanisms that policy makers in the Great Lakes states employed to get beyond the collective action problem, including: providing an example for others to follow; using cross-jurisdiction cooperation to leverage the benefits of leadership on Hg reduction and control; and, promoting voluntary actions. Recommendations for future opportunities include: focusing reduction efforts on sources with the highest total mass of emissions rather than solely focusing on reduction of local deposition and utilizing all tools available in the clean air and clean water acts. PMID:21861165

  13. Five millennia of paleotemperature from tree-rings in the Great Basin, USA

    NASA Astrophysics Data System (ADS)

    Salzer, Matthew W.; Bunn, Andrew G.; Graham, Nicholas E.; Hughes, Malcolm K.

    2014-03-01

    The instrumental temperature record is of insufficient length to fully express the natural variability of past temperature. High elevation tree-ring widths from Great Basin bristlecone pine ( Pinus longaeva) are a particularly useful proxy to infer temperatures prior to the instrumental record in that the tree-rings are annually dated and extend for millennia. From ring-width measurements integrated with past treeline elevation data we infer decadal- to millennial-scale temperature variability over the past 4,500 years for the Great Basin, USA. We find that twentieth century treeline advances are greater than in at least 4,000 years. There is also evidence for substantial volcanic forcing of climate in the preindustrial record and considerable covariation between high elevation tree-ring widths and temperature estimates from an atmosphere-ocean general circulation model over much of the last millennium. A long-term temperature decline of ~-1.1 °C since the mid-Holocene underlies substantial volcanic forcing of climate in the preindustrial record.

  14. Possible extrinsic controls on the Ordovician radiation: Stratigraphic evidence from the Great Basin, western USA

    SciTech Connect

    Droser, M.L. . Dept. of Earth Sciences); Fortey, R.A. . Dept. of Palaeontology)

    1993-04-01

    The Ordovician radiation has been previously examined by looking at 1/analyses of patterns of diversification within small clades, 2/analyses of large databases to elucidate large-scale paleoecological patterns such as increased tiering and onshore-offshore shifts associated with this radiation. In order to resolve the relationships between these two scales of analysis there is critical need to examine in detail the paleoecology and possible biofacies shifts associated with the Ordovician radiation. The authors have examined the base of the Whiterock Series (Lower-Middle Ordovician) in the Great Basin as it represents one of the most complete records of the Ordovician radiation on the North American continent. Detailed field evidence suggests that the base of the Whiterock does not represent a simple faunal turnover but corresponds with the first occurrences in the region of groups that come to dominate the rest of the Paleozoic. Among the trilobites, this includes the lichides, calymenids, proetides, and phacopides. Similar patterns are found among the dominate Paleozoic bivalve, cephalopod, brachiopod and graptolite clades. Global correlation of this time interval suggests that this pattern of first broad geographic occurrences is not unique to North America. This boundary corresponds with a globally recognized sea level lowstand. In the Great Basin, significant facies shifts are present in shallow and deep water settings. While extrinsic controls are commonly reserved for extinctions, these data suggest that extrinsic factors may have been significant in the timing of the Paleozoic fauna rose to dominance.

  15. Identification of source-sink dynamics in mountain lions of the Great Basin.

    PubMed

    Andreasen, Alyson M; Stewart, Kelley M; Longland, William S; Beckmann, Jon P; Forister, Matthew L

    2012-12-01

    Natural and anthropogenic boundaries have been shown to affect population dynamics and population structure for many species with movement patterns at the landscape level. Understanding population boundaries and movement rates in the field for species that are cryptic and occur at low densities is often extremely difficult and logistically prohibitive; however genetic techniques may offer insights that have previously been unattainable. We analysed thirteen microsatellite loci for 739 mountain lions (Puma concolor) using muscle tissue samples from individuals in the Great Basin throughout Nevada and the Sierra Nevada mountain range to test the hypothesis that heterogeneous hunting pressure results in source-sink dynamics at the landscape scale. We used a combination of non-spatial and spatial model-based Bayesian clustering methods to identify genetic populations. We then used a recently developed Bayesian multilocus genotyping method to estimate asymmetrical rates of contemporary movement between those subpopulations and to identify source and sink populations. We identified two populations at the highest level of genetic structuring with a total of five subpopulations in the Great Basin of Nevada and the Sierra Nevada range. Our results suggest that source-sink dynamics occur at landscape scales for wide-ranging species, such as mountain lions, and that source populations may be those that are under relatively less hunting pressure and that occupy refugia. PMID:22934825

  16. Great Basin paleoenvironmental studies project; Technical progress report: Fourth quarter, March--May, 1994

    SciTech Connect

    1994-07-01

    Examination of the paleoenvironmental and geomorphic records to determine the local and regional impact of past climates will advance the assessment of Yucca Mountain`s suitability as a high-level nuclear waste repository. Paleobotanical studies will reconstruct the response of vegetation to climate change at the community and the organismal levels in order to identify periods of mesic climate at Yucca Mountain and the adjacent region during the last 20,000 to 50,000 years. Constructing a history of Great Basin vertebrates, particularly mammals, will provide empirical evidence of past environmental and climatic conditions within the Great Basin. The objective of the geomorphology component of the program is to document the responses of surficial processes and landforms to the climatic changes documented by studies of packrat middens, pollens, and faunal distributions. The goal of the transportation component is to compare the results from three models (FESWMS-2DH, DAMBRK, and FLO-2D) that have been suggested as appropriate for evaluating flood flows on alluvial fans with the results obtained from the traditional one-dimensional, stochastic model used in previous research for the Yucca Mountain Project. Progress on all these tasks is described.

  17. Effects of feral horses in Great Basin landscapes on soils and ants: Direct and indirect mechanisms

    USGS Publications Warehouse

    Beever, E.A.; Herrick, J.E.

    2006-01-01

    We compared soil-surface penetration resistance and abundance of ant mounds at 12 western Great Basin sites (composed of 19 plots) either grazed by feral horses (Equus caballus) or having had horses removed for the last 10–14 years. Across this broad spatial domain (3.03 million ha), we minimized confounding due to abiotic factors by selecting horse-occupied and horse-removed sites with similar aspect, slope, fire history, grazing pressure by cattle (minimal to none), and dominant vegetation (Artemisia tridentata). During both 1997 and 1998, we found 2.2–8.4 times greater abundance of ant mounds and 3.0–15.4 times lower penetration resistance in soil surfaces at horse-removed sites. In 1998, thatched Formica ant mounds, which existed predominately at high elevations, were 3.3 times more abundant at horse-removed sites, although abundance varied widely among sites within treatments. Several types of analyses suggested that horses rather than environmental variability were the primary source of treatment differences we observed in ecosystem components. Tests of several predictions suggest that alterations occurred through not only direct effects, but also indirect effects and potentially feedback loops. Free-roaming horses as well as domestic grazers should be considered in conservation planning and land management in the Great Basin, an ecoregion that represents both an outstanding conservation opportunity and challenge.

  18. Great Basin paleoenvironmental studies project; Technical progress report, second quarter, September--November, 1993

    SciTech Connect

    1993-12-31

    Progress is described in the four tasks associated with this project. Task 1, Paleobotanical studies in the Great Basin, has as its objective the reconstruction of the response of vegetation to climate in order to identify periods of mesic climate at Yucca Mountain during the last 20,000 to 50,000 years. Past extremes in infiltration rates are expected to serve as estimates of climate that may be expected during the next 10,000 years at Yucca Mtn. Task 2, Paleofaunas, will construct a history of Great Basin vertebrates that will provide empirical evidence of past environmental and climatic conditions. The objective of Task 3, Geomorphology, is to document the responses of surficial processes and landforms to the climatic changes documented by studies of packrat middens, pollen, and faunal distributions. The goal of Task 4, Transportation, is to compare the results from three models that have been suggested as appropriate for evaluating flood flows on alluvial fans with the results obtained from the traditional one-dimensional, stochastic model used in previous research for Yucca Mountain. This research looked at three alluvial fans with rail transportation alignments crossing them.

  19. Tectonic reconstructions of the southwestern Great Basin: Stratigraphic tests of structural models

    SciTech Connect

    Prave, A.R. . Dept. of Earth and Atmospheric Sciences); Snow, J.K. . Division of Geology and Planetary Sciences)

    1993-04-01

    Accurate paleogeographic reconstruction of the tectonically dismembered southwestern Great Basin is in large part dependent on the validity of the Wernicke et al. (1988) and Snow and Wernicke (1989) correlations of Mesozoic (pre-Tertiary) contractile deformational features. In order to independently assess these structurally based models and their predictions, carefully chosen stratigraphic data were used as tests. In the northern Death Valley region, sediment dispersal trends in two regionally developed facies of the Lower Cambrian Wood Canyon Formation and Zabriskie Quartzite suggest that otherwise uniformly northwest-directed paleocurrent indicators have undergone vertical axis rotations comparable in direction and magnitude to those predicted for anti-clockwise rotation of the Grapevine Mountains structural block. In the central Death Valley region, stratigraphic differences in upper plate rocks in the proposed Tucki Mountain-northern Nopah Range pierce point prevent the adjacent juxtaposition of those rocks but are permissive of such a correlation. Finally, in the southern Death Valley region, the Levy and Christie-Blick (1989) pre-Mesozoic reconstruction results in overlap of range blocks and juxtaposition of disparate facies in the Proterozoic Pahrump Group rocks. This implies that the Cenozoic deformational vector displacement paths, determined for elsewhere in the southern Great Basin, are not applicable to southern Death Valley and must be reassessed.

  20. Conceptual ecological models to guide integrated landscape monitoring of the Great Basin

    USGS Publications Warehouse

    Miller, D.M.; Finn, S.P.; Woodward, Andrea; Torregrosa, Alicia; Miller, M.E.; Bedford, D.R.; Brasher, A.M.

    2010-01-01

    The Great Basin Integrated Landscape Monitoring Pilot Project was developed in response to the need for a monitoring and predictive capability that addresses changes in broad landscapes and waterscapes. Human communities and needs are nested within landscapes formed by interactions among the hydrosphere, geosphere, and biosphere. Understanding the complex processes that shape landscapes and deriving ways to manage them sustainably while meeting human needs require sophisticated modeling and monitoring. This document summarizes current understanding of ecosystem structure and function for many of the ecosystems within the Great Basin using conceptual models. The conceptual ecosystem models identify key ecological components and processes, identify external drivers, develop a hierarchical set of models that address both site and landscape attributes, inform regional monitoring strategy, and identify critical gaps in our knowledge of ecosystem function. The report also illustrates an approach for temporal and spatial scaling from site-specific models to landscape models and for understanding cumulative effects. Eventually, conceptual models can provide a structure for designing monitoring programs, interpreting monitoring and other data, and assessing the accuracy of our understanding of ecosystem functions and processes.

  1. Seismicity and focal mechanisms for the southern Great Basin of Nevada and California: 1987 through 1989

    SciTech Connect

    Harmsen, S.C.; Bufe, C.G.

    1991-12-31

    For the calendar year 1987, the southern Great basin seismic network (SGBSN) recorded about 820 earthquakes in the southern Great Basin (SGB). Local magnitudes ranged from 0.2 to 4.2 (December 30, 1987, 22:50:42 UTC at Hot Creek Valley). Five earthquakes epicenters in 1987 within the detection threshold of the seismic network are at Yucca Mountain, the site of a potential national, high-level nuclear waste repository. The maximum magnitude of those five earthquakes is 1.1, and their estimated depths of focus ranged from 3.1 to 7.6 km below sea level. For the calendar year 1988, about 1280 SGB earthquakes were catalogued, with maximum magnitude-4.4 for an Owens Valley, California, earthquake on July 5, 1988. Eight earthquake epicenters in 1988 are at Yucca Mountain, with depths ranging from three to 12 km below sea level, and maximum magnitude 2.1. For the calendar year 1989, about 1190 SGB earthquakes were located and catalogued, with maximum magnitude equal to 3.5 for earthquake about ten miles north of Las Vegas, Nevada, on January 9. No Yucca Mountain earthquakes were recorded in 1989. An earthquake having a well-constrained depth of about 30 km below sea level was observed on August 21, 1989, in eastern Nevada Test Site (NTS).

  2. Mono Lake Excursion as a Chronologic Marker in the U.S. Great Basin

    NASA Astrophysics Data System (ADS)

    Liddicoat, J. C.; Coe, R. S.; Knott, J. R.

    2008-05-01

    Nevada, Utah, and California east of the Sierra Nevada are in the Great Basin physiographic province of western North America. During periods of the Pleistocene, Lake Bonneville and Lake Lahontan covered valleys in Utah and Nevada, respectively, and other lakes such as Lake Russell in east-central California did likewise (Feth, 1964). Now dry except for its remnant, Mono Lake, Lake Russell provides an opportunity to study behavior of Earth's past magnetic field in lacustrine sediments that are exposed in natural outcrops. The sediments record at least 30,000 years of paleomagnetic secular variation (Liddicoat, 1976; Zimmerman et al., 2006) and have been of particular interest since the discovery of the Mono Lake Excursion (MLE) by Denham and Cox (1971) because the field behavior can be documented at numerous sites around Mono Lake (Liddicoat and Coe, 1979, Liddicoat, 1992; Coe and Liddicoat, 1994) and on Paoha Island in the lake. Moreover, there have been recent attempts to date the excursion (Kent et al., 2002, Benson et al., 2003) more accurately and use the age and relative field intensity in paleoclimate research (Zimmerman et al., 2006). It has been proposed that the excursion in the Mono Basin might be older than originally believed (Denham and Cox, 1971; Liddicoat and Coe, 1979) and instead be the Laschamp Excursion (LE), ~ 40,000 yrs B.P. (Guillou et al., 2004), on the basis of 14C and 40Ar/39Ar dates (Kent et al., 2002) and the relative paleointensity record (Zimmerman et al., 2006) for the excursion in the Mono Basin. On the contrary, we favor a younger age for the excursion, ~ 32,000 yrs B.P., using the relative paleointensity at the Mono and Lahontan basins and 14C dates from the Lahontan Basin (Benson et al., 2003). The age of ~ 32,000 yrs B.P. is in accord with the age (32,000-34,000 yrs B.P.) reported by Channell (2006) for the MLE at Ocean Drilling Program (ODP) Site 919 in the Irminger Basin in the North Atlantic Ocean, which contains as well an

  3. Nivation landforms in the western Great Basin and their paleoclimatic significance

    USGS Publications Warehouse

    Dohrenwend, J.C.

    1984-01-01

    More than 10,000 nivation landforms occur in the higher mountain ranges of the western Great Basin. They range from small, subtle hollows with head scarps a few meters high and a few tens of meters long to broad, clearly defined terraces as much as 220 m wide bounded by bold, steeply sloping head scarps as much as 30 m high and 1600 m long. Distribution of these nivation hollows is strongly influenced by elevation, slope orientation, local relief, and substrate lithology. About 95% occur between 2200 and 3000 m elevation, and nearly 80% are situated on north-northwest-to east-northeast-facing slopes. They occur mainly in areas of moderately sloping terrain and moderate local relief, and they are preferentially developed on relatively incompetent substrates including terrigenous sedimentary deposits, volcanic and metavolcanic rocks of intermediate composition, and deeply weathered granitoid rocks. Nearly all of these nivation hollows are relict. They are most abundant near areas of late Pleistocene glaciation but rarely occur within such areas. Most are veneered with colluvium and are well vegetated, and many hollows in the Mono Basin area are veneered with volcanic ash at least 700 yr old. Distribution of nivation hollows suggests that (1) the full-glacial nivation threshold altitude (NTA) rose from north to south at 190 m per degree of latitude, subparallel to, and approximately 740 m lower than, the full-glacial equilibrium-line altitude (ELA) and about 1370 m lower than the estimated modern ELA; (2) the difference between the full-glacial and modern ELAs indicates an approximate 7??C full-glacial mean-annual-temperature depression throughout the Great Basin; and (3) the full-glacial mean annual temperature at the NTA is estimated to have been approximately 0?? to 1??C, assuming little change in accumulation-season precipitation. ?? 1984.

  4. Heat flow in Railroad Valley, Nevada and implications for geothermal resources in the south-central Great Basin

    USGS Publications Warehouse

    Williams, C.F.; Sass, J.H.

    2006-01-01

    The Great Basin is a province of high average heat flow (approximately 90 mW m-2), with higher values characteristic of some areas and relatively low heat flow (<60 mW m-2) characteristic of an area in south-central Nevada known as the Eureka Low. There is hydrologie and thermal evidence that the Eureka Low results from a relatively shallow, hydrologically controlled heat sink associated with interbasin water flow in the Paleozoic carbonate aquifers. Evaluating this hypothesis and investigating the thermal state of the Eureka Low at depth is a high priority for the US Geological Survey as it prepares a new national geothermal resource assessment. Part of this investigation is focused on Railroad Valley, the site of the largest petroleum reservoirs in Nevada and one of the few locations within the Eureka Low with a known geothermal system. Temperature and thermal conductivity data have been acquired from wells in Railroad Valley in order to determine heat flow in the basin. The results reveal a complex interaction of cooling due to shallow ground-water flow, relatively low (49 to 76 mW m-2) conductive heat flow at depth in most of the basin, and high (up to 234 mW m-2) heat flow associated with the 125??C geothermal system that encompasses the Bacon Flat and Grant Canyon oil fields. The presence of the Railroad Valley geothermal resource within the Eureka Low may be reflect the absence of deep ground-water flow sweeping heat out of the basin. If true, this suggests that other areas in the carbonate aquifer province may contain deep geothermal resources that are masked by ground-water flow.

  5. Fire and Climate History of Mixed Conifer Woodlands in the Great Basin, USA

    NASA Astrophysics Data System (ADS)

    Biondi, F.; Bradley, M.; Cheek, J.; Jamieson, L.; Kilpatrick, M.; Sibold, J.; Strachan, S. D.

    2010-12-01

    We investigated climate, fire, and species dynamics before and after Euro-American settlement at two locations in Lincoln County, Nevada. Both the Mt. Irish and Clover Mountains sites are isolated high ranges in the southern Great Basin Desert, not far from the floristic boundary with the northern Mojave Desert. At Mt. Irish, non-scarred ponderosa pines and single-leaf piñons were used to develop a tree-ring reconstruction of drought (mean PDSI for May-July, NV Clim. Div. 3) from 1396 to 2003. Fire-scarred ponderosas found at both study areas were then sampled, and crossdated fire-scar records were used to generate the fire history. A total of 12 plots, each 0.1 ha in size, was sampled at each site to quantify stand structure, age of surviving trees, and fuel loads. Additional information on species dynamics were collected at regularly spaced grid points. Density of pinyon pine at both sites has more than doubled since Euro-American settlement, with peak survivorship occurring in 1900-1940 at Mount Irish and 1930-1970 at the Clover Mountains. Pre-settlement trees occur throughout each site, particularly at Mount Irish, where in 1550-1860 fires that scarred at least two trees were very frequent (mean fire return interval: 4 years), while fires that scarred at least 10% of the recorder trees were relatively rare (mean fire return interval: 66 years). At the Clover Mountains, for the period 1785-2007, fires that scarred at least two trees and fires that scarred at least 10% of the recorder trees had more similar mean fire return intervals: 7 and 12 years. Fire frequency did not decrease during the 1780-1840 period, when fire was reduced or absent in other areas of the western United States. Much lower fire frequency was noted after Euro-American settlement at Mt. Irish, most likely because of less favorable climatic conditions, while the difference was less pronounced, and also affected by fire suppression activity, at the Clover Mountains. Fuel loads at the two

  6. Major Crustal Fault Zone Trends and Their Relation to Mineral Belts in the North-Central Great Basin, Nevada

    USGS Publications Warehouse

    Rodriguez, Brian D.; Sampson, Jay A.; Williams, Jackie M.

    2007-01-01

    The Great Basin physiographic province covers a large part of the western United States and contains one of the world's leading gold-producing areas, the Carlin Trend. In the Great Basin, many sedimentary-rock-hosted disseminated gold deposits occur along such linear mineral-occurrence trends. The distribution and genesis of these deposits is not fully understood, but most models indicate that regional tectonic structures play an important role in their spatial distribution. Over 100 magnetotelluric (MT) soundings were acquired between 1994 and 2001 by the U.S. Geological Survey to investigate crustal structures that may underlie the linear trends in north-central Nevada. MT sounding data were used to map changes in electrical resistivity as a function of depth that are related to subsurface lithologic and structural variations. Two-dimensional (2-D) resistivity modeling of the MT data reveals primarily northerly and northeasterly trending narrow 2-D conductors (1 to 30 ohm-m) extending to mid-crustal depths (5-20 km) that are interpreted to be major crustal fault zones. There are also a few westerly and northwesterly trending 2-D conductors. However, the great majority of the inferred crustal fault zones mapped using MT are perpendicular or oblique to the generally accepted trends. The correlation of strike of three crustal fault zones with the strike of the Carlin and Getchell trends and the Alligator Ridge district suggests they may have been the root fluid flow pathways that fed faults and fracture networks at shallower levels where gold precipitated in favorable host rocks. The abundant northeasterly crustal structures that do not correlate with the major trends may be structures that are open to fluid flow at the present time.

  7. Late Cenozoic lacustrine and climatic environments at Tule Lake, northern Great Basin, USA

    NASA Astrophysics Data System (ADS)

    Platt Bradbury, J.

    1992-01-01

    Cores of lake sediment to a depth of 334 m in the town of Tulelake, Siskiyou County, northern California, document the late Cenozoic paleolimnologic and paleoclimatic history of the northwestern edge of the Great Basin. The cores have been dated by radiometric, tephrochronologic and paleomagnetic analyses. Lacustrine diatoms are abundant throughout the record and document a nearly continuous paleolimnologic history of the Tule Lake basin for the last 3 Myr. During most of this time, this basin (Tule Lake) was a relatively deep, extensive lake. Except for a drier (and cooler?) interval recorded by Fragilaria species about 2.4 Ma, the Pliocene is characterized by a dominance of planktonic Aulacoseira solida implying a warm monomictic lake under a climatic regime of low seasonality. Much of the Pleistocene is dominated by Stephanodiscus and Fragilaria species suggesting a cooler, often drier, and highly variable climate. Benthic diatoms typical of alkaline-enriched saline waters commonly appear after 1.0 Ma, and tephrochronology indicates slow deposition and possible hiatuses between about 0.6 and 0.2 Ma. The chronology of even-numbered oxygen isotope stages approximately matches fluctuations in the abundance of Fragilaria since 800 ka indicating that glacial periods were expressed as drier environments at Tule Lake. Glacial and interglacial environments since 150 ka were distinct from, and more variable than, those occurring earlier. The last full glacial period was very dry, but shortly thereafter Tule Lake became a deep, cool lacustrine system indicating a substantial increase in precipitation. Aulacoseira ambigua characterized the latest glacial and Holocene record of Tule Lake. Its distribution indicates that warmer and wetter climates began about 15 ka in this part of the Great Basin. Diatom concentration fluctuates at 41 000 year intervals between 3.0 and 2.5 Ma and at approximately 100 000 year intervals after 1.0 Ma. In the late Pliocene and early Pleistocene

  8. Estimation of annual Groundwater Evapotranspiration from Phreatophyte Vegetation in the Great Basin using Remotely Sensed Vegetation Indices and Ground Based Flux Tower measurements

    NASA Astrophysics Data System (ADS)

    Beamer, Jordan P.

    Escalating concerns about the future of water resource management in arid regions of the American Southwest have sparked numerous hydrologic studies looking into available water resources for in-basin and inter-basin transfers. Groundwater is the primary water supply source for much of the state of Nevada and the Great Basin, thus accurate estimates of the regional scale groundwater recharge and discharge components are critical for regional groundwater budgets. Groundwater discharge from phreatophyte vegetation by evapotranspiration (ET) is the dominant component of groundwater discharge in many hydrologically closed valleys of the Great Basin, and can be measured directly from eddy-covariance (EC) and Bowen-ratio (BR) flux tower systems. The purpose of this project was to develop a predictive equation based on relationship between annual ET and meteorological data from EC and BR sites in phreatophyte vegetation with remote sensing data. Annual total ET (ET a) measured from forty site/year combinations of flux tower data from Carson Valley, Walker River Basin, Oasis Valley, Snake Valley, Spring Valley, White River Valley, and the lower Colorado River Flow system were correlated with the Enhanced Vegetation Index (EVI) from Landsat Thematic Mapper (TM) satellite. EVI was extracted from source areas at corresponding locations from 15 mid-summer Landsat TM scenes. ETa was transformed into ET* by subtracting annual precipitation and normalizing by annual reference ET (ETo) (ET*=(ETa-precipitation)/(ETo-precipitation)). ET* correlated well with EVI (r2=0.97), and because it takes basin specific climate measurements into account, it is transferable to many shallow groundwater discharge areas in the Great Basin. This relationship was used to provide a first order estimate of the mean annual groundwater ET (ETg) from four phreatophyte groundwater discharge areas in Nevada using only a mid-summer Landsat EVI image, annual ETo and precipitation data. This simple approach

  9. Chapter B: Regional Geologic Setting of Late Cenozoic Lacustrine Diatomite Deposits, Great Basin and Surrounding Region: Overview and Plans for Investigation

    USGS Publications Warehouse

    Wallace, Alan R.

    2003-01-01

    Freshwater diatomite deposits are present in all of the Western United States, including the Great Basin and surrounding regions. These deposits are important domestic sources of diatomite, and a better understanding of their formation and geologic settings may aid diatomite exploration and land-use management. Diatomite deposits in the Great Basin are the products of two stages: (1) formation in Late Cenozoic lacustrine basins and (2) preservation after formation. Processes that favored long-lived diatom activity and diatomite formation range in decreasing scale from global to local. The most important global process was climate, which became increasingly cool and dry from 15 Ma to the present. Regional processes included tectonic setting and volcanism, which varied considerably both spatially and temporally in the Great Basin region. Local processes included basin formation, sedimentation, hydrology, and rates of processes, including diatom growth and accumulation; basin morphology and nutrient and silica sources were important for robust activity of different diatom genera. Only optimum combinations of these processes led to the formation of large diatomite deposits, and less than optimum combinations resulted in lakebeds that contained little to no diatomite. Postdepositional processes can destroy, conceal, or preserve a diatomite deposit. These processes, which most commonly are local in scale, include uplift, with related erosion and changes in hydrology; burial beneath sedimentary deposits or volcanic flows and tuffs; and alteration during diagenesis and hydrothermal activity. Some sedimentary basins that may have contained diatomite deposits have largely been destroyed or significantly modified, whereas others, such as those in western Nevada, have been sufficiently preserved along with their contained diatomite deposits. Future research on freshwater diatomite deposits in the Western United States and Great Basin region should concentrate on the regional

  10. Chemicals of emerging concern in the Great Lakes Basin: an analysis of environmental exposures.

    PubMed

    Klecka, Gary; Persoon, Carolyn; Currie, Rebecca

    2010-01-01

    This review and statistical analysis was conducted to better understand the nature and significance of environmental exposures in the Great Lakes Basin and watershed to a variety of environmental contaminants. These contaminants of interest included current-use pesticides, pharmaceuticals, organic wastewater contaminants, alkylphenol ethoxylates, perfluorinated surfactants, flame retardants, and chlorinated paraffins. The available literature was critically reviewed and used to develop a database containing 19,611 residue values for 326 substances. In many papers, sampling locations were characterized as being downstream from municipal wastewater discharges, receiving waters for industrial facilities, areas susceptible to agricultural or urban contamination, or harbors and ports. To develop an initial assessment of their potential ecological significance, the contamination levels found were compared with currently available regulatory standards, guidelines, or criteria. This review was prepared for the IJC multi-board work group, and served as background material for an expert consultation, held in March, 2009, in which the significance of the contaminants found was discussed. Moreover, the consultation attempted to identify and assess opportunities for strengthening future actions that will protect the Great Lakes. Based on the findings and conclusions of the expert consultation, it is apparent that a wide variety of chemicals of emerging concern have been detected in environmental media (air, water, sediment, biota) from the Great Lakes Basin, although many are present at only trace levels. Although the presence of these contaminants raises concerns in the public and among the scientific community, the findings must be placed in context. Significant scientific interpretation is required to understand the extent to which these chemicals may pose a threat to the ecosystem and to human health. The ability to detect chemicals in environmental media greatly surpasses

  11. Land cover changes associated with recent energy development in the Williston Basin; Northern Great Plains, USA.

    PubMed

    Preston, Todd M; Kim, Kevin

    2016-10-01

    The Williston Basin in the Northern Great Plains has experienced rapid energy development since 2000. To evaluate the land cover changes resulting from recent (2000-2015) development, the area and previous land cover of all well pads (pads) constructed during this time were determined, the amount of disturbed and reclaimed land adjacent to pads was estimated, land cover changes were analyzed over time for three different well types, and the effects from future development were predicted. The previous land cover of the 12,990ha converted to pads was predominately agricultural (49.5%) or prairie (47.4%) with lesser amounts of developed (2.3%), aquatic (0.5%), and forest (0.4%). Additionally, 12,121ha has likely been disturbed and reclaimed. The area required per gas well remained constant through time while the land required per oil well increased initially and then decreased as development first shifted from conventional to unconventional drilling and then to multi-bore pads. For non-oil-and-gas wells (i.e. stratigraphic test wells, water wells, and injection wells), the area per well increased through time likely due to increased produced water disposal requirements. Future land cover change is expected to be 2.7 times greater than recent development with much of the development occurring in five counties in the core Bakken development area. Direct land cover change and disturbance from recent and expected development are predicted to affect 0.4% of the landscape across the basin; however, in the core Bakken development area, 2.3% of the landscape will be affected including 2.1% of the remaining grassland. Although future development will result in significant land cover change, evolving industry practices and proactive siting decisions, such as development along energy corridors and placing pads in areas previously altered by human activity, have the potential to reduce the ecological effects of future energy development in the Williston Basin. PMID:27318516

  12. First evidence of grass carp recruitment in the Great Lakes Basin

    USGS Publications Warehouse

    Chapman, Duane C.; Davis, J. Jeremiah; Jenkins, Jill A.; Kocovsky, Patrick M.; Miner, Jeffrey G.; Farver, John; Jackson, P. Ryan

    2013-01-01

    We use aging techniques, ploidy analysis, and otolith microchemistry to assess whether four grass carp Ctenopharyngodon idella captured from the Sandusky River, Ohio were the result of natural reproduction within the Lake Erie Basin. All four fish were of age 1 +. Multiple lines of evidence indicate that these fish were not aquaculture-reared and that they were most likely the result of successful reproduction in the Sandusky River. First, at least two of the fish were diploid; diploid grass carp cannot legally be released in the Great Lakes Basin. Second, strontium:calcium (Sr:Ca) ratios were elevated in all four grass carp from the Sandusky River, with elevated Sr:Ca ratios throughout the otolith transect, compared to grass carp from Missouri and Arkansas ponds. This reflects the high Sr:Ca ratio of the Sandusky River, and indicates that these fish lived in a high-strontium environment throughout their entire lives. Third, Sandusky River fish were higher in Sr:Ca ratio variability than fish from ponds, reflecting the high but spatially and temporally variable strontium concentrations of southwestern Lake Erie tributaries, and not the stable environment of pond aquaculture. Fourth, Sr:Ca ratios in the grass carp from the Sandusky River were lower in their 2011 growth increment (a high water year) than the 2012 growth increment (a low water year), reflecting the observed inverse relationship between discharge and strontium concentration in these rivers. We conclude that these four grass carp captured from the Sandusky River are most likely the result of natural reproduction within the Lake Erie Basin.

  13. Land cover changes associated with recent energy development in the Williston Basin; Northern Great Plains, USA

    USGS Publications Warehouse

    Preston, Todd M.; Kim, Kevin

    2016-01-01

    The Williston Basin in the Northern Great Plains has experienced rapid energy development since 2000. To evaluate the land cover changes resulting from recent (2000 – 2015) development, the area and previous land cover of all well pads (pads) constructed during this time was determined, the amount of disturbed and reclaimed land adjacent to pads was estimated, land cover changes were analyzed over time for three different well types, and the effects from future development were predicted. The previous land cover of the 12,990 ha converted to pads was predominately agricultural (49.5%) or prairie (47.4%) with lesser amounts of developed (2.3%), aquatic (0.5%), and forest (0.4%). Additionally, 12,121 ha have likely been disturbed and reclaimed. The area required per gas well remained constant through time while the land required per oil well increased initially and then decreased as development first shifted from conventional to unconventional drilling and then to multi-bore pads. For non-oil-and- gas wells (i.e. stratigraphic test wells, water wells, injection wells, etc.), the area per well increased through time likely due to increased produced water disposal requirements. Future land cover change is expected to be 2.7 times greater than recent development with much of the development occurring in five counties in the core Bakken development area. Direct land cover change and disturbance from recent and expected development are predicted to affect 0.4% of the landscape across the basin; however, in the core Bakken development area, 2.3% of the landscape will be affected including 2.1% of the remaining grassland. Although future development will result in significant land cover change, evolving industry practices and proactive siting decisions, such as development along energy corridors and placing pads in areas previously altered by human activity, have the potential to reduce the ecological effects of future energy development in the Williston Basin.

  14. Late Quaternary Alluvial Fans and Beach Ridge Systems in Jakes Valley, Central Great Basin, USA

    NASA Astrophysics Data System (ADS)

    Garcia, A. F.; Stokes, M.; Benitez, L.

    2002-12-01

    Alluvial fan and lake beach ridge landforms provide archives of the geomorphic response to Late Quaternary climate change within the Great Basin region. This study presents the first detailed results of landform mapping and soil characterization from Jakes Valley, a high altitude (1920m) and internally drained basin, located within a previously unstudied part of White Pine County, East-Central Nevada. Mountain front alluvial fans sourced from the White Pine and Egan Ranges (west-east basin margins) are characterized by four morphostratigraphic units: Qf0 (oldest) through to Qf3 (youngest). Analysis of the soil properties of these stratigraphic units reveals two landform-soil assemblages: 1) Qf0-1, characterized by well-developed calcic soils (stages III+ to IV) and 2) Qf2-3, characterized by less well-developed calcic soils (stages I to II). Beach ridge systems formed during pluvial lake highstands are extensively developed into the mid and distal parts of alluvial fans. Integrated field and aerial photograph mapping has revealed a sequence of between 4-6 ridges with linear and / or highly curved / arcuate morphologies. Beach ridge soil properties are characterized by less well-developed calcic soils (stages I+ to II) that are similar to soils formed in Qf2 alluvial fan units. The interaction between the alluvial fan and beach ridge landforms can be utilized to explore the geomorphic response in relation to climatic amelioration during the Late Pleistocene-Holocene transition. Of particular interest is the common occurrence of the curved / arcuate beach ridges which may correspond to a period of fan progradation coincident with base-level lowering.

  15. Coherence between Great Basin precipitation and low frequency Pacific Ocean variability in CMIP5

    NASA Astrophysics Data System (ADS)

    Smith, K.; Strong, C.; Wang, S.

    2013-12-01

    Precipitation over the northern Wasatch Range of the Great Basin provides water for millions of people, and observations indicate its sensitivity to Pacific sea surface temperature (SST) modes including a 3-7 year El Nino-like pattern and a multidecadal pattern in the north Pacific resembling the Pacific Decadal Oscillation (PDO). We assessed the fidelity of this precipitation-SST connectivity for models participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5) by using historical (1900-2005) monthly model output. Coherence analyses at various lags indicated that the observed precipitation-SST connectivity was best captured by the NCAR Community Climate System Model (CCSM). We show how these results are being used to incorporate low-frequency variations in a nonstationary daily stochastic weather generator suitable for hydrology and ecosystem impact studies out to the year 2100.

  16. Anoxia pre-dates Frasnian-Famennian boundary mass extinction horizon in the Great Basin, USA

    USGS Publications Warehouse

    Bratton, John F.; Berry, William B.N.; Morrow, Jared R.

    1999-01-01

    Major and trace metal results from three Great Basin stratigraphic sections with strong conodont biostratigraphy identify a distinct anoxic interval that precedes, but ends approximately 100 kyr before, the Frasnian–Famennian (F–F, mid-Late Devonian) boundary mass extinction horizon. This horizon corresponds to the final and most severe step of a more protracted extinction period. These results are inconsistent with data reported by others from the upper Kellwasser horizon in Europe, which show anoxia persisting up to the F–F boundary in most sections. Conditions returned to fully oxygenated prior to the F–F boundary in the study area. These data indicate that the worst part of the F–F extinction was not related directly to oceanic anoxia in this region and potentially globally.

  17. Geomorphic interpretation of Skylab photography collected over the Nevada portion of the Great Basin

    NASA Technical Reports Server (NTRS)

    Frater, J. B.; Melhorn, W. N.

    1975-01-01

    Skylab S190B black and white photography has a useful reconnaissance capability in geomorphic mapping of landform features in the arid and semi-arid Great Basin. Enlargement of original photographic data products to a scale of 1:250,000 scale compatible with published topographic maps permits ready identification and classification of most landform elements. However, interpretation suffers through the lack of stereoscopic coverage and introduces problems relating to scale and loss of detail. When aircraft underflight photography for the same area is used as a data enhancement tool, problems of scale, detail, and interpretation are diminished. The combination of orbital and underflight photographic coverage provides a regional overview in which the interrelationships of both micro- and macro-scale landforms become apparent.

  18. Physical Properties and Distribution of Intrusive Rocks (Plutons) in the Great Basin

    NASA Astrophysics Data System (ADS)

    Ponce, D. A.; Watt, J. T.; Glen, J. M.

    2010-12-01

    The distribution of intrusive rocks throughout the Great Basin is important because many plutons are associated with base and precious metal mineral deposits, and may provide insights on regional magmatism and tectonism. Combined information on their physical properties and geophysical signatures will allow improvements on their inferred horizontal extent and facilitate modeling their subsurface structure. Physical property measurements of over 1700 plutonic rock samples in the Great Basin, excluding those in the Sierra Nevada, show an average grain density of about 2670 and a range of about 2260 to 3200 kg/m3; show an average saturated bulk density of about 2630 and a range of about 2290 to 3050 kg/m3; an average magnetic susceptibility of about 0.007 and range from essentially non-magnetic to 0.126 SI-units (equivalent to just over 3 per cent magnetite). As a comparison, over 6,000 granitic samples in the Sierra Nevada (Sikora et al., 1991) have an average grain density of about 2690 and a range of about 2420 to 2780 kg/m3; an average magnetic susceptibility of about 0.006 and range from essentially non-magnetic to 0.016 SI-units (equivalent to about 0.4 per cent magnetite). Remanent magnetizations were measured for selected plutons, for example the remanent magnetization of the Ibapah pluton in the Deep Creek Range, Utah is relatively low and has a Koenigsberger ratio (the ratio between remanent and induced magnetization) of about 0.1. In Nevada, previous pluton extents (Grauch et al., 1988; Grauch , 1996) have been only slightly modified. For example, the Cretaceous to Jurassic stock at Blue Mountain, north-central Nevada (Wilden, 1964) is now mapped as a diorite dike swarm (Wyld, 2002) and thought to be mid-Miocene and related to the inception of the Yellowstone Hotspot (Ponce et al, 2010). Magnetic and gravity data indicate that a possible pluton (or other magnetic basement rock), the top of which could be at moderate crustal depths, is skewed from the

  19. Flea (Siphonaptera) species richness in the Great Basin Desert and island biogeography theory.

    PubMed

    Bossard, Robert L

    2014-06-01

    Numbers of flea (Siphonaptera) species (flea species richness) on individual mammals should be higher on large mammals, mammals with dense populations, and mammals with large geographic ranges, if mammals are islands for fleas. I tested the first two predictions with regressions of H. J. Egoscue's trapping data on flea species richness collected from individual mammals against mammal size and population density from the literature. Mammal size and population density did not correlate with flea species richness. Mammal geographic range did, in earlier studies. The intermediate-sized (31 g), moderately dense (0.004 individuals/m(2)) Peromyscus truei (Shufeldt) had the highest richness with eight flea species on one individual. Overall, island biogeography theory does not describe the distribution of flea species on mammals in the Great Basin Desert, based on H. J. Egoscue's collections. Alternatively, epidemiological or metapopulation theories may explain flea species richness. PMID:24820569

  20. Progressive Seismic Failure, Seismic Gap, and Great Seismic Risk across the Densely Populated North China Basin

    NASA Astrophysics Data System (ADS)

    Yin, A.; Yu, X.; Shen, Z.

    2014-12-01

    Although the seismically active North China basin has the most complete written records of pre-instrumentation earthquakes in the world, this information has not been fully utilized for assessing potential earthquake hazards of this densely populated region that hosts ~200 million people. In this study, we use the historical records to document the earthquake migration pattern and the existence of a 180-km seismic gap along the 600-km long right-slip Tangshan-Hejian-Cixian (THC) fault zone that cuts across the North China basin. The newly recognized seismic gap, which is centered at Tianjin with a population of 11 million people and ~120 km from Beijing (22 million people) and Tangshan (7 million people), has not been ruptured in the past 1000 years by M≥6 earthquakes. The seismic migration pattern in the past millennium suggests that the epicenters of major earthquakes have shifted towards this seismic gap along the THC fault, which implies that the 180- km gap could be the site of the next great earthquake with M≈7.6 if it is ruptured by a single event. Alternatively, the seismic gap may be explained by aseismic creeping or seismic strain transfer between active faults.

  1. Evidence for the sensitivity of a Great Basin terminal lake to storm track position

    NASA Astrophysics Data System (ADS)

    Hatchett, B.; Boyle, D. P.; Garner, C.; Kaplan, M. L.; Bassett, S.

    2014-12-01

    Arid, closed basin watersheds can serve as indicators of regional climate change. In this work we test the hypothesis that surface elevations of Walker Lake, a Great Basin terminal lake, are sensitive to storm track positions. To do so, we use historical climate records, numerically dated paleolakeshore elevations, global reanalysis products and a semi-distributed water balance model. Precipitation and temperature values from calculated wet and dry periods between 1920-2011 were used as input to the model. Storm track climatologies were developed using reanalysis products. Our results demonstrate that a strong relationship exists between historic wet and dry periods and storm track positions. Under the assumption of a stationary climate using these historic wet and dry climates with the model, we simulated lake levels that are consistent with recorded high and lowstands occurring during Heinrich Stadial 1, the Younger Dryas, the Medieval Climate Anomaly and the Little Ice Age. These findings provide direct support for the storm track migration hypothesis. The nonlinear relationship between changes in precipitation and runoff appears to play a critical role in determining why terminal lakes are particularly responsive to changes in storm track positions.

  2. Large-Scale Weather Disturbances in Mars' Southern Extratropics: Sway of the Great Impact Basins

    NASA Astrophysics Data System (ADS)

    Hollingsworth, Jeffery L.; Kahre, Melinda A.

    2014-11-01

    The character of large-scale extratropical synoptic disturbances in Mars' southern hemisphere during late winter through early spring is investigated using a high-resolution version of the NASA Ames Mars global climate model (Mars GCM). This global circulation model imposes interactively lifted (and radiatively active) dust based on a threshold value of the instantaneous surface stress. Compared to observations, the model exhibits a reasonable "dust cycle" (i.e., globally averaged, a more dusty atmosphere during southern spring and summer occurs). In contrast to their northern-hemisphere counterparts, southern synoptic-period weather disturbances and accompanying frontal waves have smaller meridional and zonal scales, and are far less intense synoptically. Influences of the zonally asymmetric (i.e., east-west varying) topography on southern large-scale weather disturbances are examined. Simulations that adapt Mars' full topography compared to simulations that utilize synthetic topographies emulating essential large-scale features of the southern middle latitudes indicate that Mars' transient barotropic/baroclinic eddies are significantly influenced by the great impact basins of this hemisphere (e.g., Argyre and Hellas). In addition, the occurrence of a southern storm zone in late winter and early spring is keyed particularly to the western hemisphere via orographic influences arising from the Tharsis highlands, and the Argyre and Hellas impact basins. Geographically localized transient-wave activity diagnostics are constructed that illuminate fundamental differences amongst such simulations and these are described.

  3. Nitrate in ground water in the Great Valley carbonate subunit of the Potomac River Basin

    USGS Publications Warehouse

    Ferrari, Matthew J.; Ator, Scott W.

    1995-01-01

    Agriculture is the major land use in the carbonate part of the Great Valley of the Potomac River Basin. Applied fertilizer and manure are potential sources of nitrate that can contaminate Groundwater. Nitrate concentrations in Groundwater increased with increasing percentage of cropland but did not decrease with increasing well depth, as has been found in previous studies elsewhere. Samples from 28 wells contained nitrate concentrations ranging from 0.29 to 29 mg/L (milligrams per liter) as nitrogen, with a median concentration of 4.55 mg/L, compared to a median of 1.8 mg/L for 1,056 Groundwater samples from the entire Potomac River Basin. Median nitrate concentrations in Groundwater samples were higher in the Maryland, Pennsylvania, and West Virginia part of the valley, and were lower in the Virginia part (7.45 and 2.95 mg/L, respectively), probably as a result of differences in agricultural land-use patterns; this geographical difference was also noted in surface-water samples (6.65 and 2.3 mg/L, respectively). The area of contribution to each well could not be delineated by surface topography or distance to the well, because Groundwater flow and nitrate transport can be unpredictable in the carbonate region because of fractures and solution channels present.

  4. INTERMEDIARY SUPPORT FOR ECOLOGICAL PROTECTION AND RESTORATION PROJECTS IN THE GREAT LAKES BASIN

    EPA Science Inventory

    The National Fish and Wildlife Foundation will make sub-awards to states, tribes, local governments, non-profit oganizations, and academic institutions working in the Great Lakes watershed. Sub-awards will support activities that implement demonstration practices and tools for p...

  5. The distribution and abundance of archaeal tetraether lipids in U.S. Great Basin hot springs.

    PubMed

    Paraiso, Julienne J; Williams, Amanda J; Huang, Qiuyuan; Wei, Yuli; Dijkstra, Paul; Hungate, Bruce A; Dong, Hailiang; Hedlund, Brian P; Zhang, Chuanlun L

    2013-01-01

    Isoprenoidal glycerol dialkyl glycerol tetraethers (iGDGTs) are core membrane lipids of many archaea that enhance the integrity of cytoplasmic membranes in extreme environments. We examined the iGDGT profiles and corresponding aqueous geochemistry in 40 hot spring sediment and microbial mat samples from the U.S. Great Basin with temperatures ranging from 31 to 95°C and pH ranging from 6.8 to 10.7. The absolute abundance of iGDGTs correlated negatively with pH and positively with temperature. High lipid concentrations, distinct lipid profiles, and a strong relationship between polar and core lipids in hot spring samples suggested in situ production of most iGDGTs rather than contamination from local soils. Two-way cluster analysis and non-metric multidimensional scaling (NMS) of polar iGDGTs indicated that the relative abundance of individual lipids was most strongly related to temperature (r (2) = 0.546), with moderate correlations with pH (r (2) = 0.359), nitrite (r (2) = 0.286), oxygen (r (2) = 0.259), and nitrate (r (2) = 0.215). Relative abundance profiles of individual polar iGDGTs indicated potential temperature optima for iGDGT-0 (≤70°C), iGDGT-3 (≥55°C), and iGDGT-4 (≥60°C). These relationships likely reflect both physiological adaptations and community-level population shifts in response to temperature differences, such as a shift from cooler samples with more abundant methanogens to higher-temperature samples with more abundant Crenarchaeota. Crenarchaeol was widely distributed across the temperature gradient, which is consistent with other reports of abundant crenarchaeol in Great Basin hot springs and suggests a wide distribution for thermophilic ammonia-oxidizing archaea (AOA). PMID:24009605

  6. Mapping and monitoring cheatgrass dieoff in rangelands of the Northern Great Basin, USA

    USGS Publications Warehouse

    Boyte, Stephen P.; Wylie, Bruce K.; Major, Donald J.

    2015-01-01

    Understanding cheatgrass (Bromus tectorum) dynamics in the Northern Great Basin rangelands, USA, is necessary to effectively manage the region’s lands. This study’s goal was to map and monitor cheatgrass performance to identify where and when cheatgrass dieoff occurred in the Northern Great Basin and to discover how this phenomenon was affected by climatic, topographic, and edaphic variables. We also examined how fire affected cheatgrass performance. Land managers and scientists are concerned by cheatgrass dieoff because it can increase land degradation, and its causes and effects are not fully known. To better understand the scope of cheatgrass dieoff, we developed multiple ecological models that integrated remote sensing data with geophysical and biophysical data. The models’ R2 ranged from 0.71 to 0.88, and their root mean squared errors (RMSEs) ranged from 3.07 to 6.95. Validation of dieoff data showed that 41% of pixels within independently developed dieoff polygons were accurately classified as dieoff, whereas 2% of pixels outside of dieoff polygons were classified as dieoff. Site potential, a long-term spatial average of cheatgrass cover, dominated the development of the cheatgrass performance model. Fire negatively affected cheatgrass performance 1 year postfire, but by the second year postfire performance exceeded prefire levels. The landscape-scale monitoring study presented in this paper helps increase knowledge about recent rangeland dynamics, including where cheatgrass dieoffs occurred and how cheatgrass responded to fire. This knowledge can help direct further investigation and/or guide land management activities that can capitalize on, or mitigate the effects of, cheatgrass dieoff.

  7. Detectability of groundwater storage change within the Great Lakes Water Basin using GRACE

    NASA Astrophysics Data System (ADS)

    Huang, J.; Halpenny, J.; van der Wal, W.; Klatt, C.; James, T. S.; Rivera, A.

    2012-08-01

    Groundwater is a primary hydrological reservoir of the Great Lakes Water Basin (GLB), which is an important region to both Canada and US in terms of culture, society and economy. Due to insufficient observations, there is a knowledge gap about groundwater storage variation and its interaction with the Great Lakes. The objective of this study is to examine the detectability of the groundwater storage change within the GLB using the monthly models from the Gravity Recovery And Climate Experiment (GRACE) satellite mission, auxiliary soil moisture, snow and lake (SMSL) data, and predictions from glacial isostatic adjustment (GIA) models. A two-step filtering method is developed to optimize the extraction of GRACE signal. A two dimensional basin window weight function is also introduced to reduce ringing artifacts caused by the band-limited GRACE models in estimating the water storage change within the GLB. The groundwater storage (GWS) as deviation from a reference mean storage is estimated for the period of 2002 to 2009. The average GWS of the GLB clearly show an annual cycle with an amplitude range from 27 to 91 mm in water thickness equivalent (WTE), and a phase range of about two months. The estimated phases of GWS variations have a half year shift with respect to the phase of SMSL water storage variations which show peaks in March and April. The least squares estimation gives a GWS loss trend of from 2.3 to 9.3 km3/yr within the GLB for the period of study. This wide range of the GRACE GWS results is caused largely by the differences of soil moisture and snow storage from different land surface models (LSMs), and to a lesser extent by the GRACE commission and omission errors, and the GIA model error.

  8. Adaptive transitions and environmental change in the northern Great Basin: A view from Diamond Swamp

    SciTech Connect

    Musil, R.R.

    1992-01-01

    The presence of sedentary prehistoric occupations in association with wetland settings in the Great Basin has been the focus of continued debate. Theoretical discussions concerning the nature of hunter-gatherer adaptations to wetland environments have been based on two models: (1) Stress-based or push models, which argue that hunter-gatherer populations would reduce mobility as a response to less favorable conditions, and (2) abundance-based or pull models, which argue that hunter-gatherers would have been attracted to localized environments of diverse and plentiful resources. Archaeological evidence from Diamond Swamp provides insight into human adaptive transitions in wetland environments. Archaeological data from Diamond Swamp revealed a series of cultural components representing significant portions of the Holocene. The components at the Dunn and McCoy Creek sites consist of collections of artifactual, faunal, and floral materials, in association with semi-subterranean pithouse features dated between 3500 and 900 BP. These occupations correspond to periods of increased moisture and higher water tables. During periods of climatic amelioration semi-sedentary occupations occurred with the expansion of highly productive marsh and juniper grassland vegetation zones. The component at the McCoy Creek Site corresponds to a period of decreasing moisture punctuated by periodic drought, evidenced by the presence of a less substantial wickiup occupation dated at 500 BP. This occupation is indicative of a transition to a more mobile, less intensive occupational episode. The study provides evidence that transitions to sedentary pithouse villages in Diamond Swamp are best accounted for by the abundance-based model. A shift towards a less substantial, more mobile, occupation occurred with a decline in effective moisture. The research reflects adaptations made by local hunter-gatherer populations to long term environmental change within a typical Great Basin wetlands setting.

  9. The distribution and abundance of archaeal tetraether lipids in U.S. Great Basin hot springs

    PubMed Central

    Paraiso, Julienne J.; Williams, Amanda J.; Huang, Qiuyuan; Wei, Yuli; Dijkstra, Paul; Hungate, Bruce A.; Dong, Hailiang; Hedlund, Brian P.; Zhang, Chuanlun L.

    2013-01-01

    Isoprenoidal glycerol dialkyl glycerol tetraethers (iGDGTs) are core membrane lipids of many archaea that enhance the integrity of cytoplasmic membranes in extreme environments. We examined the iGDGT profiles and corresponding aqueous geochemistry in 40 hot spring sediment and microbial mat samples from the U.S. Great Basin with temperatures ranging from 31 to 95°C and pH ranging from 6.8 to 10.7. The absolute abundance of iGDGTs correlated negatively with pH and positively with temperature. High lipid concentrations, distinct lipid profiles, and a strong relationship between polar and core lipids in hot spring samples suggested in situ production of most iGDGTs rather than contamination from local soils. Two-way cluster analysis and non-metric multidimensional scaling (NMS) of polar iGDGTs indicated that the relative abundance of individual lipids was most strongly related to temperature (r2 = 0.546), with moderate correlations with pH (r2 = 0.359), nitrite (r2 = 0.286), oxygen (r2 = 0.259), and nitrate (r2 = 0.215). Relative abundance profiles of individual polar iGDGTs indicated potential temperature optima for iGDGT-0 (≤70°C), iGDGT-3 (≥55°C), and iGDGT-4 (≥60°C). These relationships likely reflect both physiological adaptations and community-level population shifts in response to temperature differences, such as a shift from cooler samples with more abundant methanogens to higher-temperature samples with more abundant Crenarchaeota. Crenarchaeol was widely distributed across the temperature gradient, which is consistent with other reports of abundant crenarchaeol in Great Basin hot springs and suggests a wide distribution for thermophilic ammonia-oxidizing archaea (AOA). PMID:24009605

  10. Climate change impacts on the Lehman-Baker Creek drainage in the Great Basin National Park

    NASA Astrophysics Data System (ADS)

    Volk, J. M.

    2013-12-01

    Global climate models (GCMs) forced by increased CO2 emissions forecast anomalously dry and warm trends over the southwestern U.S. for the 21st century. The effect of warmer conditions may result in decreased surface water resources within the Great Basin physiographic region critical for ecology, irrigation and municipal water supply. Here we use downscaled GCM output from the A2 and B1 greenhouse gas emission scenarios to force a Precipitation-Runoff Modeling System (PRMS) watershed model developed for the Lehman and Baker Creeks Drainage (LBCD) in the Great Basin National Park, NV for a century long time period. The goal is to quantify the effects of rising temperature to the water budget in the LBCD at monthly and annual timescales. Dynamically downscaled GCM projections are attained from the NSF EPSCoR Nevada Infrastructure for Climate Change Science, Education, and Outreach project and statistically downscaled output is retrieved from the "U.S. Bias Corrected and Downscaled WCRP CMIP3 Climate Projections". Historical daily climate and streamflow data have been collected simultaneously for periods extending 20 years or longer. Mann-Kendal trend test results showed a statistically significant (α= 0.05) long-term rising trend from 1895 to 2012 in annual and monthly average temperatures for the study area. A grid-based, PRMS watershed model of the LBCD has been created within ArcGIS 10, and physical parameters have been estimated at a spatial resolution of 100m. Simulation results will be available soon. Snow cover is expected to decrease and peak runoff to occur earlier in the spring, resulting in increased runoff, decreased infiltration/recharge, decreased baseflows, and decreased evapo-transpiration.