Sample records for kauner valley central

  1. The Central Valley Hydrologic Model

    NASA Astrophysics Data System (ADS)

    Faunt, C.; Belitz, K.; Hanson, R. T.

    2009-12-01

    Historically, California’s Central Valley has been one of the most productive agricultural regions in the world. The Central Valley also is rapidly becoming an important area for California’s expanding urban population. In response to this competition for water, a number of water-related issues have gained prominence: conjunctive use, artificial recharge, hydrologic implications of land-use change, subsidence, and effects of climate variability. To provide information to stakeholders addressing these issues, the USGS made a detailed assessment of the Central Valley aquifer system that includes the present status of water resources and how these resources have changed over time. The principal product of this assessment is a tool, referred to as the Central Valley Hydrologic Model (CVHM), that simulates surface-water flows, groundwater flows, and land subsidence in response to stresses from human uses and from climate variability throughout the entire Central Valley. The CVHM utilizes MODFLOW combined with a new tool called “Farm Process” to simulate groundwater and surface-water flow, irrigated agriculture, land subsidence, and other key processes in the Central Valley on a monthly basis. This model was discretized horizontally into 20,000 1-mi2 cells and vertically into 10 layers ranging in thickness from 50 feet at the land surface to 750 feet at depth. A texture model constructed by using data from more than 8,500 drillers’ logs was used to estimate hydraulic properties. Unmetered pumpage and surface-water deliveries for 21 water-balance regions were simulated with the Farm Process. Model results indicate that human activities, predominately surface-water deliveries and groundwater pumping for irrigated agriculture, have dramatically influenced the hydrology of the Central Valley. These human activities have increased flow though the aquifer system by about a factor of six compared to pre-development conditions. The simulated hydrology reflects spatial

  2. California's Central Valley Groundwater Study: A Powerful New Tool to Assess Water Resources in California's Central Valley

    USGS Publications Warehouse

    Faunt, Claudia C.; Hanson, Randall T.; Belitz, Kenneth; Rogers, Laurel

    2009-01-01

    Competition for water resources is growing throughout California, particularly in the Central Valley. Since 1980, the Central Valley's population has nearly doubled to 3.8 million people. It is expected to increase to 6 million by 2020. Statewide population growth, anticipated reductions in Colorado River water deliveries, drought, and the ecological crisis in the Sacramento-San Joaquin Delta have created an intense demand for water. Tools and information can be used to help manage the Central Valley aquifer system, an important State and national resource.

  3. Groundwater availability of the Central Valley Aquifer, California

    USGS Publications Warehouse

    Faunt, Claudia C.

    2009-01-01

    California's Central Valley covers about 20,000 square miles and is one of the most productive agricultural regions in the world. More than 250 different crops are grown in the Central Valley with an estimated value of $17 billion per year. This irrigated agriculture relies heavily on surface-water diversions and groundwater pumpage. Approximately one-sixth of the Nation's irrigated land is in the Central Valley, and about one-fifth of the Nation's groundwater demand is supplied from its aquifers. The Central Valley also is rapidly becoming an important area for California's expanding urban population. Since 1980, the population of the Central Valley has nearly doubled from 2 million to 3.8 million people. The Census Bureau projects that the Central Valley's population will increase to 6 million people by 2020. This surge in population has increased the competition for water resources within the Central Valley and statewide, which likely will be exacerbated by anticipated reductions in deliveries of Colorado River water to southern California. In response to this competition for water, a number of water-related issues have gained prominence: conservation of agricultural land, conjunctive use, artificial recharge, hydrologic implications of land-use change, and effects of climate variability. To provide information to stakeholders addressing these issues, the USGS Groundwater Resources Program made a detailed assessment of groundwater availability of the Central Valley aquifer system, that includes: (1) the present status of groundwater resources; (2) how these resources have changed over time; and (3) tools to assess system responses to stresses from future human uses and climate variability and change. This effort builds on previous investigations, such as the USGS Central Valley Regional Aquifer System and Analysis (CV-RASA) project and several other groundwater studies in the Valley completed by Federal, State and local agencies at differing scales. The

  4. Gravity survey of Dixie Valley, west-central Nevada

    USGS Publications Warehouse

    Schaefer, Donald H.

    1983-01-01

    Dixie Valley, a northeast-trending structural trough typical of valleys in the Basin and Range Province, is filled with a maximum of about 10,000 feet of alluvial and lacustrine deposits , as estimated from residual-gravity measurements obtained in this study. On the basis of gravity measurements at 300 stations on nine east-west profiles, the gravity residuals reach a maximum of 30 milligals near the south-central part of the valley. Results from a three-dimensional inversion model indicate that the central depression of the valley is offset to the west of the geographic axis. This offset is probably due to major faulting along the west side of the valley adjacent to the Stillwater Range. Comparison of depths to bedrock obtained during this study and depths obtained from a previous seismic-refraction study indicates a reasonably good correlation. A heterogeneous distribution of densities within the valley-fill deposits would account for differing depths determined by the two methods. (USGS)

  5. Water availability and subsidence in California's Central Valley

    USGS Publications Warehouse

    Faunt, Claudia C.; Sneed, Michelle

    2015-01-01

    California’s Central Valley covers about 52,000 square kilometers (km2) and is one of the most productive agricultural regions in the world. More than 250 different crops are grown in the broad alluvial filled structural trough, with an estimated value exceeding $20 billion per year (Faunt 2009) (Figure 1). Central Valley agriculture depends on state and federal water systems that divert surface water, predominantly originating from Sierra Nevada snowmelt, to agricultural fields. Because the valley is semi-arid and the availability of surface water varies substantially from year to year, season to season, and from north to south, agriculture, as it grew, developed a reliance on groundwater for irrigation.

  6. 75 FR 70020 - Central Valley Project Improvement Act, Water Management Plans

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-16

    ... office on Central Valley Project water conservation best management practices that shall ``* * * develop... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act, Water Management Plans AGENCY: Bureau of Reclamation, Interior ACTION: Notice of Availability. SUMMARY: The...

  7. 77 FR 64544 - Central Valley Project Improvement Act, Water Management Plans

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-22

    ... Central Valley Project water conservation best management practices that shall ``develop criteria for... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act, Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: The...

  8. 76 FR 12756 - Central Valley Project Improvement Act, Water Management Plans

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-08

    ... office on Central Valley Project water conservation best management practices that shall ``* * * develop... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act, Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: The...

  9. 76 FR 54251 - Central Valley Project Improvement Act, Water Management Plans

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-31

    ... and administer an office on Central Valley Project water conservation best management practices that... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act, Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: The...

  10. 75 FR 38538 - Central Valley Project Improvement Act, Water Management Plans

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-02

    ... to establish and administer an office on Central Valley Project water conservation best management... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act, Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: The...

  11. Solar Energy within the Central Valley, CA: Current Practices and Potential

    NASA Astrophysics Data System (ADS)

    Hoffacker, M. K.; Hernandez, R. R.; Allen, M. F.

    2015-12-01

    Utility-scale solar energy (USSE, ≥ 1 megawatt [MW]) systems are rapidly being deployed in the Central Valley of California, generating clean electricity and new job opportunities. Utility-scale solar energy systems require substantial quantities of land or space, often prompting an evaluation of environmental impacts and trade-offs when selecting their placement. Utilizing salt-contaminated agricultural land (as the sodium absorption and electrical conductivity values are unsuitably high), unsuitable for food production, and lands within the built environment (developed), can serve as a co-benefit opportunity when reclamation of these lands for USSE development is prioritized. In this study, we quantify the theoretical and generation-based solar energy potential for the Central Valley according to land-cover type, crop type, and for salt-contaminated lands. Further, we utilize the Carnegie Energy and Environmental Compatibility (CEEC) model to identify and prioritize solar energy, integrating environmental resource opportunities and constraints most relevant to the Central Valley. We use the CEEC model to generate a value-based environmental compatibility output for the Central Valley. The Central Valley extends across nearly 60,000 km2 of California with the potential of generating 21,800 - 30,300 TWh y-1 and 41,600 TWh y-1 of solar energy for photovoltaic (PV) and concentrating solar power (CSP), respectively. Pasture, hay, and cultivated crops comprise over half of the Central Valley, much of which is considered prime agriculture or of statewide or local importance for farming (28,200 km2). Together, approximately one-third of this region is salt-contaminated (16%) or developed (11%). This confers a generation-based potential of 5713 - 7891 TWh y-1 and 2770 TWh y-1 for PV and CSP, respectively. As energy, food, and land are inextricably linked, our study shows how land favorable for renewable energy systems can be used more effectively in places where land is

  12. 76 FR 58840 - Central Valley Project Improvement Act; Refuge Water Management Plans

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-22

    ... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act; Refuge Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: To meet the requirements of the Central Valley Project Improvement Act of 1992 (CVPIA) and subsequent...

  13. Increased body mass of ducks wintering in California's Central Valley

    USGS Publications Warehouse

    Fleskes, Joseph P.; Yee, Julie L.; Yarris, Gregory S.; Loughman, Daniel L.

    2016-01-01

    Waterfowl managers lack the information needed to fully evaluate the biological effects of their habitat conservation programs. We studied body condition of dabbling ducks shot by hunters at public hunting areas throughout the Central Valley of California during 2006–2008 compared with condition of ducks from 1979 to 1993. These time periods coincide with habitat increases due to Central Valley Joint Venture conservation programs and changing agricultural practices; we modeled to ascertain whether body condition differed among waterfowl during these periods. Three dataset comparisons indicate that dabbling duck body mass was greater in 2006–2008 than earlier years and the increase was greater in the Sacramento Valley and Suisun Marsh than in the San Joaquin Valley, differed among species (mallard [Anas platyrhynchos], northern pintail [Anas acuta], America wigeon [Anas americana], green-winged teal [Anas crecca], and northern shoveler [Anas clypeata]), and was greater in ducks harvested late in the season. Change in body mass also varied by age–sex cohort and month for all 5 species and by September–January rainfall for all except green-winged teal. The random effect of year nested in period, and sometimes interacting with other factors, improved models in many cases. Results indicate that improved habitat conditions in the Central Valley have resulted in increased winter body mass of dabbling ducks, especially those that feed primarily on seeds, and this increase was greater in regions where area of post-harvest flooding of rice and other crops, and wetland area, has increased. Conservation programs that continue to promote post-harvest flooding and other agricultural practices that benefit wintering waterfowl and continue to restore and conserve wetlands would likely help maintain body condition of wintering dabbling ducks in the Central Valley of California.

  14. Recent landscape change in California's Central Valley

    NASA Astrophysics Data System (ADS)

    Soulard, C. E.; Wilson, T. S.

    2012-12-01

    Long term monitoring of land use and land cover in California's intensively farmed Central Valley reveals several key physical and socioeconomic factors driving landscape change. As part of the USGS Land Cover Trends Project, we analyzed modern land-use/land-cover change for the California Central Valley ecoregion between 2000 and 2010, monitoring annual change between 2005 and 2010, while creating two new change intervals (2000-2005 and 2005-2010) to update the existing 27-year, interval-based analysis. Between 2000 and 2010, agricultural lands fluctuated due to changes in water allocations and emerging drought conditions, or were lost permanently to development (240 square km). Land-use pressure from agriculture and development also led to a decline in grasslands and shrublands across the region (280 square km). Overall, 400 square km of new developed lands were added in the first decade of the 21st century. From 2007 to 2010, development only expanded by 50 square km, coinciding with defaults in the banking system, the onset of historic foreclosure crisis in California and the global economic downturn. Our annual LULC change estimates capture landscape-level change in response to regional policy changes, climate, and fluctuations (e.g., growth or decline) in the national and global economy. The resulting change data provide insights into the drivers of landscape change in the California Central Valley and the combination of two consistent mapping efforts represents the first continuous, 37-year endeavor of its kind.

  15. Underground water in Sanpete and central Sevier valleys, Utah

    USGS Publications Warehouse

    Richardson, George Burr

    1907-01-01

    Sanpete and central Sevier valleys are situated at the border of the Basin Range and Plateau provinces in south-central Utah. They are bounded on the east by the Wasatch and Sevier plateaus and on the west by the Gunnison Plateau and the Valley and Pavant ranges, and are drained by Sevier River, which empties into Sevier Lake in the Great Basin. (See fig. 1, p. 6.)These valleys rank with the richest parts of the State. They were occupied a few years after the Mormon pioneers founded Salt Lake City, in 1847, when settlements, which soon became thriving farming communities, were established where water for irrigation was most available. A variety of crops, especially wheat, are successfully grown, and the valleys are popularly known as the "granary of Utah." Sheep raising is also an important industry, the adjacent highlands being used for summer pastures. The climate is arid, and there is a striking contrast between those areas which in their natural state are covered with sagebrush and grease wood and the fruitful cultivated tracts. (See PI. I, A and B.) Trees are normally absent in the valleys, but they flourish to a limited extent on the adjacent highlands, where there are thin growths of quaking aspen, scrub oak, and stunted conifers. Irrigation is necessary for the production of crops. Canal systems are maintained by San Pitch Creek and Sevier River, and the mountain streams are tapped by ditches near the mouths of the canyons, but this supply is insufficient and attention is being turned to the subterranean store.This report is a preliminary statement of the general conditions of occurrence of underground water in Sanpete and central Sevier valleys. The field work was carried on in cooperation with Sanpete and Sevier counties through the State engineer, Mr. Caleb Tanner, who detailed Mr. C. S. Jarvis to collect the data embodied in the list of springs and wells on pages 51-60.

  16. 78 FR 21414 - Central Valley Project Improvement Act, Water Management Plans

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-10

    ... Valley Project Improvement Act, Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: The following Water Management Plans are available for review... establish and administer an office on Central Valley Project water conservation best management practices...

  17. Genetics of Central Valley O. mykiss populations: drainage and watershed scale analyses

    USGS Publications Warehouse

    Nielsen, Jennifer L.; Pavey, Scott A.; Wiacek, Talia; Williams, Ian S.

    2005-01-01

    Genetic variation at 11 microsatellite loci described population genetic structure for Oncorhynchus mykiss in the Central Valley, California. Spatial and temporal variation was examined as well as relationships between hatchery and putative natural spawning anadromous stocks. Genetic diversity was analyzed at two distinct spatial scales: fine-scale within drainage for five populations on Clear Creek; between and among drainage diversity for 23 populations. Significant regional spatial structure was apparent, both within Clear Creek and among rainbow trout populations throughout the Central Valley. Significant differences in allelic frequencies were found among most river or drainage systems. Less than 1% of the molecular variance could be attributed to differences found between drainages. Hatchery populations were shown to carry similar genetic diversity to geographically proximate wild populations. Central Valley M = 0.626 (below the M < 0.68 threshold) supported recent population reductions within the Central Valley. However, average estimated effective population size was relatively high (Ne = 5066). Significant allelic differences were found in rainbow trout collected above and below impassable dams on the American, Yuba, Stanislaus and Tuolumne rivers. Rainbow trout sampled in Spring Creek were extremely bottlenecked with allelic variation at only two loci and an estimated effective population size of 62, suggesting some local freshwater O. mykiss stocks may be declining rapidly. These data support significant genetic population structure for steelhead and rainbow trout populations within the Central Valley across multiple scales. Careful consideration of this genetic diversity and its distribution across the landscape should be part of future conservation and restoration efforts. 

  18. Ground-water areas and well logs, central Sevier Valley, Utah

    USGS Publications Warehouse

    Young, Richard A.

    1960-01-01

    Between September 1959 and June 1960 the United States Geological Survey and the Utah State Engineer, with financial assistance from Garfield, Millard, Piute, Sanpete, and Sevier Counties and from local water-users’ associations, cooperated in an investigation to determine the structural framework of the central Sevier Valley and to evaluate the valley’s ground-water potential. An important aspect of the study was the drilling of 22 test holes under private contract. These data and other data collected during the course of the larger ground-water investigation of which the test drilling was a part will be evaluated in a report on the geology and ground-water resources of the central Sevier Valley. The present report has been prepared to make available the logs of test holes and to describe in general terms the availability of ground water in the different areas of the valley.

  19. 76 FR 18581 - Correction; Central Valley Project Improvement Act, Standard Criteria for Agricultural and Urban...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-04

    ... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Correction; Central Valley Project Improvement Act, Standard Criteria for Agricultural and Urban Water Management Plans AGENCY: Bureau of Reclamation... notice in the Federal Register at 76 FR 16818 on the Central Valley Project Improvement Act Standard...

  20. ANALYSIS OF LOTIC MACROINVERTEBRATE ASSEMBLAGES IN CALIFORNIA'S CENTRAL VALLEY

    EPA Science Inventory

    Using multivariate and cluster analyses, we examined the relaitonships between chemical and physical characteristics and macroinvertebrate assemblages at sites sampled by R-EMAP in California's Central Valley. By contrasting results where community structure was summarized as met...

  1. Research Spotlight: Groundwater is being depleted rapidly in California's Central Valley

    NASA Astrophysics Data System (ADS)

    Tretkoff, Ernie

    2011-03-01

    Groundwater is being depleted in California's Central Valley at a rapid rate, according to data from the Gravity Recovery and Climate Experiment (GRACE) satellite. Famiglietti et al. analyzed 78 months of GRACE data covering October 2003 to March 2010 to estimate water storage changes in California's Sacramento and San Joaquin river basins. They found that the basins are losing water at a rate of about 30 millimeters per year equivalent water height, or a total of about 30 cubic kilometers over the 78-month period. Furthermore, they found that two thirds of this loss, or a total of 20 cubic kilometers for the study period, came from groundwater depletion in the Central Valley. Quantifying groundwater depletion can be challenging in many areas because of a lack of monitoring infrastructure and reporting requirements; the study shows that satellite-based monitoring can be a useful way to track groundwater volumes. The authors warn that the current rate of groundwater depletion in the Central Valley may be unsustainable and could have “potentially dire consequences for the economic and food security of the United States.” (Geophysical Research Letters, doi:10.1029/2010GL046442, 2011)

  2. Water availability and land subsidence in the Central Valley, California, USA

    NASA Astrophysics Data System (ADS)

    Faunt, Claudia C.; Sneed, Michelle; Traum, Jon; Brandt, Justin T.

    2016-05-01

    The Central Valley in California (USA) covers about 52,000 km2 and is one of the most productive agricultural regions in the world. This agriculture relies heavily on surface-water diversions and groundwater pumpage to meet irrigation water demand. Because the valley is semi-arid and surface-water availability varies substantially, agriculture relies heavily on local groundwater. In the southern two thirds of the valley, the San Joaquin Valley, historic and recent groundwater pumpage has caused significant and extensive drawdowns, aquifer-system compaction and subsidence. During recent drought periods (2007-2009 and 2012-present), groundwater pumping has increased owing to a combination of decreased surface-water availability and land-use changes. Declining groundwater levels, approaching or surpassing historical low levels, have caused accelerated and renewed compaction and subsidence that likely is mostly permanent. The subsidence has caused operational, maintenance, and construction-design problems for water-delivery and flood-control canals in the San Joaquin Valley. Planning for the effects of continued subsidence in the area is important for water agencies. As land use, managed aquifer recharge, and surface-water availability continue to vary, long-term groundwater-level and subsidence monitoring and modelling are critical to understanding the dynamics of historical and continued groundwater use resulting in additional water-level and groundwater storage declines, and associated subsidence. Modeling tools such as the Central Valley Hydrologic Model, can be used in the evaluation of management strategies to mitigate adverse impacts due to subsidence while also optimizing water availability. This knowledge will be critical for successful implementation of recent legislation aimed toward sustainable groundwater use.

  3. Drought, Land-Use Change, and Water Availability in California's Central Valley

    NASA Astrophysics Data System (ADS)

    Faunt, C. C.; Sneed, M.; Traum, J.

    2015-12-01

    The Central Valley is a broad alluvial-filled structural trough that covers about 52,000 square kilometers and is one of the most productive agricultural regions in the world. Because the valley is semi-arid and the availability of surface water varies substantially from year to year, season to season, and from north to south, agriculture developed a reliance on groundwater for irrigation. During recent drought periods (2007-09 and 2012-present), groundwater pumping has increased due to a combination of factors including drought and land-use changes. In response, groundwater levels have declined to levels approaching or below historical low levels. In the San Joaquin Valley, the southern two thirds of the Central Valley, the extensive groundwater pumpage has caused aquifer system compaction, resulting in land subsidence and permanent loss of groundwater storage capacity. The magnitude and rate of subsidence varies based on geologic materials, consolidation history, and historical water levels. Spatially-variable subsidence has changed the land-surface slope, causing operational, maintenance, and construction-design problems for surface-water infrastructure. It is important for water agencies to plan for the effects of continued water-level declines, storage losses, and/or land subsidence. To combat these effects, excess surface water, when available, is artificially recharged. As surface-water availability, land use, and artificial recharge continue to vary, long-term groundwater-level and land-subsidence monitoring and modelling are critical to understanding the dynamics of the aquifer system. Modeling tools, such as the Central Valley Hydrologic Model, can be used in the analysis and evaluation of management strategies to mitigate adverse impacts due to subsidence, while also optimizing water availability. These analyses will be critical for successful implementation of recent legislation aimed toward sustainable groundwater use.

  4. Water availability and land subsidence in the Central Valley, California, USA

    USGS Publications Warehouse

    Faunt, Claudia; Sneed, Michelle; Traum, Jonathan A.; Brandt, Justin

    2016-01-01

    The Central Valley in California (USA) covers about 52,000 km2 and is one of the most productive agricultural regions in the world. This agriculture relies heavily on surface-water diversions and groundwater pumpage to meet irrigation water demand. Because the valley is semi-arid and surface-water availability varies substantially, agriculture relies heavily on local groundwater. In the southern two thirds of the valley, the San Joaquin Valley, historic and recent groundwater pumpage has caused significant and extensive drawdowns, aquifer-system compaction and subsidence. During recent drought periods (2007–2009 and 2012-present), groundwater pumping has increased owing to a combination of decreased surface-water availability and land-use changes. Declining groundwater levels, approaching or surpassing historical low levels, have caused accelerated and renewed compaction and subsidence that likely is mostly permanent. The subsidence has caused operational, maintenance, and construction-design problems for water-delivery and flood-control canals in the San Joaquin Valley. Planning for the effects of continued subsidence in the area is important for water agencies. As land use, managed aquifer recharge, and surface-water availability continue to vary, long-term groundwater-level and subsidence monitoring and modelling are critical to understanding the dynamics of historical and continued groundwater use resulting in additional water-level and groundwater storage declines, and associated subsidence. Modeling tools such as the Central Valley Hydrologic Model, can be used in the evaluation of management strategies to mitigate adverse impacts due to subsidence while also optimizing water availability. This knowledge will be critical for successful implementation of recent legislation aimed toward sustainable groundwater use.

  5. Satellites measure recent rates of groundwater depletion in California's Central Valley

    NASA Astrophysics Data System (ADS)

    Famiglietti, J. S.; Lo, M.; Ho, S. L.; Bethune, J.; Anderson, K. J.; Syed, T. H.; Swenson, S. C.; de Linage, C. R.; Rodell, M.

    2011-02-01

    In highly-productive agricultural areas such as California's Central Valley, where groundwater often supplies the bulk of the water required for irrigation, quantifying rates of groundwater depletion remains a challenge owing to a lack of monitoring infrastructure and the absence of water use reporting requirements. Here we use 78 months (October, 2003-March, 2010) of data from the Gravity Recovery and Climate Experiment satellite mission to estimate water storage changes in California's Sacramento and San Joaquin River Basins. We find that the basins are losing water at a rate of 31.0 ± 2.7 mm yr-1 equivalent water height, equal to a volume of 30.9 km3 for the study period, or nearly the capacity of Lake Mead, the largest reservoir in the United States. We use additional observations and hydrological model information to determine that the majority of these losses are due to groundwater depletion in the Central Valley. Our results show that the Central Valley lost 20.4 ± 3.9 mm yr-1 of groundwater during the 78-month period, or 20.3 km3 in volume. Continued groundwater depletion at this rate may well be unsustainable, with potentially dire consequences for the economic and food security of the United States.

  6. Winter habitat associations of diurnal raptors in Californias Central Valley

    USGS Publications Warehouse

    Pandolrno, E.R.; Herzog, M.P.; Hooper, S.L.; Smith, Z.

    2011-01-01

    The wintering raptors of California's Central Valley are abundant and diverse. Despite this, little information exists on the habitats used by these birds in winter. We recorded diurnal raptors along 19 roadside survey routes throughout the Central Valley for three consecutive winters between 2007 and 2010. We obtained data sufficient to determine significant positive and negative habitat associations for the White-tailed Kite (Elanus leucurus), Bald Eagle {Haliaeetus leucocephalus), Northern Harrier (Circus cyaneus), Red-tailed Hawk (Buteo jamaicensis), Ferruginous Hawk (Buteo regalis), Rough-legged Hawk (Buteo lagopus), American Kestrel (Falco sparverius), and Prairie Falcon (Falco mexicanus). The Prairie Falcon and Ferruginous and Rough-legged hawks showed expected strong positive associations with grasslands. The Bald Eagle and Northern Harrier were positively associated not only with wetlands but also with rice. The strongest positive association for the White-tailed Kite was with wetlands. The Red-tailed Hawk was positively associated with a variety of habitat types but most strongly with wetlands and rice. The American Kestrel, Northern Harrier, and White-tailed Kite were positively associated with alfalfa. Nearly all species were negatively associated with urbanized landscapes, orchards, and other intensive forms of agriculture. The White-tailed Kite, Northern Harrier, Redtailed Hawk, Ferruginous Hawk, and American Kestrel showed significant negative associations with oak savanna. Given the rapid conversion of the Central Valley to urban and intensive agricultural uses over the past few decades, these results have important implications for conservation of these wintering raptors in this region.

  7. Subsidence and Rebound in California's Central Valley: Effects of Pumping, Geology, and Precipitation

    NASA Astrophysics Data System (ADS)

    Farr, T. G.; Fairbanks, A.

    2017-12-01

    Recent rains in California caused a pause, and even a reversal in some areas, of the subsidence that has plagued the Central Valley for decades. The 3 main drivers of surface deformation in the Central Valley are: Subsurface hydro-geology, precipitation and surface water deliveries, and groundwater pumping. While the geology is relatively fixed in time, water inputs and outputs vary greatly both in time and space. And while subsurface geology and water inputs are reasonably well-known, information about groundwater pumping amounts and rates is virtually non-existent in California. We have derived regional maps of surface deformation in the region for the period 2006 - present which allow reconstruction of seasonal and long-term changes. In order to understand the spatial and temporal patterns of subsidence and rebound in the Central Valley, we have been compiling information on the geology and water inputs and have attempted to infer pumping rates using maps of fallowed fields and published pumping information derived from hydrological models. In addition, the spatial and temporal patterns of hydraulic head as measured in wells across the region allow us to infer the spatial and temporal patterns of groundwater pumping and recharge more directly. A better understanding of how different areas (overlying different stratigraphy) of the Central Valley respond to water inputs and outputs will allow a predictive capability, potentially defining sustainable pumping rates related to water inputs. * work performed under contract to NASA and the CA Dept. of Water Resources

  8. 77 FR 18858 - Remanded Biological Opinions on the Coordinated Long-Term Operation of the Central Valley Project...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-28

    ... Long-Term Operation of the Central Valley Project and State Water Project: Notice of Intent To Prepare... Central Valley Project, in a coordinated manner with the State Water Project, that are likely to avoid... Department of Water Resources, California Department of Fish and Game, State and Federal Contractors Water...

  9. Groundwater depletion and sustainability of irrigation in the US High Plains and Central Valley

    USGS Publications Warehouse

    Scanlon, Bridget R.; Faunt, Claudia; Longuevergne, Laurent; Reedy, Robert C.; Alley, William M.; McGuire, Virginia L.; McMahon, Peter B.

    2012-01-01

    Aquifer overexploitation could significantly impact crop production in the United States because 60% of irrigation relies on groundwater. Groundwater depletion in the irrigated High Plains and California Central Valley accounts for ∼50% of groundwater depletion in the United States since 1900. A newly developed High Plains recharge map shows that high recharge in the northern High Plains results in sustainable pumpage, whereas lower recharge in the central and southern High Plains has resulted in focused depletion of 330 km3 of fossil groundwater, mostly recharged during the past 13,000 y. Depletion is highly localized with about a third of depletion occurring in 4% of the High Plains land area. Extrapolation of the current depletion rate suggests that 35% of the southern High Plains will be unable to support irrigation within the next 30 y. Reducing irrigation withdrawals could extend the lifespan of the aquifer but would not result in sustainable management of this fossil groundwater. The Central Valley is a more dynamic, engineered system, with north/south diversions of surface water since the 1950s contributing to ∼7× higher recharge. However, these diversions are regulated because of impacts on endangered species. A newly developed Central Valley Hydrologic Model shows that groundwater depletion since the 1960s, totaling 80 km3, occurs mostly in the south (Tulare Basin) and primarily during droughts. Increasing water storage through artificial recharge of excess surface water in aquifers by up to 3 km3 shows promise for coping with droughts and improving sustainability of groundwater resources in the Central Valley.

  10. Groundwater depletion and sustainability of irrigation in the US High Plains and Central Valley

    USGS Publications Warehouse

    Scanlon, Bridget R.; Faunt, Claudia C.; Longuevergne, Laurent; Reedy, Robert C.; Alley, William M.; McGuire, Virginia L.; McMahon, Peter B.

    2012-01-01

    Aquifer overexploitation could significantly impact crop production in the United States because 60% of irrigation relies on groundwater. Groundwater depletion in the irrigated High Plains and California Central Valley accounts for ~50% of groundwater depletion in the United States since 1900. A newly developed High Plains recharge map shows that high recharge in the northern High Plains results in sustainable pumpage, whereas lower recharge in the central and southern High Plains has resulted in focused depletion of 330 km3 of fossil groundwater, mostly recharged during the past 13,000 y. Depletion is highly localized with about a third of depletion occurring in 4% of the High Plains land area. Extrapolation of the current depletion rate suggests that 35% of the southern High Plains will be unable to support irrigation within the next 30 y. Reducing irrigation withdrawals could extend the lifespan of the aquifer but would not result in sustainable management of this fossil groundwater. The Central Valley is a more dynamic, engineered system, with north/south diversions of surface water since the 1950s contributing to ~7× higher recharge. However, these diversions are regulated because of impacts on endangered species. A newly developed Central Valley Hydrologic Model shows that groundwater depletion since the 1960s, totaling 80 km3, occurs mostly in the south (Tulare Basin) and primarily during droughts. Increasing water storage through artificial recharge of excess surface water in aquifers by up to 3 km3 shows promise for coping with droughts and improving sustainability of groundwater resources in the Central Valley.

  11. Groundwater depletion and sustainability of irrigation in the US High Plains and Central Valley

    PubMed Central

    Scanlon, Bridget R.; Faunt, Claudia C.; Longuevergne, Laurent; Reedy, Robert C.; Alley, William M.; McGuire, Virginia L.; McMahon, Peter B.

    2012-01-01

    Aquifer overexploitation could significantly impact crop production in the United States because 60% of irrigation relies on groundwater. Groundwater depletion in the irrigated High Plains and California Central Valley accounts for ∼50% of groundwater depletion in the United States since 1900. A newly developed High Plains recharge map shows that high recharge in the northern High Plains results in sustainable pumpage, whereas lower recharge in the central and southern High Plains has resulted in focused depletion of 330 km3 of fossil groundwater, mostly recharged during the past 13,000 y. Depletion is highly localized with about a third of depletion occurring in 4% of the High Plains land area. Extrapolation of the current depletion rate suggests that 35% of the southern High Plains will be unable to support irrigation within the next 30 y. Reducing irrigation withdrawals could extend the lifespan of the aquifer but would not result in sustainable management of this fossil groundwater. The Central Valley is a more dynamic, engineered system, with north/south diversions of surface water since the 1950s contributing to ∼7× higher recharge. However, these diversions are regulated because of impacts on endangered species. A newly developed Central Valley Hydrologic Model shows that groundwater depletion since the 1960s, totaling 80 km3, occurs mostly in the south (Tulare Basin) and primarily during droughts. Increasing water storage through artificial recharge of excess surface water in aquifers by up to 3 km3 shows promise for coping with droughts and improving sustainability of groundwater resources in the Central Valley. PMID:22645352

  12. Isotopic Variability in Central Valley Precipitation Events

    NASA Astrophysics Data System (ADS)

    Keene, D.; Sowers, T.; Wagner, A. J.

    2017-12-01

    Wintertime precipitation in the Sacramento Valley is characterized by two regimes: northerly storms generated by the polar jet stream and southerly storms generated by subtropical atmospheric rivers (ARs). Polar jet stream storms account for the majority of storm activity in the central valley, but the amount of subtropical moisture available for transport tends to increase during El Niño years. However, during the El Niño of 2015-2016, California continued to experience drought conditions with the Sacramento area receiving below average wintertime precipitation. Although the 2016-2017 winter was not an El Niño year, the Sacramento area received more than 190% of its average precipitation from ARs in the opening months of 2017. While this suggests that ARs are a significant part of California's hydrologic cycle independent of El Niño, it has not been established whether these storms have an isotopically distinct signature compared to those generated by the polar jet stream or if their signature covaries with ENSO. To investigate the potential isotopic variability of ARs, rainwater was collected over a period of three years in the Sacramento Valley and the surrounding areas and analyzed for δD and δ18O. Since El Niño is generally considered to cause an increase in the amount of available subtropical moisture delivered to the Sacramento valley, we would expect precipitation during those years to be less depleted than precipitation in non-El Niño years. On average, δD and δ18O values of precipitation during the 2015-2016 winter were not significantly different compared to precipitation from 2016-2017 even though 2016-2017 was dominated by historic amounts of AR rainfall. This suggests that the frequency and intensity of atmospheric river storm events may not be intimately linked with the ENSO cycle.

  13. Mapping Aquifer Systems with Airborne Electromagnetics in the Central Valley of California

    NASA Astrophysics Data System (ADS)

    Knight, R. J.; Smith, R.; Asch, T. H.; Abraham, J.; Cannia, J.; Fogg, G. E.; Viezzoli, A.

    2016-12-01

    The Central Valley of California is an important agricultural region struggling to meet the need for irrigation water. Recent periods of drought have significantly reduced the delivery of surface water, resulting in extensive pumping of groundwater. This has exacerbated an already serious problem in the Central Valley, where a number of areas have experienced declining water levels for several decades leading to ongoing concerns about depletion of aquifers and impacts on ecosystems, as well as subsidence of the ground surface. The overdraft has been so significant, that there are now approximately140 million acre-feet (MAF) of unused groundwater storage in the Central Valley, storage that could be used to complement the 42 MAF of surface storage. The alluvial sedimentary geology of the Central Valley is typically composed of more than 50 to 70 percent fine-grained deposits dominated by silt and clay beds. These fine grained deposits can block potential recharge, and are associated with the large amount of observed subsidence. Fortunately, the geologic processes that formed the region created networks of sand and gravel which provide both a supply of water and pathways for recharge from the surface to the aquifers. The challenge is to find these sand and gravel deposits and thus identify optimal locations for surface spreading techniques so that recharge could be dramatically increased, and re-pressurization of the confined aquifer networks could be accomplished. We have acquired 100 line kilometers of airborne electromagnetic data over an area in the San Joaquin Valley, imaging the subsurface hydrostratigraphy to a depth of 500 m with spatial resolution on the order of meters to tens of meters. Following inversion of the data to obtain resistivity models along the flight lines, we used lithology logs in the area to transform the models to images displaying the distribution of sand and gravel, clay, and mixed fine and coarse materials. The quality of the data and

  14. Residence Times in Central Valley Aquifers Recharged by Dammed Rivers

    NASA Astrophysics Data System (ADS)

    Loustale, M.; Paukert Vankeuren, A. N.; Visser, A.

    2017-12-01

    Groundwater is a vital resource for California, providing between 30-60% of the state's water supply. Recent emphasis on groundwater sustainability has induced a push to characterize recharge rates and residence times for high priority aquifers, including most aquifers in California's Central Valley. Flows in almost all rivers from the western Sierra to the Central Valley are controlled by dams, altering natural flow patterns and recharge to local aquifers. In eastern Sacramento, unconfined and confined shallow aquifers (depth <300 feet) are recharged by a losing reach of the Lower American River, despite the presence of levees with slurry cut-off walls.1 Flow in the Lower American River is controlled through the operation of the Folsom and Nimbus Dams, with a minimum flow of 500 cfs. Water table elevation in wells in close proximity to the river are compared to river stage to determine the effect of river stage on groundwater recharge rates. Additionally, Tritium-3Helium dates and stable isotopes (∂18O and ∂2H) have been measured in monitoring wells 200- 2400 ft lateral distance from the river, and depths of 25 -225 feet BGS. Variation in groundwater age in the vertical and horizontal directions are used to determine groundwater flow path and velocity. These data are then used to calculate residence time of groundwater in the unconfined and confined aquifer systems for the Central Valley in eastern Sacramento. Applying groundwater age tracers can benefit future compliance metrics of the California Sustainable Groundwater Resources Act (SGMA), by quantifying river seepage rates and impacts of groundwater management on surface water resources. 1Moran et al., UCRL-TR-203258, 2004.

  15. Hydrogeologic framework of Antelope Valley and Bedell Flat, Washoe County, west-central Nevada

    USGS Publications Warehouse

    Berger, D.L.; Ponce, D.A.; Ross, W.C.

    2001-01-01

    Description of the hydrogeologic framework of Antelope Valley and Bedell Flat in west-central Nevada adds to the general knowledge of regional ground-water flow north of the Reno-Sparks metropolitan area. The hydrogeologic framework is defined by the rocks and deposits that transmit ground water or impede its movement and by the combined thickness of Cenozoic deposits. When data are lacking about the subsurface geology of an area, geophysical methods can be used to provide additional information. In this study, gravimetric and seismic-refraction methods were used to infer the form of structural features and to estimate the thickness of Cenozoic deposits in each of the two valleys. In Antelope Valley, the thickness of these deposits probably does not exceed about 300 feet, suggesting that ground-water storage in the basin-fill aquifer is limited. Beneath Bedell Flat is an elongated, northeast-trending structural depression in the pre-Cenozoic basement; the maximum thickness of Cenozoic deposits is about 2,500 feet beneath the south-central part of the valley. Shallow ground water in the northwest corner of Bedell Flat may be a result of decreasing depth to the pre-Cenozoic basement.

  16. Winter fog is decreasing in the fruit growing region of the Central Valley of California

    NASA Astrophysics Data System (ADS)

    Baldocchi, Dennis; Waller, Eric

    2014-05-01

    The Central Valley of California is home to a variety of fruit and nut trees. These trees account for 95% of the U.S. production, but they need a sufficient amount of winter chill to achieve rest and quiescence for the next season's buds and flowers. In prior work, we reported that the accumulation of winter chill is declining in the Central Valley. We hypothesize that a reduction in winter fog is cooccurring and is contributing to the reduction in winter chill. We examined a 33 year record of satellite remote sensing to develop a fog climatology for the Central Valley. We find that the number of winter fog events, integrated spatially, decreased 46%, on average, over 32 winters, with much year to year variability. Less fog means warmer air and an increase in the energy balance on buds, which amplifies their warming, reducing their chill accumulation more.

  17. 77 FR 33240 - Central Valley Project Improvement Act, Water Management Plans

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-05

    ... Project water conservation best management practices that shall ``develop criteria for evaluating the... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act, Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: The...

  18. Ground-water quality in east-central Idaho valleys

    USGS Publications Warehouse

    Parliman, D.J.

    1982-01-01

    From May through November 1978, water quality, geologic, and hydrologic data were collected for 108 wells in the Lemhi, Pahsimeroi, Salman River (Stanley to Salmon), Big Lost River, and Little Lost River valleys in east-central Idaho. Data were assembled to define, on a reconnaissance level, water-quality conditions in major aquifers and to develop an understanding of factors that affected conditions in 1978 and could affect future ground-water quality. Water-quality characteristics determined include specific conductance, pH, water temperature, major dissolved cations, major dissolved anions, and coliform bacteria. Concentrations of hardness, nitrite plus nitrate, coliform bacteria, dissolved solids, sulfate, chloride, fluoride , iron, calcium, magnesium, sodium, potassium or bicarbonate exceed public drinking water regulation limits or were anomalously high in some water samples. Highly mineralized ground water probably is due to the natural composition of the aquifers and not to surface contamination. Concentrations of coliform bacteria that exceed public drinking water limits and anomalously high dissolved nitrite-plus-nitrite concentrations are from 15- to 20-year old irrigation wells in heavily irrigated or more densely populated areas of the valleys. Ground-water quality and quantity in most of the study area are sufficient to meet current (1978) population and economic demands. Ground water in all valleys is characterized by significant concentrations of calcium, magnesium, and bicarbonate plus carbonate ions. Variations in the general trend of ground-water composition (especially in the Lemhi Valley) probably are most directly related to variability in aquifer lithology and proximity of sampling site to source of recharge. (USGS)

  19. Hydrogeologic framework of the Wood River Valley aquifer system, south-central Idaho

    USGS Publications Warehouse

    Bartolino, James R.; Adkins, Candice B.

    2012-01-01

    metamorphosed to some degree, thus rock types and their relationships vary over distance. Quaternary-age sediment and basalt compose the primary source of groundwater in the Wood River Valley aquifer system. These Quaternary deposits can be divided into three units: a coarse-grained sand and gravel unit, a fine-grained silt and clay unit, and a single basalt unit. The fine- and coarse-grained units were primarily deposited as alluvium derived from glaciation in the surrounding mountains and upper reaches of tributary canyons. The basalt unit is found in the southeastern Bellevue fan area and is composed of two flows of different ages. Most of the groundwater produced from the Wood River Valley aquifer system is from the coarse-grained deposits. The altitude of the pre-Quaternary bedrock surface in the Wood River Valley was compiled from about 1,000 well-driller reports for boreholes drilled to bedrock and about 70 Horizontal-to-Vertical Spectral Ratio (HVSR) ambient-noise measurements. The bedrock surface generally mimics the land surface by decreasing down tributary canyons and the main valley from north to south; it ranges from more than 6,700 feet in Baker Creek to less than 4,600 feet in the central Bellevue fan. Most of the south-central portion of the Bellevue fan is underlain by an apparent topographically closed area on the bedrock surface that appears to drain to the southwest towards Stanton Crossing. Quaternary sediment thickness ranges from less than a foot on main and tributary valley margins to about 350 feet in the central Bellevue fan. Hydraulic conductivity for 81 wells in the study area was estimated from well-performance tests reported on well-driller reports. Estimated hydraulic conductivity for 79 wells completed in alluvium ranges from 1,900 feet per day (ft/d) along Warm Springs Creek to less than 1 ft/d in upper Croy Canyon. A well completed in bedrock had an estimated hydraulic conductivity value of 10 ft/d, one well completed in basalt had a value of

  20. Thirty Years of Cloud Cover Patterns from Satellite Data: Fog in California's Central Valley and Coast

    NASA Astrophysics Data System (ADS)

    Waller, E.; Baldocchi, D. D.

    2012-12-01

    In an effort to assess long term trends in winter fog in the Central Valley of California, custom maps of daily cloud cover from an approximately 30 year record of AVHRR (1981-1999) and MODIS (2000-2012) satellite data were generated. Spatial rules were then used to differentiate between fog and general cloud cover. Differences among the sensors (e.g., spectral content, spatial resolution, overpass time) presented problems of consistency, but concurrent climate station data were used to resolve systematic differences in products, and to confirm long term trends. The frequency and extent of Central Valley ("Tule") fog appear to have some periodic oscillation, but also appear to be on the decline, especially in the Sacramento Valley and in the "shoulder" months of November and February. These results may have strong implications for growers of fruit and nut trees in the Central Valley dependent on winter chill hours that are augmented by the foggy daytime conditions. Conclusions about long term trends in fog are limited to daytime patterns, as results are primarily derived from reflectance-based products. Similar analyses of daytime cloud cover are performed on other areas of concern, such as the coastal fog belt of California. Large area and long term patterns here appear to have periodic oscillation similar to that for the Central Valley. However, the relatively coarse spatial resolution of the AVHRR LTDR (Long Term Data Record) data (~5-km) may be limiting for fine-scale analysis of trends.

  1. Transboundary Contributions To Surface Ozone In California's Central Valley

    NASA Astrophysics Data System (ADS)

    Post, A.; Faloona, I. C.; Conley, S. A.; Lighthall, D.

    2014-12-01

    Rising concern over the impacts of exogenous air pollution in California's Central Valley has prompted the establishment of a coastal, high altitude monitoring site at the Chews Ridge Observatory (1550 m) approximately 30 km east of Point Sur in Monterey County, under the auspices of the Monterey Institute for Research in Astronomy. Two and a half years of continuous ozone data are presented in the context of long-range transport and its potential impact on surface air quality in the San Joaquin Valley (SJV). Past attempts to quantify the impact of transboundary ozone on surface levels have relied on uncertain model estimates, or have been limited to weekly ozonesonde data. Here, we present an observationally derived quantification of the contribution of free tropospheric ozone to surface sites in the San Joaquin Valley throughout three ozone seasons (June through September, 2012-2014). The diurnal ozone patterns at Chews Ridge, and their correlations with ozone aloft over the Valley, have been presented previously. Furthermore, reanalysis data of geopotential heights indicate consistent flow from Chews Ridge to the East, directly over the SJV. In a related airborne project we quantify the vertical exchange, or entrainment, rate over the Southern SJV from a series of focused flights measuring ozone concentrations during peak photochemical hours in conjunction with local meteorological data to quantify an ozone budget for the area. By applying the entrainment rates observed in that study here we are able to quantify the seasonal contributions of free tropospheric ozone measured at Chews Ridge to surface sites in the San Joaquin Valley, and compare prior model estimates to our observationally derived values.

  2. Recent land-use/land-cover change in the Central California Valley

    USGS Publications Warehouse

    Soulard, Christopher E.; Wilson, Tamara S.

    2013-01-01

    Open access to Landsat satellite data has enabled annual analyses of modern land-use and land-cover change (LULCC) for the Central California Valley ecoregion between 2005 and 2010. Our annual LULCC estimates capture landscape-level responses to water policy changes, climate, and economic instability. From 2005 to 2010, agriculture in the region fluctuated along with regulatory-driven changes in water allocation as well as persistent drought conditions. Grasslands and shrublands declined, while developed lands increased in former agricultural and grassland/shrublands. Development rates stagnated in 2007, coinciding with the onset of the historic foreclosure crisis in California and the global economic downturn. We utilized annual LULCC estimates to generate interval-based LULCC estimates (2000–2005 and 2005–2010) and extend existing 27 year interval-based land change monitoring through 2010. Resulting change data provides insights into the drivers of landscape change in the Central California Valley ecoregion and represents the first, continuous, 37 year mapping effort of its kind.

  3. A Comparison of Groundwater Storage Using GRACE Data, Groundwater Levels, and a Hydrological Model in Californias Central Valley

    NASA Technical Reports Server (NTRS)

    Kuss, Amber; Brandt, William; Randall, Joshua; Floyd, Bridget; Bourai, Abdelwahab; Newcomer, Michelle; Skiles, Joseph; Schmidt, Cindy

    2011-01-01

    The Gravity Recovery and Climate Experiment (GRACE) measures changes in total water storage (TWS) remotely, and may provide additional insight to the use of well-based data in California's agriculturally productive Central Valley region. Under current California law, well owners are not required to report groundwater extraction rates, making estimation of total groundwater extraction difficult. As a result, other groundwater change detection techniques may prove useful. From October 2002 to September 2009, GRACE was used to map changes in TWS for the three hydrological regions (the Sacramento River Basin, the San Joaquin River Basin, and the Tulare Lake Basin) encompassing the Central Valley aquifer. Net groundwater storage changes were calculated from the changes in TWS for each of the three hydrological regions and by incorporating estimates for additional components of the hydrological budget including precipitation, evapotranspiration, soil moisture, snow pack, and surface water storage. The calculated changes in groundwater storage were then compared to simulated values from the California Department of Water Resource's Central Valley Groundwater- Surface Water Simulation Model (C2VSIM) and their Water Data Library (WDL) Geographic Information System (GIS) change in storage tool. The results from the three methods were compared. Downscaling GRACE data into the 21 smaller Central Valley sub-regions included in C2VSIM was also evaluated. This work has the potential to improve California's groundwater resource management and use of existing hydrological models for the Central Valley.

  4. 76 FR 16818 - Central Valley Project Improvement Act, Standard Criteria for Ag and Urban Water Management Plans

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-25

    ... Valley Project water conservation best management practices (BMPs) that shall develop Criteria for... project contractors using best available cost- effective technology and best management practices.'' The... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act, Standard...

  5. Potential effects of drought on carrying capacity for wintering waterfowl in the Central Valley of California

    USGS Publications Warehouse

    Petrie, Mark J.; Fleskes, Joseph P.; Wolder, Mike A.; Isola, Craig R.; Yarris, Gregory S.; Skalos, Daniel A.

    2016-01-01

    We used the bioenergetics model TRUEMET to evaluate potential effects of California's recent drought on food supplies for waterfowl wintering in the Central Valley under a range of habitat and waterfowl population scenarios. In nondrought years in the current Central Valley landscape, food supplies are projected to be adequate for waterfowl from fall through early spring (except late March) even if waterfowl populations reach North American Waterfowl Management Plan goals. However, in all drought scenarios that we evaluated, food supplies were projected to be exhausted for ducks by mid- to late winter and by late winter or early spring for geese. For ducks, these results were strongly related to projected declines in winter-flooded rice fields that provide 45% of all the food energy available to ducks in the Central Valley in nondrought water years. Delayed flooding of some managed wetlands may help alleviate food shortages by providing wetland food resources better timed with waterfowl migration and abundance patterns in the Central Valley, as well as reducing the amount of water needed to manage these habitats. However, future research is needed to evaluate the impacts of delayed flooding on waterfowl hunting, and whether California's existing water delivery system would make delayed flooding feasible. Securing adequate water supplies for waterfowl and other wetland-dependent birds is among the greatest challenges facing resource managers in coming years, especially in the increasingly arid western United States.

  6. Projected Impacts of Climate, Urbanization, Water Management, and Wetland Restoration on Waterbird Habitat in California's Central Valley.

    PubMed

    Matchett, Elliott L; Fleskes, Joseph P

    2017-01-01

    The Central Valley of California is one of the most important regions for wintering waterbirds in North America despite extensive anthropogenic landscape modification and decline of historical wetlands there. Like many other mediterranean-climate ecosystems across the globe, the Central Valley has been subject to a burgeoning human population and expansion and intensification of agricultural and urban development that have impacted wildlife habitats. Future effects of urban development, changes in water supply management, and precipitation and air temperature related to global climate change on area of waterbird habitat in the Central Valley are uncertain, yet potentially substantial. Therefore, we modeled area of waterbird habitats for 17 climate, urbanization, water supply management, and wetland restoration scenarios for years 2006-2099 using a water resources and scenario modeling framework. Planned wetland restoration largely compensated for adverse effects of climate, urbanization, and water supply management changes on habitat areas through 2065, but fell short thereafter for all except one scenario. Projected habitat reductions due to climate models were more frequent and greater than under the recent historical climate and their magnitude increased through time. After 2065, area of waterbird habitat in all scenarios that included severe warmer, drier climate was projected to be >15% less than in the "existing" landscape most years. The greatest reduction in waterbird habitat occurred in scenarios that combined warmer, drier climate and plausible water supply management options affecting priority and delivery of water available for waterbird habitats. This scenario modeling addresses the complexity and uncertainties in the Central Valley landscape, use and management of related water supplies, and climate to inform waterbird habitat conservation and other resource management planning. Results indicate that increased wetland restoration and additional

  7. Drought impacts to water footprints and virtual water transfers of the Central Valley of California

    NASA Astrophysics Data System (ADS)

    Marston, Landon; Konar, Megan

    2017-07-01

    The Central Valley of California is one of the most productive agricultural locations in the world, which is made possible by a complex and vast irrigation system. Beginning in 2012, California endured one of the worst droughts in its history. Local impacts of the drought have been evaluated, but it is not yet well understood how the drought reverberated through the global food system. Here we quantify drought impacts to the water footprint (WF) of agricultural production and virtual water transfers (VWT) from the Central Valley of California. To do this, we utilize high-resolution spatial and temporal data sets and a crop model from predrought conditions (2011) through 3 years of exceptional drought (2012-2014). Despite a 12% reduction in harvested area, the WF of agricultural production in the Central Valley increased by 3%. This was due to greater crop water requirements from higher temperatures and a shift to more water-intensive orchard and vine crops. The groundwater WF increased from 7.00 km3 in 2011 to 13.63 km3 in 2014, predominantly in the Tulare Basin. Transfers of food commodities declined by 1% during the drought, yet total VWT increased by 3% (0.51 km3). From 2011 to 2014, groundwater VWT increased by 3.42 km3, offsetting the 0.94 km3 reduction in green VWT and the 1.96 km3 decrease in surface VWT. During the drought, local and global consumers nearly doubled their reliance on the Central Valley Aquifer. These results indicate that drought may strengthen the telecoupling between groundwater withdrawals and distant consumers of agricultural commodities.

  8. Contaminated fish consumption in California's Central Valley Delta.

    PubMed

    Shilling, Fraser; White, Aubrey; Lippert, Lucas; Lubell, Mark

    2010-05-01

    Extensive mercury contamination and angler selection of the most contaminated fish species coincide in California's Central Valley. This has led to a policy conundrum: how to balance the economic and cultural impact of advising subsistence anglers to eat less fish with the economic cost of reducing the mercury concentrations in fish? State agencies with regulatory and other jurisdictional authority lack sufficient data and have no consistent approach to this problem. The present study focused on a critical and contentious region in California's Central Valley (the Sacramento-San Joaquin Rivers Delta) where mercury concentrations in fish and subsistence fishing rates are both high. Anglers and community members were surveyed for their fish preferences, rates of consumption, the ways that they receive health information, and basic demographic information. The rates of fish consumption for certain ethnicities were higher than the rates used by state agencies for planning pollution remediation. A broad range of ethnic groups were involved in catching and eating fish. The majority of anglers reported catching fish in order to feed to their families, including children and women of child-bearing age. There were varied preferences for receiving health information and no correlation between knowledge of fish contamination and rates of consumption. Calculated rates of mercury intake by subsistence anglers were well above the EPA reference dose. The findings here support a comprehensive policy strategy of involvement of the diverse communities in decision-making about education and clean-up and an official recognition of subsistence fishers in the region. Copyright 2010 Elsevier Inc. All rights reserved.

  9. Investigating Groundwater Depletion and Aquifer Degradation in Central Valley California from Space

    NASA Astrophysics Data System (ADS)

    Ojha, C.; Shirzaei, M.; Werth, S.; Argus, D. F.

    2017-12-01

    The Central Valley in California includes one of the world's largest and yet most stressed aquifer systems. The large demand for groundwater, accelerated by population growth and extreme droughts, has been depleting the region's groundwater resources for decades. However, the lack of dense monitoring networks and inaccurate information on geophysical aquifer response pose serious challenges to water management efforts in the area and put the groundwater at high risk. Here, we performed a joint analysis of large SAR interferometric data sets acquired by ALOS L-band satellite in conjunction with the groundwater level observations across the Central Valley. We used 420 L-band SAR images acquired on the ascending orbit track during period Dec 24, 2006 - Jan 1, 2010, and generated more than 1600 interferograms with a pixel size of 100 m × 100 m. We also use data from 1600 observational wells providing continuous measurements of groundwater level within the study period for our analysis. We find that in the south and near Tulare Lake, north of Tule and south of Kaweah basin in San Joaquin valley, the subsidence rate is greatest at up to 20-25 cm/yr, while in Sacramento Valley the subsidence rate is lower at 1-3 cm/yr. From the characterization of the elastic and inelastic storage coefficients, we find that Kern, Tule, Tulare, Kaweah and Merced basins in the San Joaquin Valley are more susceptible to permanent compaction and aquifer storage loss. Kern County shows 0.23%-1.8% of aquifer storage loss during the study period, and has higher percentage loss than adjacent basins such as Tule and Tulare Lake with 0.15%-1.2% and 0.2 %-1.5% loss, respectively. Overall, we estimate that the aquifers across the valley lost a total of 28 km3 of groundwater and 2% of their storage capacity during the study period. Our unique observational evidence including valley-wide estimate of mechanical properties of aquifers and model results will not only facilitate monitoring water deficits

  10. Mapping Aquifer Systems with Airborne Electromagnetics in the Central Valley of California.

    PubMed

    Knight, Rosemary; Smith, Ryan; Asch, Ted; Abraham, Jared; Cannia, Jim; Viezzoli, Andrea; Fogg, Graham

    2018-03-09

    The passage of the Sustainable Groundwater Management Act in California has highlighted a need for cost-effective ways to acquire the data used in building conceptual models of the aquifer systems in the Central Valley of California. One approach would be the regional implementation of the airborne electromagnetic (AEM) method. We acquired 104 line-kilometers of data in the Tulare Irrigation District, in the Central Valley, to determine the depth of investigation (DOI) of the AEM method, given the abundance of electrically conductive clays, and to assess the usefulness of the method for mapping the hydrostratigraphy. The data were high quality providing, through inversion of the data, models displaying the variation in electrical resistivity to a depth of approximately 500 m. In order to transform the resistivity models to interpreted sections displaying lithology, we established the relationship between resistivity and lithology using collocated lithology logs (from drillers' logs) and AEM data. We modeled the AEM response and employed a bootstrapping approach to solve for the range of values in the resistivity model corresponding to sand and gravel, mixed coarse and fine, and clay in the unsaturated and saturated regions. The comparison between the resulting interpretation and an existing cross section demonstrates that AEM can be an effective method for mapping the large-scale hydrostratigraphy of aquifer systems in the Central Valley. The methods employed and developed in this study have widespread application in the use of the AEM method for groundwater management in similar geologic settings. © 2018 The Authors. Groundwater published by Wiley Periodicals, Inc. on behalf of National Ground Water Association.

  11. The Effects of Mountaintop Mines and Valley Fills on Aquatic Ecosystems of the Central Appalachian Coalfields (2011 Final)

    EPA Science Inventory

    EPA announced the availability of the final report, The Effects of Mountaintop Mines and Valley Fills on Aquatic Ecosystems of the Central Appalachian Coalfields. This report assesses the state of the science on the environmental impacts of mountaintop mines and valley ...

  12. Projected Impacts of Climate, Urbanization, Water Management, and Wetland Restoration on Waterbird Habitat in California’s Central Valley

    PubMed Central

    Fleskes, Joseph P.

    2017-01-01

    The Central Valley of California is one of the most important regions for wintering waterbirds in North America despite extensive anthropogenic landscape modification and decline of historical wetlands there. Like many other mediterranean-climate ecosystems across the globe, the Central Valley has been subject to a burgeoning human population and expansion and intensification of agricultural and urban development that have impacted wildlife habitats. Future effects of urban development, changes in water supply management, and precipitation and air temperature related to global climate change on area of waterbird habitat in the Central Valley are uncertain, yet potentially substantial. Therefore, we modeled area of waterbird habitats for 17 climate, urbanization, water supply management, and wetland restoration scenarios for years 2006–2099 using a water resources and scenario modeling framework. Planned wetland restoration largely compensated for adverse effects of climate, urbanization, and water supply management changes on habitat areas through 2065, but fell short thereafter for all except one scenario. Projected habitat reductions due to climate models were more frequent and greater than under the recent historical climate and their magnitude increased through time. After 2065, area of waterbird habitat in all scenarios that included severe warmer, drier climate was projected to be >15% less than in the “existing” landscape most years. The greatest reduction in waterbird habitat occurred in scenarios that combined warmer, drier climate and plausible water supply management options affecting priority and delivery of water available for waterbird habitats. This scenario modeling addresses the complexity and uncertainties in the Central Valley landscape, use and management of related water supplies, and climate to inform waterbird habitat conservation and other resource management planning. Results indicate that increased wetland restoration and additional

  13. Projected impacts of climate, urbanization, water management, and wetland restoration on waterbird habitat in California’s Central Valley

    USGS Publications Warehouse

    Matchett, Elliott L.; Fleskes, Joseph

    2017-01-01

    The Central Valley of California is one of the most important regions for wintering waterbirds in North America despite extensive anthropogenic landscape modification and decline of historical wetlands there. Like many other mediterranean-climate ecosystems across the globe, the Central Valley has been subject to a burgeoning human population and expansion and intensification of agricultural and urban development that have impacted wildlife habitats. Future effects of urban development, changes in water supply management, and precipitation and air temperature related to global climate change on area of waterbird habitat in the Central Valley are uncertain, yet potentially substantial. Therefore, we modeled area of waterbird habitats for 17 climate, urbanization, water supply management, and wetland restoration scenarios for years 2006–2099 using a water resources and scenario modeling framework. Planned wetland restoration largely compensated for adverse effects of climate, urbanization, and water supply management changes on habitat areas through 2065, but fell short thereafter for all except one scenario. Projected habitat reductions due to climate models were more frequent and greater than under the recent historical climate and their magnitude increased through time. After 2065, area of waterbird habitat in all scenarios that included severe warmer, drier climate was projected to be >15% less than in the “existing” landscape most years. The greatest reduction in waterbird habitat occurred in scenarios that combined warmer, drier climate and plausible water supply management options affecting priority and delivery of water available for waterbird habitats. This scenario modeling addresses the complexity and uncertainties in the Central Valley landscape, use and management of related water supplies, and climate to inform waterbird habitat conservation and other resource management planning. Results indicate that increased wetland restoration and additional

  14. MANAGEMENT OF SMALL MAMMALS IN A RELICT GRASSLAND IN CALIFORNIA'S CENTRAL VALLEY

    Treesearch

    ANNE POOPATANAPONG; DOUGLAS A. KELT

    1999-01-01

    land-use patterns over the past century. In California's Central Valley these changes have resulted in replacement of native grassland vegetation by non-native annual grasses. Jepson Prairie is a natural reserve that has been set aside to preserve native vernal pool and bunchgrass habitats. Jepson Prairie also provides habitat for several state and federally...

  15. RELATIONSHIPS BETWEEN ENVIRONMENTAL VARIABLES AND BENTHIC DIATOM ASSEMBLAGES IN CALIFORNIA CENTRAL VALLEY STREAMS (USA)

    EPA Science Inventory

    Streams and rivers in the California Central Valley Ecoregion have been substantially modified by human activities. This study examines distributional patterns of benthic diatom assemblages in relation to environmental characteristics in streams and rivers of this region. Benthic...

  16. Predicted pH at the domestic and public supply drinking water depths, Central Valley, California

    USGS Publications Warehouse

    Rosecrans, Celia Z.; Nolan, Bernard T.; Gronberg, Jo Ann M.

    2017-03-08

    This scientific investigations map is a product of the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) project modeling and mapping team. The prediction grids depicted in this map are of continuous pH and are intended to provide an understanding of groundwater-quality conditions at the domestic and public supply drinking water zones in the groundwater of the Central Valley of California. The chemical quality of groundwater and the fate of many contaminants is often influenced by pH in all aquifers. These grids are of interest to water-resource managers, water-quality researchers, and groundwater modelers concerned with the occurrence of natural and anthropogenic contaminants related to pH. In this work, the median well depth categorized as domestic supply was 30 meters below land surface, and the median well depth categorized as public supply is 100 meters below land surface. Prediction grids were created using prediction modeling methods, specifically boosted regression trees (BRT) with a Gaussian error distribution within a statistical learning framework within the computing framework of R (http://www.r-project.org/). The statistical learning framework seeks to maximize the predictive performance of machine learning methods through model tuning by cross validation. The response variable was measured pH from 1,337 wells and was compiled from two sources: USGS National Water Information System (NWIS) database (all data are publicly available from the USGS: http://waterdata.usgs.gov/ca/nwis/nwis) and the California State Water Resources Control Board Division of Drinking Water (SWRCB-DDW) database (water quality data are publicly available from the SWRCB: http://www.waterboards.ca.gov/gama/geotracker_gama.shtml). Only wells with measured pH and well depth data were selected, and for wells with multiple records, only the most recent sample in the period 1993–2014 was used. A total of 1,003 wells (training dataset) were used to train the BRT

  17. Planned updates and refinements to the central valley hydrologic model, with an emphasis on improving the simulation of land subsidence in the San Joaquin Valley

    USGS Publications Warehouse

    Faunt, C.C.; Hanson, R.T.; Martin, P.; Schmid, W.

    2011-01-01

    California's Central Valley has been one of the most productive agricultural regions in the world for more than 50 years. To better understand the groundwater availability in the valley, the U.S. Geological Survey (USGS) developed the Central Valley hydrologic model (CVHM). Because of recent water-level declines and renewed subsidence, the CVHM is being updated to better simulate the geohydrologic system. The CVHM updates and refinements can be grouped into two general categories: (1) model code changes and (2) data updates. The CVHM updates and refinements will require that the model be recalibrated. The updated CVHM will provide a detailed transient analysis of changes in groundwater availability and flow paths in relation to climatic variability, urbanization, stream flow, and changes in irrigated agricultural practices and crops. The updated CVHM is particularly focused on more accurately simulating the locations and magnitudes of land subsidence. The intent of the updated CVHM is to help scientists better understand the availability and sustainability of water resources and the interaction of groundwater levels with land subsidence. ?? 2011 ASCE.

  18. Planned updates and refinements to the Central Valley hydrologic model with an emphasis on improving the simulation of land subsidence in the San Joaquin Valley

    USGS Publications Warehouse

    Faunt, Claudia C.; Hanson, Randall T.; Martin, Peter; Schmid, Wolfgang

    2011-01-01

    California's Central Valley has been one of the most productive agricultural regions in the world for more than 50 years. To better understand the groundwater availability in the valley, the U.S. Geological Survey (USGS) developed the Central Valley hydrologic model (CVHM). Because of recent water-level declines and renewed subsidence, the CVHM is being updated to better simulate the geohydrologic system. The CVHM updates and refinements can be grouped into two general categories: (1) model code changes and (2) data updates. The CVHM updates and refinements will require that the model be recalibrated. The updated CVHM will provide a detailed transient analysis of changes in groundwater availability and flow paths in relation to climatic variability, urbanization, stream flow, and changes in irrigated agricultural practices and crops. The updated CVHM is particularly focused on more accurately simulating the locations and magnitudes of land subsidence. The intent of the updated CVHM is to help scientists better understand the availability and sustainability of water resources and the interaction of groundwater levels with land subsidence.

  19. 75 FR 15453 - Central Valley Project Improvement Act, Westlands Water District Drainage Repayment Contract

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-29

    ... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act, Westlands Water District Drainage Repayment Contract AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of Proposed Repayment Contract. SUMMARY: The Bureau of Reclamation will be initiating negotiations with the...

  20. Atmospheric transport of organophosphate pesticides from California's Central Valley to the Sierra Nevada Mountains

    USGS Publications Warehouse

    Zabik, John M.; Seiber, James N.

    1993-01-01

    Atmospheric transport of organophosphate pesticides from California's Central Valley to the Sierra Nevada mountains was assessed by collecting air- and wet-deposition samples during December, January, February, and March, 1990 to 1991. Large-scale spraying of these pesticides occurs during December and January to control insect infestations in valley orchards. Sampling sites were placed at 114- (base of the foothills), 533-, and 1920-m elevations. Samples acquired at these sites contained chlorpyrifos [phosphorothioic acid; 0,0-diethyl 0-(3,5,6-trichloro-2-pyridinyl) ester], parathion [phosphorothioic acid, 0-0-diethylo-(4-nitrophenyl) ester], diazinon {phosphorothioic acid, 0,0-diethyl 0-[6-methyl-2-(1-methylethyl)-4-pyrimidinyl] ester} diazinonoxon {phosphoric acid, 0,0-diethyl 0-[6-methyl-2-(1-methylethyl)-4-pyrimidinyl] ester}, and paraoxon [phosphoric acid, 0,0-diethyl 0-(4-nitrophenyl) ester] in both air and wet deposition samples. Air concentrations of chloropyrifos, diazinon and parathion ranged from 13 to 13 000 pg/m3 at the base of the foothills. At 533-m air concentrations were below the limit of quantification (1.4 pg/m3) to 83 pg/m3 and at 1920 m concentrations were below the limit of quantification. Concentrations in wet deposition varied with distance and elevation from the Central Valley. Rainwater concentrations at the base of the foot hills ranged from 16 to 7600 pg/mL. At 533-m rain and snow water concentrations ranged from below the limit of quantification (1.3 pg/mL) to 140 pg/mL and at 1920 m concentrations ranged from below the limit of quantification to 48 pg/mL. These findings indicate that atmospheric transport of pesticides applied in the valley to the Sierra Nevada mountains is occurring, but the levels decrease as distance and elevation increase from the valley floor.

  1. Hydrogeologic Framework and Ground Water in Basin-Fill Deposits of the Diamond Valley Flow System, Central Nevada

    USGS Publications Warehouse

    Tumbusch, Mary L.; Plume, Russell W.

    2006-01-01

    The Diamond Valley flow system, an area of about 3,120 square miles in central Nevada, consists of five hydrographic areas: Monitor, Antelope, Kobeh, and Diamond Valleys and Stevens Basin. Although these five areas are in a remote part of Nevada, local government officials and citizens are concerned that the water resources of the flow system eventually could be further developed for irrigation or mining purposes or potentially for municipal use outside the study area. In order to better understand the flow system, the U.S. Geological Survey in cooperation with Eureka, Lander, and Nye Counties and the Nevada Division of Water Resources, is conducting a multi-phase study of the flow system. The principal aquifers of the Diamond Valley flow system are in basin-fill deposits that occupy structural basins comprised of carbonate rocks, siliciclastic sedimentary rocks, igneous intrusive rocks, and volcanic rocks. Carbonate rocks also function as aquifers, but their extent and interconnections with basin-fill aquifers are poorly understood. Ground-water flow in southern Monitor Valley is from the valley margins toward the valley axis and then northward to a large area of discharge by evapotranspiration (ET) that is formed south of a group of unnamed hills near the center of the valley. Ground-water flow from northern Monitor Valley, Antelope Valley, and northern and western parts of Kobeh Valley converges to an area of ground-water discharge by ET in central and eastern Kobeh Valley. Prior to irrigation development in the 1960s, ground-water flow in Diamond Valley was from valley margins toward the valley axis and then northward to a large discharge area at the north end of the valley. Stevens Basin is a small upland basin with internal drainage and is not connected with other parts of the flow system. After 40 years of irrigation pumping, a large area of ground-water decline has developed in southern Diamond Valley around the irrigated area. In this part of Diamond

  2. Predicting arsenic in drinking water wells of the Central Valley, California

    USGS Publications Warehouse

    Ayotte, Joseph; Nolan, Bernard T.; Gronberg, JoAnn M.

    2016-01-01

    Probabilities of arsenic in groundwater at depths used for domestic and public supply in the Central Valley of California are predicted using weak-learner ensemble models (boosted regression trees, BRT) and more traditional linear models (logistic regression, LR). Both methods captured major processes that affect arsenic concentrations, such as the chemical evolution of groundwater, redox differences, and the influence of aquifer geochemistry. Inferred flow-path length was the most important variable but near-surface-aquifer geochemical data also were significant. A unique feature of this study was that previously predicted nitrate concentrations in three dimensions were themselves predictive of arsenic and indicated an important redox effect at >10 μg/L, indicating low arsenic where nitrate was high. Additionally, a variable representing three-dimensional aquifer texture from the Central Valley Hydrologic Model was an important predictor, indicating high arsenic associated with fine-grained aquifer sediment. BRT outperformed LR at the 5 μg/L threshold in all five predictive performance measures and at 10 μg/L in four out of five measures. BRT yielded higher prediction sensitivity (39%) than LR (18%) at the 10 μg/L threshold–a useful outcome because a major objective of the modeling was to improve our ability to predict high arsenic areas.

  3. Field Scale Groundwater Nitrate Loading Model for the Central Valley, California, 1945-Current

    NASA Astrophysics Data System (ADS)

    Harter, T.; Dzurella, K.; Bell, A.; Kourakos, G.

    2015-12-01

    Anthropogenic groundwater nitrate contamination in the Central Valley aquifer system, California, is widespread, with over 40% of domestic wells in some counties exceeding drinking water standards. Sources of groundwater nitrate include leaky municipal wastewater systems, municipal wastewater recharge, onsite wastewater treatment (septic) systems, atmospheric nitrogen deposition, animal farming, application of organic waste materials (sludge, biosolids, animal manure) to agricultural lands, and synthetic fertilizer. At the site or field scale, nitrogen inputs to the landscape are balanced by plant nitrogen uptake and harvest, atmospheric nitrogen losses, surface runoff of nitrogen, soil nitrogen storage changes, and leaching to groundwater. Irrigated agriculture is a dominant player in the Central Valley nitrogen cycle: The largest nitrogen fluxes are synthetic fertilizer and animal manure applications to cropland, crop nitrogen uptake, and groundwater nitrogen losses. We construct a historic field/parcel scale groundwater nitrogen loading model distinguishing urban and residential areas, individual animal farming areas, leaky wastewater lagoons, and approximately 50 different categories of agricultural crops. For non-agricultural landuses, groundwater nitrate loading is based on reported leaching values, animal population, and human population. For cropland, groundwater nitrate loading is computed from mass balance, taking into account diverse and historically changing management practices between different crops. Groundwater nitrate loading is estimated for 1945 to current. Significant increases in groundwater nitrate loading are associated with the expansion of synthetic fertilizer use in the 1950s to 1970s. Nitrate loading from synthetic fertilizer use has stagnated over the past 20 years due to improvements in nutrient use efficiency. However, an unbroken 60 year exponential increase in dairy production until the late 2000s has significantly impacted the

  4. Waterbird habitat in California's Central Valley basins under climate, urbanization, and water management scenarios

    USGS Publications Warehouse

    Matchett, Elliott L.; Fleskes, Joseph

    2018-01-01

    California's Central Valley provides critical, but threatened habitat and food resources for migrating and wintering waterfowl, shorebirds, and other waterbirds. The Central Valley is comprised of nine basins that were defined by the Central Valley Joint Venture (CVJV) to assist in conservation planning. Basins vary in composition and extent of habitats, which primarily include croplands and wetlands that rely on water supplies shared with other competing human and environmental uses. Changes in climate, urban development, and water supply management are uncertain and could reduce future availability of water supplies supporting waterbird habitats and limit effectiveness of wetland restoration planned by the CVJV to support wintering waterbirds. We modeled 17 plausible scenarios including combinations of three climate projections, three urbanization rates, and five water supply management options to promote agricultural and urban water uses, with and without wetland restoration. Our research examines the reduction in quantity and quality of habitats during the fall migration-wintering period by basin under each scenario, and the efficacy of planned wetland restoration to compensate reductions in flooded areas of wetland habitats. Scenario combinations of projected climate, urbanization, and water supply management options reduced availability of flooded cropland and wetland habitats during fall-winter and degraded the quality of seasonal wetlands (i.e., summer-irrigation for improved forage production), though the extent and frequency of impacts varied by basin. Planned wetland restoration may substantially compensate for scenario-related effects on wetland habitats in each basin. However, results indicate that Colusa, Butte, Sutter, San Joaquin, and Tulare Basins may require additional conservation to support summer-irrigation of seasonal wetlands and winter-flooding of cropland habitats. Still further conservation may be required to provide sufficient areas of

  5. Central California Valley Ecoregion: Chapter 17 in Status and trends of land change in the Western United States--1973 to 2000

    USGS Publications Warehouse

    Sleeter, Benjamin M.

    2012-01-01

    The Central California Valley Ecoregion, which covers approximately 45,983 km2 (17,754 mi2), is an elongated basin extending approximately 650 km north to south through central California (fig. 1) (Omernik, 1987; U.S. Environmental Protection Agency, 1997). The ecoregion is surrounded entirely by the Southern and Central California Chaparral and Oak Woodlands Ecoregion, which includes parts of the Coast Ranges to the west and which is bounded by the Sierra Nevada to the east. The Central California Valley Ecoregion accounts for more than half of California’s agricultural production value and is one of the most important agricultural regions in the country, with flat terrain, fertile soils, a favorable climate, and nearly 70 percent of its land in cultivation (Kuminoff and others, 2000; Sumner and others, 2003). Commodities produced in the region include milk and dairy, cattle and calves, cotton, almonds, citrus, and grapes, among others (U.S. Department of Agriculture, 2004; Johnston and McCalla, 2004; Kuminoff and others, 2000) (figs. 2A,B,C). Six of the top eight agricultural-producing counties in California are located at least partly within the Central California Valley Ecoregion (Kuminoff and others, 2000) (table 1). The Central California Valley Ecoregion is also home to nearly 5 million people spread throughout the region, including the major cities of Sacramento (state capital), Fresno, Bakersfield, and Stockton, California (U.S. Census Bureau, 2000) (fig. 1).

  6. 75 FR 69698 - Central Valley Project Improvement Act, Criteria for Developing Refuge Water Management Plans

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-15

    ... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Central Valley Project Improvement Act, Criteria for Developing Refuge Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: The ``Criteria for Developing Refuge Water Management Plans'' (Refuge...

  7. Dating Caral, a preceramic site in the Supe Valley on the central coast of Peru.

    PubMed

    Solis, R S; Haas, J; Creamer, W

    2001-04-27

    Radiocarbon dates from the site of Caral in the Supe Valley of Peru indicate that monumental corporate architecture, urban settlement, and irrigation agriculture began in the Americas by 4090 years before the present (2627 calibrated years B.C.) to 3640 years before the present (1977 calibrated years B.C.). Caral is located 23 kilometers inland from the Pacific coast and contains a central zone of monumental, residential, and nonresidential architecture covering an area of 65 hectares. Caral is one of 18 large preceramic sites in the Supe Valley.

  8. Depth to water, 1991, in the Rathdrum Prairie, Idaho; Spokane River valley, Washington; Moscow-Lewiston-Grangeville area, Idaho; and selected intermontane valleys, east-central Idaho

    USGS Publications Warehouse

    Berenbrock, Charles E.; Bassick, M.D.; Rogers, T.L.; Garcia, S.P.

    1995-01-01

    This map report illustrates digitally generated depth-to-water zones for the Rathdrum Prairie in Idaho; part of the Spokane River Valley in eastern Washington; and the intermontane valleys of the upper Big Wood, Big Lost, Pahsimeroi, Little Lost, and Lemhi Rivers and Birch Creek in Idaho. Depth to water is 400 to 500 feet below land surface in the northern part of Rathdrum Prairie, 100 to 200 feet below land surface at the Idaho-Washington State line, and 0 to 250 feet below land surface in the Spokane area. Depth to water in the intermontane valleys in east-central Idaho is least (usually less than 50 feet) near streams and increases toward valley margins where mountain-front alluvial fans have formed. Depths to water shown in the Moscow-Lewiston-Grangeville area in Idaho are limited to point data at individual wells because most of the water levels measured were not representative of levels in the uppermost aquifer but of levels in deeper aquifers.

  9. Effects of Groundwater Development on Uranium: Central Valley, California, USA

    USGS Publications Warehouse

    Jurgens, Bryant C.; Fram, Miranda S.; Belitz, Kenneth; Burow, Karen R.; Landon, Matthew K.

    2009-01-01

    Uranium (U) concentrations in groundwater in several parts of the eastern San Joaquin Valley, California, have exceeded federal and state drinking water standards during the last 20 years. The San Joaquin Valley is located within the Central Valley of California and is one of the most productive agricultural areas in the world. Increased irrigation and pumping associated with agricultural and urban development during the last 100 years have changed the chemistry and magnitude of groundwater recharge, and increased the rate of downward groundwater movement. Strong correlations between U and bicarbonate suggest that U is leached from shallow sediments by high bicarbonate water, consistent with findings of previous work in Modesto, California. Summer irrigation of crops in agricultural areas and, to lesser extent, of landscape plants and grasses in urban areas, has increased Pco2 concentrations in the soil zone and caused higher temperature and salinity of groundwater recharge. Coupled with groundwater pumping, this process, as evidenced by increasing bicarbonate concentrations in groundwater over the last 100 years, has caused shallow, young groundwater with high U concentrations to migrate to deeper parts of the groundwater system that are tapped by public-supply wells. Continued downward migration of U-affected groundwater and expansion of urban centers into agricultural areas will likely be associated with increased U concentrations in public-supply wells. The results from this study illustrate the potential longterm effects of groundwater development and irrigation-supported agriculture on water quality in arid and semiarid regions around the world.

  10. Geothermal energy from deep sedimentary basins: The Valley of Mexico (Central Mexico)

    NASA Astrophysics Data System (ADS)

    Lenhardt, Nils; Götz, Annette E.

    2015-04-01

    The geothermal potential of the Valley of Mexico has not been addressed in the past, although volcaniclastic settings in other parts of the world contain promising target reservoir formations. A first assessment of the geothermal potential of the Valley of Mexico is based on thermophysical data gained from outcrop analogues, covering all lithofacies types, and evaluation of groundwater temperature and heat flow values from literature. Furthermore, the volumetric approach of Muffler and Cataldi (1978) leads to a first estimation of ca. 4000 TWh (14.4 EJ) of power generation from Neogene volcanic rocks within the Valley of Mexico. Comparison with data from other sedimentary basins where deep geothermal reservoirs are identified shows the high potential of the Valley of Mexico for future geothermal reservoir utilization. The mainly low permeable lithotypes may be operated as stimulated systems, depending on the fracture porosity in the deeper subsurface. In some areas also auto-convective thermal water circulation might be expected and direct heat use without artificial stimulation becomes reasonable. Thermophysical properties of tuffs and siliciclastic rocks qualify them as promising target horizons (Lenhardt and Götz, 2015). The here presented data serve to identify exploration areas and are valuable attributes for reservoir modelling, contributing to (1) a reliable reservoir prognosis, (2) the decision of potential reservoir stimulation, and (3) the planning of long-term efficient reservoir utilization. References Lenhardt, N., Götz, A.E., 2015. Geothermal reservoir potential of volcaniclastic settings: The Valley of Mexico, Central Mexico. Renewable Energy. [in press] Muffler, P., Cataldi, R., 1978. Methods for regional assessment of geothermal resources. Geothermics, 7, 53-89.

  11. Constrained Inclusion: Access and Persistence Among Undocumented Community College Students in California's Central Valley

    ERIC Educational Resources Information Center

    Negrón-Gonzales, Genevieve

    2017-01-01

    This article examines the ways in which citizenship status uniquely shapes both the access and persistence of undocumented community college students in the Central Valley of California. Drawing on more than 2 years of qualitative fieldwork, it is argued that undocumented community college students navigate an institutional landscape of…

  12. Barriers to Coverage of Transborder Environmental Issues in the Ferghana Valley of Central Asia

    ERIC Educational Resources Information Center

    Freedman, Eric

    2014-01-01

    Three former Soviet republics occupy Central Asia's Ferghana Valley, a region of serious transborder environmental problems, especially ones that involve water and energy. Most news organizations in Kyrgyzstan, Tajikistan, and Uzbekistan provide little in-depth coverage of these issues. Journalists in one country usually do not seek news sources…

  13. Mapping the Palaeo-Piniada Valley, Central Greece, Based on Systematic Microtremor Analyses

    NASA Astrophysics Data System (ADS)

    Mantovani, A.; Valkaniotis, S.; Rapti, D.; Caputo, R.

    2018-03-01

    The application of seismic noise-based techniques has become particularly popular in the last decades, as they are not invasive and do not require large teams or expensive equipments. The Horizontal to Vertical Spectral Ratio (HVSR) is commonly used not only in seismic microzoning studies as far as from noise recording constraining the fundamental resonant frequency, but it is also possible to infer the depth of the bedrock knowing the average shear wave velocity of the overlying sedimentary cover, or viceversa (i.e. resonance equation). For the purposes of the present research, more than 300 single-station noise measurements were carried out across the Piniada Valley (Central Greece), along and between several transects planned roughly perpendicular to the mean valley trend. To understand the palaeogeographic and tectonic evolution of this area, we needed an estimation of the geometry at depth of the bedrock underlying the fluvial deposits of the present-day Pinios River. As a result, for each measured site, we calculated the depth of the bedrock and, afterwards, such values were opportunely interpolated for obtaining a 3D model of the palaeo-Piniada Valley documenting for the first time the recent (Late Quaternary) inversion of the topographic gradient.

  14. Water budgets for major streams in the Central Valley, California, 1961-77

    USGS Publications Warehouse

    Mullen, J.R.; Nady, Paul

    1985-01-01

    A compilation of annual streamflow data for 20 major stream systems in the central Valley of California, for water years 1961-77, is presented. The water-budget tables list gaged and ungaged inflow from tributaries and canals, diversions, and gaged outflow. Theoretical outflow and gain or loss in a reach are computed. A schematic diagram and explanation of the data are provided for each water-budget table. (USGS)

  15. Geophysical Investigation of Avon Valley, West-Central Montana, using Gravity and Seismic Reflection Profiling

    NASA Astrophysics Data System (ADS)

    Knatterud, L.; Mosolf, J.; Speece, M. A.; Zhou, X.

    2014-12-01

    The Avon Valley and adjacent mountains in west-central Montana lie within the Lewis and Clark Line, a major system of WNW-striking faults and folds that transect the more northerly structural grain of the northern Rockies and represent alternating episodes of transtensional and transpressional deformation. The northwest-trending valley has been previously interpreted as an extensional half graben filled with Tertiary sedimentary and volcanic deposits; however, little-to-no geophysical constraints on basin architecture or the thickness of Tertiary fill have been reported. A major northwest-striking fault with significant normal displacement clearly bounds the valley to the northeast, juxtaposing Tertiary sedimentary deposits against Proterozoic-Mesozoic units deformed by shortening structures and crosscut by Cretaceous granitic intrusions. Tertiary volcanic deposits unconformably overlying faulted and folded Phanerozoic-Proterozoic sequences in the eastern Garnet Range bound the valley to the southwest, but in the past no faults had been mapped along this margin. New mapping by the Montana Bureau of Mines and Geology (MBMG) has identified a system of high-angle, northwest- and northeast-striking, oblique-slip faults along the southwest border of the Avon calling into question if the valley is a half, full, or asymmetrical graben. Geophysical data has recently been acquired by Montana Tech to help define the structural architecture of the Avon Valley and the thickness of its Tertiary fill. Gravity data and a short seismic reflection profile have been collected and a preliminary interpretation of these data indicates a half graben with a series of normal faults bounding the western side of the valley. Ongoing gravity data collection throughout 2014 should refine this interpretation by better defining the bedrock-Tertiary interface at depth.

  16. Quantifying large scale deformation and aquifer properties over Central Valley, California using a combination of InSAR, GPS and hydraulic head level data

    NASA Astrophysics Data System (ADS)

    Ojha, C.; Shirzaei, M.; Werth, S.; Argus, D. F.

    2016-12-01

    California's Central Valley is one of the largest productive agricultural regions in the world, which heavily relies on the underground water supply. As a result of pumping and recharge processes, the aquifer systems compact and expand, which is manifested in quasi-cyclic changes in the surface elevation and observations of hydraulic head levels. On the other hand, over last century, due to overdrafting of aquifer systems the volume of groundwater has substantially reduced, which causes irreversible decline in surface elevation. The aquifer storativity, characterizing the capacity of an aquifer to release groundwater, is affected by the excess vertical strain and permanent deformation. To quantify the capacity of the Central Valley aquifer systems to release fresh water, a valley-wide estimate of the storativity is required. Hence, we performed a joint analysis of large set of interferometric SAR and GPS data sets in conjunction with well data across the valley. In this context, we used L-band set of 420 ALOS-PALSAR SAR images. The data has been processed to generate 1604 SAR interferograms, using a pixel dimension of about 100 m x 100 m and imposing a maximum spatial and temporal baseline threshold of 2000 meter and 1500 days, respectively. In this study we rigorously integrate >500 permanent GPS stations and InSAR data to determine a time series of line of sight changes in a reference frame fixed to (CM) the center of mass of solid Earth. The result highlights an overall map of surface deformation over the entire Central valley region, due to interseismic strain accumulation along San Andreas fault system and compaction of aquifer systems. In the southern part of Central Valley i.e., San Joaquin Valley, which includes the San Joaquin and Tulare Basins, has experienced large changes in groundwater storage during the drought period. As a result, total land subsidence of 0.30-0.50 m has observed [Farr and Liu 2015], adjacent to creeping rate of 20-30 mm/year along

  17. Land use investigations in the central valley and central coastal test sites, California

    NASA Technical Reports Server (NTRS)

    Estes, J. E.

    1973-01-01

    The Geography Remote Sensing Unit (GRSU) at the University of California, Santa Barbara is responsible for investigations with ERTS-1 data in the Central Coastal Zone and West Side of the San Joaquin Valley. The nature of investigative effort involves the inventory, monitoring, and assessment of the natural and cultural resources of the two areas. Land use, agriculture, vegetation, landforms, geology, and hydrology are the principal subjects for attention. These parameters are the key indicators of the dynamically changing character of the areas. Monitoring of these parameters with ERTS-1 data will provide the techniques and methodologies required to generate the information needed by federal, state, county, and local agencies to assess change-related phenomena and plan for management and development.

  18. Effects of Groundwater Development on Uranium: Central Valley, California, USA

    USGS Publications Warehouse

    Jurgens, B.C.; Fram, M.S.; Belitz, K.; Burow, K.R.; Landon, M.K.

    2010-01-01

    Uranium (U) concentrations in groundwater in several parts of the eastern San Joaquin Valley, California, have exceeded federal and state drinking water standards during the last 20 years. The San Joaquin Valley is located within the Central Valley of California and is one of the most productive agricultural areas in the world. Increased irrigation and pumping associated with agricultural and urban development during the last 100 years have changed the chemistry and magnitude of groundwater recharge, and increased the rate of downward groundwater movement. Strong correlations between U and bicarbonate suggest that U is leached from shallow sediments by high bicarbonate water, consistent with findings of previous work in Modesto, California. Summer irrigation of crops in agricultural areas and, to lesser extent, of landscape plants and grasses in urban areas, has increased Pco2 concentrations in the soil zone and caused higher temperature and salinity of groundwater recharge. Coupled with groundwater pumping, this process, as evidenced by increasing bicarbonate concentrations in groundwater over the last 100 years, has caused shallow, young groundwater with high U concentrations to migrate to deeper parts of the groundwater system that are tapped by public-supply wells. Continued downward migration of U-affected groundwater and expansion of urban centers into agricultural areas will likely be associated with increased U concentrations in public-supply wells. The results from this study illustrate the potential long-term effects of groundwater development and irrigation-supported agriculture on water quality in arid and semiarid regions around the world. Journal compilation ?? 2009 National Ground Water Association. No claim to original US government works.

  19. A summary of ground-water pumpage in the Central Valley, California, 1961-77

    USGS Publications Warehouse

    Diamond, Jonathan; Williamson, A.K.

    1983-01-01

    In the Central Valley of California, a great agricultural economy has been developed in a semiarid environment. This economy is supported by imported surface water and 9 to 15 million acre-feet per year of ground water. Estimates of ground-water pumpage computed from power consumption have been compiled and summarized. Under ideal conditions, the accuracy of the methods used is about 3 percent. This level of accuracy is not sustained over the entire study area. When pumpage for the entire area is mapped, the estimates seem to be consistent areally and through time. A multiple linear-regression model was used to synthesize data for the years 1961 through 1977, when power data were not available. The model used a relation between ground-water pumpage and climatic indexes to develop a full suite of pumpage data to be used as input to a digital ground-water model, one of the products of the Central Valley Aquifer Project. Statistical analysis of well-perforation data from drillers ' logs and water-temperature data was used to determine the percentage of pumpage that was withdrawn from each of two horizontal layers. (USGS)

  20. Drought Impacts on Agricultural Production and Land Fallowing in California's Central Valley in 2015

    NASA Technical Reports Server (NTRS)

    Rosevelt, Carolyn; Melton, Forrest S.; Johnson, Lee; Guzman, Alberto; Verdin, James P.; Thenkabail, Prasad S.; Mueller, Rick; Jones, Jeanine; Willis, Patrick

    2016-01-01

    The ongoing drought in California substantially reduced surface water supplies for millions of acres of irrigated farmland in California's Central Valley. Rapid assessment of drought impacts on agricultural production can aid water managers in assessing mitigation options, and guide decision making with respect to mitigation of drought impacts. Satellite remote sensing offers an efficient way to provide quantitative assessments of drought impacts on agricultural production and increases in fallow acreage associated with reductions in water supply. A key advantage of satellite-based assessments is that they can provide a measure of land fallowing that is consistent across both space and time. We describe an approach for monthly and seasonal mapping of uncultivated agricultural acreage developed as part of a joint effort by USGS, USDA, NASA, and the California Department of Water Resources to provide timely assessments of land fallowing during drought events. This effort has used the Central Valley of California as a pilot region for development and testing of an operational approach. To provide quantitative measures of uncultivated agricultural acreage from satellite data early in the season, we developed a decision tree algorithm and applied it to time-series data from Landsat TM (Thematic Mapper), ETM+ (Enhanced Thematic Mapper Plus), OLI (Operational Land Imager), and MODIS (Moderate Resolution Imaging Spectroradiometer). Our effort has been focused on development of indicators of drought impacts in the March-August timeframe based on measures of crop development patterns relative to a reference period with average or above average rainfall. To assess the accuracy of the algorithms, monthly ground validation surveys were conducted across 650 fields from March-September in 2014 and 2015. We present the algorithm along with updated results from the accuracy assessment, and data and maps of land fallowing in the Central Valley in 2015.

  1. Drought Impacts on Agricultural Production and Land Fallowing in California's Central Valley in 2015

    NASA Astrophysics Data System (ADS)

    Rosevelt, C.; Melton, F. S.; Johnson, L.; Guzman, A.; Verdin, J. P.; Thenkabail, P. S.; Mueller, R.; Jones, J.; Willis, P.

    2015-12-01

    The ongoing drought in California substantially reduced surface water supplies for millions of acres of irrigated farmland in California's Central Valley. Rapid assessment of drought impacts on agricultural production can aid water managers in assessing mitigation options, and guide decision making with respect to mitigation of drought impacts. Satellite remote sensing offers an efficient way to provide quantitative assessments of drought impacts on agricultural production and increases in fallow acreage associated with reductions in water supply. A key advantage of satellite-based assessments is that they can provide a measure of land fallowing that is consistent across both space and time. We describe an approach for monthly and seasonal mapping of uncultivated agricultural acreage developed as part of a joint effort by USGS, USDA, NASA, and the California Department of Water Resources to provide timely assessments of land fallowing during drought events. This effort has used the Central Valley of California as a pilot region for development and testing of an operational approach. To provide quantitative measures of uncultivated agricultural acreage from satellite data early in the season, we developed a decision tree algorithm and applied it to timeseries of data from Landsat TM, ETM+, OLI, and MODIS. Our effort has been focused on development of indicators of drought impacts in the March - August timeframe based on measures of crop development patterns relative to a reference period with average or above average rainfall. To assess the accuracy of the algorithms, monthly ground validation surveys were conducted across 650 fields from March - September in 2014 and 2015. We present the algorithm along with updated results from the accuracy assessment, and data and maps of land fallowing in the Central Valley in 2015.

  2. Efficient crop type mapping based on remote sensing in the Central Valley, California

    NASA Astrophysics Data System (ADS)

    Zhong, Liheng

    Most agricultural systems in California's Central Valley are purposely flexible and intentionally designed to meet the demands of dynamic markets. Agricultural land use is also impacted by climate change and urban development. As a result, crops change annually and semiannually, which makes estimating agricultural water use difficult, especially given the existing method by which agricultural land use is identified and mapped. A minor portion of agricultural land is surveyed annually for land-use type, and every 5 to 8 years the entire valley is completely evaluated. So far no effort has been made to effectively and efficiently identify specific crop types on an annual basis in this area. The potential of satellite imagery to map agricultural land cover and estimate water usage in the Central Valley is explored. Efforts are made to minimize the cost and reduce the time of production during the mapping process. The land use change analysis shows that a remote sensing based mapping method is the only means to map the frequent change of major crop types. The traditional maximum likelihood classification approach is first utilized to map crop types to test the classification capacity of existing algorithms. High accuracy is achieved with sufficient ground truth data for training, and crop maps of moderate quality can be timely produced to facilitate a near-real-time water use estimate. However, the large set of ground truth data required by this method results in high costs in data collection. It is difficult to reduce the cost because a trained classification algorithm is not transferable between different years or different regions. A phenology based classification (PBC) approach is developed which extracts phenological metrics from annual vegetation index profiles and identifies crop types based on these metrics using decision trees. According to the comparison with traditional maximum likelihood classification, this phenology-based approach shows great advantages

  3. Down in the Valley: Trajectories of Injection Initiation among Young Injectors in California’s Central Valley

    PubMed Central

    Syvertsen, Jennifer L.; Paquette, Catherine E.; Pollini, Robin A.

    2017-01-01

    Background Injection drug use initiation represents a critical point of public health intervention, as injection increases risk forblood borne infections including Hepatitis C and HIV. In this paper, weexplore pathways to injection initiation among youth (<=30) in the ruralcontext of California’s Central Valley, where rates of injection drug useare among the highest in the nation. Methods We draw on semi-structured qualitative interviews with 20 younginjectors to examine drug use histories, including the factors that participants associated with their transition to injection drug use. Results The average age was 24.7 years (range: 20–30), 45% were female(n=9), and 30% were Latino (n=6). Participants described a variety ofpathways to injection, culminating in a first injection that involvedeither opioids (n=12) or methamphetamine (n=8). Among the opioid group, the majority used prescription opioids before transitioning to injection, while a smaller number transitioned to opioid injection from non-opioid recreational drug use. Injectors who first used prescription opioidsoften described growing up in affluent suburban areas and transitioned toinjection with peers, owing to a combination of factors related toindividual tolerance, cost, and shifting drug markets. In contrast, methamphetamine initiates grew up in less affluent families withhistories of substance use that exposed them to drugs at an early age. Methamphetamine users transitioned from smoking and snorting toinjection, often with family members or intimate partners, within broadercontexts of social disadvantage and stress. Conclusions While much of the focus on young injectors has centered onthe current opioid epidemic, our data suggest a need to consider multiple pathways toward injection initiation of different drugs. Targetedinterventions addressing the unique injection transition contexts of bothopioids and methamphetamine are urgently needed in the Central Valley ofCalifornia. PMID:28458170

  4. Air-quality bioindication in the greater central valley of California, with epiphytic macrolichen communities.

    Treesearch

    Sarah Jovan; Bruce McCune

    2005-01-01

    Air-quality monitoring in the United States is typically focused on urban areas even though the detrimental effects of pollution often extend into surrounding ecosystems. The purpose of this study was to construct a model, based upon epiphytic macrolichen community data, to indicate air-quality and climate in forested areas throughout the greater Central Valley of...

  5. Community and edaphic analysis of mixed oak forests in the ridge and valley province of central Pennsylvania

    Treesearch

    G.J. Nowacki; M.D. Abrams

    1991-01-01

    Forty-two relatively undisturbed mixed oak stands on nine different physiographic units in the Ridge and Valley Province of central Pennsylvania were surveyed to investigate the ecological status of oak species in the region.

  6. Aeromagnetic maps with geologic interpretations for the Tularosa Valley, south-central New Mexico

    USGS Publications Warehouse

    Bath, G.D.

    1977-01-01

    An aeromagnetic survey of the Tularosa Valley in south-central New Mexico has provided information on the igneous rocks that are buried beneath alluvium and colluvium. The data, compiled as residual magnetic anomalies, are shown on twelve maps at a scale of 1:62,500. Measurements of magnetic properties of samples collected in the valley and adjacent highlands give a basis for identifying the anomaly-producing rocks. Precambrian rocks of the crystalline basement have weakly induced magnetizations and produce anomalies having low magnetic intensities and low magnetic gradients. Late Cretaceous and Cenozoic intrusive rocks have moderately to strongly induced magnetizations. Precambrian rocks produce prominent magnetic anomalies having higher amplitudes and higher gradients. The Quaternary basalt has a strong remanent magnetization of normal polarity and produces narrow anomalies having high-magnetic gradients. Interpretations include an increase in elevation to the top of buried Precambrian rock in the northern part of the valley, a large Late Cretaceous and Cenozoic intrusive near Alamogordo, and a southern extension of the intrusive rock exposed in the Jarilla Mountains. Evidence for the southern extension comes from a quantitative analysis of the magnetic anomalies..

  7. Sacramento Valley, CA, USA

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The Sacramento Valley (40.5N, 121.5W) of California is the northern extension of the Central Valley, main agriculture region of the state. Hundreds of truck farms, vineyards and orchards can be seen throughout the length and breadth of the valley which was reclaimed from the desert by means of intensive and extensive irrigation projects.

  8. Hematology and plasma biochemistry values for the giant garter snake (Thamnophis gigas) and valley garter snake (Thamnophis sirtalis fitchi) in the Central Valley of California.

    PubMed

    Wack, Raymund F; Hansen, Eric; Small, Marilyn; Poppenga, Robert; Bunn, David; Johnson, Christine K

    2012-04-01

    Hematology and plasma biochemistry parameters are useful in the assessment and management of threatened and endangered species. Although reference ranges are readily available for many mammalian species, reference ranges for snakes are lacking for most species. We determined hematology and plasma biochemistry reference ranges for giant garter snakes (Thamnophis gigas) and valley garter snakes (Thamnophis sirtalis fitchi) living in four management areas in the Central Valley of California. White blood cell, heterophil, lymphocyte, and azurophil counts in giant garter snakes were approximately twice the values of valley garter snakes. Statistically significant differences in aspartate aminotransferase, globulin, and potassium between the two species did not appear clinically significant. No significant differences were found in the measured parameters between male and female giant garter snakes. Some differences were found among collection sites. These reference ranges provide baseline data for comparisons over time and between collection sites.

  9. Prevalence of hepatitis B infection among young and unsuspecting Hmong blood donors in the Central California Valley.

    PubMed

    Sheikh, Muhammad Y; Atla, Pradeep R; Raoufi, Rahim; Sadiq, Humaira; Sadler, Patrick C

    2012-02-01

    Chronic hepatitis B virus (HBV) infection may result in cirrhosis and/or hepatocellular carcinoma and is one of the leading causes of mortality in Asian Americans including Hmong Americans. The Central California Valley is home to a huge Hmong population. To date, the true prevalence of HBV among Hmong is largely unknown. The aim of this study was to contribute to the limited data on HBV prevalence and its trends in Hmong population in the Central California Valley. Between fiscal years 2006 and 2010, a total of 219, 450 voluntary donors were identified at Central California Blood Center in Fresno. Of these, 821 (399 males and 422 females) were Hmong donors. A cross-sectional review of the HBV (hepatitis B surface antigen) positivity among all donors was carried out. Prevalence estimates with 95% confidence intervals (CI) were calculated. Ninety-two percent of Hmong donors were between age groups 16 and 35 years, and only 8% were ≥36 years. The overall prevalence in Hmong was noted at 3.41% (95%CI 2.3-4.9) compared to 0.06% (95%CI 0.05-0.07) in donors of all ethnicities. The calculated prevalence could be an underestimate of the true HBV prevalence in Hmong as the study enrolled only healthy blood donors with predominant younger age (≤35 years) population. These results underscore the persistent burden of HBV infection and potentially increased risk of premature death even in the second generation Hmong community of the Central California Valley. This study reemphasizes the unequivocal need to develop robust preventive and treatment strategies for HBV in Hmong community.

  10. Mapping geodiversity and cultural heritage; a case study: Aït Bou Oulli valley in central High-Atlas, Morocco.

    NASA Astrophysics Data System (ADS)

    Bouzekraoui, Hicham; Barakat, Ahmed; El Youssi, Mohammed; El Khalki, Yahia; Hafid, Abdelatif; Mouaddine, Atika

    2016-04-01

    Central High-Atlas mountain in the centre of Morocco, contains an exceptional geodiversity. Some geomorphological and geological objects of it are included and protected recently by the World Heritage list. The valley of Aït Bou Oulli is located in the heart of the Moroccan central High-Atlas, whose height is 4068 m in Ighil M'goun and 3800 m in Rat Mountain. The mountain areas are characterized by higher geodiversity in comparison with other areas. The valley possesses a geological and geomorphological heritage which is very rich, much diversified and exceptional landscapes of high mountains. It is part of geopark M'Goun; the valley attracts a number of tourists every year. However, this number remains restricted because of the lack of the tools of promotion, valuation and mediation of this geoheritage. Moreover, the touristic infrastructure is modest. Regarding this situation, the geotouristic map appears as a tool of promotion of the geotourism and diversification of the regional and national tourist product. This work aims at elaborating new maps of geomorphosites, cultural sites, and geomonuments in high Mountain landscapes of the valley, suggested in geotourism circuits. The first results reveal the low exploitation of the geodiversity of this valley-oasis: the spectacular waterfalls, water sources, canyons, glacial cirques and U-shaped valleys, superficial karstic forms (sinkholes and swallow-holes), high-Atlas peaks and cliffs, spectacular scree slopes, badlands landscapes, fairy chimneys, and the geological history dating back to the Paleozoic and angular unconformity. In addition, the valley has diverse tangible cultural heritage spanning hundreds of years such as the enigmatic rock engravings (dating from 2000 to 3000 years), troglodyte caves and terraced agriculture landscapes, geomonuments (old cooperative storage, Kasbah, traditional water mills) and the architecture of the villages. It has also an intangible cultural heritage such as folklore. This

  11. Mapping Drought Impacts on Agricultural Production in California's Central Valley

    NASA Astrophysics Data System (ADS)

    Melton, F. S.; Guzman, A.; Johnson, L.; Rosevelt, C.; Verdin, J. P.; Dwyer, J. L.; Mueller, R.; Zakzeski, A.; Thenkabail, P. S.; Wallace, C.; Jones, J.; Windell, S.; Urness, J.; Teaby, A.; Hamblin, D.; Post, K. M.; Nemani, R. R.

    2014-12-01

    The ongoing drought in California has substantially reduced surface water supplies for millions of acres of irrigated farmland in California's Central Valley. Rapid assessment of drought impacts on agricultural production can aid water managers in assessing mitigation options, and guide decision making with respect to requests for local water transfers, county drought disaster designations, and allocation of emergency funds to mitigate drought impacts. Satellite remote sensing offers an efficient way to provide quantitative assessments of drought impacts on agricultural production and increases in idle acreage associated with reductions in water supply. A key advantage of satellite-based assessments is that they can provide a measure of land fallowing that is consistent across both space and time. We describe an approach for monthly and seasonal mapping of uncultivated agricultural acreage developed as part of a joint effort by USGS, USDA, NASA, and the California Department of Water Resources to provide timely assessments of land fallowing during drought events. This effort has used the Central Valley of California as a pilot region for development and testing of an operational approach. To provide quantitative measures of uncultivated agricultural acreage from satellite data early in the season, we developed a decision tree algorithm and applied it to timeseries of data from Landsat TM, ETM+, OLI, and MODIS. Our effort has been focused on development of indicators of drought impacts in the March - August timeframe based on measures of crop development patterns relative to a reference period with average or above average rainfall. To assess the accuracy of the algorithms, monthly ground validation surveys were conducted across 640 fields from March - September, 2014. We present the algorithm along with updated results from the accuracy assessment, and discuss potential applications to other regions.

  12. Sacramento Valley, CA, USA

    NASA Image and Video Library

    1973-06-22

    SL2-04-179 (22 June 1973) --- The Sacramento Valley (40.5N, 121.5W) of California is the northern extension of the Central Valley, main agriculture region of the state. Hundreds of truck farms, vineyards and orchards can be seen throughout the length and breadth of the valley which was reclaimed from the desert by means of intensive and extensive irrigation projects. Photo credit: NASA

  13. Buried paleoindian-age landscapes in stream valleys of the central plains, USA

    USGS Publications Warehouse

    Mandel, R.D.

    2008-01-01

    A systematic study of late-Quaternary landscape evolution in the Central Plains documented widespread, deeply buried paleosols that represent Paleoindian-age landscapes in terrace fills of large streams (> 5th order), in alluvial fans, and in draws in areas of western Kansas with a thick loess mantle. Alluvial stratigraphic sections were investigated along a steep bio-climatic gradient extending from the moist-subhumid forest-prairie border of the east-central Plains to the dry-subhumid and semi-arid shortgrass prairie of the west-central Plains. Radiocarbon ages indicate that most large streams were characterized by slow aggradation accompanied by cumulic soil development from ca. 11,500 to 10,000??14C yr B.P. In the valleys of some large streams, such as the Ninnescah and Saline rivers, these processes continued into the early Holocene. The soil-stratigraphic record in the draws of western Kansas indicates slow aggradation punctuated by episodes of landscape stability and pedogenesis beginning as early as ca. 13,300??14C yr B.P. and spanning the Pleistocene-Holocene boundary. The development record of alluvial fans in western Kansas is similar to the record in the draws; slow aggradation was punctuated by multiple episodes of soil development between ca. 13,000 and 9000??14C yr B.P. In eastern Kansas and Nebraska, development of alluvial fans was common during the early and middle Holocene, but evidence shows fan development as early as ca. 11,300??14C yr B.P. Buried soils dating between ca. 12,600 and 9000??14C yr B.P. were documented in fans throughout the region. In stream valleys across the Central Plains, rapid alluviation after ca. 9000??14C yr B.P. resulted in deeply buried soils that may harbor Paleoindian cultural deposits. Hence, the paucity of recorded stratified Paleoindian sites in the Central Plains is probably related to poor visibility (i.e., deep burial in alluvial deposits) instead of limited human occupation in the region during the terminal

  14. Hydrology of the San Luis Valley, south-central Colorado

    USGS Publications Warehouse

    Emery, P.A.; Boettcher, A.J.; Snipes, R.J.; Mcintyre, H.J.

    1969-01-01

    An investigation of the water resources of the Colorado part of the San Luis Valley was begun in 1966 by the U.S. Geological Survey, in cooperation with the Colorado Water Conservation Board. (See index map, fig. 1). The purpose of the investigation is to provide information for planning and implementing improved water-development and management practices. The major water problems in the San Luis Valley include (1) waterlogging, (2) waste of water by nonbeneficial evapotranspiration, (3) deterioration of ground-water chemical quality, and (4) failure of Colorado to deliver water to New Mexico and Texas in accordance with the Rio Grande Compact. This report describes the hydrologic environment, extent of water-resource development, and some of the problems related to that development. Information presented is based on data collected from 1966 to 1968 and on previous studies. Subsequent reports are planned as the investigation progresses. The San Luis Valley extends about 100 miles from Poncha Pass near the northeast corner of Saguache County, Colo., to a point about 16 miles south of the Colorado-New Mexico State line. The total area is 3,125 square miles, of which about 3,000 are in Colorado. The valley is nearly flat except for the San Luis Hills and a few other small areas. The Colorado part of the San Luis Valley, which is described in this report, has an average altitude of about 7,700 feet. Bounding the valley on the west are the San Juan Mountains and on the east the Sangre de Cristo Mountains. Most of the valley floor is bordered by alluvial fans deposited by streams originating in the mountains, the most extensive being the Rio Grande fan (see block diagram, fig. 2 in pocket). Most of the streamflow is derived from snowmelt from 4,700 square miles of watershed in the surrounding mountains. The northern half of the San Luis Valley is internally drained and is referred to as the closed basin. The lowest part of this area is known locally as the "sump." The

  15. Prostate Cancer and Pesticide Exposure in Diverse Populations in California’s Central Valley

    DTIC Science & Technology

    2008-12-01

    2.38 23.21 153 Control 15 years prior to DX 0.62 1.58 10.78 143 Benzimidazole Benomyl DX Year 0.28 1.57 15.82 163 1974 - 1999 0.60 1.77...prostate cancer with exposure to Benzimidazole Benomyl in California’s Central Valley 2005 - 2006 Benzimidazole Benomyl Frequency...associated with exposure to methyl bromide, captan, simazine, organochlorine group, paraquat dichloride and benzimidazole benomyl, after adjusting for

  16. Hydrogeologic framework and occurrence, movement, and chemical characterization of groundwater in Dixie Valley, west-central Nevada

    USGS Publications Warehouse

    Huntington, Jena M.; Garcia, C. Amanda; Rosen, Michael R.

    2014-01-01

    Dixie Valley, a primarily undeveloped basin in west-central Nevada, is being considered for groundwater exportation. Proposed pumping would occur from the basin-fill aquifer. In response to proposed exportation, the U.S. Geological Survey, in cooperation with the Bureau of Reclamation and Churchill County, conducted a study to improve the understanding of groundwater resources in Dixie Valley. The objective of this report is to characterize the hydrogeologic framework, the occurrence and movement of groundwater, the general water quality of the basin-fill aquifer, and the potential mixing between basin-fill and geothermal aquifers in Dixie Valley. Various types of geologic, hydrologic, and geochemical data were compiled from previous studies and collected in support of this study. Hydrogeologic units in Dixie Valley were defined to characterize rocks and sediments with similar lithologies and hydraulic properties influencing groundwater flow. Hydraulic properties of the basin-fill deposits were characterized by transmissivity estimated from aquifer tests and specific-capacity tests. Groundwater-level measurements and hydrogeologic-unit data were combined to create a potentiometric surface map and to characterize groundwater occurrence and movement. Subsurface inflow from adjacent valleys into Dixie Valley through the basin-fill aquifer was evaluated using hydraulic gradients and Darcy flux computations. The chemical signature and groundwater quality of the Dixie Valley basin-fill aquifer, and potential mixing between basin-fill and geothermal aquifers, were evaluated using chemical data collected from wells and springs during the current study and from previous investigations. Dixie Valley is the terminus of the Dixie Valley flow system, which includes Pleasant, Jersey, Fairview, Stingaree, Cowkick, and Eastgate Valleys. The freshwater aquifer in the study area is composed of unconsolidated basin-fill deposits of Quaternary age. The basin-fill hydrogeologic unit

  17. Minor and Trace Element Chemistry of Urban NS-Soot from the Central Valley of CA, USA

    NASA Astrophysics Data System (ADS)

    Kleich, S. J.; Hooper, R.

    2017-12-01

    During a recent study of metal transport in the Central Valley of California, it was noted that ns-soot (soot) occurred as complex clusters of graphene-like spheres admixed with other aerosols and were usually the dominant component of PM2.5 air particulates. These soot clusters contained a wide variety of metals of environmental concern such as As,Pb,Cr, and Ni. This study reports semi-quantitative results for 20 minor and trace elements (calibrated with Smithsonian microbeam standards) using a 200kV Transmission Electron Microscope, EDS, and SAED. This study also examined the mineralogy and crystallinity of admixed aerosols within composite soot clusters. Samples selected represent three contrasting urban settings in the Central Valley: Woodland, on the western side of the valley (Interstate highway to the east); Stockton, an inland sea-port and land transportation corridor in the center of the valley; and Roseville, a major rail-transport hub to the east. The wet/dry Mediterranean climate of California resulted in pronounced seasonal variations in total metal content. Soot cluster chemistry is highly variable however certain patterns emerged. Soot collected during the wet season is generally more aciniform, less structurally complex, and had lower sulfur (sulfate) concentrations but still had significant levels of transition metals (V,Cr,Mn,Fe,Ni,Zn and Pb) . Dry season soot was predominantly admixed with sulfate aerosols, and enriched in alkalis and alkaline earth metals. Stockton (wet-season) soot had up to 6000ppm of Pb. There is appreciable Pb (210ppm-2600ppm) in 38% of samples from Roseville but no Pb greater than 200ppm in Woodland. The highest overall total metals were found in Roseville soot with appreciable As(670ppm), V(100ppm), Pb(2600ppm), Zn(4000 ppm), Cr(90ppm), and Ni(300ppm). Heavy transport (road/rail/port) correlates with higher metal contents regardless of climate.

  18. Influence of the Institutional Structure of Surface Water Rights on Agricultural Production in the Central Valley

    NASA Astrophysics Data System (ADS)

    Nelson, K.; Burchfield, E. K.

    2017-12-01

    California's Central Valley region is one of the most productive agricultural systems on the planet. The high levels of agricultural production in this region require large amounts of fresh water for irrigation. However, the long-term availability of water required to sustain such levels of agricultural production has been questioned following the latest drought in California. In this study, we use Bayesian multilevel spatiotemporal modeling techniques to examine the influence of the institutional structure of surface water rights in the Central Valley on agricultural production during the recent drought. The R-INLA package is employed to account for spatial processes that have the potential to influence the effects of water right structures on crop productivity as well as on extent of cultivation. Model results suggest that seniority in surface water access significantly improves crop productivity on cultivated lands, but does not directly affect the ability to maintain cultivated extent. In addition, results suggest that areas with more junior surface water rights tend to reduce extent of cultivation, but maintain crop productivity, as cumulative drought stress increases.

  19. Seroprevalence of Hepatitis B and C Infections among Healthy Volunteer Blood Donors in the Central California Valley.

    PubMed

    Sheikh, Muhammad Y; Atla, Pradeep R; Ameer, Adnan; Sadiq, Humaira; Sadler, Patrick C

    2013-01-01

    The Central California Valley has a diverse population with significant proportions of Hispanics and Asians. This cross-sectional study was conducted to evaluate the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) in healthy blood donors in the Valley. A total of 217,738 voluntary blood donors were identified between 2006 and 2010 (36,795 first-time donors; 180,943 repeat donors). Among the first-time donors, the HBV and HCV prevalence was 0.28% and 0.52%, respectively. Higher HBV prevalence seen in Asians (3%) followed by Caucasians (0.05%), African Americans (0.15%), and Hispanics (0.05%). Hmong had a HBV prevalence of 7.63% with a peak prevalence of 8.76% among the 16- to 35-year-old age group. Highest HCV prevalence in Native Americans (2.8) followed by Caucasians (0.59%), Hispanics (0.45%), African Americans (0.38%), and Asians (0.2%). Ethnic disparities persist with regard to the prevalence of HBV and HCV in the Central California Valley. The reported prevalence may be an underestimate because our study enrolled healthy volunteer blood donors only. The development of aggressive public health measures to evaluate the true prevalence of HBV and HCV and to identify those in need of HBV and HCV prevention measures and therapy is critically important.

  20. Seroprevalence of Hepatitis B and C Infections among Healthy Volunteer Blood Donors in the Central California Valley

    PubMed Central

    Atla, Pradeep R.; Ameer, Adnan; Sadiq, Humaira; Sadler, Patrick C.

    2013-01-01

    Background/Aims The Central California Valley has a diverse population with significant proportions of Hispanics and Asians. This cross-sectional study was conducted to evaluate the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) in healthy blood donors in the Valley. Methods A total of 217,738 voluntary blood donors were identified between 2006 and 2010 (36,795 first-time donors; 180,943 repeat donors). Results Among the first-time donors, the HBV and HCV prevalence was 0.28% and 0.52%, respectively. Higher HBV prevalence seen in Asians (3%) followed by Caucasians (0.05%), African Americans (0.15%), and Hispanics (0.05%). Hmong had a HBV prevalence of 7.63% with a peak prevalence of 8.76% among the 16- to 35-year-old age group. Highest HCV prevalence in Native Americans (2.8) followed by Caucasians (0.59%), Hispanics (0.45%), African Americans (0.38%), and Asians (0.2%). Conclusions Ethnic disparities persist with regard to the prevalence of HBV and HCV in the Central California Valley. The reported prevalence may be an underestimate because our study enrolled healthy volunteer blood donors only. The development of aggressive public health measures to evaluate the true prevalence of HBV and HCV and to identify those in need of HBV and HCV prevention measures and therapy is critically important. PMID:23423771

  1. Texture and depositional history of near-surface alluvial deposits in the central part of the western San Joaquin Valley, California

    USGS Publications Warehouse

    Laudon, Julie; Belitz, Kenneth

    1989-01-01

    Saline conditions and associated high levels of selenium and other soluble trace elements in soil, shallow ground water, and agricultural drain water of the western San Joaquin Valley, California, have prompted a study of the texture of near-surface alluvial deposits in the central part of the western valley. Texture is characterized by the percentage of coarse-grained sediment present within a specified subsurface depth interval and is used as a basis for mapping the upper 50 feet of deposits. Resulting quantitative descriptions of the deposits are used to interpret the late Quaternary history of the area. Three hydrogeologic units--Coast Range alluvium, flood-basin deposits, and Sierran sand--can be recognized in the upper 50 feet of deposits in the central part of the western San Joaquin Valley. The upper 30 feet of Coast Range alluvium and the adjacent 5 to 35 feet of flood-basin deposits are predominantly fine grained. These fine-grained Coast Range deposits are underlain by coarse-grained channel deposits. The fine-grained flood basin deposits are underlain by coarse-grained Sierran sand. The extent and orientation of channel deposits below 20 feet in the Coast Range alluvium indicate that streams draining the Coast Range may have been tributary to the axial stream that deposited the Sierran sand and that streamflow may have been to the southeast. The fining-upward stratigraphic sequence in the upper 50 feet of deposits and the headward retreat of tributary stream channels from the valley trough with time support a recent hypothesis of climatic control of alluviation in the western San Joaquin Valley.

  2. Field Surveys, IOC Valleys. Volume III, Part II. Cultural Resources Survey, Pine and Wah Wah Valleys, Utah.

    DTIC Science & Technology

    1981-08-01

    valleys are typical of the Basin and Range Province, characterized by parallel, north-south trending mountain ranges, separated by hydrologically closed... basins . Pine and Wah Wah valleys each have hardpan-playas in their lowest areas. State Highway 21 runs roughly northwest-southeast through both val...have been important for prehis- toric and historic use of the area. Pine Valley: Pine and Wah Wah valleys are closed alluvial basins . The central part

  3. Fish communities of the Sacramento River Basin: Implications for conservation of native fishes in the Central Valley, California

    USGS Publications Warehouse

    May, J.T.; Brown, L.R.

    2002-01-01

    The associations of resident fish communities with environmental variables and stream condition were evaluated at representative sites within the Sacramento River Basin, California between 1996 and 1998 using multivariate ordination techniques and by calculating six fish community metrics. In addition, the results of the current study were compared with recent studies in the San Joaquin River drainage to provide a wider perspective of the condition of resident fish communities in the Central Valley of California as a whole. Within the Sacramento drainage, species distributions were correlated with elevational and substrate size gradients; however, the elevation of a sampling site was correlated with a suite of water-quality and habitat variables that are indicative of land use effects on physiochemical stream parameters. Four fish community metrics - percentage of native fish, percentage of intolerant fish, number of tolerant species, and percentage of fish with external anomalies - were responsive to environmental quality. Comparisons between the current study and recent studies in the San Joaquin River drainage suggested that differences in water-management practices may have significant effects on native species fish community structure. Additionally, the results of the current study suggest that index of biotic integrity-type indices can be developed for the Sacramento River Basin and possibly the entire Central Valley, California. The protection of native fish communities in the Central Valley and other arid environments continues to be a conflict between human needs for water resources and the requirements of aquatic ecosystems; preservation of these ecosystems will require innovative management strategies.

  4. Availability of high-magnitude streamflow for groundwater banking in the Central Valley, California

    NASA Astrophysics Data System (ADS)

    Kocis, Tiffany N.; Dahlke, Helen E.

    2017-08-01

    California’s climate is characterized by the largest precipitation and streamflow variability observed within the conterminous US This, combined with chronic groundwater overdraft of 0.6-3.5 km3 yr-1, creates the need to identify additional surface water sources available for groundwater recharge using methods such as agricultural groundwater banking, aquifer storage and recovery, and spreading basins. High-magnitude streamflow, i.e. flow above the 90th percentile, that exceeds environmental flow requirements and current surface water allocations under California water rights, could be a viable source of surface water for groundwater banking. Here, we present a comprehensive analysis of the magnitude, frequency, duration and timing of high-magnitude streamflow (HMF) for 93 stream gauges covering the Sacramento, San Joaquin and Tulare basins in California. The results show that in an average year with HMF approximately 3.2 km3 of high-magnitude flow is exported from the entire Central Valley to the Sacramento-San Joaquin Delta often at times when environmental flow requirements of the Delta and major rivers are exceeded. High-magnitude flow occurs, on average, during 7 and 4.7 out of 10 years in the Sacramento River and the San Joaquin-Tulare Basins, respectively, from just a few storm events (5-7 1-day peak events) lasting for 25-30 days between November and April. The results suggest that there is sufficient unmanaged surface water physically available to mitigate long-term groundwater overdraft in the Central Valley.

  5. Hydro-economic analysis of groundwater pumping for irrigated agriculture in California's Central Valley, USA

    NASA Astrophysics Data System (ADS)

    Medellín-Azuara, Josué; MacEwan, Duncan; Howitt, Richard E.; Koruakos, George; Dogrul, Emin C.; Brush, Charles F.; Kadir, Tariq N.; Harter, Thomas; Melton, Forrest; Lund, Jay R.

    2015-09-01

    As in many places, groundwater in California (USA) is the major alternative water source for agriculture during drought, so groundwater's availability will drive some inevitable changes in the state's water management. Currently, agricultural, environmental, and urban uses compete for groundwater, resulting in substantial overdraft in dry years with lowering of water tables, which in turn increases pumping costs and reduces groundwater pumping capacity. In this study, SWAP (an economic model of agricultural production and water use in California) and C2VISim (the California Department of Water Resources groundwater model for California's Central Valley) are connected. This paper examines the economic costs of pumping replacement groundwater during drought and the potential loss of pumping capacity as groundwater levels drop. A scenario of three additional drought years continuing from 2014 show lower water tables in California's Central Valley and loss of pumping capacity. Places without access to groundwater and with uncertain surface-water deliveries during drought are the most economically vulnerable in terms of crop revenues, employment and household income. This is particularly true for Tulare Lake Basin, which relies heavily on water imported from the Sacramento-San Joaquin Delta. Remote-sensing estimates of idle agricultural land between 2012 and 2014 confirm this finding. Results also point to the potential of a portfolio approach for agriculture, in which crop mixing and conservation practices have substantial roles.

  6. Subsidence in the Central Valley, California 2007 - present measured by InSAR

    NASA Astrophysics Data System (ADS)

    Farr, T. G.; Liu, Z.; Jones, C. E.

    2015-12-01

    Subsidence caused by groundwater pumping in the rich agricultural area of California's Central Valley has been a problem for decades. Over the last few years, interferometric synthetic aperture radar (InSAR) observations from satellite and aircraft platforms have been used to produce maps of subsidence with ~cm accuracy. For this study, we have obtained and analyzed Japanese PALSAR data for 2006 - 2011, Canadian Radarsat-1 data for 2011 - 2013, Radarsat-2 data for 2012 - 2015, and ESA's Sentinel-1A for 2015 and produced maps of subsidence for those periods. High resolution InSAR data were also acquired along the California Aqueduct by the NASA UAVSAR from 2013 - 2015. Using multiple scenes acquired by these systems, we were able to produce the time histories of subsidence at selected locations and transects showing how subsidence varies both spatially and temporally. The maps show that subsidence is continuing in areas with a history of subsidence and that the rates and areas affected have increased due to increased groundwater extraction during the extended western US drought. The high resolution maps from UAVSAR were used to identify and quantify new, highly localized areas of accelerated subsidence along the California Aqueduct that occurred in 2014. The California Department of Water Resources (DWR) funded this work to provide the background and an update on subsidence in the Central Valley to support future policy. Geographic Information System (GIS) files are being furnished to DWR for further analysis of the 4 dimensional subsidence time-series maps. Part of this work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA.

  7. Groundwater withdrawal in the Central Valley, California: implications for San Andreas Fault stressing and lithosphere rheology

    NASA Astrophysics Data System (ADS)

    Lundgren, P.; Liu, Z.; Ali, S. T.; Farr, T.; Faunt, C. C.

    2016-12-01

    Anthropogenic perturbations to crustal loading due to groundwater pumping are increasingly recognized as causing changes in nearby fault stresses. We present preliminary analysis of crustal unloading in the Central Valley (CV), California, for the period 2006-2010 to infer Coulomb stress changes on the central San Andreas Fault (CSAF), lithospheric rheology, and system memory due to more than a century of groundwater withdrawal in the southern CV. We use data-driven unloading estimates to drive three-dimensional (3-D) finite element method models and compare model vertical surface deformation rates with observed GPS uplift rates outside the CV. Groundwater level changes are observed through well water elevation changes and through the resultant surface deformation (subsidence) by interferometric synthetic aperture radar (InSAR) and through broader scale changes in gravity from the GRACE satellite time variable gravity data [Famiglietti et al., 2011] that constrain the overall water volume changes. Combining InSAR with well-water data we are able to estimate the aquifer skeletal elastic and inelastic response and through a linear inversion derive the water volume (load) changes across the Central Valley and compare them with GRACE-inferred groundwater changes. Preliminary 3-D finite element method modeling that considers elastic and viscosity structure in the lithosphere gives three interesting results: 1) elastic models poorly fit the uplift rates near the SAF; 2) viscoelastic models that simulate different unloading histories show the past history of groundwater unloading has significant residual uplift rates and fault stress changes; 3) Coulomb stress change varies from inhibited on the locked (Carrizo) section to promoted on the creeping section of the SAF north of Parkfield. Thus, 3D models that account for lithosphere rheology, loading history viscous relaxation, have significant implications for longer-term time-dependent deformation, stress perturbation, and

  8. Structure and regional significance of the Late Permian(?) Sierra Nevada - Death Valley thrust system, east-central California

    USGS Publications Warehouse

    Stevens, C.H.; Stone, P.

    2005-01-01

    An imbricate system of north-trending, east-directed thrust faults of late Early Permian to middle Early Triassic (most likely Late Permian) age forms a belt in east-central California extending from the Mount Morrison roof pendant in the eastern Sierra Nevada to Death Valley. Six major thrust faults typically with a spacing of 15-20 km, original dips probably of 25-35??, and stratigraphic throws of 2-5 km compose this structural belt, which we call the Sierra Nevada-Death Valley thrust system. These thrusts presumably merge into a de??collement at depth, perhaps at the contact with crystalline basement, the position of which is unknown. We interpret the deformation that produced these thrusts to have been related to the initiation of convergent plate motion along a southeast-trending continental margin segment probably formed by Pennsylvanian transform truncation. This deformation apparently represents a period of tectonic transition to full-scale convergence and arc magmatism along the continental margin beginning in the Late Triassic in central California. ?? 2005 Elsevier B.V. All rights reserved.

  9. Hydrochemistry of the Mahomet Bedrock Valley Aquifer, East-Central Illinois: indicators of recharge and ground-water flow

    USGS Publications Warehouse

    Panno, S.V.; Hackley, Keith C.; Cartwright, K.; Liu, Chao-Li

    1994-01-01

    A conceptual model of the ground-water flow and recharge to the Mahomet Bedrock Valley Aquifer (MVA), east-central Illinois, was developed using major ion chemistry and isotope geochemistry. The MVA is a 'basal' fill in the east-west trending buried bedrock valley composed of clean, permeable sand and gravel to thicknesses of up to 61 m. It is covered by a thick sequence of glacial till containing thinner bodies of interbedded sand and gravel. Ground water from the MVA was found to be characterized by clearly defined geochemical regions with three distinct ground-water types. A fourth ground-water type was found at the confluence of the MVA and the Mackinaw Bedrock Valley Aquifer (MAK) to the west. Ground water in the Onarga Valley, a northeastern tributary of the MVA, is of two types, a mixed cation-SO42- type and a mixed cation-HCO3- type. The ground water is enriched in Na+, Ca2+, Mg2+, and SO42- which appears to be the result of an upward hydraulic gradient and interaction of deeper ground water with oxidized pyritic coals and shale. We suggest that recharge to the Onarga Valley and overlying aquifers is 100% from bedrock (leakage) and lateral flow from the MVA to the south. The central MVA (south of the Onarga Valley) is composed of relatively dilute ground water of a mixed cation-HCO3- type, with low total dissolved solids, and very low concentrations of Cl- and SO42-. Stratigraphic relationships of overlying aquifers and ground-water chemistry of these and the MVA suggest recharge to this region of the MVA (predominantly in Champaign County) is relatively rapid and primarily from the surface. Midway along the westerly flow path of the MVA (western MVA), ground water is a mixed cation-HCO3- type with relatively high Cl-, where Cl- increases abruptly by one to ??? two orders of magnitude. Data suggest that the increase in Cl- is the result of leakage of saline ground water from bedrock into the MVA. Mass-balance calculations indicate that approximately 9.5% of

  10. Spatial use by wintering greater white-fronted geese relative to a decade of habitat change in California's Central Valley

    USGS Publications Warehouse

    Ackerman, Joshua T.; Takekawa, John Y.; Orthmeyer, D.L.; Fleskes, J.P.; Yee, J.L.; Kruse, K.L.

    2006-01-01

    We investigated the effect of recent habitat changes in California's Central Valley on wintering Pacific greater white-fronted geese (Anser albifrons frontalis) by comparing roost-to-feed distances, distributions, population range sizes, and habitat use during 1987-1990 and 1998-2000. These habitat changes included wetland restoration and agricultural land enhancement due to the 1990 implementation of the Central Valley Joint Venture, increased land area used for rice (Oryza sativa) production, and the practice of flooding, rather than burning, rice straw residues for decomposition because of burning restrictions enacted in 1991. Using radiotelemetry, we tracked 192 female geese and recorded 4,516 locations. Geese traveled shorter distances between roosting and feeding sites during 1998-2000 (24.2 ?? 2.2 km) than during 1987-1990 (32.5 ?? 3.4 km); distance traveled tended to decline throughout winter during both decades and varied among watershed basins. Population range size was smaller during 1998-2000 (3,367 km2) than during 1987-1990 (5,145 km2), despite a 2.2-fold increase in the size of the Pacific Flyway population of white-fronted geese during the same time period. The population range size also tended to increase throughout winter during both decades. Feeding and roosting distributions of geese also differed between decades; geese shifted into basins that had the greatest increases in the amount of area in rice production (i.e., American Basin) and out of other basins (i.e., Delta Basin). The use of rice habitat for roosting (1987-1990: 40%, 1998-2000: 54%) and feeding (1987-1990: 57%, 1998-2000: 72%) increased between decades, whereas use of wetlands declined for roosting (1987-1990: 36%, 1998-2000: 31%) and feeding (1987-1990: 22%, 1998-2000: 12%). Within postharvested rice habitats, geese roosted and fed primarily in burned rice fields during 1987-1990 (roost: 43%, feed: 34%), whereas they used flooded rice fields during 1998-2000 (roost: 78%, feed: 64

  11. Remediation of Mudboil Discharges in the Tully Valley of Central New York

    USGS Publications Warehouse

    Kappel, William M.

    2009-01-01

    Mudboils have been documented in the Tully Valley in Onondaga County, in central New York State, since the late 1890s and have continuously discharged sediment-laden (turbid) water into nearby Onondaga Creek since the 1950s. The discharge of sediment causes gradual land-surface subsidence that, in the past, necessitated rerouting a major petroleum pipeline and a buried telephone cable, and caused two road bridges to collapse. The turbid water discharged from mudboils can be either fresh or brackish (salty). Mudboil activity was first reported in the Syracuse, NY, Post Standard in a short article dated October 19, 1899: 'Tully Valley - A Miniature Volcano Few people are aware of the existence of a volcano in this town. It is a small one, to be sure, but very interesting. In the 20-rod gorge where the crossroad leads by the Tully Valley grist mill the hard highway bed has been rising foot after foot till the apex of a cone which has been booming has broken open and quicksand and water flow down the miniature mountain sides. It is an ever increasing cone obliterating wagon tracks as soon as crossed. The nearby bluff is slowly sinking. Probably the highway must sometime be changed on account of the sand and water volcano, unless it ceases its eruption.' This newspaper article accurately describes mudboil activity and presages the collapse of the Otisco Road bridge, 92 years later in 1991. The article indicates that land subsidence occurred nearby, but gives no indication that Onondaga Creek was turbid; this was either an oversight by the reporter or was not a concern at that time.

  12. Coastal, valley, and oasis interaction: impact on the evolution of ancient populations in the South Central Andes.

    PubMed

    Varela, Héctor H; Cocilovo, Jose A; Fuchs, María L; O'Brien, Tyler G

    2014-12-01

    The existing biocultural links are analyzed among ancient inhabitants of the Cochabamba valleys (Bolivia) from the Formative and Tiwanaku periods, coastal and inland Azapa region (Chile) from the Late Archaic to the Late periods, and the Atacama Desert oases (Chile) from the Formative period to the time of European contact. Craniometric information obtained from a sample of 565 individuals from different sites of the studied regions was evaluated using methods derived from quantitative genetics and multivariate statistical analysis techniques. It is shown that during the Formative and Tiwanaku periods inhabitants of the Cochabamba valleys maintained contact with the population of northern Chile. This contact was more fluid with the people from the interior valley of Azapa than it was with the settlers of San Pedro Atacama (SPA). An important biological affinity in the Late Period between the inhabitants of the Azapa valley and the late SPA groups is also examined. The Late-Inca Catarpe SPA sample shows a broad genetic variability shared with the majority of the groups studied. The results reaffirm the differences between the coastal and interior Azapa valley groups and strengthen the hypothesis of two pathways to populating the south central Andean area. The divergence observed among subpopulations can be explained by the spatiotemporal dispersion between them, genetic drift dispersion compensated by the action of gene flow, and cultural norms that regulate within group mating. © 2014 Wiley Periodicals, Inc.

  13. [Ethnic conflicts and environmental degradation in Central Asia. The Ferghana valley and northern Kazakhstan].

    PubMed

    De Cordier, B

    1996-01-01

    This work seeks to demonstrate that the combination of ecological degradation, demographic pressure, and ethnic heterogeneity in Central Asia constitute a serious threat to the future stability of the region. The predominantly rural Ferghana Valley and Northern Kazakhstan suffer from shortages of water and land and from unemployment that leads to extensive out-migration to cities suffering from decline in their Soviet-era industries. The problem in the Ferghana Valley began with Tsarist conquest of the valley in 1876 and the subsequent imposition of cotton cultivation, which was greatly expanded by the Soviet Union. The Ferghana Valley, despite being a natural unit, was divided between Uzbekistan, Tajikistan, and Kyrgyzstan in the 1920s and 1930s, and remains divided between the independent states. The current population of 11 million is ethnically diverse, with Uzbeks in the majority and increasing most rapidly. Immigration from the Caucasus since 1950 added to the tension. Future peace will depend on such factors as whether the neo-Communist political regime chooses to incite ethnic hostilities, the manner in which land is redistributed, and the outcome of struggles for control of the flourishing narcotics trade. The northern Kazakhstan region was designated a pioneer wheat-growing region by Soviet planners in 1954. Russian and Ukrainian migrants established between 1954 and 1956 are today the predominant population sector, but feel their privileged position threatened by nationalist policies making Kazakh the official language and giving preference in employment to Kazakhs. Resettlement of Kazakhs from Mongolia, China, and Afghanistan in the region and the high Kazakh birth rate increase tensions. Grain production initially grew rapidly, but the mediocre soil and erosion-inducing constant dry winds have caused production to stagnate or decline. Regional disputes within Kazakhstan complicate the situation. Northern Kazakhstan, with its industrial development, is

  14. An Investigation into the Involvement of California Central Valley High School Students with Disabilities in the IEP Process

    ERIC Educational Resources Information Center

    Anderson, Cheryle Ann

    2012-01-01

    The purpose of this study was to investigate the involvement of California Central Valley high school students with disabilities in the Individual Education Plan (IEP) process. Specifically, this study investigated the involvement of students with disabilities in the development of the IEP and IEP meetings. In addition, this study explored the…

  15. Quaternary landscape evolution of tectonically active intermontane basins: the case of the Middle Aterno River Valley (Abruzzo, Central Italy)

    NASA Astrophysics Data System (ADS)

    Falcucci, Emanuela; Gori, Stefano; Della Seta, Marta; Fubelli, Giandomenico; Fredi, Paola

    2014-05-01

    The Middle Aterno River Valley is characterised by different Quaternary tectonic depressions localised along the present course of the Aterno River (Central Apennine) .This valley includes the L'Aquila and Paganica-Castelnuovo-San Demetrio tectonic basins, to the North, the Middle Aterno Valley and the Subequana tectonic basin, to the South. The aim of this contribution is to improve the knowledge about the Quaternary geomorphological and tectonic evolution of this portion of the Apennine chain. A synchronous lacustrine depositional phase is recognized in all these basins and attributed to the Early Pleistocene by Falcucci et al. (2012). At that time, this sector of the chain showed four distinct closed basins, hydrologically separated from each other and from the Sulmona depression. This depression, actually a tectonic basin too, was localized South of the Middle Aterno River Valley and it was drained by an endorheic hydrographic network. The formation of these basins was due to the activity of different fault systems, namely the Upper Aterno River Valley-Paganica system and San Pio delle Camere fault, to the North, and the Middle Aterno River Valley-Subequana Valley fault system to the South. These tectonic structures were responsible for the origin of local depocentres inside the depressions which hosted the lacustrine basins. Ongoing surveys in the uppermost sectors of the Middle Aterno River Valley revealed the presence of sub-horizontal erosional surfaces that are carved onto the carbonate bedrock and suspended several hundreds of metres over the present thalweg. Gently dipping slope breccias referred to the Early Pleistocene rest on these surfaces, thus suggesting the presence of an ancient low-gradient landscape adjusting to the local base level.. Subsequently, this ancient low relief landscape underwent a strong erosional phase during the Middle Pleistocene. This erosional phase is testified by the occurrence of valley entrenchment and of coeval fluvial

  16. The Effects of Mountaintop Mines and Valley Fills on Aquatic Ecosystems of the Central Appalachian Coalfields (External Review Draft)

    EPA Science Inventory

    This report assesses the state of the science on the environmental impacts of mountaintop mines and valley fills (MTM-VF) on streams in the Central Appalachian Coalfields. Our review focused on the aquatic impacts of mountaintop removal coal mining, which, as its name suggests, ...

  17. Reconstruction of Flooding Events for the Central Valley, California from Instrumental and Documentary Weather Records

    NASA Astrophysics Data System (ADS)

    Dodds, S. F.; Mock, C. J.

    2009-12-01

    All available instrumental winter precipitation data for the Central Valley of California back to 1850 were digitized and analyzed to construct continuous time series. Many of these data, in paper or microfilm format, extend prior to modern National Weather Service Cooperative Data Program and Historical Climate Network data, and were recorded by volunteer observers from networks such as the US Army Surgeon General, Smithsonian Institution, and US Army Signal Service. Given incomplete individual records temporally, detailed documentary data from newspapers, personal diaries and journals, ship logbooks, and weather enthusiasts’ instrumental data, were used in conjunction with instrumental data to reconstruct precipitation frequency per month and season, continuous days of precipitation, and to identify anomalous precipitation events. Multilinear regression techniques, using surrounding stations and the relationships between modern and historical records, bridge timeframes lacking data and provided homogeneous nature of time series. The metadata for each station was carefully screened, and notes were made about any possible changes to the instrumentation, location of instruments, or an untrained observer to verify that anomalous events were not recorded incorrectly. Precipitation in the Central Valley varies throughout the entire region, but waterways link the differing elevations and latitudes. This study integrates the individual station data with additional accounts of flood descriptions through unique newspaper and journal data. River heights and flood extent inundating cities, agricultural lands, and individual homes are often recorded within unique documentary sources, which add to the understanding of flood occurrence within this area. Comparisons were also made between dam and levee construction through time and how waters are diverted through cities in natural and anthropogenically changed environments. Some precipitation that lead to flooding events that

  18. Spatiotemporal Patterns of Ice Mass Variations and the Local Climatic Factors in the Riparian Zone of Central Valley, California

    NASA Astrophysics Data System (ADS)

    Inamdar, P.; Ambinakudige, S.

    2016-12-01

    Californian icefields are natural basins of fresh water. They provide irrigation water to the farms in the central valley. We analyzed the ice mass loss rates, air temperature and land surface temperature (LST) in Sacramento and San Joaquin basins in California. The digital elevation models from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) were used to calculate ice mass loss rate between the years 2002 and 2015. Additionally, Landsat TIR data were used to extract the land surface temperature. Data from local weather stations were analyzed to understand the spatiotemporal trends in air temperature. The results showed an overall mass recession of -0.8 ± 0.7 m w.e.a-1. We also noticed an about 60% loss in areal extent of the glaciers in the study basins between 2000 and 2015. Local climatic factors, along with the global climate patterns might have influenced the negative trends in the ice mass loss. Overall, there was an increase in the air temperature by 0.07± 0.02 °C in the central valley between 2000 and 2015. Furthermore, LST increased by 0.34 ± 0.4 °C and 0.55± 0.1 °C in the Sacramento and San Joaquin basins. Our preliminary results show the decrease in area and mass of ice mass in the basins, and changing agricultural practices in the valley.

  19. Assessing Drought Impacts on Water Storage using GRACE Satellites and Regional Groundwater Modeling in the Central Valley of California

    NASA Astrophysics Data System (ADS)

    Scanlon, B. R.; Zhang, Z.; Save, H.; Faunt, C. C.; Dettinger, M. D.

    2015-12-01

    Increasing concerns about drought impacts on water resources in California underscores the need to better understand effects of drought on water storage and coping strategies. Here we use a new GRACE mascons solution with high spatial resolution (1 degree) developed at the Univ. of Texas Center for Space Research (CSR) and output from the most recent regional groundwater model developed by the U.S. Geological Survey to evaluate changes in water storage in response to recent droughts. We also extend the analysis of drought impacts on water storage back to the 1980s using modeling and monitoring data. The drought has been intensifying since 2012 with almost 50% of the state and 100% of the Central Valley under exceptional drought in 2015. Total water storage from GRACE data declined sharply during the current drought, similar to the rate of depletion during the previous drought in 2007 - 2009. However, only 45% average recovery between the two droughts results in a much greater cumulative impact of both droughts. The CSR GRACE Mascons data offer unprecedented spatial resolution with no leakage to the oceans and no requirement for signal restoration. Snow and reservoir storage declines contribute to the total water storage depletion estimated by GRACE with the residuals attributed to groundwater storage. Rates of groundwater storage depletion are consistent with the results of regional groundwater modeling in the Central Valley. Traditional approaches to coping with these climate extremes has focused on surface water reservoir storage; however, increasing conjunctive use of surface water and groundwater and storing excess water from wet periods in depleted aquifers is increasing in the Central Valley.

  20. New observations of VOC emissions and concentrations in, above, and around the Central Valley of California

    NASA Astrophysics Data System (ADS)

    Goldstein, A. H.; Fares, S.; Gentner, D. R.; Park, J.; Weber, R.; Ormeno, E.; Holzinger, R.; Misztal, P. K.; Karl, T. R.; Guenther, A. B.; Fischer, M. L.; Harley, R. A.; Karlik, J. F.

    2011-12-01

    Large portions of the Central Valley of California are out of compliance with current state and federal air quality standards for ozone and particulate matter, and the relative importance of biogenic and anthropogenic VOC emissions to their photochemical production in this region remains uncertain. In 2009-2011 multiple measurement campaigns were completed investigating the VOC emission inventory and concentration distributions. In 2009 BVOC emissions from more than 20 species of major agricultural crops in California were measured in a greenhouse using branch enclosures by both PTRMS and in-situ GC. Overall, crops were found to emit low amounts of BVOC compared to the natural forests surrounding the valley. Crops mainly emitted methanol and terpenes, with a broad array of other species emitted at lower levels, and all the measured crops showed negligible emissions of isoprene. Navel oranges were the largest crop BVOC emitters measured so a full year of flux measurements were made in an orange grove near Visalia in 2010 by eddy covariance(EC)-PTRMS with two multi-week periods of concentration measurements by hourly in-situ GC, and one month of high mass resolution flux measurements by EC-PTR-TOF-MS. The dominant BVOC emissions from the orange grove were methanol and terpenes, followed by acetone, acetaldehyde, and a low level of emissions for many other species. In 2011 aircraft eddy covariance measurements of BVOC fluxes were made by EC-PTRMS covering a large area of California as part of the California Airborne Bvoc Emission Research in Natural Ecosystem Transects (CABERNET) campaign aimed at improving BVOC emission models on regional scales, mainly profiling BVOC emissions from oak woodlands surrounding the Central Valley. In 2010, hourly in-situ VOC measurements were made via in-situ GC in Bakersfield, CA as part of the CalNex experiment. Additionally, in-situ measurements of fresh motor vehicle exhaust were made in Oakland's Caldecott tunnel. Measurements by

  1. Combined cGPS and InSAR time series for observing subsidence in the southern Central Valley due to groundwater exploitation

    NASA Astrophysics Data System (ADS)

    Neely, W.; Borsa, A. A.; Silverii, F.

    2017-12-01

    Recent droughts have increased reliance on groundwater for agricultural production in California's Central Valley. Using Interferometric Synthetic Aperture Radar (InSAR), we observe upwards of 25 cm/yr of subsidence from November 2014 to February 2017 due to intense pumping. However, these observations are contaminated by atmospheric noise and orbital errors. We present a novel method for correcting long wavelength errors in InSAR deformation estimates using time series from continuous Global Positioning System (cGPS) stations within the SAR footprint, which we apply to C-band data from the Sentinel mission. We test our method using 49 SAR acquisitions from the Sentinel 1 satellites and 107 cGPS times series from the Geodesy Advancing Geoscience and EarthScope (GAGE) network in southern Central Valley. We correct each interferogram separately, implementing an intermittent Small Baseline Subset (ISBAS) technique to produce a time series of line-of-sight surface motion from 276 InSAR pairs. To estimate the vertical component of this motion, we remove horizontal tectonic displacements predicted by the Southern California Earthquake Center's (SCEC) Community Geodetic Model. We validate our method by comparing the corrected InSAR results with independent cGPS data and find a marked improvement in agreement between the two data sets, particularly in the deformation rates. Using this technique, we characterize the time evolution of surface vertical deformation in the southern Central Valley related to human exploitation of local groundwater resources. This methodology is applicable to data from other SAR satellites, including ALOS-2 and the upcoming US-India NISAR mission.

  2. Effectiveness and Tradeoffs between Portfolios of Adaptation Strategies Addressing Future Climate and Socioeconomic Uncertainties in California's Central Valley

    NASA Astrophysics Data System (ADS)

    Tansey, M. K.; Van Lienden, B.; Das, T.; Munevar, A.; Young, C. A.; Flores-Lopez, F.; Huntington, J. L.

    2013-12-01

    The Central Valley of California is one of the major agricultural areas in the United States. The Central Valley Project (CVP) is operated by the Bureau of Reclamation to serve multiple purposes including generating approximately 4.3 million gigawatt hours of hydropower and providing, on average, 5 million acre-feet of water per year to irrigate approximately 3 million acres of land in the Sacramento, San Joaquin, and Tulare Lake basins, 600,000 acre-feet per year of water for urban users, and 800,000 acre-feet of annual supplies for environmental purposes. The development of effective adaptation and mitigation strategies requires assessing multiple risks including potential climate changes as well as uncertainties in future socioeconomic conditions. In this study, a scenario-based analytical approach was employed by combining three potential 21st century socioeconomic futures with six representative climate and sea level change projections developed using a transient hybrid delta ensemble method from an archive of 112 bias corrected spatially downscaled CMIP3 global climate model simulations to form 18 future socioeconomic-climate scenarios. To better simulate the effects of climate changes on agricultural water demands, analyses of historical agricultural meteorological station records were employed to develop estimates of future changes in solar radiation and atmospheric humidity from the GCM simulated temperature and precipitation. Projected changes in atmospheric carbon dioxide were computed directly by weighting SRES emissions scenarios included in each representative climate projection. These results were used as inputs to a calibrated crop water use, growth and yield model to simulate the effects of climate changes on the evapotranspiration and yields of major crops grown in the Central Valley. Existing hydrologic, reservoir operations, water quality, hydropower, greenhouse gas (GHG) emissions and both urban and agricultural economic models were integrated

  3. High Resolution Airborne InSAR DEM of Bagley Ice Valley, South-central Alaska: Geodetic Validation with Airborne Laser Altimeter Data

    NASA Astrophysics Data System (ADS)

    Muskett, R. R.; Lingle, C. S.; Echelmeyer, K. A.; Valentine, V. B.; Elsberg, D.

    2001-12-01

    Bagley Ice Valley, in the St. Elias and Chugach Mountains of south-central Alaska, is an integral part of the largest connected glacierized terrain on the North American continent. From the flow divide between Mt. Logan and Mt. St. Elias, Bagley Ice Valley flows west-northwest for some 90 km down a slope of less than 1o, at widths up to 15 km, to a saddle-gap where it turns south-west to become Bering Glacier. During 4-13 September 2000, an airborne survey of Bagley Ice Valley was performed by Intermap Technologies, Inc., using their Star-3i X-band SAR interferometer. The resulting digital elevation model (DEM) covers an area of 3243 km2. The DEM elevations are orthometric heights, in meters above the EGM96 geoid. The horizontal locations of the 10-m postings are with respect to the WGS84 ellipsoid. On 26 August 2000, 9 to 18 days prior to the Intermap Star-3i survey, a small-aircraft laser altimeter profile was acquired along the central flow line for validation. The laser altimeter data consists of elevations above the WGS84 ellipsoid and orthometric heights above GEOID99-Alaska. Assessment of the accuracy of the Intermap Star-3i DEM was made by comparison of both the DEM orthometric heights and elevations above the WGS84 ellipsoid with the laser altimeter data. Comparison of the orthometric heights showed an average difference of 5.4 +/- 1.0 m (DEM surface higher). Comparison of elevations above the WGS84 ellipsoid showed an average difference of -0.77 +/- 0.93 m (DEM surface lower). This indicates that the X-band Star-3i interferometer was penetrating the glacier surface by an expected small amount. The WGS84 comparison is well within the 3 m RMS accuracy quoted for GT-3 DEM products. Snow accumulation may have occurred, however, on Bagley Ice Valley between 26 August and 4-13 September 2000. This will be estimated using a mass balance model and used to correct the altimeter-derived surface heights. The new DEM of Bagley Ice Valley will provide a reference

  4. A plan to study the aquifer system of the Central Valley of California

    USGS Publications Warehouse

    Bertoldi, Gilbert L.

    1979-01-01

    Unconsolidated Quaternary alluvial deposits comprise a large complex aquifer system in the Central Valley of California. Millions of acre-feet of water is pumped from the system annually to support a large and expanding agribusiness industry. Since the 1950's, water levels have been steadily declining in many areas of the valley and concern has been expressed about the ability of the entire ground-water system to support agribusiness at current levels, not to mention its ability to function at projected expansion levels. At current levels of ground-water use, an estimated 1.5 to 2 million acre-feet is withdrawn from storage each year; that is, 1.5 to 2 million acre-feet of water is pumped annually in excess of annual replenishment. The U.S. Geological Survey has initiated a 4-year study to develop geologic, hydrologic, and hydraulic information and to establish a valleywide ground-water data base that will be used to build computer models of the ground-water flow system. Subsequently, these models may be used to evaluate the system response to various ground-water management alternatives. This report describes current problems, objectives of the study, and outlines the general work to be accomplished in the study area. A bibliography of about 600 references is included. (Kosco-USGS)

  5. Principal facts for gravity stations in the Dry Valley area, west-central Nevada and east-central California

    USGS Publications Warehouse

    Sanger, Elizabeth A.; Ponce, David A.

    2003-01-01

    In June, 2002, the U.S. Geological Survey (USGS) established 143 new gravity stations and 12 new rock samples in the Dry Valley area, 30 miles north of Reno, Nevada, on the California - Nevada border (see fig. 1). This study reports on gravity, magnetic, and physical property data intended for use in modeling the geometry and depth of Dry Valley for groundwater analysis. It is part of a larger study that aims to characterize the hydrologic framework of several basins in Washoe County. Dry Valley is located south of the Fort Sage Mountains and south-east of Long Valley, on USGS 7.5’ quadrangles Constantia and Seven Lakes (fig. 2). The Cretaceous granitic rocks and Tertiary volcanic rocks that bound the sediment filled basin (fig. 3) may be especially important to future modeling because of their impact on groundwater flow. The granitic and volcanic rocks of Dry Valley exhibit densities and magnetic susceptibilities higher than the overlaying sediments, and create a distinguishable pattern of gravity and magnetic anomalies that reflect these properties.

  6. In Search of Equity and Excellence for Central Valley Education: Teacher Educator Perceptions of Preparing Multiple Subject Preservice Teachers

    ERIC Educational Resources Information Center

    Handy, Jennifer Lima-Costa

    2017-01-01

    There is growing concern that the California school system is failing to ensure equity and excellence for all students. This research sought to understand the perceptions of teacher educators at a California public university in the Central Valley with regards to what they believe multiple-subject preservice teachers need to know, be able to do,…

  7. Death Valley California as seen from STS-59

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This oblique handheld Hasselblad 70mm photo shows Death Valley, near California's border with Nevada. The valley -- the central feature of Death Valley National Monument -- extends north to south for some 140 miles (225 kilometers). Hemmed in to the east by the Amargosa Range and to the west by the Panamints, its width varies from 5 to 15 miles (8 to 24 kilometers).

  8. Groundwater Quality in the Central Eastside San Joaquin Valley, California

    USGS Publications Warehouse

    Belitz, Kenneth; Landon, Matthew K.

    2010-01-01

    The Central Eastside study unit is located in California's San Joaquin Valley. The 1,695 square mile study unit includes three groundwater subbasins: Modesto, Turlock, and Merced (California Department of Water Resources, 2003). The primary water-bearing units consist of discontinuous lenses of gravel, sand, silt, and clay, which are derived largely from the Sierra Nevada Mountains to the east. Public-supply wells provide most of the drinking water supply in the Central Eastside. Consequently, the primary aquifer in the Central Eastside study unit is defined as that part of the aquifer corresponding to the perforated interval of wells listed in the California Department of Public Health database. Public-supply wells are typically drilled to depths of 200 to 350 feet, consist of solid casing from the land surface to a depth of about 100 to 200 feet, and they are perforated below the solid casing. Water quality in the shallower and deeper parts of the aquifer system may differ from that in the primary aquifer. The Central Eastside study unit has hot and dry summers and cool, moist, winters. Average annual rainfall ranges from 11 to 15 inches. The Stanislaus, Tuolumne, and Merced Rivers, with headwaters in the Sierra Nevada Mountains, are the primary streams traversing the study unit. Land use in the study unit is approximately 59 percent (%) agricultural, 34% natural (primarily grassland), and 7% urban. The primary crops are almonds, walnuts, peaches, grapes, grain, corn, and alfalfa. The largest urban areas (2003 population in parentheses) are the cities of Modesto (206,872), Turlock (63,467), and Merced (69,512). Municipal water use accounts for about 5% of the total water use in the Central Eastside study unit, with the remainder used for irrigated agriculture. Groundwater accounts for about 75% of the municipal supply, and surface water accounts for about 25%. Recharge to the groundwater flow system is primarily from percolation of irrigation return

  9. Tomographic Rayleigh-wave group velocities in the Central Valley, California centered on the Sacramento/San Joaquin Delta

    USGS Publications Warehouse

    Fletcher, Jon Peter B.; Erdem, Jemile; Seats, Kevin; Lawrence, Jesse

    2016-01-01

    If shaking from a local or regional earthquake in the San Francisco Bay region were to rupture levees in the Sacramento/San Joaquin Delta then brackish water from San Francisco Bay would contaminate the water in the Delta: the source of fresh water for about half of California. As a prelude to a full shear-wave velocity model that can be used in computer simulations and further seismic hazard analysis, we report on the use of ambient noise tomography to build a fundamental-mode, Rayleigh-wave group velocity model for the region around the Sacramento/San Joaquin Delta in the western Central Valley, California. Recordings from the vertical component of about 31 stations were processed to compute the spatial distribution of Rayleigh wave group velocities. Complex coherency between pairs of stations were stacked over 8 months to more than a year. Dispersion curves were determined from 4 to about 18 seconds. We calculated average group velocities for each period and inverted for deviations from the average for a matrix of cells that covered the study area. Smoothing using the first difference is applied. Cells of the model were about 5.6 km in either dimension. Checkerboard tests of resolution, which is dependent on station density, suggest that the resolving ability of the array is reasonably good within the middle of the array with resolution between 0.2 and 0.4 degrees. Overall, low velocities in the middle of each image reflect the deeper sedimentary syncline in the Central Valley. In detail, the model shows several centers of low velocity that may be associated with gross geologic features such as faulting along the western margin of the Central Valley, oil and gas reservoirs, and large cross cutting features like the Stockton arch. At shorter periods around 5.5s, the model’s western boundary between low and high velocities closely follows regional fault geometry and the edge of a residual isostatic gravity low. In the eastern part of the valley, the boundaries

  10. Tomographic Rayleigh wave group velocities in the Central Valley, California, centered on the Sacramento/San Joaquin Delta

    NASA Astrophysics Data System (ADS)

    Fletcher, Jon B.; Erdem, Jemile; Seats, Kevin; Lawrence, Jesse

    2016-04-01

    If shaking from a local or regional earthquake in the San Francisco Bay region were to rupture levees in the Sacramento/San Joaquin Delta, then brackish water from San Francisco Bay would contaminate the water in the Delta: the source of freshwater for about half of California. As a prelude to a full shear-wave velocity model that can be used in computer simulations and further seismic hazard analysis, we report on the use of ambient noise tomography to build a fundamental mode, Rayleigh wave group velocity model for the region around the Sacramento/San Joaquin Delta in the western Central Valley, California. Recordings from the vertical component of about 31 stations were processed to compute the spatial distribution of Rayleigh wave group velocities. Complex coherency between pairs of stations was stacked over 8 months to more than a year. Dispersion curves were determined from 4 to about 18 s. We calculated average group velocities for each period and inverted for deviations from the average for a matrix of cells that covered the study area. Smoothing using the first difference is applied. Cells of the model were about 5.6 km in either dimension. Checkerboard tests of resolution, which are dependent on station density, suggest that the resolving ability of the array is reasonably good within the middle of the array with resolution between 0.2 and 0.4°. Overall, low velocities in the middle of each image reflect the deeper sedimentary syncline in the Central Valley. In detail, the model shows several centers of low velocity that may be associated with gross geologic features such as faulting along the western margin of the Central Valley, oil and gas reservoirs, and large crosscutting features like the Stockton arch. At shorter periods around 5.5 s, the model's western boundary between low and high velocities closely follows regional fault geometry and the edge of a residual isostatic gravity low. In the eastern part of the valley, the boundaries of the low

  11. Searching for evidence of changes in extreme rainfall indices in the Central Rift Valley of Ethiopia

    NASA Astrophysics Data System (ADS)

    Muluneh, Alemayehu; Bewket, Woldeamlak; Keesstra, Saskia; Stroosnijder, Leo

    2017-05-01

    Extreme rainfall events have serious implications for economic sectors with a close link to climate such as agriculture and food security. This holds true in the Central Rift Valley (CRV) of Ethiopia where communities rely on highly climate-sensitive rainfed subsistence farming for livelihoods. This study investigates changes in ten extreme rainfall indices over a period of 40 years (1970-2009) using 14 meteorological stations located in the CRV. The CRV consists of three landscape units: the valley floor, the escarpments, and the highlands all of which are considered in our data analysis. The Belg (March-May) and Kiremt (June-September) seasons are also considered in the analysis. The Mann-Kendall test was used to detect trends of the rainfall indices. The results indicated that at the annual time scale, more than half (57 %) of the stations showed significant trends in total wet-day precipitation (PRCPTOT) and heavy precipitation days (R10mm). Only 7-35 % of stations showed significant trends, for the other rainfall indices. Spatially, the valley floor received increasing annual rainfall while the escarpments and the highlands received decreasing annual rainfall over the last 40 years. During Belg, 50 % of the stations showed significant increases in the maximum number of consecutive dry days (CDD) in all parts of the CRV. However, most other rainfall indices during Belg showed no significant changes. During Kiremt, considering both significant and non-significant trends, almost all rainfall indices showed an increasing trend in the valley floor and a decreasing trend in the escarpment and highlands. During Belg and Kiremt, the CDD generally showed increasing tendency in the CRV.

  12. 10Be exposure age chronology of the last glaciation of the Roháčská Valley in the Western Tatra Mountains, central Europe

    NASA Astrophysics Data System (ADS)

    Engel, Zbyněk; Mentlík, Pavel; Braucher, Régis; Křížek, Marek; Pluháčková, Markéta; Arnold, Maurice; Aumaître, Georges; Bourlès, Didier; Keddadouche, Karim; Aster Team; Arnold, Maurice; Aumaître, Georges; Bourlès, Didier; Keddadouche, Karim

    2017-09-01

    10Be exposure ages from moraines and bedrock sites in the Roháčská Valley provide chronology of the last glaciation in the largest valley of the Western Tatra Mts., the Western Carpathians. The minimum apparent exposure age of 19.4 ± 2.1 ka obtained for the oldest sampled boulder and the mean age of 18.0 ± 0.8 ka calculated for the terminal moraine indicate that the oldest preserved moraine was probably deposited at the time of the global Last Glacial Maximum (LGM). The age of this moraine coincides with the termination of the maximum glacier expansion in other central European ranges, including the adjacent High Tatra Mts. and the Alps. The equilibrium line altitude (ELA) of the LGM glacier in the Roháčská Valley, estimated at 1400-1410 m a.s.l., was 50-80 m lower than in the eastern part of the range, indicating a positive ELA gradient from west to east among the north-facing glaciers in the Tatra Mts. Lateglacial glacier expansion occurred no later than 13.4 ± 0.5 ka and 11.9 ± 0.5 ka, as indicated by the mean exposure ages calculated for re-advance moraines. This timing is consistent with the exposure age chronology of the last Lateglacial re-advance in the High Tatra Mts., Alps and lower mountain ranges in central Europe. The ELA in the Roháčská Valley estimated at 1690-1770 m a.s.l. in this period was located 130-300 m lower than in the north-facing valleys in the High Tatra Mts. 10Be exposure ages obtained for a rock glacier constrains the timing of this landform stabilization in the Salatínska Valley and provides the first chronological evidence for the Lateglacial activity of rock glaciers in the Carpathians.

  13. Emission rates of organics from vegetation in California's Central Valley

    NASA Astrophysics Data System (ADS)

    Winer, Arthur M.; Arey, Janet; Atkinson, Roger; Aschmann, Sara M.; Long, William D.; Morrison, C. Lynn; Olszyk, David M.

    Rates of emission of speciated hydrocarbons have been determined for more than 30 of the most dominant (based on acreage) agricultural and natural plant types found in California's Central Valley. These measurements employed flow-through Teflon chambers, sample collection on solid adsorbent and thermal desorption gas chromatography (GC) and GC-mass spectrometry analysis to identify more than 40 individual organic compounds. In addition to isoprene and the monoterpenes, we observed sesquiterpenes, alcohols, acetates, aldehydes, ketones, ethers, esters, alkanes, alkenes and aromatics as emissions from these plant species. Mean emission rates for total monoterpenes ranged from none detected in the case of beans, grapes, rice and wheat, to as high as 12-30 μg h -1 g -1 for pistachio and tomato (normalized to dry leaf and total biomass, respectively). Other agricultural species exhibiting substantial rates of emission of monoterpenes included carrot, cotton, lemon, orange and walnut. All of the plant species studied showed total assigned compound emission rates in the range between 0.1 and 36 νg h -1 g -1.

  14. California's restless giant: the Long Valley Caldera

    USGS Publications Warehouse

    Hill, David P.; Bailey, Roy A.; Hendley, James W.; Stauffer, Peter H.; Marcaida, Mae

    2014-01-01

    Scientists have monitored geologic unrest in the Long Valley, California, area since 1980. In that year, following a swarm of strong earthquakes, they discovered that the central part of the Long Valley Caldera had begun actively rising. Unrest in the area persists today. The U.S. Geological Survey (USGS) continues to provide the public and civil authorities with current information on the volcanic hazard at Long Valley and is prepared to give timely warnings of any impending eruption.

  15. Prediction and visualization of redox conditions in the groundwater of Central Valley, California

    USGS Publications Warehouse

    Rosecrans, Celia Z.; Nolan, Bernard T.; Gronberg, JoAnn M.

    2017-01-01

    Regional-scale, three-dimensional continuous probability models, were constructed for aspects of redox conditions in the groundwater system of the Central Valley, California. These models yield grids depicting the probability that groundwater in a particular location will have dissolved oxygen (DO) concentrations less than selected threshold values representing anoxic groundwater conditions, or will have dissolved manganese (Mn) concentrations greater than selected threshold values representing secondary drinking water-quality contaminant levels (SMCL) and health-based screening levels (HBSL). The probability models were constrained by the alluvial boundary of the Central Valley to a depth of approximately 300 m. Probability distribution grids can be extracted from the 3-D models at any desired depth, and are of interest to water-resource managers, water-quality researchers, and groundwater modelers concerned with the occurrence of natural and anthropogenic contaminants related to anoxic conditions.Models were constructed using a Boosted Regression Trees (BRT) machine learning technique that produces many trees as part of an additive model and has the ability to handle many variables, automatically incorporate interactions, and is resistant to collinearity. Machine learning methods for statistical prediction are becoming increasing popular in that they do not require assumptions associated with traditional hypothesis testing. Models were constructed using measured dissolved oxygen and manganese concentrations sampled from 2767 wells within the alluvial boundary of the Central Valley, and over 60 explanatory variables representing regional-scale soil properties, soil chemistry, land use, aquifer textures, and aquifer hydrologic properties. Models were trained on a USGS dataset of 932 wells, and evaluated on an independent hold-out dataset of 1835 wells from the California Division of Drinking Water. We used cross-validation to assess the predictive performance of

  16. Prediction and visualization of redox conditions in the groundwater of Central Valley, California

    NASA Astrophysics Data System (ADS)

    Rosecrans, Celia Z.; Nolan, Bernard T.; Gronberg, JoAnn M.

    2017-03-01

    Regional-scale, three-dimensional continuous probability models, were constructed for aspects of redox conditions in the groundwater system of the Central Valley, California. These models yield grids depicting the probability that groundwater in a particular location will have dissolved oxygen (DO) concentrations less than selected threshold values representing anoxic groundwater conditions, or will have dissolved manganese (Mn) concentrations greater than selected threshold values representing secondary drinking water-quality contaminant levels (SMCL) and health-based screening levels (HBSL). The probability models were constrained by the alluvial boundary of the Central Valley to a depth of approximately 300 m. Probability distribution grids can be extracted from the 3-D models at any desired depth, and are of interest to water-resource managers, water-quality researchers, and groundwater modelers concerned with the occurrence of natural and anthropogenic contaminants related to anoxic conditions. Models were constructed using a Boosted Regression Trees (BRT) machine learning technique that produces many trees as part of an additive model and has the ability to handle many variables, automatically incorporate interactions, and is resistant to collinearity. Machine learning methods for statistical prediction are becoming increasing popular in that they do not require assumptions associated with traditional hypothesis testing. Models were constructed using measured dissolved oxygen and manganese concentrations sampled from 2767 wells within the alluvial boundary of the Central Valley, and over 60 explanatory variables representing regional-scale soil properties, soil chemistry, land use, aquifer textures, and aquifer hydrologic properties. Models were trained on a USGS dataset of 932 wells, and evaluated on an independent hold-out dataset of 1835 wells from the California Division of Drinking Water. We used cross-validation to assess the predictive performance of

  17. Integrated simulation of consumptive use and land subsidence in the Central Valley, California, for the past and for a future subject to urbanization and climate change

    USGS Publications Warehouse

    Hanson, Randall T.; Flint, Alan L.; Faunt, Claudia C.; Cayan, Daniel R.; Flint, Lorraine E.; Leake, Stanley A.; Schmid, Wolfgang

    2010-01-01

    Competition for water resources is growing throughout California, particularly in the Central Valley where about 20% of all groundwater used in the United States is consumed for agriculture and urban water supply. Continued agricultural use coupled with urban growth and potential climate change would result in continued depletion of groundwater storage and associated land subsidence throughout the Central Valley. For 1962-2003, an estimated 1,230 hectare meters (hm3) of water was withdrawn from fine-grained beds, resulting in more than three meters (m) of additional land subsidence locally. Linked physically-based, supply-constrained and emanddriven hydrologic models were used to simulate future hydrologic conditions under the A2 climate projection scenario that assumes continued "business as usual" greenhouse gas emissions. Results indicate an increased subsidence in the second half of the twenty-first century. Potential simulated land subsidence extends into urban areas and the eastern side of the valley where future surface-water deliveries may be depleted. 

  18. Paleoseismology of a possible fault scarp in Wenas Valley, central Washington

    USGS Publications Warehouse

    Sherrod, Brian L.; Barnett, Elizabeth A.; Knepprath, Nichole; Foit, Franklin F.

    2013-01-01

    In October 2009, two trenches excavated across an 11-kilometer-long scarp at Wenas Valley in central Washington exposed evidence for late Quaternary deformation. Lidar imagery of the Wenas Valley illuminated the west-northwest-trending, 2- to 8-meter-high scarp as it bisected alluvial fans developed at the mouths of canyons along the south side of Umtanum Ridge. The alignment of the scarp and aeromagnetic lineaments suggested that the scarp may be a product of and controlled by the same tectonic structure that produced the magnetic lineaments. Several large landslides mapped in the area demonstrated the potential for large mass-wasting events in the area. In order to test whether the scarp was the result of an earthquake-generated surface rupture or a landslide, trenches were excavated at Hessler Flats and McCabe Place. The profiles of bedrock and soil stratigraphy that underlie the scarp in each trench were photographed, mapped, and described, and a sequence of depositional and deformational events established for each trench. The McCabe Place trench exposed a sequence of volcaniclastic deposits overlain by soils and alluvial deposits separated by three unconformities. Six normal faults and two possible reverse faults deformed the exposed strata. Crosscutting relations indicated that up to five earthquakes occurred on a blind reverse fault, and a microprobe analysis of lapilli suggested that the earliest faulting occurred after 47,000 years before present. The Hessler Flat trench exposure revealed weathered bedrock that abuts loess and colluvium deposits and is overlain by soil, an upper sequence of loess, and colluvium. The latter two units bury a distinctive paloesol.

  19. Assessment of Climate Change Impacts on Agricultural Water Demands and Crop Yields in California's Central Valley

    NASA Astrophysics Data System (ADS)

    Tansey, M. K.; Flores-Lopez, F.; Young, C. A.; Huntington, J. L.

    2012-12-01

    Long term planning for the management of California's water resources requires assessment of the effects of future climate changes on both water supply and demand. Considerable progress has been made on the evaluation of the effects of future climate changes on water supplies but less information is available with regard to water demands. Uncertainty in future climate projections increases the difficulty of assessing climate impacts and evaluating long range adaptation strategies. Compounding the uncertainty in the future climate projections is the fact that most readily available downscaled climate projections lack sufficient meteorological information to compute evapotranspiration (ET) by the widely accepted ASCE Penman-Monteith (PM) method. This study addresses potential changes in future Central Valley water demands and crop yields by examining the effects of climate change on soil evaporation, plant transpiration, growth and yield for major types of crops grown in the Central Valley of California. Five representative climate scenarios based on 112 bias corrected spatially downscaled CMIP 3 GCM climate simulations were developed using the hybrid delta ensemble method to span a wide range future climate uncertainty. Analysis of historical California Irrigation Management Information System meteorological data was combined with several meteorological estimation methods to compute future solar radiation, wind speed and dew point temperatures corresponding to the GCM projected temperatures and precipitation. Future atmospheric CO2 concentrations corresponding to the 5 representative climate projections were developed based on weighting IPCC SRES emissions scenarios. The Land, Atmosphere, and Water Simulator (LAWS) model was used to compute ET and yield changes in the early, middle and late 21st century for 24 representative agricultural crops grown in the Sacramento, San Joaquin and Tulare Lake basins. Study results indicate that changes in ET and yield vary

  20. Chemical quality of ground water in the central Sacramento Valley, California

    USGS Publications Warehouse

    Fogelman, Ronald P.

    1978-01-01

    The study area includes about 1,200 square miles in the central Sacramento Valley adjacent to the Sacramento River from Knights Landing to Los Molinos, Calif. With recent agricultural development in the area, additional land has been brought under irrigation from land which had been used primarily for dry farming and grazing. This report documents the chemical character of the ground water prior to water-level declines resulting from extensive pumping for irrigation or to changes caused by extensive use of imported surface water. Chemical analyses of samples from 209 wells show that most of the area is underlain by ground water of a quality suitable for most agricultural and domestic purposes. Most of the water sampled in the area has dissolved-solids concentrations ranging from 100 to 700 milligrams per liter. The general water types for the area are a calcium magnesium bicarbonate or magnesium calcium bicarbonate and there are negligible amounts of toxic trace elements. (Woodard-USGS)

  1. Ground-water conditions in southern Utah Valley and Goshen Valley, Utah

    USGS Publications Warehouse

    Cordova, R.M.

    1970-01-01

    The investigation of ground-water conditions in southern Utah Valley and Goshen Valley, Utah, was made by the U. S. Geological Survey as part of a cooperative program with the Utah Department of Natural Resources, Division of Water Rights, to investigate the water resources of the State. The purposes of the investigation were to (1) determine the occurrence, recharge, discharge, movement, storage, chemical quality, and availability of ground water; (2) appraise the effects of increased withdrawal of water from wells; and (3) evaluate the effect of the Central Utah Project on the ground-water reservoir and the water supply of Utah Lake.This report presents a description of the aquifer system in the two valleys, a detailed description of the ground-water resources, and conclusions about potential development and its effect on the hydrologic conditions in the valleys. Two supplementary reports are products of the investigation. A basic-data release (Cordova, 1969) contains most of the basic data collected for the investigation, including well characteristics, drillers' logs, water levels, pumpage from wells, chemical analyses of ground and surface waters, and discharge of selected springs, drains, and streams. An interpretive report (Cordova and Mower, 1967) contains the results of a large-scale aquifer test in southern Utah Valley.

  2. A comprehensive analysis of high-magnitude streamflow and trends in the Central Valley, California

    NASA Astrophysics Data System (ADS)

    Kocis, T. N.; Dahlke, H. E.

    2017-12-01

    California's climate is characterized by the largest precipitation and streamflow variability observed within the conterminous US. This, combined with chronic groundwater overdraft of 0.6-3.5 km3 yr-1, creates the need to identify additional surface water sources available for groundwater recharge using methods such as agricultural groundwater banking, aquifer storage and recovery, and spreading basins. High-magnitude streamflow, i.e. flow above the 90th percentile, that exceeds environmental flow requirements and current surface water allocations under California water rights, could be a viable source of surface water for groundwater banking. Here, we present a comprehensive analysis of the magnitude, frequency, duration and timing of high-magnitude streamflow (HMF "metrics") over multiple time periods for 93 stream gauges covering the Sacramento, San Joaquin and Tulare basins in California. In addition, we present trend analyses conducted on the same dataset and all HMF metrics using generalized additive models, the Mann-Kendall trend test, and the Signal to Noise Ratio test. The results of the comprehensive analysis show, in short, that in an average year with HMF approximately 3.2 km3 of high-magnitude flow is exported from the entire Central Valley to the Sacramento-San Joaquin Delta, often at times when environmental flow requirements of the Delta and major rivers are exceeded. High-magnitude flow occurs, on average, during 7 and 4.7 out of 10 years in the Sacramento River and the San Joaquin-Tulare Basins, respectively, from just a few storm events (5-7 1-day peak events) lasting for a total of 25-30 days between November and April. Preliminary trend tests suggest that all HMF metrics show limited change over the last 50 years. As a whole, the results suggest that there is sufficient unmanaged surface water physically available to mitigate long-term groundwater overdraft in the Central Valley.

  3. Wild food plants and wild edible fungi in two valleys of the Qinling Mountains (Shaanxi, central China).

    PubMed

    Kang, Yongxiang; Łuczaj, Łukasz; Kang, Jin; Zhang, Shijiao

    2013-04-15

    The aim of the study was to investigate knowledge and use of wild food plants in two mountain valleys separated by Mount Taibai--the highest peak of northern China and one of its biodiversity hotspots, each adjacent to species-rich temperate forest vegetation. Seventy two free lists were collected among the inhabitants of two mountain valleys (36 in each). All the studied households are within walking distance of primary forest vegetation, however the valleys differed in access to urban centers: Houzhenzi is very isolated, and the Dali valley has easier access to the cities of central Shaanxi. Altogether, 185 wild food plant species and 17 fungi folk taxa were mentioned. The mean number of freelisted wild foods was very high in Houzhenzi (mean 25) and slightly lower in Dali (mean 18). An average respondent listed many species of wild vegetables, a few wild fruits and very few fungi. Age and male gender had a positive but very low effect on the number of taxa listed.Twelve taxa of wild vegetables (Allium spp., Amaranthus spp., Caryopteris divaricata, Helwingia japonica, Matteucia struthiopteris, Pteridium aquilinum, Toona sinensis, Cardamine macrophylla, Celastrus orbiculatus, Chenopodium album, Pimpinella sp., Staphylea bumalda &S. holocarpa), two species of edible fruits (Akebia trifoliata, Schisandra sphenanthera) and none of the mushrooms were freelisted by at least half of the respondents in one or two of the valleys. The high number of wild vegetables listed is due to the high cultural position of this type of food in China compared to other parts of the world, as well as the high biodiversity of the village surroundings. A very high proportion of woodland species (42%, double the number of the ruderal species used) among the listed taxa is contrary to the general stereotype that wild vegetables in Asia are mainly ruderal species. The very low interest in wild mushroom collecting is noteworthy and is difficult to explain. It may arise from the easy access to

  4. Reconnaissance geology of the Central Mastuj Valley, Chitral State, Pakistan

    USGS Publications Warehouse

    Stauffer, Karl W.

    1975-01-01

    The Mastuj Valley in Chitral State is a part of the Hindu Kush Range, and is one of the structurally most complicated areas in northern Pakistan. Sedimentary rocks ranging from at least Middle Devonian to Cretaceous, and perhaps Early Tertiary age lie between ridge-forming granodiorite intrusions and are cut by thrust faults. The thrust planes dip 10? to 40? to the north- west. Movement of the upper thrust plates has been toward the southeast relative to the lower blocks. If this area is structurally typical of the Hindu-Kush and Karakoram Ranges, then these mountains are much more tectonically disturbed than previously recorded, and suggest compression on a scale compatible with the hypothesis that the Himalayan, Karakoram, and Hindu Kush Ranges form part of a continental collision zone. The thrust faults outline two plates consisting of distinctive sedimentary rocks. The lower thrust plate is about 3,000 feet thick and consists of the isoclinally folded Upper Cretaceous to perhaps lower Tertiary Reshun Formation. It has overridden the Paleozoic metasedimentary rocks of the Chitral Slate unit. This thrust plate is, in turn, overridden by an 8,000-foot thick sequence consisting largely of Devonian to Carboniferous limestones and quartzites. A key factor in the tectonic processes has been the relatively soft and plastic lithology of the siltstone layers in the Reshun Formation which have acted as lubricants along the principal thrust faults, where they are commonly found today as fault slices and smears. The stratigraphic sequence, in the central Mastuj Valley was tentatively divided into 9 mapped units. The fossiliferous shales and carbonates of the recently defined Shogram Formation and the clastlcs of the Reshun Formation have been fitted into a sequence of sedimentary rocks that has a total thick- ness of at least 13,000 feet and ranges in age from Devonian to Neogene. Minerals of potential economic significance include antimony sulfides which have been mined

  5. Evidence for a Putative Impact Structure in Palm Valley, Central Australia

    NASA Astrophysics Data System (ADS)

    Hamacher, D. W.; O'Neill, C.; Buchel, A.; Britton, T. R.

    2010-07-01

    Introduction: We present evidence supporting the impact origin of a circular structure located in Palm Valley, Central Australia (24° 03' 06'' S, 132° 42' 34'' E). The ~280 m wide structure was discovered using a combination of Google Maps and a local Arrernte Aboriginal oral tradition regarding a star that fell into a waterhole called Puka in Palm Valley, Northern Territory [1][2] (see [3] for details of the discovery). Geophysical Evidence: A survey of the structure in September 2009 collected magnetic, gravity and topographic data. Geophysical modeling of the data revealed the structure has a bowl-shaped subsurface morphology, as expected for a simple impact crater. Though the structure sits within the Finke Gorge system, the models do not support an erosional origin for the structure, as no buried channels are observed. Nor does the modeling fit a volcanic origin, as the density structure at depth is consistent with fractured sandstone/sediments. Geological Evidence: One channel runs out of the crater to the south, consistent with outflow from crater-filling events, but again not with an erosional origin for the structure itself. The microstructure of rock samples collected from the site revealed the presence of planar deformation features in the quartz grains. The coincident angle of the fractures is consistent with the crystallographic fracture directions under mild-end shocks. These grains probably represent local focusing of stress as the shock wave moved through the heterogeneous grain matrix, suggesting the conditions were right for the shock pressure to locally exceed the ~7.5 GPa required to form the features, even though the bulk of the shock pressure was much less. Conclusion: Based on the level of erosion and the absence of shatter cones and meteorite fragments, we estimate the structure's age to be in the millions of years. While the presence of shocked-quartz is a direct indicator of a cosmic impact, we cannot rule out that the quartz was

  6. Chronology, sedimentology, and microfauna of groundwater discharge deposits in the central Mojave Desert, Valley Wells, California

    USGS Publications Warehouse

    Pigati, J.S.; Miller, D.M.; Bright, J.E.; Mahan, S.A.; Nekola, J.C.; Paces, J.B.

    2011-01-01

    groundwater supported persistent and long-lived desert wetlands in many broad valleys and basins in the American Southwest. When active, these systems provided important food and water sources for local fauna, supported hydrophilic and phreatophytic vegetation, and acted as catchments for eolian and alluvial sediments. Desert wetlands are represented in the geologic record by groundwater discharge deposits, which are also called spring or wetland deposits. Groundwater discharge deposits contain information on the timing and magnitude of past changes in water-table levels and, thus, are a source of paleohydrologic and paleoclimatic information. Here, we present the results of an investigation of extensive groundwater discharge deposits in the central Mojave Desert at Valley Wells, California. We used geologic mapping and stratigraphic relations to identify two distinct wetland sequences at Valley Wells, which we dated using radiocarbon, luminescence, and uranium-series techniques. We also analyzed the sediments and microfauna (ostracodes and gastropods) to reconstruct the specific environments in which they formed. Our results suggest that the earliest episode of high water-table conditions at Valley Wells began ca. 60 ka (thousands of calendar yr B.P.), and culminated in peak discharge between ca. 40 and 35 ka. During this time, cold (4-12 ??C) emergent groundwater supported extensive wetlands that likely were composed of a wet, sedge-rush-tussock meadow mixed with mesic riparian forest. After ca. 35 ka, the water table dropped below the ground surface but was still shallow enough to support dense stands of phreatophytes through the Last Glacial Maximum (LGM). The water table dropped further after the LGM, and xeric conditions prevailed until modest wetlands returned briefly during the Younger Dryas cold event (13.0-11.6 ka). We did not observe any evidence of wet conditions during the Holocene at Valley Wells. The timing of these fluctuations is consistent with

  7. Chronology, sedimentology, and microfauna of groundwater discharge deposits in the central Mojave Desert, Valley Wells, California

    USGS Publications Warehouse

    Pigati, Jeffrey S.; Miller, David M.; Bright, Jordon E.; Mahan, Shannon; Nekola, Jeffrey C.; Paces, James B.

    2011-01-01

    During the late Pleistocene, emergent groundwater supported persistent and long-lived desert wetlands in many broad valleys and basins in the American Southwest. When active, these systems provided important food and water sources for local fauna, supported hydrophilic and phreatophytic vegetation, and acted as catchments for eolian and alluvial sediments. Desert wetlands are represented in the geologic record by groundwater discharge deposits, which are also called spring or wetland deposits. Groundwater discharge deposits contain information on the timing and magnitude of past changes in water-table levels and, thus, are a source of paleohydrologic and paleoclimatic information. Here, we present the results of an investigation of extensive groundwater discharge deposits in the central Mojave Desert at Valley Wells, California. We used geologic mapping and stratigraphic relations to identify two distinct wetland sequences at Valley Wells, which we dated using radiocarbon, luminescence, and uranium-series techniques. We also analyzed the sediments and microfauna (ostracodes and gastropods) to reconstruct the specific environments in which they formed. Our results suggest that the earliest episode of high water-table conditions at Valley Wells began ca. 60 ka (thousands of calendar yr B.P.), and culminated in peak discharge between ca. 40 and 35 ka. During this time, cold (4–12 °C) emergent groundwater supported extensive wetlands that likely were composed of a wet, sedge-rush-tussock meadow mixed with mesic riparian forest. After ca. 35 ka, the water table dropped below the ground surface but was still shallow enough to support dense stands of phreatophytes through the Last Glacial Maximum (LGM). The water table dropped further after the LGM, and xeric conditions prevailed until modest wetlands returned briefly during the Younger Dryas cold event (13.0–11.6 ka). We did not observe any evidence of wet conditions during the Holocene at Valley Wells. The timing

  8. Effects of hydrologic infrastructure on flow regimes of California's Central Valley rivers: Implications for fish populations

    USGS Publications Warehouse

    Brown, Larry R.; Bauer, Marissa L.

    2010-01-01

    Alteration of natural flow regimes is generally acknowledged to have negative effects on native biota; however, methods for defining ecologically appropriate flow regimes in managed river systems are only beginning to be developed. Understanding how past and present water management has affected rivers is an important part of developing such tools. In this paper, we evaluate how existing hydrologic infrastructure and management affect streamflow characteristics of rivers in the Central Valley, California and discuss those characteristics in the context of habitat requirements of native and alien fishes. We evaluated the effects of water management by comparing observed discharges with estimated discharges assuming no water management ("full natural runoff"). Rivers in the Sacramento River drainage were characterized by reduced winter–spring discharges and augmented discharges in other months. Rivers in the San Joaquin River drainage were characterized by reduced discharges in all months but particularly in winter and spring. Two largely unaltered streams had hydrographs similar to those based on full natural runoff of the regulated rivers. The reduced discharges in the San Joaquin River drainage streams are favourable for spawning of many alien species, which is consistent with observed patterns of fish distribution and abundance in the Central Valley. However, other factors, such as water temperature, are also important to the relative success of native and alien resident fishes. As water management changes in response to climate change and societal demands, interdisciplinary programs of research and monitoring will be essential for anticipating effects on fishes and to avoid unanticipated ecological outcomes.

  9. Principal facts for gravity stations in the Antelope Valley-Bedell Flat area, west-central Nevada

    USGS Publications Warehouse

    Jewel, Eleanore B.; Ponce, David A.; Morin, Robert L.

    2000-01-01

    In April 2000 the U.S. Geological Survey (USGS) established 211 gravity stations in the Antelope Valley and Bedell Flat area of west-central Nevada (see figure 1). The stations were located about 15 miles north of Reno, Nevada, southwest of Dogskin Mountain, and east of Petersen Mountain, concentrated in Antelope Valley and Bedell Flat (figure 2). The ranges in this area primarily consist of normal-faulted Cretaceous granitic rocks, with some volcanic and metavolcanic rocks. The purpose of the survey was to characterize the hydrogeologic framework of Antelope Valley and Bedell Flat in support of future hydrologic investigations. The information developed during this study can be used in groundwater models. Gravity data were collected between latitude 39°37.5' and 40°00' N and longitude 119°37.5' and 120°00' W. The stations were located on the Seven Lakes Mountain, Dogskin Mountain, Granite Peak, Bedell Flat, Fraser Flat, and Reno NE 7.5 minute quadrangles. All data were tied to secondary base station RENO-A located on the campus of the University of Nevada at Reno (UNR) in Reno, Nevada (latitude 39°32.30' N, longitude 119°48.70' W, observed gravity value 979674.69 mGal). The value for observed gravity was calculated by multiple ties to the base station RENO (latitude 39°32.30' N, longitude 119°48.70' W, observed gravity value 979674.65 mGal), also on the UNR campus. The isostatic gravity map (figure 3) includes additional data sets from the following sources: 202 stations from a Geological Survey digital data set (Ponce, 1997), and 126 stations from Thomas C. Carpenter (written commun., 1998).

  10. Hydrogeologic framework and estimates of groundwater storage for the Hualapai Valley, Detrital Valley, and Sacramento Valley basins, Mohave County, Arizona

    USGS Publications Warehouse

    Truini, Margot; Beard, L. Sue; Kennedy, Jeffrey; Anning, Dave W.

    2013-01-01

    We have investigated the hydrogeology of the Hualapai Valley, Detrital Valley, and Sacramento Valley basins of Mohave County in northwestern Arizona to develop a better understanding of groundwater storage within the basin fill aquifers. In our investigation we used geologic maps, well-log data, and geophysical surveys to delineate the sedimentary textures and lithology of the basin fill. We used gravity data to construct a basin geometry model that defines smaller subbasins within the larger basins, and airborne transient-electromagnetic modeled results along with well-log lithology data to infer the subsurface distribution of basin fill within the subbasins. Hydrogeologic units (HGUs) are delineated within the subbasins on the basis of the inferred lithology of saturated basin fill. We used the extent and size of HGUs to estimate groundwater storage to depths of 400 meters (m) below land surface (bls). The basin geometry model for the Hualapai Valley basin consists of three subbasins: the Kingman, Hualapai, and southern Gregg subbasins. In the Kingman subbasin, which is estimated to be 1,200 m deep, saturated basin fill consists of a mixture of fine- to coarse-grained sedimentary deposits. The Hualapai subbasin, which is the largest of the subbasins, contains a thick halite body from about 400 m to about 4,300 m bls. Saturated basin fill overlying the salt body consists predominately of fine-grained older playa deposits. In the southern Gregg subbasin, which is estimated to be 1,400 m deep, saturated basin fill is interpreted to consist primarily of fine- to coarse-grained sedimentary deposits. Groundwater storage to 400 m bls in the Hualapai Valley basin is estimated to be 14.1 cubic kilometers (km3). The basin geometry model for the Detrital Valley basin consists of three subbasins: northern Detrital, central Detrital, and southern Detrital subbasins. The northern and central Detrital subbasins are characterized by a predominance of playa evaporite and fine

  11. Rock avalanche deposits in Alai Valley, Central Asia: misinterpretation of glacial record

    NASA Astrophysics Data System (ADS)

    Reznichenko, Natalya; Davies, Tim; Robinson, Tom; De Pascale, Gregory

    2013-04-01

    The reconstruction of Quaternary glaciations has been restricted by conventional approaches with resulting contradictions in interpretation of the regional glacial record, that recently have been subjected to critical re-evaluation. Along with uncertainties in dating techniques and their applicability to particular landforms (Kirkbride and Winkler, 2012), it has recently been demonstrated that the presence of rock avalanche debris in a landform can be unequivocally detected; this allows for the first time definitive identification of and distinction between glacial moraines and landslide deposits. It also identifies moraines that have formed due to rock avalanche deposition on glaciers, possibly with no associated climatic signal (Reznichenko et al., 2012). Confusion between landslide deposits and moraines is evident for ranges in Central Asia (e.g., Hewitt, 1999) where the least-studied glacial record is selectively correlated with established glacial chronologies in Alpine ranges, which in turn masks the actual glacial extent and their responses to climate change, tectonics and landsliding activity. We describe examples in the glaciated Alai Valley, large intermountain depression between the Zaalay Range of the Northern Pamir and the Alay Range of the Southern Tien-Shan, showing that some large Quaternary deposits classically interpreted as moraines are of rock avalanche origin. Sediment from these deposits has been tested for the presence of agglomerates that are only produced under high stress conditions during rock avalanche motion, and are absent from glacial sediments (Reznichenko et al., 2012). This reveals that morphologically-similar deposits have radically different geneses: rock avalanche origin for a deposit in the Komansu river catchment and glacial origin for deposits in the Ashiktash and Kyzylart catchments. The enormous Komansu rock avalanche deposit, probably triggered by a rupture of the Main Pamir thrust, currently covers about 100 km2 with a

  12. HLA haplotype map of river valley populations with hemochromatosis traced through five centuries in Central Sweden.

    PubMed

    Olsson, K Sigvard; Ritter, Bernd; Hansson, Norbeth; Chowdhury, Ruma R

    2008-07-01

    The hemochromatosis mutation, C282Y of the HFE gene, seems to have originated from a single event which once occurred in a person living in the north west of Europe carrying human leukocyte antigen (HLA)-A3-B7. In descendants of this ancestor also other haplotypes appear probably caused by local recombinations and founder effects. The background of these associations is unknown. Isolated river valley populations may be fruitful for the mapping of genetic disorders such as hemochromatosis. In this study, we try to test this hypothesis in a study from central Sweden where the haplotyope A1-B8 was common. HLA haplotypes and HFE mutations were studied in hemochromatosis patients with present or past parental origin in a sparsely populated (1/km(2)) rural district (n = 8366 in the year of 2005), in central Sweden. Pedigrees were constructed from the Swedish church book registry. Extended haplotypes were studied to evaluate origin of recombinations. There were 87 original probands, 36 females and 51 males identified during 30 yr, of whom 86% carried C282Y/C282Y and 14% C282Y/H63D. Of 32 different HLA haplotypes A1-B8 was the most common (34%), followed by A3-B7 (16%), both in strong linkage disequilibrium with controls, (P < 0.001). Twenty-nine different families with A1-B8 had a common founder origin 15 generations ago in small bottleneck populations of the late 16th century. A second A1-B8 founder born 1655 was of Norwegian origin. Most of the A3 carriers (n = 26) had a common founder origin 16 generations ago in an even smaller nearby river valley. A fourth founder family carrying HLA-A2 seems to have originated from a recombination along the descendant lines from the A3 ancestor supported by extended haplotype studies. A1-haplotypes with alleles at the B locus different from B8 had a similar recombination origin as HLA-A2 alleles and a common founder origin 11 generations ago. The intergenerational time interval averaged 35.5 +/- 7.9 yr in men and 31.9 +/- 5.9 in

  13. Comparison of sediment supply to San Francisco Bay from watersheds draining the Bay Area and the Central Valley of California

    USGS Publications Warehouse

    McKee, L.J.; Lewicki, M.; Schoellhamer, D.H.; Ganju, N.K.

    2013-01-01

    Quantifying suspended sediment loads is important for managing the world's estuaries in the context of navigation, pollutant transport, wetland restoration, and coastal erosion. To address these needs, a comprehensive analysis was completed on sediment supply to San Francisco Bay from fluvial sources. Suspended sediment, optical backscatter, velocity data near the head of the estuary, and discharge data obtained from the output of a water balance model were used to generate continuous suspended sediment concentration records and compute loads to the Bay from the large Central Valley watershed. Sediment loads from small tributary watersheds around the Bay were determined using 235 station-years of suspended sediment data from 38 watershed locations, regression analysis, and simple modeling. Over 16 years, net annual suspended sediment load to the head of the estuary from its 154,000 km2 Central Valley watershed varied from 0.13 to 2.58 (mean = 0.89) million metric t of suspended sediment, or an average yield of 11 metric t/km2/yr. Small tributaries, totaling 8145 km2, in the nine-county Bay Area discharged between 0.081 and 4.27 (mean = 1.39) million metric t with a mean yield of 212 metric t/km2/yr. The results indicate that the hundreds of urbanized and tectonically active tributaries adjacent to the Bay, which together account for just 5% of the total watershed area draining to the Bay and provide just 7% of the annual average fluvial flow, supply 61% of the suspended sediment. The small tributary loads are more variable (53-fold between years compared to 21-fold for the inland Central Valley rivers) and dominated fluvial sediment supply to the Bay during 10 out of 16 yr. If San Francisco Bay is typical of other estuaries in active tectonic or climatically variable coastal regimes, managers responsible for water quality, dredging and reusing sediment accumulating in shipping channels, or restoring wetlands in the world's estuaries may need to more carefully

  14. Structural and lithologic study of northern coast ranges and Sacramento Valley, California

    NASA Technical Reports Server (NTRS)

    Rich, E. I. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. Analysis of ERTS-1 imagery of the Northern California Coast Ranges has disclosed a potential relation between a heretofore unrecognized fracture system and known deposits of mercury and geothermally active areas in the Coast Range and between oil and gas fields in the Sacramento Valley. Three potentially important systems of linear elements within the Coast Ranges, detected on ERTS-1 imagery, may represent fault systems or zones of shearing because topographic offset and stratigraph disruption can be seen along one or two of the lineations. One of the systems in subparallel to the San Andreas fault and is confined to the Pacific Coastal Belt. Another set is confined to the central core of the Coast Ranges. The third set of linear features (Valley System) has not heretofore been recognized. Some of the known mercury deposits and geothermally active areas near Clear Lake, in the Coast Ranges, are along the Valley System or at the intersection of the Central and Valley Systems. The plotted locations of some of the oil and gas fields in the Sacramento Valley are associated with the Valley and/or Central Systems. If these relations prove reliable, the ERTS-1 imagery may prove to be an extremely useful exploration tool.

  15. Assessment of regional change in nitrate concentrations in groundwater in the Central Valley, California, USA, 1950s-2000s

    USGS Publications Warehouse

    Burow, Karen R.; Jurgens, Bryant C.; Belitz, Kenneth; Dubrovsky, Neil M.

    2013-01-01

    A regional assessment of multi-decadal changes in nitrate concentrations was done using historical data and a spatially stratified non-biased approach. Data were stratified into physiographic subregions on the basis of geomorphology and soils data to represent zones of historical recharge and discharge patterns in the basin. Data were also stratified by depth to represent a shallow zone generally representing domestic drinking-water supplies and a deep zone generally representing public drinking-water supplies. These stratifications were designed to characterize the regional extent of groundwater with common redox and age characteristics, two factors expected to influence changes in nitrate concentrations over time. Overall, increasing trends in nitrate concentrations and the proportion of nitrate concentrations above 5 mg/L were observed in the east fans subregion of the Central Valley. Whereas the west fans subregion has elevated nitrate concentrations, temporal trends were not detected, likely due to the heterogeneous nature of the water quality in this area and geologic sources of nitrate, combined with sparse and uneven data coverage. Generally low nitrate concentrations in the basin subregion are consistent with reduced geochemical conditions resulting from low permeability soils and higher organic content, reflecting the distal portions of alluvial fans and historical groundwater discharge areas. Very small increases in the shallow aquifer in the basin subregion may reflect downgradient movement of high nitrate groundwater from adjacent areas or overlying intensive agricultural inputs. Because of the general lack of regionally extensive long-term monitoring networks, the results from this study highlight the importance of placing studies of trends in water quality into regional context. Earlier work concluded that nitrate concentrations were steadily increasing over time in the eastern San Joaquin Valley, but clearly those trends do not apply to other

  16. Spatial and seasonal variability of base flow in the Verde Valley, central Arizona, 2007 and 2011

    USGS Publications Warehouse

    Garner, Bradley D.; Bills, Donald J.

    2012-01-01

    Synoptic base-flow surveys were conducted on streams in the Verde Valley, central Arizona, in June 2007 and February 2011 by the U.S. Geological Survey (USGS), in cooperation with the Verde River Basin Partnership, the Town of Clarkdale, and Yavapai County. These surveys, also known as seepage runs, measured streamflow under base-flow conditions at many locations over a short period of time. Surveys were conducted on a segment of the Verde River that flows through the Verde Valley, between USGS streamflow-gaging stations 09504000 and 09506000, a distance of 51 river miles. Data from the surveys were used to investigate the dominant controls on Verde River base flow, spatial variability in gaining and losing reaches, and the effects that human alterations have on base flow in the surface-water system. The most prominent human alterations in the Verde Valley are dozens of surface-water diversions from streams, including gravity-fed ditch diversions along the Verde River.Base flow that entered the Verde River from the tributary streams of Oak Creek, Beaver Creek, and West Clear Creek was found to be a major source of base flow in the Verde River. Groundwater discharge directly into the Verde River near these three confluences also was an important contributor of base flow to the Verde River, particularly near the confluence with Beaver Creek. An examination of individual reaches of the Verde River in the Verde Valley found three reaches (largely unaffected by ditch diversions) exhibiting a similar pattern: a small net groundwater discharge in February 2011 (12 cubic feet per second or less) and a small net streamflow loss in June 2007 (11 cubic feet per second or less). Two reaches heavily affected by ditch diversions were difficult to interpret because of the large number of confounding human factors. Possible lower and upper bounds of net groundwater flux were calculated for all reaches, including those heavily affected by ditches.

  17. Human effects on the hydrologic system of the Verde Valley, central Arizona, 1910–2005 and 2005–2110, using a regional groundwater flow model

    USGS Publications Warehouse

    Garner, Bradley D.; Pool, D.R.; Tillman, Fred D.; Forbes, Brandon T.

    2013-01-01

    Water budgets were developed for the Verde Valley of central Arizona in order to evaluate the degree to which human stresses have affected the hydrologic system and might affect it in the future. The Verde Valley is a portion of central Arizona wherein concerns have been raised about water availability, particularly perennial base flow of the Verde River. The Northern Arizona Regional Groundwater Flow Model (NARGFM) was used to generate the water budgets and was run in several configurations for the 1910–2005 and 2005–2110 time periods. The resultant water budgets were subtracted from one another in order to quantify the relative changes that were attributable solely to human stresses; human stresses included groundwater withdrawals and incidental and artificial recharge but did not include, for example, human effects on the global climate. Three hypothetical and varied conditions of human stresses were developed and applied to the model for the 2005–2110 period. On the basis of this analysis, human stresses during 1910–2005 were found to have already affected the hydrologic system of the Verde Valley, and human stresses will continue to affect the hydrologic system during 2005–2110. Riparian evapotranspiration decreased and underflow into the Verde Valley increased because of human stresses, and net groundwater discharge to the Verde River in the Verde Valley decreased for the 1910–2005 model runs. The model also showed that base flow at the upstream end of the study area, as of 2005, was about 4,900 acre-feet per year less than it would have been in the absence of human stresses. At the downstream end of the Verde Valley, base flow had been reduced by about 10,000 acre-feet per year by the year 2005 because of human stresses. For the 2005–2110 period, the model showed that base flow at the downstream end of the Verde Valley may decrease by an additional 5,400 to 8,600 acre-feet per year because of past, ongoing, and hypothetical future human

  18. Wildlife Diversity in Valley-Foothill Riparian Habitat: North Central vs. Central Coast California

    Treesearch

    William D. Tietje; Reginald H. Barrett; Eric B. Kleinfelter; Brett T. Carré

    1991-01-01

    Habitat characteristics and diversity of terrestrial vertebrates were studied September 1989 to August 1990 in valley-foothill riparian habitat on two study areas: Dye Creek, Tehama County, and Avenales Ranch, San Luis Obispo County, California. The assumption considered was that differences between study areas in physical and vegetation characteristics would be...

  19. Evaluating spatial and temporal variations of rainfall erosivity, case of Central Rift Valley of Ethiopia

    NASA Astrophysics Data System (ADS)

    Meshesha, Derege Tsegaye; Tsunekawa, Atsushi; Tsubo, Mitsuru; Haregeweyn, Nigussie; Adgo, Enyew

    2015-02-01

    Land degradation in many Ethiopian highlands occurs mainly due to high rainfall erosivity and poor soil conservation practices. Rainfall erosivity is an indicator of the precipitation energy and ability to cause soil erosion. In Central Rift Valley (CRV) of Ethiopia, where the climate is characterized as arid and semiarid, rainfall is the main driver of soil erosion that in turn causes a serious expansion in land degradation. In order to evaluate the spatial and temporal variability of rainfall erosivity and its impact on soil erosion, long-term rainfall data (1980-2010) was used, and the monthly Fournier index (FI) and the annual modified Fournier index (MFI) were applied. Student's t test analysis was performed particularly to examine statistical significances of differences in average monthly and annual erosivity values. The result indicated that, in a similar spatial pattern with elevation and rainfall amount, average annual erosivity is also found being higher in western highlands of the valley and gradually decreased towards the east. The long-term average annual erosivity (MFI) showed a general decreasing trend in recent 10 years (2000-2010) as compared to previous 20 years (1980-1999). In most of the stations, average erosivity of main rainy months (May, June, July, and August) showed a decreasing trend, whereby some of them (about 33.3 %) are statically significant at 90 and 95 % confidence intervals but with high variation in spatial pattern of changes. The overall result of the study showed that rainfall aggression (erosivity) in the region has a general decreasing trend in the recent decade as compared to previous decades, especially in the western highlands of the valley. Hence, it implies that anthropogenic factors such as land use change being coupled with topography (steep slope) have largely contributed to increased soil erosion rate in the region.

  20. Isotopic composition in precipitation and groundwater in the northern mountainous region of the Central Valley of Costa Rica.

    PubMed

    Sánchez-Murillo, Ricardo; Esquivel-Hernández, Germain; Sáenz-Rosales, Oscar; Piedra-Marín, Gilberto; Fonseca-Sánchez, Alicia; Madrigal-Solís, Helga; Ulloa-Chaverri, Franz; Rojas-Jiménez, Luis D; Vargas-Víquez, José A

    2017-03-01

    The linkage between precipitation and recharge is still poorly understood in the Central America region. This study focuses on stable isotopic composition in precipitation and groundwater in the northern mountainous region of the Central Valley of Costa Rica. During the dry season, rainfall samples corresponded to enriched events with high deuterium excess. By mid-May, the Intertropical Convergence Zone poses over Costa Rica resulting in a depletion of 18 O/ 16 O and 2 H/H ratios. A parsimonious four-variable regression model (r 2  = 0.52) was able to predict daily δ 18 O in precipitation. Air mass back trajectories indicated a combination of Caribbean Sea and Pacific Ocean sources, which is clearly depicted in groundwater isoscape. Aquifers relying on Pacific-originated recharge exhibited a more depleted pattern, whereas recharge areas relying on Caribbean parental moisture showed an enrichment trend. These results can be used to enhance modelling efforts in Central America where scarcity of long-term data limits water resources management plans.

  1. Wild food plants and wild edible fungi in two valleys of the Qinling Mountains (Shaanxi, central China)

    PubMed Central

    2013-01-01

    Background The aim of the study was to investigate knowledge and use of wild food plants in two mountain valleys separated by Mount Taibai – the highest peak of northern China and one of its biodiversity hotspots, each adjacent to species-rich temperate forest vegetation. Methods Seventy two free lists were collected among the inhabitants of two mountain valleys (36 in each). All the studied households are within walking distance of primary forest vegetation, however the valleys differed in access to urban centers: Houzhenzi is very isolated, and the Dali valley has easier access to the cities of central Shaanxi. Results Altogether, 185 wild food plant species and 17 fungi folk taxa were mentioned. The mean number of freelisted wild foods was very high in Houzhenzi (mean 25) and slightly lower in Dali (mean 18). An average respondent listed many species of wild vegetables, a few wild fruits and very few fungi. Age and male gender had a positive but very low effect on the number of taxa listed. Twelve taxa of wild vegetables (Allium spp., Amaranthus spp., Caryopteris divaricata, Helwingia japonica, Matteucia struthiopteris, Pteridium aquilinum, Toona sinensis, Cardamine macrophylla, Celastrus orbiculatus, Chenopodium album, Pimpinella sp., Staphylea bumalda &S. holocarpa), two species of edible fruits (Akebia trifoliata, Schisandra sphenanthera) and none of the mushrooms were freelisted by at least half of the respondents in one or two of the valleys. Conclusion The high number of wild vegetables listed is due to the high cultural position of this type of food in China compared to other parts of the world, as well as the high biodiversity of the village surroundings. A very high proportion of woodland species (42%, double the number of the ruderal species used) among the listed taxa is contrary to the general stereotype that wild vegetables in Asia are mainly ruderal species. The very low interest in wild mushroom collecting is noteworthy and is difficult to

  2. Data network, collection, and analysis in the Diamond Valley flow system, central Nevada

    USGS Publications Warehouse

    Knochenmus, Lari A.; Berger, David L.; Moreo, Michael T.; Smith, J. LaRue

    2011-01-01

    Future groundwater development and its effect on future municipal, irrigation, and alternative energy uses in the Diamond Valley flow system are of concern for officials in Eureka County, Nevada. To provide a better understanding of the groundwater resources, the U.S. Geological Survey, in cooperation with Eureka County, commenced a multi-phase study of the Diamond Valley flow system in 2005. Groundwater development primarily in southern Diamond Valley has resulted in water-level declines since the 1960s ranging from less than 5 to 100 feet. Groundwater resources in the Diamond Valley flow system outside of southern Diamond Valley have been relatively undeveloped. Data collected during phase 2 of the study (2006-09) included micrometeorological data at 4 evapotranspiration stations, 3 located in natural vegetation and 1 located in an agricultural field; groundwater levels in 95 wells; water-quality constituents in aquifers and springs at 21 locations; lithologic information from 7 recently drilled wells; and geophysical logs from 3 well sites. This report describes what was accomplished during phase 2 of the study, provides the data collected, and presents the approaches to strengthen relations between evapotranspiration rates measured at micrometeorological stations and spatially distributed groundwater discharge. This report also presents the approach to improve delineation of areas of groundwater discharge and describes the current methodology used to improve the accuracy of spatially distributed groundwater discharge rates in the Diamond Valley flow system.

  3. Glacial stages and post-glacial environmental evolution in the Upper Garonne valley, Central Pyrenees.

    PubMed

    Fernandes, M; Oliva, M; Palma, P; Ruiz-Fernández, J; Lopes, L

    2017-04-15

    The maximum glacial extent in the Central Pyrenees during the Last Glaciation is known to have occurred before the global Last Glacial Maximum, but the succession of cold events afterwards and their impact on the landscape are still relatively unknown. This study focuses on the environmental evolution in the upper valley of the Garonne River since the Last Glaciation. Geomorphological mapping allows analysis of the spatial distribution of inherited and current processes and landforms in the study area. The distribution of glacial records (moraines, till, erratic boulders, glacial thresholds) suggests the existence of four glacial stages, from the maximum expansion to the end of the glaciation. GIS modeling allows quantification of the Equilibrium Line Altitude, extent, thickness and volume of ice in each glacial stage. During the first stage, the Garonne glacier reached 460m in the Loures-Barousse-Barbazan basin, where it formed a piedmont glacier 88km from the head and extended over 960km 2 . At a second stage of glacier stabilization during the deglaciation process, the valley glaciers were 12-23km from the head until elevations of 1000-1850m, covering an area of 157km 2 . Glaciers during stage three remained isolated in the upper parts of the valley, at heights of 2050-2200m and 2.6-4.5km from the head, with a glacial surface of 16km 2 . In stage four, cirque glaciers were formed between 2260m and 2590m, with a length of 0.4-2km and a glacial area of 5.7km 2 . Also, the wide range of periglacial, slope, nival and alluvial landforms existing in the formerly glaciated environments allows reconstruction of the post-glacial environmental dynamics in the upper Garonne basin. Today, the highest lands are organized following three elevation belts: subnival (1500-1900m), nival (1900-2300m) and periglacial/cryonival (2300-2800m). Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Assessing Child Obesity and Physical Activity in a Hard-to-Reach Population in California’s Central Valley, 2012–2013

    PubMed Central

    Camacho-Gomez, Rosa; Sadeghi, Banefsheh; Kaiser, Lucia; German, J. Bruce; de la Torre, Adela

    2015-01-01

    Introduction In California’s agricultural Central Valley, the rate of childhood obesity is higher than the national average. Adequate physical activity contributes to obesity prevention and its assessment is useful to evaluate the impact of interventions. Methods Niños Sanos, Familia Sana (Healthy Children, Healthy Family [NSFS]) uses community-based participatory research to implement an intervention program to reduce childhood obesity among people of Mexican origin in the Central Valley. Anthropometric measurements were conducted on more than 650 children enrolled in NSFS. Physical activity data from a subgroup of children aged 4 to 7 years (n = 134) were collected via a wearable accelerometer. Results Children were classified on the basis of age and sex-adjusted body mass index as healthy weight (57.7%); overweight (19.3%), or obese (23%). Logistic regression showed that moderate to vigorous physical activity (MVPA) was associated with a child’s likelihood of having a healthy BMI (odds ratio: 1.03; 95% CI, 1.01–1.05; P = .017). Conclusion NSFS’s community-based participatory approach resulted in successful use of a commercial electronic device to measure physical activity quantity and quality in this hard-to-reach population. Promotion of adequate daily MVPA is an appropriate and necessary component of NSFS’s childhood obesity prevention strategy. PMID:26203815

  5. Distribution of glacial deposits, soils, and permafrost in Taylor Valley, Antarctica

    USGS Publications Warehouse

    Bockheim, James G.; Prentice, M.L.; McLeod, M.

    2008-01-01

    We provide a map of lower and central Taylor Valley, Antarctica, that shows deposits from Taylor Glacier, local alpine glaciers, and grounded ice in the Ross Embayment. From our electronic database, which includes 153 sites from the coast 50 km upvalley to Pearse Valley, we show the distribution of permafrost type and soil subgroups according to Soil Taxonomy. Soils in eastern Taylor Valley are of late Pleistocene age, cryoturbated due to the presence of ground ice or ice-cemented permafrost within 70 cm of the surface, and classified as Glacic and Typic Haploturbels. In central Taylor Valley, soils are dominantly Typic Anhyorthels of mid-Pleistocene age that have dry-frozen permafrost within the upper 70 cm. Salt-enriched soils (Salic Anhyorthels and Petrosalic Anhyorthels) are of limited extent in Taylor Valley and occur primarily on drifts of early Pleistocene and Pliocene age. Soils are less developed in Taylor Valley than in nearby Wright Valley, because of lesser salt input from atmospheric deposition and salt weathering. Ice-cemented permafrost is ubiquitous on Ross Sea, pre-Ross Sea, and Bonney drifts that occur within 28 km of the McMurdo coast. In contrast, dry-frozen permafrost is prevalent on older (???115 ky) surfaces to the west. ?? 2008 Regents of the University of Colorado.

  6. Meter-Scale Characteristics of Martian Channels and Valleys

    USGS Publications Warehouse

    Carr, M.H.; Malin, M.C.

    2000-01-01

    Mars Global Surveyor images, with resolutions as high as 1.5 m pixel, enable characterization of martian channels and valleys at resolutions one to two orders of magnitude better than was previously possible. A major surprise is the near-absence of valleys a few hundred meters wide and narrower. The almost complete absence of fine-scale valleys could be due to lack of precipitation, destruction of small valleys by erosion, or dominance of infiltration over surface runoff. V-shaped valleys with a central channel, such as Nanedi Vallis, provide compelling evidence for sustained or episodic flow of water across the surface. Larger valleys appear to have formed not by headward erosion as a consequence of groundwater sapping but by erosion from water sources upstream of the observed sections. The freshest appearing valleys have triangular cross sections, with talus from opposing walls meeting at the center of the valley. The relations suggest that the width of the valleys is controlled by the depth of incision and the angle of repose of the walls. The flat floors of less fresh-appearing valleys result primarily from later eolian fill. Several discontinuous valleys and lines of craters suggest massive subsurface solution or erosion. The climatic implications of the new images will remain obscure until the cause for the scarcity of fine-scale dissection is better understood. ?? 2000 Academic Press.

  7. Groundwater quality in the Borrego Valley, Central Desert, and Low-Use Basins of the Mojave and Sonoran Deserts, California

    USGS Publications Warehouse

    Parsons, Mary C.; Belitz, Kenneth

    2014-01-01

    Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s untreated groundwater quality and increases public access to groundwater-quality information. Selected groundwater basins in the Borrego Valley, Central Desert, and Low-Use Basins of the Mojave and Sonoran Deserts constitute one of the study units being evaluated.

  8. Comparison of Summer and Winter California Central Valley Aerosol Distributions from Lidar and MODIS Measurements

    NASA Technical Reports Server (NTRS)

    Lewis, Jasper R., Jr.; DeYoung, Russell J.; Chu, D. Allen

    2010-01-01

    Aerosol distributions from two aircraft lidar campaigns conducted in the California Central Valley are compared in order to identify seasonal variations. Aircraft lidar flights were conducted in June 2003 and February 2008. While the PM2.5 concentration is highest in the winter, the aerosol optical depth measured from MODIS is highest in the summer. A seasonal comparison shows that PM2.5 in the winter can exceed summer PM2.5 by 55%, while summer AOD exceeds winter AOD by 43%. Higher temperatures wildfires in the summer produce elevated aerosol layers that are detected by satellite measurements, but not surface particulate matter monitors. Measurements of the boundary layer height from lidar instruments are necessary to incorporate satellite measurements with air quality measurements.

  9. Large quaternary landslides in the central appalachian valley and ridge province near Petersburg, West Virginia

    USGS Publications Warehouse

    Southworth, C. Scott

    1988-01-01

    Geological mapping and photointerpretation of side-looking airborne radar images and color-infrared aerial photographs reveal two large Quaternary landslides in the Valley and Ridge province of the central Appalachians near Petersburg, W. Va. The Elkhorn Mountain rock avalanche occurs on the thrust-faulted northwestern flank of the Elkhorn Mountain anticlinorium. A minimum of 7 ?? 106 m3 of quartzite colluvium was transported more than 3 km from a 91 m high escarpment of Silurian Tuscarora Quartzite. The extensively vegetated deposit may owe, in part, its transport and weathering to periglacial conditions during the Pleistocene. In contrast, the Gap Mountain rock block slide is a single allochthonous block that is 1.2 km long, 0.6 km wide, and at least 60 m thick. The 43 ?? 106 m3 block is composed of limestone of the Helderberg Group and the Oriskany Sanstone of Early Devonian age. Planar detachment probably occurred along a dissolution bedding plane near the Shriver Chert and the Oriskany Sandstone contact. Failure probably was initiated by downcutting of the South Branch Potomac River during the Pleistocene. Landslides of this magnitude suggest accelerated erosion during periglacial climates in the Pleistocene. The recognition of these large slope failures may provide evidence of paleoclimatic conditions and, thereby, increase our understanding of the geomorphologic development of the Valley and Ridge province. ?? 1988.

  10. Geohydrology of the Valley-Fill Aquifers between the Village of Greene, Chenango County and Chenango Valley State Park, Broome County, New York

    USGS Publications Warehouse

    Hetcher-Aguila, Kari K.; Miller, Todd S.

    2005-01-01

    The confined aquifer is widely used by people living and working in the Chenango River valley. The confined aquifer consists of ice-contact sand and gravel, typically overlies bedrock, and underlies a confining unit consisting of lacustrine fine sand, silt, and clay. The confining unit is typically more than 100 feet thick in the central parts of the valley between Greene Landing Field and along the northern edge of the Chenango Valley State Park. The thickness of the confined aquifer is more than 40 feet near the Greene Landing Field.

  11. Dissolved Pesticide and Organic Carbon Concentrations Detected in Surface Waters, Northern Central Valley, California, 2001-2002

    USGS Publications Warehouse

    Orlando, James L.; Jacobson, Lisa A.; Kuivila, Kathryn

    2004-01-01

    Field and laboratory studies were conducted to determine the effects of pesticide mixtures on Chinook salmon under various environmental conditions in surface waters of the northern Central Valley of California. This project was a collaborative effort between the U.S. Geological Survey (USGS) and the University of California. The project focused on understanding the environmental factors that influence the toxicity of pesticides to juvenile salmon and their prey. During the periods January through March 2001 and January through May 2002, water samples were collected at eight surface water sites in the northern Central Valley of California and analyzed by the USGS for dissolved pesticide and dissolved organic carbon concentrations. Water samples were also collected by the USGS at the same sites for aquatic toxicity testing by the Aquatic Toxicity Laboratory at the University of California Davis; however, presentation of the results of these toxicity tests is beyond the scope of this report. Samples were collected to characterize dissolved pesticide and dissolved organic carbon concentrations, and aquatic toxicity, associated with winter storm runoff concurrent with winter run Chinook salmon out-migration. Sites were selected that represented the primary habitat of juvenile Chinook salmon and included major tributaries within the Sacramento and San Joaquin River Basins and the Sacramento?San Joaquin Delta. Water samples were collected daily for a period of seven days during two winter storm events in each year. Additional samples were collected weekly during January through April or May in both years. Concentrations of 31 currently used pesticides were measured in filtered water samples using solid-phase extraction and gas chromatography-mass spectrometry at the U.S. Geological Survey's organic chemistry laboratory in Sacramento, California. Dissolved organic carbon concentrations were analyzed in filtered water samples using a Shimadzu TOC-5000A total organic carbon

  12. Demographics and movements of least terns and piping plovers in the Central Platte River Valley, Nebraska

    USGS Publications Warehouse

    Roche, Erin A.; Sherfy, Mark H.; Ring, Megan M.; Shaffer, Terry L.; Anteau, Michael J.; Stucker, Jennifer H.

    2016-08-09

    The Central Platte River Valley provides breeding habitat for a variety of migratory birds, including federally endangered interior least terns (Sternula antillarum; least tern) and threatened piping plovers (Charadrius melodus). Since 2009, researchers have collected demographic data on both species that span their lifecycle (that is, from egg laying through survival of adults). Demographic data were used to estimate vital rates (for example, nest survival, chick survival, and so on) for both species and assess how these vital rates were related to type and age of nesting habitat. Nest survival of both species was unrelated to the age of the site a nest was initiated on. Piping plover chick survival to fledging age was not related to the age of the site it was hatched at, however, the probability of a least tern chick surviving to fledging was higher at older sites. In general there were fewer piping plover nests than least tern nests found at sites created through either the physical construction of a new site or new vegetation management regimes, during 2009–14.Mean daily least tern nest survival was 0.9742 (95-percent confidence interval [CI]: 0.9692–0.9783) and cumulative nest survival was 0.59 (95-percent CI: 0.53–0.65). Mean daily least tern chick survival was 0.9602 (95-percent CI: 0.9515–0.9673) and cumulative survival to fledging was 0.54 (95-percent CI = 0.48–0.61). Annual apparent survival rates were estimated at 0.42 (95-percent CI = 0.22–0.64) for adult least terns nesting in the Central Platte River Valley and an apparent survival rate of 0.14 (95-pecent CI = 0.04–0.41) for juvenile least terns. The number of least tern nests present at sites created during 2009–14 was associated with the age of the site; more least tern nests were associated with older sites. During 2009–14, there were four (less than 1 percent of all chicks marked) least tern chicks hatched from the Central Platte River Valley that were subsequently captured on

  13. Magmatic-Tectonic Interactions: Implications for Seismic Hazard Assessment in the Central Walker Lane and Long Valley Caldera Regions

    NASA Astrophysics Data System (ADS)

    Chacko, R.; Hammond, W. C.; Blewitt, G.; Bormann, J. M.

    2014-12-01

    Accurate estimates of fault slip rates based on geodetic data rely on measurements that represent the long-term deformation of the crust. In the Central Walker Lane/Sierra Nevada transition, the Long Valley Caldera region has experienced multiple episodes of uplift and subsidence during the last four decades. The latest episode began in late 2011 and is detectable as a transient signal in the time series of GPS stations around the caldera. These transient signals become more apparent and reveal the extent of the impact on the ambient crustal deformation field of the Walker Lane when the velocity vectors are transformed to a Sierra-Nevada reference frame. Estimating contemporary slip-rates on faults for the purpose of seismic hazard assessment in the region around Long Valley requires detecting and subtracting the transient signals caused by the uplift and subsidence in the caldera. We estimate the geographic extent to which the ambient crustal deformation field is significantly perturbed by ongoing magmatic activity in Long Valley. We present a time variable 3D deformation field constrained by InSAR and GPS observations, and discuss the implications that tectonic-magmatic interaction have for estimates of present-day fault slip-rate. We model the time dependent deformation at Long Valley by analyzing InSAR time series from Envisat and ERS interferograms spanning a period of more than 19 years. We use an analytical volcano deformation source model derived from vertical (GPS) and line of site (InSAR) component of geodetic observations to estimate the horizontal component of the signals associated with magmatic activity beneath the caldera. Previous studies showed that the latest episode of uplift can be modeled with a Mogi source located at a depth of ~6 km with a volume change of 0.03 km3 beneath the resurgent dome. This model predicts a perturbation to the ambient crustal deformation field extending as far as 60 km from the center of the resurgent dome. Thus the

  14. Sutter Buttes-the lone volcano in California's Great Valley

    USGS Publications Warehouse

    Hausback, Brain P.; Muffler, L.J. Patrick; Clynne, Michael A.

    2011-01-01

    The volcanic spires of the Sutter Buttes tower 2,000 feet above the farms and fields of California's Great Valley, just 50 miles north-northwest of Sacramento and 11 miles northwest of Yuba City. The only volcano within the valley, the Buttes consist of a central core of volcanic domes surrounded by a large apron of fragmental volcanic debris. Eruptions at the Sutter Buttes occurred in early Pleistocene time, 1.6 to 1.4 million years ago. The Sutter Buttes are not part of the Cascade Range of volcanoes to the north, but instead are related to the volcanoes in the Coast Ranges to the west in the vicinity of Clear Lake, Napa Valley, and Sonoma Valley.

  15. A Bayesian approach to infer nitrogen loading rates from crop and land-use types surrounding private wells in the Central Valley, California

    NASA Astrophysics Data System (ADS)

    Ransom, Katherine M.; Bell, Andrew M.; Barber, Quinn E.; Kourakos, George; Harter, Thomas

    2018-05-01

    This study is focused on nitrogen loading from a wide variety of crop and land-use types in the Central Valley, California, USA, an intensively farmed region with high agricultural crop diversity. Nitrogen loading rates for several crop types have been measured based on field-scale experiments, and recent research has calculated nitrogen loading rates for crops throughout the Central Valley based on a mass balance approach. However, research is lacking to infer nitrogen loading rates for the broad diversity of crop and land-use types directly from groundwater nitrate measurements. Relating groundwater nitrate measurements to specific crops must account for the uncertainty about and multiplicity in contributing crops (and other land uses) to individual well measurements, and for the variability of nitrogen loading within farms and from farm to farm for the same crop type. In this study, we developed a Bayesian regression model that allowed us to estimate land-use-specific groundwater nitrogen loading rate probability distributions for 15 crop and land-use groups based on a database of recent nitrate measurements from 2149 private wells in the Central Valley. The water and natural, rice, and alfalfa and pasture groups had the lowest median estimated nitrogen loading rates, each with a median estimate below 5 kg N ha-1 yr-1. Confined animal feeding operations (dairies) and citrus and subtropical crops had the greatest median estimated nitrogen loading rates at approximately 269 and 65 kg N ha-1 yr-1, respectively. In general, our probability-based estimates compare favorably with previous direct measurements and with mass-balance-based estimates of nitrogen loading. Nitrogen mass-balance-based estimates are larger than our groundwater nitrate derived estimates for manured and nonmanured forage, nuts, cotton, tree fruit, and rice crops. These discrepancies are thought to be due to groundwater age mixing, dilution from infiltrating river water, or denitrification

  16. The Imperial Valley of California is critical to wintering Mountain Plovers

    USGS Publications Warehouse

    Wunder, Michael B.; Knopf, F.L.

    2003-01-01

    We surveyed Mountain Plovers (Charadrius montanus) wintering in the Imperial Valley of California in January 2001, and also recorded the types of crop fields used by plovers in this agricultural landscape. We tallied 4037 plovers in 36 flocks ranging in size from 4 to 596 birds. Plovers were more common on alfalfa and Bermudagrass fields than other field types. Further, most birds were on alfalfa fields that were currently being (or had recently been) grazed, primarily by domestic sheep. Plovers used Bermudagrass fields only after harvest and subsequent burning. Examination of Christmas Bird Count data from 1950–2000 indicated that the Mountain Plover has abandoned its historical wintering areas on the coastal plains of California. Numbers in the Central Valley seem to have undergone recent declines also. We believe that the cultivated landscape of the Imperial Valley provides wintering habitats for about half of the global population of Mountain Plovers. We attribute the current importance of the Imperial Valley for Mountain Plovers to loss of native coastal and Central Valley habitats rather than to a behavioral switching of wintering areas through time. Future changes in specific cropping or management practices in the Imperial Valley will have a major impact on the conservation status of this species.

  17. Climatic and morphological controls on post-glacial lake and river valley evolution in the Weichselian belt - an example from the Wda valley, Northern Poland

    NASA Astrophysics Data System (ADS)

    Kramkowski, M. A.; Błaszkiewicz, M.; Piotrowski, J. A.; Brauer, A.; Gierszewski, P.; Kordowski, J.; Lamparski, P.; Lorenz, S.; Noryśkiewicz, A. M.; Ott, F.; Slowinski, M. M.; Tyszkowski, S.

    2014-12-01

    The River Wda valley is a classical example of a polygenetic valley, consisting of former lake basins joined by erosive gap sections. In its middle section, which was the subject of our research, a fragment of an abandoned Lateglacial river valley is preserved, which is unique for the Weichselian moraine belt in the Central European Lowlands. The analysis of the relationship between the lacustrine and fluvial sediments and landforms enabled the authors to report many evolutionary connections between the initial period of the river system formation and the emergence of lakes during the Weichselian Lateglacial. The surface drainage essentially determined the progress of melting of dead ice blocks buried in the glacial depressions, which finally led to lake formation there. Most of the lake basins in the study area were formed during the Bølling-Allerød period. However, one section of the subglacial channel was not exposed to the thermokarst conditions and was therefore preserved with dead ice blocks throughout the entire Lateglacial. The dead ice decay at the beginning of the Holocene, as well as the emergence of another lake, created a lower base level of erosion in the close vicinity of the abandoned valley and induced a change of the river's course. Both fluvial and lacustrine deposits and landforms distributed in the central section of the River Wda valley indicate two processes, which proceeded simultaneously: (1) emergence of fluvially joined lake basins within a glacial channel, (2) degradation of the river bed in the gap sections interfering between the lakes. The processes described for the central section of the River Wda channel indicate a very dynamic river valley development during the Weichselian Lateglacial and the early Holocene. The valley formation was tightly interwoven with the morphogenesis of the primary basins within the valley, mainly with the melting of the buried blocks of dead ice and the development of lakes. This study is a contribution

  18. Effects of the Structure of Water Rights on Agricultural Production During Drought: A Spatiotemporal Analysis of California's Central Valley

    NASA Astrophysics Data System (ADS)

    Nelson, K. S.; Burchfield, E. K.

    2017-10-01

    California's Central Valley region has been called the "bread-basket" of the United States. The region is home to one of the most productive agricultural systems on the planet. Such high levels of agricultural productivity require large amounts of fresh water for irrigation. However, the long-term availability of water required to sustain high levels of agricultural production is being called into question following the latest drought in California. In this paper, we use Bayesian multilevel spatiotemporal modeling techniques to examine the influence of the structure of surface water rights in the Central Valley on agricultural production during the recent drought. California is an important place to study these dynamics as it is the only state to recognize the two dominant approaches to surface water management in the United States: riparian and appropriative rights. In this study, Bayesian spatiotemporal modeling is employed to account for spatial processes that have the potential to influence the effects of water right structures on agricultural production. Results suggest that, after accounting for spatiotemporal dependencies in the data, seniority in surface water access significantly improves crop health and productivity on cultivated lands but does not independently affect the ability to maintain cultivated extent. In addition, agricultural productivity in watersheds with more junior surface water rights shows less sensitivity to cumulative drought exposure than other watersheds, however the extent of cultivation in these same watersheds is relatively more sensitive to cumulative drought exposure.

  19. Airborne Dust Models in Valley Fever Research

    NASA Astrophysics Data System (ADS)

    Sprigg, W. A.; Galgiani, J. N.; Vujadinovic, M.; Pejanovic, G.; Vukovic, A. J.; Prasad, A. K.; Djurdjevic, V.; Nickovic, S.

    2011-12-01

    Dust storms (haboobs) struck Phoenix, Arizona, in 2011 on July 5th and again on July 18th. One potential consequence: an estimated 3,600 new cases of Valley Fever in Maricopa County from the first storm alone. The fungi, Coccidioides immitis, the cause of the respiratory infection, Valley Fever, lives in the dry desert soils of the American southwest and southward through Mexico, Central America and South America. The fungi become part of the dust storm and, a few weeks after inhalation, symptoms of Valley Fever may appear, including pneumonia-like illness, rashes, and severe fatigue. Some fatalities occur. Our airborne dust forecast system predicted the timing and extent of the storm, as it has done with other, often different, dust events. Atmosphere/land surface models can be part of public health services to reduce risk of Valley Fever and exacerbation of other respiratory and cardiovascular illness.

  20. 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.

  1. A statistical learning framework for groundwater nitrate models of the Central Valley, California, USA

    USGS Publications Warehouse

    Nolan, Bernard T.; Fienen, Michael N.; Lorenz, David L.

    2015-01-01

    We used a statistical learning framework to evaluate the ability of three machine-learning methods to predict nitrate concentration in shallow groundwater of the Central Valley, California: boosted regression trees (BRT), artificial neural networks (ANN), and Bayesian networks (BN). Machine learning methods can learn complex patterns in the data but because of overfitting may not generalize well to new data. The statistical learning framework involves cross-validation (CV) training and testing data and a separate hold-out data set for model evaluation, with the goal of optimizing predictive performance by controlling for model overfit. The order of prediction performance according to both CV testing R2 and that for the hold-out data set was BRT > BN > ANN. For each method we identified two models based on CV testing results: that with maximum testing R2 and a version with R2 within one standard error of the maximum (the 1SE model). The former yielded CV training R2 values of 0.94–1.0. Cross-validation testing R2 values indicate predictive performance, and these were 0.22–0.39 for the maximum R2 models and 0.19–0.36 for the 1SE models. Evaluation with hold-out data suggested that the 1SE BRT and ANN models predicted better for an independent data set compared with the maximum R2 versions, which is relevant to extrapolation by mapping. Scatterplots of predicted vs. observed hold-out data obtained for final models helped identify prediction bias, which was fairly pronounced for ANN and BN. Lastly, the models were compared with multiple linear regression (MLR) and a previous random forest regression (RFR) model. Whereas BRT results were comparable to RFR, MLR had low hold-out R2 (0.07) and explained less than half the variation in the training data. Spatial patterns of predictions by the final, 1SE BRT model agreed reasonably well with previously observed patterns of nitrate occurrence in groundwater of the Central Valley.

  2. Registration of 'Hidden Valley' meadow fescue

    USDA-ARS?s Scientific Manuscript database

    'Hidden Valley' (Reg. No. CV-xxxx, PI xxxxxx) meadow fescue [Schedonorus pratensis (Huds.) P. Beauv.; syn. Festuca pratensis Huds.; syn. Lolium pratense (Huds.) Darbysh.] is a synthetic population originating from 561 parental genotypes. The original germplasm is of unknown central or northern Europ...

  3. Starch grain and phytolith evidence for early ninth millennium B.P. maize from the Central Balsas River Valley, Mexico

    PubMed Central

    Piperno, Dolores R.; Ranere, Anthony J.; Holst, Irene; Iriarte, Jose; Dickau, Ruth

    2009-01-01

    Questions that still surround the origin and early dispersals of maize (Zea mays L.) result in large part from the absence of information on its early history from the Balsas River Valley of tropical southwestern Mexico, where its wild ancestor is native. We report starch grain and phytolith data from the Xihuatoxtla shelter, located in the Central Balsas Valley, that indicate that maize was present by 8,700 calendrical years ago (cal. B.P.). Phytolith data also indicate an early preceramic presence of a domesticated species of squash, possibly Cucurbita argyrosperma. The starch and phytolith data also allow an evaluation of current hypotheses about how early maize was used, and provide evidence as to the tempo and timing of human selection pressure on 2 major domestication genes in Zea and Cucurbita. Our data confirm an early Holocene chronology for maize domestication that has been previously indicated by archaeological and paleoecological phytolith, starch grain, and pollen data from south of Mexico, and reshift the focus back to an origin in the seasonal tropical forest rather than in the semiarid highlands. PMID:19307570

  4. Pliocene and Pleistocene geologic and climatic evolution in the San Luis Valley of south-central Colorado

    USGS Publications Warehouse

    Rogers, K.L.; Larson, E.E.; Smith, G.; Katzman, D.; Smith, G.R.; Cerling, T.; Wang, Y.; Baker, R.G.; Lohmann, K.C.; Repenning, C.A.; Patterson, P.; Mackie, G.

    1992-01-01

    Sediments of the Alamosa Formation spanning the upper part of the Gauss and most of the Matuyama Chrons were recovered by coring in the high (2300 m) San Luis Valley of south-central Colorado. The study site is located at the northern end of the Rio Grande rift. Lithologic changes in the core sediments provide evidence of events leading to integration of the San Luis drainage basin into the Rio Grande. The section, which includes the Huckleberry Ridge Ash (2.02 Ma) and spans the entire Matuyama Chron, contains pollen, and invertebrate and vertebrate fossils. Stable isotope analyses of inorganic and biogenic carbonate taken over most of the core indicate substantially warmer temperatures than occur today in the San Luis Valley. At the end of the Olduvai Subchron, summer precipitation decreased, summer pan evaporation increased, and temperatures increased slightly compared to the earlier climate represented in the core. By the end of the Jaramillo Subchron, however, cold/wet and warm/dry cycles become evident and continue into the cold/wet regime associated with the deep-sea oxygen-isotope Stage 22 glaciation previously determined from outcrops at the same locality. Correspondence between the Hansen Bluff climatic record and the deep-sea oxygen-isotope record (oxygen-isotope stages from about 110-18) is apparent, indicating that climate at Hansen Bluff was responding to global climatic changes. ?? 1992.

  5. Vivid valleys, pallid peaks? Hypsometric variations and rural-urban land change in the Central Peruvian Andes.

    PubMed

    Haller, Andreas

    2012-11-01

    What happens to the land cover within the hinterland's altitudinal belts while Central Andean cities are undergoing globalization and urban restructuring? What conclusions can be drawn about changes in human land use? By incorporating a regional altitudinal zonation model, direct field observations and GIS analyses of remotely sensed long term data, the present study examines these questions using the example of Huancayo Metropolitano - an emerging Peruvian mountain city of 420,000 inhabitants, situated at 3260 m asl in the Mantaro Valley. The study's results indicate that rapid urban growth during the late 1980s and early 1990s was followed by the agricultural intensification and peri-urban condominization at the valley floor ( quechua ) - since the beginning of Peru's neoliberal era. Moreover, regarding the adjoining steep slopes ( suni ) and subsequent grassland ecosystems ( puna ), the research output presents land cover change trajectories that clearly show an expansion of human land use, such as reforestation for wood production and range burning for livestock grazing, even at high altitudes - despite rural-urban migration trends and contrary to several results of extra-Andean studies. Consequently, rural-urban planners and policy makers are challenged to focus on the manifold impacts of globalization on human land use - at all altitudinal belts of the Andean city's hinterland: toward sustainable mountain development that bridges the social and physical gaps - from the bottom up.

  6. Methods, quality assurance, and data for assessing atmospheric deposition of pesticides in the Central Valley of California

    USGS Publications Warehouse

    Zamora, Celia; Majewski, Michael S.; Foreman, William T.

    2013-01-01

    The U.S. Geological Survey monitored atmospheric deposition of pesticides in the Central Valley of California during two studies in 2001 and 2002–04. The 2001 study sampled wet deposition (rain) and storm-drain runoff in the Modesto, California, area during the orchard dormant-spray season to examine the contribution of pesticide concentrations to storm runoff from rainfall. In the 2002–04 study, the number and extent of collection sites in the Central Valley were increased to determine the areal distribution of organophosphate insecticides and other pesticides, and also five more sample types were collected. These were dry deposition, bulk deposition, and three sample types collected from a soil box: aqueous phase in runoff, suspended sediment in runoff, and surficial-soil samples. This report provides concentration data and describes methods and quality assurance of sample collection and laboratory analysis for pesticide compounds in all samples collected from 16 sites. Each sample was analyzed for 41 currently used pesticides and 23 pesticide degradates, including oxygen analogs (oxons) of 9 organophosphate insecticides. Analytical results are presented by sample type and study period. The median concentrations of both chloryprifos and diazinon sampled at four urban (0.067 micrograms per liter [μg/L] and 0.515 μg/L, respectively) and four agricultural sites (0.079 μg/L and 0.583 μg/L, respectively) during a January 2001 storm event in and around Modesto, Calif., were nearly identical, indicating that the overall atmospheric burden in the region appeared to be fairly similar during the sampling event. Comparisons of median concentrations in the rainfall to those in the McHenry storm-drain runoff showed that, for some compounds, rainfall contributed a substantial percentage of the concentration in the runoff; for other compounds, the concentrations in rainfall were much greater than in the runoff. For example, diazinon concentrations in rainfall were about

  7. Groundwater Age in Multi-Level Water Quality Monitor Wells on California Central Valley Dairies

    NASA Astrophysics Data System (ADS)

    Esser, B. K.; Visser, A.; Hillegonds, D. J.; Singleton, M. J.; Moran, J. E.; Harter, T.

    2011-12-01

    Dairy farming in California's Central Valley is a significant source of nitrate to underlying aquifers. One approach to mitigation is to implement farm-scale management plans that reduce nutrient loading to groundwater while sustaining crop yield. While the effect of different management practices on crop yield is easily measured, their effect on groundwater quality has only infrequently been evaluated. Documenting and predicting the impact of management on water quality requires a quantitative assessment of transport (including timescale and mixing) through the vadose and saturated zones. In this study, we measured tritium, helium isotopic composition, and noble gas concentrations in groundwater drawn from monitor wells on several dairies in the Lower San Joaquin Valley and Tulare Lake Basin of California's Central Valley in order to predict the timescales on which changes in management may produce observable changes in groundwater quality. These dairies differ in age (from <10 to >100 years old), thickness of the vadose zone (from <10 to 60 m), hydrogeologic setting, and primary source of irrigation water (surface or groundwater). All of the dairies use manure wastewater for irrigation and fertilization. Three of the dairies have implemented management changes designed to reduce nutrient loading and/or water usage. Monitor wells in the southern Tulare Lake Basin dairies were installed by UC-Davis as multi-level nested wells allowing depth profiling of tritium and noble gases at these sites. Tritium/helium-3 groundwater ages, calculated using a simple piston-flow model, range from <2 to >50 years. Initial tritium (the sum of measured tritium and tritiogenic helium-3) is close to or slightly above precipitation in the calculated recharge year for young samples; and significantly above the precipitation curve for older samples. This pattern is consistent with the use of 20-30 year old groundwater recharged before 1980 for irrigation, and illustrates how irrigation

  8. Implementation of warm-cloud processes in a source-oriented WRF/Chem model to study the effect of aerosol mixing state on fog formation in the Central Valley of California

    NASA Astrophysics Data System (ADS)

    Lee, H.-H.; Chen, S.-H.; Kleeman, M. J.; Zhang, H.; DeNero, S. P.; Joe, D. K.

    2015-11-01

    The source-oriented Weather Research and Forecasting chemistry model (SOWC) was modified to include warm cloud processes and applied to investigate how aerosol mixing states influence fog formation and optical properties in the atmosphere. SOWC tracks a 6-dimensional chemical variable (X, Z, Y, Size Bins, Source Types, Species) through an explicit simulation of atmospheric chemistry and physics. A source-oriented cloud condensation nuclei module was implemented into the SOWC model to simulate warm clouds using the modified two-moment Purdue Lin microphysics scheme. The Goddard shortwave and longwave radiation schemes were modified to interact with source-oriented aerosols and cloud droplets so that aerosol direct and indirect effects could be studied. The enhanced SOWC model was applied to study a fog event that occurred on 17 January 2011, in the Central Valley of California. Tule fog occurred because an atmospheric river effectively advected high moisture into the Central Valley and nighttime drainage flow brought cold air from mountains into the valley. The SOWC model produced reasonable liquid water path, spatial distribution and duration of fog events. The inclusion of aerosol-radiation interaction only slightly modified simulation results since cloud optical thickness dominated the radiation budget in fog events. The source-oriented mixture representation of particles reduced cloud droplet number relative to the internal mixture approach that artificially coats hydrophobic particles with hygroscopic components. The fraction of aerosols activating into CCN at a supersaturation of 0.5 % in the Central Valley decreased from 94 % in the internal mixture model to 80 % in the source-oriented model. This increased surface energy flux by 3-5 W m-2 and surface temperature by as much as 0.25 K in the daytime.

  9. Implementation of warm-cloud processes in a source-oriented WRF/Chem model to study the effect of aerosol mixing state on fog formation in the Central Valley of California

    NASA Astrophysics Data System (ADS)

    Lee, Hsiang-He; Chen, Shu-Hua; Kleeman, Michael J.; Zhang, Hongliang; DeNero, Steven P.; Joe, David K.

    2016-07-01

    The source-oriented Weather Research and Forecasting chemistry model (SOWC) was modified to include warm cloud processes and was applied to investigate how aerosol mixing states influence fog formation and optical properties in the atmosphere. SOWC tracks a 6-D chemical variable (X, Z, Y, size bins, source types, species) through an explicit simulation of atmospheric chemistry and physics. A source-oriented cloud condensation nuclei module was implemented into the SOWC model to simulate warm clouds using the modified two-moment Purdue Lin microphysics scheme. The Goddard shortwave and long-wave radiation schemes were modified to interact with source-oriented aerosols and cloud droplets so that aerosol direct and indirect effects could be studied. The enhanced SOWC model was applied to study a fog event that occurred on 17 January 2011, in the Central Valley of California. Tule fog occurred because an atmospheric river effectively advected high moisture into the Central Valley and nighttime drainage flow brought cold air from mountains into the valley. The SOWC model produced reasonable liquid water path, spatial distribution and duration of fog events. The inclusion of aerosol-radiation interaction only slightly modified simulation results since cloud optical thickness dominated the radiation budget in fog events. The source-oriented mixture representation of particles reduced cloud droplet number relative to the internal mixture approach that artificially coats hydrophobic particles with hygroscopic components. The fraction of aerosols activating into cloud condensation nuclei (CCN) at a supersaturation of 0.5 % in the Central Valley decreased from 94 % in the internal mixture model to 80 % in the source-oriented model. This increased surface energy flux by 3-5 W m-2 and surface temperature by as much as 0.25 K in the daytime.

  10. Modeling waterfowl habitat selection in the Central Valley of California to better understand the spatial relationship between commercial poultry and waterfowl

    USGS Publications Warehouse

    Matchett, Elliott L.; Casazza, Michael L.; Fleskes, Joseph; Kelman, T.; Cadena, M.; Pitesky, M.

    2017-01-01

    Wildlife researchers frequently study resource and habitat selection of wildlife to understand their potential habitat requirements and to conserve their populations. Understanding wildlife spatial-temporal distributions related to habitat have other applications such as to model interfaces between wildlife and domestic food animals in order to mitigate disease transmission to food animals. The highly pathogenic avian influenza (HPAI) virus represents a significant risk to the poultry industry. The Central Valley of California offers a unique geographical confluence of commercial poultry and wild waterfowl, which are thought to be a key reservoir of avian influenza (AI). Therefore, understanding spatio-temporal distributions of waterfowl could improve our understanding of potential risk of HPAI exposure from a commercial poultry perspective. Using existing radio-telemetry data on waterfowl (U.S. Geological Survey) in combination with habitat and vegetation data based on Geographic Information Systems (GIS), we are developing GIS-based statistical models that predict the probability of waterfowl presence (Habitat Suitability Mapping). Near-real-time application can be developed using recent habitat data derived from Landsat imagery (acquired by satellites and publically available through the U.S. Geological Survey) to predict temporally- and spatially-varying distributions of waterfowl in the Central Valley. These results could be used to provide decision support for the poultry industry in addressing potential risk of HPAI exposure related to waterfowl proximity.

  11. Death Valley California as seen from STS-59

    NASA Image and Video Library

    1994-04-13

    STS059-86-059 (9-20 April 1994) --- This oblique handheld Hasselblad 70mm photo shows Death Valley, near California's border with Nevada. The valley -- the central feature of Death Valley National Monument -- extends north to south for some 140 miles (225 kilometers). Hemmed in to the east by the Amargosa Range and to the west by the Panamints, its width varies from 5 to 15 miles (8 to 24 kilometers). Using Spaceborne Imaging Radar (SIR-C) and X-band Synthetic Aperture Radar (X-SAR) onboard the Space Shuttle Endeavour, the crew was able to record a great deal of data on this and other sites, as part of NASA's Mission to Planet Earth.

  12. Ground-water resources investigation in the Amran Valley, Yeman Arab Republic

    USGS Publications Warehouse

    Tibbitts, G. Chase; Aubel, James

    1980-01-01

    A program of hydrologic studies and exploratory drilling was conducted intermittently between 1974 and 1978 to evaluate the water-bearing properties of the unconsolidated alluvial sediments and associated rocks in the semi-arid Amran Valley basin, an 800-square-kilometer area in north-central Yemen Arab Republic. Inventory data from 395 wells were compiled, observation well and rain-gage networks were established and 16 standard complete chemical analyses were made for samples from selected wells. The water resources of the area were overexploited. The chemical quality of the water is generally good. Four aquifer tests were run to determine transmissivity and storage characteristics. The pumping tests show that groundwater occurs under semi-confined leaky-aquifer conditions in the valley fill. Wells drilled in the alluvial fill of the south-central part of the valley have the highest yields. Wells penetrating the limestone and volcanic rocks generally have little or no yield except in fracture zones. Basalt flows occur interbedded with the wadi alluvium at several depths. Cropping out rocks in the Amran Valley range in age from late Jurassic to Holocene. (USGS)

  13. Geohydrology of the Unconsolidated Valley-Fill Aquifer in the Meads Creek Valley, Schuyler and Steuben Counties, New York

    USGS Publications Warehouse

    Miller, Todd S.; Bugliosi, Edward F.; Reddy, James E.

    2008-01-01

    The Meads Creek valley encompasses 70 square miles of predominantly forested uplands in the upper Susquehanna River drainage basin. The valley, which was listed as a Priority Waterbody by the New York State Department of Environmental Conservation in 2004, is prone to periodic flooding, mostly in its downstream end, where development is occurring most rapidly. Hydraulic characteristics of the unconsolidated valley-fill aquifer were evaluated, and seepage rates in losing and gaining tributaries were calculated or estimated, in an effort to delineate the aquifer geometry and identify the factors that contribute to flooding. Results indicated that (1) Meads Creek gained about 61 cubic feet of flow per second (about 6.0 cubic feet per second per mile of stream channel) from ground-water discharge and inflow from tributaries in its 10.2-mile reach between the northernmost and southernmost measurement sites; (2) major tributaries in the northern part of the valley are not significant sources of recharge to the aquifer; and (3) major tributaries in the central and southern part of the valley provide recharge to the aquifer. The ground-water portion of streamflow in Meads Creek (excluding tributary inflow) was 11.3 cubic feet per second (ft3/s) in the central part of the valley and 17.2 ft3/s in the southern part - a total of 28.5 ft3/s. Ground-water levels were measured in 29 wells finished in unconfined deposits for construction of a potentiometric-surface map to depict directions of ground-water flow within the valley. In general, ground water flows from the edges of the valley toward Meads Creek and ultimately discharges to it. The horizontal hydraulic gradient for the entire 12-mile-long aquifer averages about 30 feet per mile, whereas the gradient in the southern fourth of the valley averages about half that - about 17 feet per mile. A water budget for the aquifer indicated that 28 percent of recharge was derived from precipitation that falls on the aquifer, 32

  14. Analysis of the quality of image data acquired by the LANDSAT-4 thematic mapper and multispectral scanners. [Central Valley, California

    NASA Technical Reports Server (NTRS)

    Colwell, R. N. (Principal Investigator)

    1983-01-01

    Image products and numeric data were extracted from both TM and MSS data in an effort to evaluate the quality of these data for interpreting major agricultural resources and conditions in California's Central Valley. The utility of TM data appears excellent for meeting most of the inventory objectives of the agricultural resource specialist. These data should be extremely valuable for crop type and area proportion estimation, for updating agricultural land use survey maps at 1:24,000-scale and smaller, for field boundary definition, and for determining the size and location of individual farmsteads.

  15. Aeromagnetic survey map of Sacramento Valley, California

    USGS Publications Warehouse

    Langenheim, Victoria E.

    2015-01-01

    Three aeromagnetic surveys were flown to improve understanding of the geology and structure in the Sacramento Valley. The resulting data serve as a basis for geophysical interpretations, and support geological mapping, water and mineral resource investigations, and other topical studies. Local spatial variations in the Earth's magnetic field (evident as anomalies on aeromagnetic maps) reflect the distribution of magnetic minerals, primarily magnetite, in the underlying rocks. In many cases the volume content of magnetic minerals can be related to rock type, and abrupt spatial changes in the amount of magnetic minerals commonly mark lithologic or structural boundaries. Bodies of serpentinite and other mafic and ultramafic rocks tend to produce the most intense positive magnetic anomalies (for example, in the northwest part of the map). These rock types are the inferred sources, concealed beneath weakly magnetic, valley-fill deposits, of the most prominent magnetic features in the map area, the magnetic highs that extend along the valley axis. Cenozoic volcanic rocks are also an important source of magnetic anomalies and coincide with short-wavelength anomalies that can be either positive (strong central positive anomaly flanked by lower-amplitude negative anomalies) or negative (strong central negative anomaly flanked by lower-amplitude positive anomalies), reflecting the contribution of remanent magnetization. Rocks with more felsic compositions or even some sedimentary units also can cause measurable magnetic anomalies. For example, the long, linear, narrow north-trending anomalies (with amplitudes of <50 nanoteslas [nT]) along the western margin of the valley coincide with exposures of the Mesozoic Great Valley sequence. Note that isolated, short-wavelength anomalies, such as those in the city of Sacramento and along some of the major roads, are caused by manmade features.

  16. Legacy lead arsenate soil contamination at childcare centers in the Yakima Valley, Central Washington, USA.

    PubMed

    Durkee, Jenna; Bartrem, Casey; Möller, Gregory

    2017-02-01

    From the early 1900s to the 1950s, Yakima Valley orchards were commonly treated with lead arsenate (LA) insecticides. Lead (Pb) and arsenic (As) soil contamination has been identified on former orchard lands throughout Central Washington and pose a threat to human health and the environment. The levels of Pb and As in soil and interior dust at participating childcare centers in the Upper Yakima Valley (Yakima County), Washington were sampled to explore exposure potential for young children. Childcare center soils were collected from two soil depths, homogenized, and analyzed in bulk by a field-portable X-ray fluorescence spectrometer (XRF). Interior dust wipes samples were collected from at least two locations in each facility. All soil samples >250 mg/kg Pb and/or >20 As mg/kg were sieved to 250 μm, tested by XRF a second time, and analyzed via acid digestion and inductively coupled plasma mass spectrometry (ICP-MS) analysis. Bulk and sieved XRF results, as well as ICP-MS to XRF results were strongly correlated. Maximum Pb and As XRF results indicated that 4 (21%) and 8 (42%) of the 19 childcare centers surveyed exceeded the regulatory standard for Pb and As, respectively. Historic land use was significantly associated with elevated Pb and As levels. Interior dust loadings were below United States Environmental Protection Agency (EPA) guidelines. Childcare centers are areas of intensive use for children and when coupled with potential residential exposure in their homes, the total daily exposure is a potential hazard to children. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Evolution of Late Miocene to Contemporary Displacement Transfer Between the Northern Furnace Creek and Southern Fish Lake Valley Fault Zones and the Central Walker Lane, Western Great Basin, Nevada

    NASA Astrophysics Data System (ADS)

    Oldow, J. S.; Geissman, J. W.

    2013-12-01

    Late Miocene to contemporary displacement transfer from the north Furnace Creek (FCF) and southern Fish Lake Valley (FLVF) faults to structures in the central Walker Lane was and continues to be accommodated by a belt of WNW-striking left-oblique fault zones in the northern part of the southern Walker Lane. The WNW fault zones are 2-9 km wide belts of anastomosing fault strands that intersect the NNW-striking FCF and southern FLVF in northern Death Valley and southern Fish Lake Valley, respectively. The WNW fault zones extend east for over 60 km where they merge with a 5-10 km wide belt of N10W striking faults that marks the eastern boundary of the southern Walker Lane. Left-oblique displacement on WNW faults progressively decreases to the east, as motion is successively transferred northeast on NNE-striking faults. NNE faults localize and internally deform extensional basins that each record cumulative net vertical displacements of between 3.0 and 5.2 km. The transcurrent faults and associated basins decrease in age from south to north. In the south, the WNW Sylvania Mountain fault system initiated left-oblique motion after 7 Ma but does not have evidence of contemporary displacement. Farther north, the left-oblique motion on the Palmetto Mountain fault system initiated after 6.0 to 4.0 Ma and has well-developed scarps in Quaternary deposits. Cumulative left-lateral displacement for the Sylvania Mountain fault system is 10-15 km, and is 8-12 km for the Palmetto fault system. The NNE-striking faults that emanate from the left-oblique faults merge with NNW transcurrent faults farther north in the eastern part of the Mina deflection, which links the Owens Valley fault of eastern California to the central Walker Lane. Left-oblique displacement on the Sylvania Mountain and Palmetto Mountain fault zones deformed the Furnace Creek and Fish Lake Valley faults. Left-oblique motion on Sylvania Mountain fault deflected the FCF into the 15 km wide Cucomungo Canyon restraining

  18. Conservation Effects Assessment Project-Wetlands assessment in California's Central Valley and Upper Klamath River Basin

    USGS Publications Warehouse

    Duffy, Walter G.; Kahara, Sharon N.; Records, Rosemary M.

    2011-01-01

    Executive Summary-Ecosystem Services Derived from Wetlands Reserve Program Conservation Practices in California's Central Valley and Oregon's Upper Klamath River Basin. The Wetlands Reserve Program (WRP) is one of several programs implemented by the U.S. Department of Agriculture (USDA). Since the WRP's inception in 1990, it has resulted in the restoration of approximately 29,000 hectares in California's Central Valley (CCV) and roughly 12,300 hectares in Oregon's Upper Klamath River Basin (UKRB). Both the CCV and UKRB are agricultural dominated landscapes that have experienced extensive wetland losses and hydrological alteration. Restored habitats in the CCV and UKRB are thought to provide a variety of ecosystem services, but little is known about the actual benefits afforded. The U.S. Geological Survey (USGS) California Cooperative Fish and Wildlife Unit in collaboration with the USDA Natural Resources Conservation Service surveyed 70 WRP sites and 12 National Wildlife Refuge sites in the CCV, and 11 sites in the UKRB to estimate ecosystem services provided. In the CCV, sites were selected along three primary gradients; (1) restoration age, (2) management intensity, and (3) latitude (climate). Sites in the UKRB were assessed along restoration age and management intensity gradients where possible. The management intensity gradient included information about the type and frequency of conservation practices applied at each site, which was then ranked into three categories that differentiated sites primarily along a hydrological gradient. Information collected was used to estimate the following ecosystem services: Soil and vegetation nutrient content, soil loss reduction, floodwater storage as well as avian, amphibian, fish, and pollinator use and habitat availability. Prior to this study, very little was known about WRP habitat morphology in the CCV and UKRB. Therefore in this study, we described these habitats and related them to ecosystem services provided. Our

  19. Vivid valleys, pallid peaks? Hypsometric variations and rural–urban land change in the Central Peruvian Andes

    PubMed Central

    Haller, Andreas

    2012-01-01

    What happens to the land cover within the hinterland's altitudinal belts while Central Andean cities are undergoing globalization and urban restructuring? What conclusions can be drawn about changes in human land use? By incorporating a regional altitudinal zonation model, direct field observations and GIS analyses of remotely sensed long term data, the present study examines these questions using the example of Huancayo Metropolitano – an emerging Peruvian mountain city of 420,000 inhabitants, situated at 3260 m asl in the Mantaro Valley. The study's results indicate that rapid urban growth during the late 1980s and early 1990s was followed by the agricultural intensification and peri-urban condominization at the valley floor (quechua) – since the beginning of Peru's neoliberal era. Moreover, regarding the adjoining steep slopes (suni) and subsequent grassland ecosystems (puna), the research output presents land cover change trajectories that clearly show an expansion of human land use, such as reforestation for wood production and range burning for livestock grazing, even at high altitudes – despite rural–urban migration trends and contrary to several results of extra-Andean studies. Consequently, rural–urban planners and policy makers are challenged to focus on the manifold impacts of globalization on human land use – at all altitudinal belts of the Andean city's hinterland: toward sustainable mountain development that bridges the social and physical gaps – from the bottom up. PMID:23564987

  20. Linking groundwater use and stress to specific crops using the groundwater footprint in the Central Valley and High Plains aquifer systems, U.S.

    NASA Astrophysics Data System (ADS)

    Esnault, Laurent; Gleeson, Tom; Wada, Yoshihide; Heinke, Jens; Gerten, Dieter; Flanary, Elizabeth; Bierkens, Marc F. P.; van Beek, Ludovicus P. H.

    2014-06-01

    A number of aquifers worldwide are being depleted, mainly by agricultural activities, yet groundwater stress has not been explicitly linked to specific agricultural crops. Using the newly developed concept of the groundwater footprint (the area required to sustain groundwater use and groundwater-dependent ecosystem services), we develop a methodology to derive crop-specific groundwater footprints. We illustrate this method by calculating high-resolution groundwater footprint estimates of crops in two heavily used aquifer systems: the Central Valley and High Plains, U.S. In both aquifer systems, hay and haylage, corn, and cotton have the largest groundwater footprints, which highlights that most of the groundwater stress is induced by crops meant for cattle feed. Our results are coherent with other studies in the High Plains but suggest lower groundwater stress in the Central Valley, likely due to artificial recharge from surface water diversions which were not taken into account in previous estimates. Uncertainties of recharge and irrigation application efficiency contribute the most to the total relative uncertainty of the groundwater footprint to aquifer area ratios. Our results and methodology will be useful for hydrologists, water resource managers, and policy makers concerned with which crops are causing the well-documented groundwater stress in semiarid to arid agricultural regions around the world.

  1. Linking Groundwater Use and Stress to Specific Crops Using the Groundwater Footprint in the Central Valley and High Plains Aquifer Systems, U.S.

    NASA Astrophysics Data System (ADS)

    Wada, Y.; Esnault, L.; Gleeson, T.; Heinke, J.; Gerten, D.; Flanary, E.; Bierkens, M. F.; Van Beek, L. P.

    2014-12-01

    A number of aquifers worldwide are being depleted, mainly by agricultural activities, yet groundwater stress has not been explicitly linked to specific agricultural crops. Using the newly-developed concept of the groundwater footprint (the area required to sustain groundwater use and groundwater-dependent ecosystem services), we develop a methodology to derive crop-specific groundwater footprints. We illustrate this method by calculating high resolution groundwater footprint estimates of crops in two heavily used aquifer systems: the Central Valley and High Plains, U.S. In both aquifer systems, hay and haylage, corn and cotton have the largest groundwater footprints, which highlights that most of the groundwater stress is induced by crops meant for cattle feed. Our results are coherent with other studies in the High Plains but suggest lower groundwater stress in the Central Valley, likely due to artificial recharge from surface water diversions which were not taken into account in previous estimates. Uncertainties of recharge and irrigation application efficiency contribute the most to the total relative uncertainty of the groundwater footprint to aquifer area ratios. Our results and methodology will be useful for hydrologists, water resource managers, and policy makers concerned with which crops are causing the well-documented groundwater stress in semiarid to arid agricultural regions around the world.

  2. Ground-water hydrology of the upper Sevier River Basin, south-central Utah, and simulation of ground-water flow in the valley-fill in Panguitch Valley.

    USGS Publications Warehouse

    Thiros, Susan A.; Brothers, William C.

    1993-01-01

    The ground-water hydrology of the upper Sevier River basin, primarily of the unconsolidated valley-fill aquifers, was studied from 1988 to 1989. Recharge to the valley-fill aquifers is mostly by seepage from surface-water sources. Changes in soil-moisture content am water levels were measured in Panguitch Valley both at a flood-irrigated and at a sprinkler-irrigated alfalfa field to quantify seepage from unconsumed irrigation water. Lag time between irrigation and water-level response decreased from 6 to 2 days in the flood-irrigated field as the soil-moisture content increased. Water levels measured in the sprinkler-irrigated field did not respond to irrigation. Discharge from the valley-fill aquifer to the Sevier River in Panguitch Valley is about 53,570 acre-feet per year.Water levels measured in wells from 1951 to 1989 tend to fluctuate with the quantity of precipitation falling at higher elevations. Ground-water discharge to the Sevier River in Panguitch Valley causes a general increase in the specific conductance of the river in a downstream direction.A three-layered ground-water-flow model was used to simulate the effects of changes in irrigation practices am increased ground-water withdrawals in Panguitch Valley. The establishment of initial conditions consisted of comparing simulated water levels and simulated gains and losses from the Sevier River and selected canals with values measured during the 1988 irrigation season. The model was calibrated by comparing water-level changes measured from 1961 to 1963 to simulated changes. A simulated change from flood to sprinkler irrigation resulted in a maximum decline in water level of 0.9 feet after the first year of change. Simulating additional discharge from wells resulted in drawdowns of about 20 feet after the first year of pumping.

  3. A hybrid machine learning model to predict and visualize nitrate concentration throughout the Central Valley aquifer, California, USA

    USGS Publications Warehouse

    Ransom, Katherine M.; Nolan, Bernard T.; Traum, Jonathan A.; Faunt, Claudia; Bell, Andrew M.; Gronberg, Jo Ann M.; Wheeler, David C.; Zamora, Celia; Jurgens, Bryant; Schwarz, Gregory E.; Belitz, Kenneth; Eberts, Sandra; Kourakos, George; Harter, Thomas

    2017-01-01

    Intense demand for water in the Central Valley of California and related increases in groundwater nitrate concentration threaten the sustainability of the groundwater resource. To assess contamination risk in the region, we developed a hybrid, non-linear, machine learning model within a statistical learning framework to predict nitrate contamination of groundwater to depths of approximately 500 m below ground surface. A database of 145 predictor variables representing well characteristics, historical and current field and landscape-scale nitrogen mass balances, historical and current land use, oxidation/reduction conditions, groundwater flow, climate, soil characteristics, depth to groundwater, and groundwater age were assigned to over 6000 private supply and public supply wells measured previously for nitrate and located throughout the study area. The boosted regression tree (BRT) method was used to screen and rank variables to predict nitrate concentration at the depths of domestic and public well supplies. The novel approach included as predictor variables outputs from existing physically based models of the Central Valley. The top five most important predictor variables included two oxidation/reduction variables (probability of manganese concentration to exceed 50 ppb and probability of dissolved oxygen concentration to be below 0.5 ppm), field-scale adjusted unsaturated zone nitrogen input for the 1975 time period, average difference between precipitation and evapotranspiration during the years 1971–2000, and 1992 total landscape nitrogen input. Twenty-five variables were selected for the final model for log-transformed nitrate. In general, increasing probability of anoxic conditions and increasing precipitation relative to potential evapotranspiration had a corresponding decrease in nitrate concentration predictions. Conversely, increasing 1975 unsaturated zone nitrogen leaching flux and 1992 total landscape nitrogen input had an increasing relative

  4. Partitioning Evapotranspiration over a Vineyard in California's Central Valley

    NASA Astrophysics Data System (ADS)

    Alfieri, J. G.; Kustas, W. P.; Prueger, J. H.; Agam, N.

    2016-12-01

    The increasing demand for limited water resources due to the ongoing California drought hampers crop production and damages the state's economy. In order to ameliorate the negative consequences of drought and ensure the sustainability of California agriculture, policymakers, resource managers, and agricultural producers must maximize the effective use of the available water. In turn, achieving this goal is predicated on accurate information regarding crop water productivity, the fraction of the total evapotranspiration (ET) that contributes to crop yield expressed in terms of transpiration. However, while a number of approaches, such as isotope analysis and microlysimeter systems, have been developed to partition ET between soil evaporation (E) and transpiration (T), these approaches can be both costly and labor-intensive. Collecting reliable continuous measurements at field scales remains problematic. This study presents the application of a recently developed correlation-based technique that overcomes these difficulties by leveraging high frequency data measured via eddy covariance. Specifically, this scheme combines wavelet decomposition and the theoretical relationship between stomatal and non-stomatal moisture and carbon fluxes to separate E and T. The technique was evaluated over a drip-irrigated vineyard located in California's Central Valley using data collected during the 2015 growing season as a part of the GRAPEX (Grape Remote sensing and Atmospheric Profile Experiment) field campaign. The results indicate a clear diurnal pattern in the fraction of ET due to T with a mid-day peak averaging 80% during the growing season. Similarly, there is a strong seasonal trend with the fraction of ET due T increasing in proportion to the increasing vine biomass during the growing season; at its maximum T accounts for approximately 90% of the total moisture flux. These results are in agreement with those from microlysimeter and sapflow measurements collected at the

  5. 78 FR 63491 - Central Valley Project Improvement Act, Water Management Plans

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-24

    ... Valley Project Improvement Act, Water Management Plans AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of availability. SUMMARY: The following Water Management Plans are available for review: Westside... project contractors using best available cost-effective technology and best management practices.'' These...

  6. Pattern of ground deformation in Kathmandu valley during 2015 Gorkha Earthquake, central Nepal

    NASA Astrophysics Data System (ADS)

    Ghimire, S.; Dwivedi, S. K.; Acharya, K. K.

    2016-12-01

    The 25th April 2015 Gorkha Earthquake (Mw=7.8) epicentered at Barpak along with thousands of aftershocks released seismic moment nearly equivalent to an 8.0 Magnitude earthquake rupturing a 150km long fault segment. Although Kathmandu valley was supposed to be severely devastated by such major earthquake, post earthquake scenario is completely different. The observed destruction is far less than anticipated as well as the spatial pattern is different than expected. This work focuses on the behavior of Kathmandu valley sediments during the strong shaking by the 2015 Gorkha Earthquake. For this purpose spatial pattern of destruction is analyzed at heavily destructed sites. To understand characteristics of subsurface soil 2D-MASW survey was carried out using a 24-channel seismograph system. An accellerogram recorded by Nepal Seismological Center was analyzed to characterize the strong ground motion. The Kathmandu valley comprises fluvio-lacustrine deposit with gravel, sand, silt and clay along with few exposures of basement rocks within the sediments. The observations show systematic repetition of destruction at an average interval of 2.5km mostly in sand, silt and clay dominated formations. Results of 2D-MASW show the sites of destruction are characterized by static deformation of soil (liquefaction and southerly dipping cracks). Spectral analysis of the accelerogram indicates maximum power associated with frequency of 1.0Hz. The result of this study explains the observed spatial pattern of destruction in Kathmandu valley. This is correlated with the seismic energy associated with the frequency of 1Hz, which generates an average wavelength of 2.5km with an average S-wave velocity of 2.5km/s. The cumulative effect of dominant frequency and associated wavelength resulted in static deformation of surface soil layers at an average interval of 2.5km. This phenomenon clearly describes the reason for different scenario than that was anticipated in Kathmandu valley.

  7. Winter Storm Continues Across Central U.S.

    NASA Image and Video Library

    2013-12-06

    The powerful winter storm that has been affecting much of the central and western U.S. continues to intensify as it moves into Canada. Snow is tapering off across the Upper Midwest, but heavy snow is possible on Thursday from the Ohio Valley to the mid-Mississippi Valley, with heavy rain possible from the central Appalachians to the lower Mississippi Valley. Freezing rain is possible from Texas to the Ohio Valley. This image was taken by GOES East at 1745Z on December 5, 2013. Credit: NOAA/NASA GOES Project Caption: NOAA NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  8. Data for ground-water test hole near Zamora, Central Valley Aquifer Project, California

    USGS Publications Warehouse

    French, J.J.; Page, R.W.; Bertoldi, G.L.

    1982-01-01

    Preliminary data are presented for the first of seven test holes drilled as a part of the Central Valley Aquifer Project which is part of the National Regional Aquifer Systems Analysis Program. The test hole was drilled in the SW 1/4 SE 1/4 sec. 34, T. 12 N. , R. 1 E., Yolo County, California, about 3 miles northeast of the town of Zamora. Drilled to a depth of 2,500 feet below land surface, the hole is cased to a depth of 190 feet and equipped with three piezometer tubes to depths of 947, 1,401, and 2,125 feet. A 5-foot well screen is at the bottom of each piezometer. Eighteen cores and 68 sidewall cores were recovered. Laboratory tests were made for mineralogy, hydraulic conductivity, porosity , consolidation, grain-size distribution, Atterberg limits, X-ray diffraction, diatom identification, thermal conductivity, and chemical analysis of water. Geophysical and thermal gradient logs were made. The hole is sampled periodically for chemical analysis and measured for water level in the three tapped zones. This report presents methods used to obtain field samples, laboratory procedures, and the data obtained. (USGS)

  9. Comparison of Summer and Winter California Central Valley Aerosol Distributions from Lidar and MODIS Measurements

    NASA Technical Reports Server (NTRS)

    Lewis, Jasper; DeYoung, Russell; Ferrare, Richard; Chu, D. Allen

    2010-01-01

    Aerosol distributions from two aircraft lidar campaigns conducted in the California Central Valley are compared in order to identify seasonal variations. Aircraft lidar flights were conducted in June 2003 and February 2007. While the ground PM(sub 2.5) concentration is highest in the winter, the aerosol optical depth measured from MODIS is highest in the summer. A seasonal comparison shows that PM(sub 2.5) in the winter can exceed summer PM(sub 2.5) by 55%, while summer AOD exceeds winter AOD by 43%. Higher temperatures and wildfires in the summer produce elevated aerosol layers that are detected by satellite measurements, but not surface particulate matter monitors. Temperature inversions, especially during the winter, contribute to higher PM(sub 2.5) measurements at the surface. Measurements of the boundary layer height from lidar instruments provide valuable information need to understand the relationship between satellite measurements of optical depth and in-situ measurements of PM(sub 2.5).

  10. Present-day crustal motion along the Longitudinal Valley Fault, eastern Taiwan

    NASA Astrophysics Data System (ADS)

    Yu, Shui-Beih; Kuo, Long-Chen

    2001-04-01

    The NNE-striking Longitudinal Valley Fault (LVF) in eastern Taiwan is an extremely active high-angle thrust fault. It bounds the Coastal Range and the Longitudinal Valley, which is considered a collision boundary between the Philippine Sea and the Eurasian plates. Repeated GPS data in the Longitudinal Valley area from 1992 to 1999 are utilized to study the spatial variation of crustal motion along the LVF. With respect to Penghu in the Chinese continental margin, velocities for stations on the western side of the LVF (Longitudinal Valley and eastern Central Range) are 18-35 mm/yr in directions 283-311°, whereas those on the eastern side of the LVF, the Coastal Range, are 28-68 mm/yr in directions 303-324°. A major discontinuity of about 30 mm/yr on the rate of crustal motion across the Longitudinal Valley is attributed to the aseismic slip along the LVF as revealed by trilateration data previously. To the south of Fengping, the block motions of the Coastal Range are 31-40 mm/yr in 317-330° relative to the Central Range, while the near-fault motions are 13-33 mm/yr in 309-336°. Various partitions on the left-lateral strike-slip and convergent components along the LVF are found. In the southern Longitudinal Valley crustal motion is mainly accommodated on the LVF and the Luyeh Fault. In contrast, those in the central and northern Longitudinal Valley are partly taken up on the faults to the east of the LVF or result in the elastic deformation of the Coastal Range. The crustal motion in the northern Longitudinal Valley area is likely to be distributed in the several NE-striking thrusts in a horsetail pattern and obliquely cut the northern Coastal Range, with a small portion of fault-slips along the LVF. Data from dense-deployed GPS networks across the LVF can be employed to give better estimates of near-fault motions and delineate the surface traces of the LVF. Repeated GPS and leveling data from two stations on both ends of the Yuli Bridge that are 575 m apart

  11. Summer mistral at the exit of the Rhône valley

    NASA Astrophysics Data System (ADS)

    Drobinski, P.; Bastin, S.; Guenard, V.; Caccia, J. L.; Dabas, A. M.; Delville, P.; Protat, A.; Reitebuch, O.; Werner, C.

    2005-01-01

    The paper examines the three-dimensional structure and dynamics of the mistral at the Rhône valley exit on 28 June 2001. The mistral refers to a severe wind that develops along the Rhône valley in southern France. This summer mistral event was documented in the framework of the ESCOMPTE field experiment. The dynamical processes driving the circulation of the mistral in the Rhône valley and particularly wake formation and planetary boundary layer (PBL) inhomogeneity at the scale of Rhône valley delta are investigated. Several important data sources are used (airborne Doppler lidar, radiosondes and surface stations) as well as non-hydrostatic mesoscale simulations. This paper analyses experimentally, numerically and theoretically the mechanism of wake formation. It shows that the flow impinging on the Alpine range and the Massif Central becomes supercritical all along the ridge line, including the Rhône valley and continues to accelerate in the lee regions until a hydraulic jump occurs. It leads to the formation of wakes behind and close to the mountain peaks. Compared to the Massif Central wake, the origin of the western Alps wake is rather complicated. In this study, the observations and simulations suggest a combined wall separation/gravity wave breaking mechanism to explain the western Alps wake. Indeed, it is shown that in addition to the flow descending the western Alps slopes and experiencing a strong hydraulic jump, the point where the mistral flow separates from the eastern flank of the Rhône valley located at about 44°N is associated with a 'flank-shock' which is an oblique hydraulic jump (i.e.the downstream Froude number is supercritical). Wake formation in the lee of the Alps and the Massif Central causes large inhomogeneity of the PBL with differences between land and sea. In the Massif Central and western Alps wakes, the continental PBL is deeper (1.8 km) than in the mistral flow (1 km), which is consistent with a subcritical regime associated

  12. Changes in biodiversity and ecosystem function downstream from mountaintop removal and valley fill coal mining

    EPA Science Inventory

    Mountaintop removal and valley fill coal mining has altered the physicochemical landscape of the Central Appalachian region in the U.S. Increased specific conductance and levels of component ions downstream from valley fill sites are toxic to aquatic life and can negatively impa...

  13. Geophysical Data from Spring Valley to Delamar Valley, East-Central Nevada

    USGS Publications Warehouse

    Mankinen, Edward A.; Roberts, Carter W.; McKee, Edwin H.; Chuchel, Bruce A.; Morin, Robert L.

    2007-01-01

    Cenozoic basins in eastern Nevada and western Utah constitute major ground-water recharge areas in the eastern part of the Great Basin and these were investigated to characterize the geologic framework of the region. Prior to these investigations, regional gravity coverage was variable over the region, adequate in some areas and very sparse in others. Cooperative studies described herein have established 1,447 new gravity stations in the region, providing a detailed description of density variations in the middle to upper crust. All previously available gravity data for the study area were evaluated to determine their reliability, prior to combining with our recent results and calculating an up-to-date isostatic residual gravity map of the area. A gravity inversion method was used to calculate depths to pre-Cenozoic basement rock and estimates of maximum alluvial/volcanic fill in the major valleys of the study area. The enhanced gravity coverage and the incorporation of lithologic information from several deep oil and gas wells yields a much improved view of subsurface shapes of these basins and provides insights useful for the development of hydrogeologic models for the region.

  14. Runoff simulation in the Ferghana Valley (Central Asia) using conceptual hydrological HBV-light model

    NASA Astrophysics Data System (ADS)

    Radchenko, Iuliia; Breuer, Lutz; Forkutsa, Irina; Frede, Hans-Georg

    2013-04-01

    Glaciers and permafrost on the ranges of the Tien Shan mountain system are primary sources of water in the Ferghana Valley. The water artery of the valley is the Syr Darya River that is formed by confluence of the Naryn and Kara Darya rivers, which originate from the mountain glaciers of the Ak-Shyrak and the Ferghana ranges accordingly. The Ferghana Valley is densely populated and main activity of population is agriculture that heavily depends on irrigation especially in such arid region. The runoff reduction is projected in future due to global temperature rise and glacier shrinkage as a consequence. Therefore, it is essential to study climate change impact on water resources in the area both for ecological and economic aspects. The evaluation of comparative contribution of small upper catchments (n=24) with precipitation predominance in discharge and the large Naryn and Karadarya River basins, which are fed by glacial melt water, to the Fergana Valley water balance under current and future climatic conditions is general aim of the study. Appropriate understanding of the hydrological cycle under current climatic conditions is significant for prognosis of water resource availability in the future. Thus, conceptual hydrological HBV-light model was used for analysing of the water balance of the small upper catchments that surround the Ferghana Valley. Three trial catchments (the Kugart River basin, 1010 km²; the Kurshab River basin, 2010 km2; the Akbura River basin, 2260 km²) with relatively good temporal quality data were chosen to setup the model. Due to limitation of daily temperature data the MODAWEC weather generator, which converts monthly temperature data into daily based on correlation with rainfall, was tested and applied for the HBV-light model.

  15. Ethiopian Central Rift Valley basin hydrologic modelling using HEC-HMS and ArcSWAT

    NASA Astrophysics Data System (ADS)

    Pascual-Ferrer, Jordi; Candela, Lucila; Pérez-Foguet, Agustí

    2013-04-01

    An Integrated Water Resources Management (IWRM) shall be applied to achieve a sustainable development, to increase population incomes without affecting lives of those who are highly dependent on the environment. First step should be to understand water dynamics at basin level, starting by modeling the basin water resources. For model implementation, a large number of data and parameters are required, but those are not always available, especially in some developing countries where different sources may have different data, there is lack of information on data collection, etc. The Ethiopian Central Rift Valley (CRV) is an endorheic basin covering an area of approximately 10,000 km2. For the period 1996-2005, the average annual volume of rainfall accounted for 9.1 Mm3, and evapotranspiration for 8 Mm3 (Jansen et al., 2007). From the environmental point of view, basin ecosystems are endangered due to human activities. Also, poverty is widespread all over the basin, with population mainly living from agriculture on a subsistence economy. Hence, there is an urgent need to set an IWRM, but datasets required for water dynamics simulation are not too reliable. In order to reduce uncertainty of numerical simulation, two semi-distributed open software hydrologic models were implemented: HEC-HMS and ArcSWAT. HEC-HMS was developed by the United States Army Corps of Engineers (USACoE) Hydrologic Engineering Center (HEC) to run precipitation-runoff simulations for a variety of applications in dendritic watershed systems. ArcSWAT includes the SWAT (Soil and Water Assessment Tool, Arnold et al., 1998) model developed for the USDA Agricultural Research Service into ArcGIS (ESRI®). SWAT was developed to assess the impact of land management practices on large complex watersheds with varying soils, land use and management conditions over long periods of time (Neitsch et al., 2005). According to this, ArcSWAT would be the best option for IWRM implementation in the basin. However

  16. Quality of groundwater and surface water, Wood River Valley, south-central Idaho, July and August 2012

    USGS Publications Warehouse

    Hopkins, Candice B.; Bartolino, James R.

    2013-01-01

    Residents and resource managers of the Wood River Valley of south-central Idaho are concerned about the effects that population growth might have on the quality of groundwater and surface water. As part of a multi-phase assessment of the groundwater resources in the study area, the U.S. Geological Survey evaluated the quality of water at 45 groundwater and 5 surface-water sites throughout the Wood River Valley during July and August 2012. Water samples were analyzed for field parameters (temperature, pH, specific conductance, dissolved oxygen, and alkalinity), major ions, boron, iron, manganese, nutrients, and Escherichia coli (E.coli) and total coliform bacteria. This study was conducted to determine baseline water quality throughout the Wood River Valley, with special emphasis on nutrient concentrations. Water quality in most samples collected did not exceed U.S. Environmental Protection Agency standards for drinking water. E. coli bacteria, used as indicators of water quality, were detected in all five surface-water samples and in two groundwater samples collected. Some analytes have aesthetic-based recommended drinking water standards; one groundwater sample exceeded recommended iron concentrations. Nitrate plus nitrite concentrations varied, but tended to be higher near population centers and in agricultural areas than in tributaries and less populated areas. These higher nitrate plus nitrite concentrations were not correlated with boron concentrations or the presence of bacteria, common indicators of sources of nutrients to water. None of the samples collected exceeded drinking-water standards for nitrate or nitrite. The concentration of total dissolved solids varied considerably in the waters sampled; however a calcium-magnesium-bicarbonate water type was dominant (43 out of 50 samples) in both the groundwater and surface water. Three constituents that may be influenced by anthropogenic activity (chloride, boron, and nitrate plus nitrite) deviate from this

  17. Geophysical setting of the Wabash Valley fault system

    USGS Publications Warehouse

    Hildenbrand, T.G.; Ravat, D.

    1997-01-01

    Interpretation of existing regional magnetic and gravity data and new local high-resolution aeromagnetic data provides new insights on the tectonic history and structural development of the Wabash Valley Fault System in Illinois and Indiana. Enhancement of short-wavelength magnetic anomalies reveal numerous NW- to NNE-trending ultramafic dikes and six intrusive complexes (including those at Hicks Dome and Omaha Dome). Inversion models indicate that the interpreted dikes are narrow (???3 m), lie at shallow depths (500 km long and generally >50 km wide) and with deep basins (locally >3 km thick), the ancestral Wabash Valley faults express, in comparison, minor tectonic structures and probably do not represent a failed rift arm. There is a lack of any obvious relation between the Wabash Valley Fault System and the epicenters of historic and prehistoric earthquakes. Five prehistoric earthquakes lie conspicuously near structures associated with the Commerce geophysical lineament, a NE-trending magnetic and gravity lineament lying oblique to the Wabash Valley Fault System and possibly extending over 600 km from NE Arkansas to central Indiana.

  18. Surficial Geologic Map of the Death Valley Junction 30' x 60' Quadrangle, California and Nevada

    USGS Publications Warehouse

    Slate, Janet L.; Berry, Margaret E.; Menges, Christopher M.

    2009-01-01

    This surficial geologic map of the Death Valley Junction 30' x 60' quadrangle was compiled digitally at 1:100,000 scale. The map area covers the central part of Death Valley and adjacent mountain ranges - the Panamint Range on the west and the Funeral Mountains on the east - as well as areas east of Death Valley including some of the Amargosa Desert, the Spring Mountains and Pahrump Valley. Shaded relief delineates the topography and appears as gray tones in the mountain ranges where the bedrock is undifferentiated and depicted as a single unit.

  19. Floods of November-December 1950 in the Central Valley basin, California

    USGS Publications Warehouse

    Paulsen, C.G.

    1953-01-01

    The flood of November-December 1950 in the Central Valley basin was the greatest in most parts of the basin since the turn of the century and probably was exceeded in the lower San Joaquin River basin only by the historic flood of 1862. In respect to monetary loss, the 1950 flood was the most disastrous in the history of the basin. Loss of life was remarkably small when one considers the extensive damage and destruction to homes and other property, which is estimated at 33 million dollars. Outstanding features of the flood were its unprecedented occurrence so early in the winter flood season, its magnitude in respect to both peak and volume in most major tributaries, and the occurrence of a succession of near-peak flows with a period of three weeks. The flood was caused by a series of storms during the period November 16 to December 8, which brought exceptionally warm, moisture-laden air inland against the Sierra Nevada range and caused intense rainfall, instead of snowfall, at unusually high altitudes. Basin-wide totals of rainfall during the period ranged from 30 inches over the Yuba and American River basins to 13 inches over the upper Sacramento and Feather River basins. Based on continuous records of discharge on major tributaries for periods ranging from 22 to 55 years and averaging about 43 years, the 1950 flood peaks were the greatest of record on the American, Cosumnes, Mokelumne, Stanislaus, Tuolumne, Merced, Chowchilla, Fresno, lower San Joaquin, Kings, Kaweah, Tule, and Kern Rivers. Second highest peak of record occurred during the flood of March 1928 on the Yuba, American and Mokelumne Rivers; the flood of Marcn 1940 on Cosumnes River; the flood of January 1911 on the Stanislaus and Tuolumne Rivers; the flood of December 1937 on the Merced, Kings, and Kaweah Rivers; the flood of March 1938 on the Chowchilla, Fresno, and lower San Joaquin Rivers; and the flood of March 1943 on the Tule and Kern Rivers. Peak discharges for 1950 did not exceed previous

  20. The Effects of Mountaintop Mines and Valley Fills on Aquatic ...

    EPA Pesticide Factsheets

    EPA announced the availability of the final report, The Effects of Mountaintop Mines and Valley Fills on Aquatic Ecosystems of the Central Appalachian Coalfields. This report assesses the state of the science on the environmental impacts of mountaintop mines and valley fills (MTM-VF) on streams in the central Appalachian coalfields. These coalfields cover about 48,000 square kilometers (122 million acres) in West Virginia, Kentucky, Virginia and Tennessee, USA. Our reviews focused on the impacts on mountaintop removal coal mining, which as its name suggests, involves removing all or some portion of the top of a mountain or ridge to expose and mine one or more coal seams. The excess overburden is disposed of in constructed fills in small valleys or hollows adjacent to the mining site. Our conclusions, based on evidence from the peer-reviewed literature and from the U.S. Environmental Protection Agency's Programmatic Environmental Impact Statement released in 2005, are that mountaintop mines and valley fills lead directly to five principal alterations of stream ecosystems: springs and ephemeral, intermittent and perennial streams are permanently lost with the removal of the mountain and from burial under fill, concentrations of major chemical ions are persistently elevated downstream, degraded water quality reaches levels that are acutely lethal to organisms in standard aquatic toxicity tests, selenium concentrations are elevated, reaching concentrations t

  1. Ecosystem Services Mapping for Sustainable Agricultural Water Management in California's Central Valley.

    PubMed

    Matios, Edward; Burney, Jennifer

    2017-03-07

    Accurate information on agricultural water needs and withdrawals at appropriate spatial and temporal scales remains a key limitation to joint water and land management decision-making. We use InVEST ecosystem service mapping to estimate water yield and water consumption as functions of land use in Fresno County, a key farming region in California's Central Valley. Our calculations show that in recent years (2010-2015), the total annual water yield for the county has varied dramatically from ∼0.97 to 5.37 km 3 (all ±17%; 1 MAF ≈ 1.233 km 3 ), while total annual water consumption has changed over a smaller range, from ∼3.37 to ∼3.98 km 3 (±20%). Almost all of the county's water consumption (∼96% of total use) takes place in Fresno's croplands, with discrepancy between local annual surface water yields and crop needs met by surface water allocations from outside the county and, to a much greater extent, private groundwater irrigation. Our estimates thus bound the amount of groundwater needed to supplement consumption each year (∼1.76 km 3 on average). These results, combined with trends away from field crops and toward orchards and vineyards, suggest that Fresno's land and water management have become increasingly disconnected in recent years, with the harvested area being less available as an adaptive margin to hydrological stress.

  2. "Nuestro camino es más largo" (Our Journey Is Much Longer): A "Testimonio" of Immigrant Life in the Central Valley and the Road towards the Professoriate

    ERIC Educational Resources Information Center

    Jiménez, Rosa M.

    2016-01-01

    Throughout my life I have come home to Modesto, California more times than my heart can remember; it is my heart that remembers and keeps my hometown ever present. Today, I am an Assistant Professor at the University of San Francisco. Yet, who I am today is profoundly intertwined with the little girl who grew up in the Central Valley as a daughter…

  3. Ground water in the Escalante Valley, Beaver, Iron, and Washington Counties, Utah

    USGS Publications Warehouse

    Fix, Philip F.; Nelson, W.B.; Lofgren, B.E.; Butler, R.G.

    1950-01-01

    Escalante Valley in southwestern Utah is one of the largest and most important ground-water areas of the State, with 1,300 square miles of arid land and an additional 1,500 square miles in its tributary drainage basin. Ground water is obtained from gravel and sand beds in the unconsolidated valley fill. In 1950 more irrigation wells were pumped than in any other basin of Utah, and their total pumpage exceeded 80,000 acre-feet. Farming is done chiefly in the Beryl-Enterprise district at the south (upper) end of the valley, where it depends almost entirely upon ground water, and in the Milford and Minersville districts in the northeast-central part of the valley. This progress report concerns chiefly the Beryl-Enterprise and Milford districts.

  4. Rift Valley Fever Virus Circulating among Ruminants, Mosquitoes and Humans in the Central African Republic.

    PubMed

    Nakouné, Emmanuel; Kamgang, Basile; Berthet, Nicolas; Manirakiza, Alexandre; Kazanji, Mirdad

    2016-10-01

    Rift Valley fever virus (RVFV) causes a viral zoonosis, with discontinuous epizootics and sporadic epidemics, essentially in East Africa. Infection with this virus causes severe illness and abortion in sheep, goats, and cattle as well as other domestic animals. Humans can also be exposed through close contact with infectious tissues or by bites from infected mosquitoes, primarily of the Aedes and Culex genuses. Although the cycle of RVFV infection in savannah regions is well documented, its distribution in forest areas in central Africa has been poorly investigated. To evaluate current circulation of RVFV among livestock and humans living in the Central African Republic (CAR), blood samples were collected from sheep, cattle, and goats and from people at risk, such as stock breeders and workers in slaughterhouses and livestock markets. The samples were tested for anti-RVFV immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies. We also sequenced the complete genomes of two local strains, one isolated in 1969 from mosquitoes and one isolated in 1985 from humans living in forested areas. The 1271 animals sampled comprised 727 cattle, 325 sheep, and 219 goats at three sites. The overall seroprevalence of anti-RVFV IgM antibodies was 1.9% and that of IgG antibodies was 8.6%. IgM antibodies were found only during the rainy season, but the frequency of IgG antibodies did not differ significantly by season. No evidence of recent RVFV infection was found in 335 people considered at risk; however, 16.7% had evidence of past infection. Comparison of the nucleotide sequences of the strains isolated in the CAR with those isolated in other African countries showed that they belonged to the East/Central African cluster. This study confirms current circulation of RVFV in CAR. Further studies are needed to determine the potential vectors involved and the virus reservoirs.

  5. Unexpected Rift Valley Fever Outbreak, Northern Mauritania

    PubMed Central

    El Mamy, Ahmed B. Ould; Baba, Mohamed Ould; Barry, Yahya; Isselmou, Katia; Dia, Mamadou L.; Hampate, Ba; Diallo, Mamadou Y.; El Kory, Mohamed Ould Brahim; Diop, Mariam; Lo, Modou Moustapha; Thiongane, Yaya; Bengoumi, Mohammed; Puech, Lilian; Plee, Ludovic; Claes, Filip; Doumbia, Baba

    2011-01-01

    During September–October 2010, an unprecedented outbreak of Rift Valley fever was reported in the northern Sahelian region of Mauritania after exceptionally heavy rainfall. Camels probably played a central role in the local amplification of the virus. We describe the main clinical signs (hemorrhagic fever, icterus, and nervous symptoms) observed during the outbreak. PMID:22000364

  6. Inca expansion and parasitism in the lluta valley: preliminary data.

    PubMed

    Santoro, Calogero; Vinton, Sheila Dorsey; Reinhard, Karl J

    2003-01-01

    Assessing the impact of cultural change on parasitism has been a central goal in archaeoparasitology. The influence of civilization and the development of empires on parasitism has not been evaluated. Presented here is a preliminary analysis of the change in human parasitism associated with the Inca conquest of the Lluta Valley in Northern Chile. Changes in parasite prevalence are described. It can be seen that the change in life imposed on the inhabitants of the Lluta Valley by the Incas caused an increase in parasitism.

  7. Sex-related differences in habitat associations of wintering American Kestrels in California's Central Valley

    USGS Publications Warehouse

    Pandolfino, E.R.; Herzog, M.P.; Smith, Z.

    2011-01-01

    We used roadside survey data collected from 19 routes over three consecutive winters from 200708 to 200910 to compare habitat associations of male and female American Kestrels (Falco sparverius) in the Central Valley of California to determine if segregation by sex was evident across this region. As a species, American Kestrels showed positive associations with alfalfa and other forage crops like hay and winter wheat, as well as grassland, irrigated pasture, and rice. Habitat associations of females were similar, with female densities in all these habitats except rice significantly higher than average. Male American Kestrels showed a positive association only with grassland and were present at densities well below those of females in alfalfa, other forage crops, and grassland. Males were present in higher densities than females in most habitats with negative associations for the species, such as orchards, urbanized areas, and oak savannah. The ratio of females to males for each route was positively correlated with the overall density of American Kestrels on that route. Our findings that females seem to occupy higher quality habitats in winter are consistent with observations from elsewhere in North America. ?? 2011 The Raptor Research Foundation, Inc.

  8. Regional soil geochemistry in the Ojailen Valley: a realm dominated by the industrial and mining city of Puertollano (South Central Spain)

    NASA Astrophysics Data System (ADS)

    López-Berdonces, Miguel; Fernandez-Calderón, Sergio; Higueras, Pablo; María Esbrí, Jose; Gonzalez-Corrochano, Beatríz; García-Noguero, Eva Mª; Martínez-Coronado, Alba; García-Noguero, Carolina

    2013-04-01

    Regional soil geochemistry in the Ojailén Valley: a realm dominated by the industrial and mining city of Puertollano (South Central Spain). Authors: Miguel A. López-Berdonces¹; Sergio Fernández Calderón¹; Pablo Higueras¹; José María Esbrí¹; Beatriz González-Corrochano¹; Eva Mª García-Noguero¹; Alba Martínez-Coronado¹; Carolina García Noguero¹ ¹Instituto de Geología Aplicada, Universidad de Castilla La Mancha, Almadén 13400 (Spain). Ojailén Valley is situated in South Central of Spain, an area where livestock, agriculture, mining and industry coexist. This work tries to assess the relationships between these activities and local environmental compartments: water, soils and heavy metal contents, and establish the most appropriate methodology of sample treatment and analytical techniques that can be employed on this kind of studies. For soil geochemistry, 152 samples were taken at two different depths, one at surface layer and another at 20 cm depth, and establish relationships between them and the possible sources. For this purpose, we determine soil parameters (pH, conductivity and organic matter) and total metal contents by Energy Dispersion of X Ray Fluorescence (EDXRF). Samples with higher nickel contents were analyzed with Inductive Coupled Plasma Spectroscopy (ICP-OES) after acid digestion. The study of surface waters includes 18 samples along the river and tributaries near mining and industrial areas. Water analysis was performed by ICP-OES. Soil samples shows pH between 6 and 8.5, highest located near on the east part of the valley, in the vicinity of petrochemical complex. Conductivity values show higher levels (1600 µS cm¯¹) in the vicinity of Puertollano and the industrial sites. Local reference value (LRV) for contaminated soils were determined according to the methodology proposed by Jimenez-Ballesta et al. (2010), using the equation: LRV=GM + 2SD, where LRV: Local Reference Value, GM: Geometric Mean, SD: Standard Deviation

  9. Hydrologic effects of stress-relief fracturing in an Appalachian Valley

    USGS Publications Warehouse

    Wyrick, Granville G.; Borchers, James W.

    1981-01-01

    A hydrologic study at Twin Falls State Park, Wyoming County, West Virginia, was made to determine how fracture systems affect the occurrence and movement of ground water in a typical valley of the Appalachian Plateaus Physiographic Province. Twin Falls was selected because it is generally unaffected by factors that would complicate an analysis of the data. The study area was the Black Fork Valley at Twin Falls. The valley is about 3 miles long and 400 to 600 feet wide and is cut into massive sandstone units interbedded with thin coal and shale beds. The study was made to determine how aquifer characteristics were related to fracture systems in this valley, so that the relation could be applied to studies of other valleys. Two sites were selected for test drilling, pumping tests, and geophysical studies. One site is in the upper part of the valley, and the second is near the lower central part. At both sites, ground water occurs mainly in horizontal bedding-plane fractures under the valley floor and in nearly vertical and horizontal slump fractures along the valley wall. The aquifer is under confined conditions under the valley floor and unconfined conditions along the valley wall. The fractures pinch out under the valley walls, which form impermeable barriers. Tests of wells near the valley center indicated a change in storage coefficient as the cone of depression caused by pumping reached the confined-unconfined boundaries; the tests also indicated barrier-image effects when the cone reached the impermeable boundaries. Drawdown from pumping near the center of the valley affected water levels at both sites, indicating a hydraulic connection from the upper to the lower end of the valley. Stream gain-and-loss studies show that ground water discharges to the stream from horizontal fractures beneath Black Fork Falls, near the mouth of Black Fork. The fracture systems that constitute most of the transmissive part of the aquifer at Twin Falls are like those described as

  10. Central Avra Valley Storage and Recovery Project (CAVSARP) Site, Tucson, Arizona: Floodwater and Soil Moisture Investigations with Extraterrestrial Applications

    NASA Technical Reports Server (NTRS)

    Rucker, D. F.; Dohm, J. M.; Ferre, T. P. A.; Ip, Felipe; Baker, V. R.; Davies, A. G.; Castano, R.; Chien, S.; Doggett, T. C.

    2004-01-01

    Planetary geologists, geomorphologists, and hydrologists have hypothesized that Mars is a dynamic, water-enriched planet since the Mariner and Viking missions based on geologic, geomorphic, and topographic information. Recent acquisition of Gamma Ray and Neutron Spectrometer information has added further credence to this hypothesis. A unique investigation is underway to work towards being able to successfully map the extent and depth of water on Mars. Researchers from the University of Arizona and members of the Autonomous Sciencecraft Experiment (ASE) have been compiling multiple layers of information in time and space at the Central Avra Valley Storage and Recovery Project (CAVSARP) site, Tucson, Arizona, for eventual comparative analysis. This information has been acquired from a variety of observational/scientific platforms in controlled conditions. CAVSARP facility:

  11. Ground-Water Budgets for the Wood River Valley Aquifer System, South-Central Idaho, 1995-2004

    USGS Publications Warehouse

    Bartolino, James R.

    2009-01-01

    The Wood River Valley contains most of the population of Blaine County and the cities of Sun Valley, Ketchum, Haley, and Bellevue. This mountain valley is underlain by the alluvial Wood River Valley aquifer system which consists of a single unconfined aquifer that underlies the entire valley, an underlying confined aquifer that is present only in the southernmost valley, and the confining unit that separates them. The entire population of the area depends on ground water for domestic supply, either from domestic or municipal-supply wells, and rapid population growth since the 1970s has caused concern about the long-term sustainability of the ground-water resource. To help address these concerns this report describes a ground-water budget developed for the Wood River Valley aquifer system for three selected time periods: average conditions for the 10-year period 1995-2004, and the single years of 1995 and 2001. The 10-year period 1995-2004 represents a range of conditions in the recent past for which measured data exist. Water years 1995 and 2001 represent the wettest and driest years, respectively, within the 10-year period based on precipitation at the Ketchum Ranger Station. Recharge or inflow to the Wood River Valley aquifer system occurs through seven main sources (from largest to smallest): infiltration from tributary canyons, streamflow loss from the Big Wood River, areal recharge from precipitation and applied irrigation water, seepage from canals and recharge pits, leakage from municipal pipes, percolation from septic systems, and subsurface inflow beneath the Big Wood River in the northern end of the valley. Total estimated mean annual inflow or recharge to the aquifer system for 1995-2004 is 270,000 acre-ft/yr (370 ft3/s). Total recharge for the wet year 1995 and the dry year 2001 is estimated to be 270,000 acre-ft/yr (370 ft3/s) and 220,000 acre-ft/yr (300 ft3/s), respectively. Discharge or outflow from the Wood River Valley aquifer system occurs through

  12. Resolving Large Pre-glacial Valleys Buried by Glacial Sediment Using Electric Resistivity Imaging (ERI)

    NASA Astrophysics Data System (ADS)

    Schmitt, D. R.; Welz, M.; Rokosh, C. D.; Pontbriand, M.-C.; Smith, D. G.

    2004-05-01

    Two-dimensional electric resistivity imaging (ERI) is the most exciting and promising geological tool in geomorphology and stratigraphy since development of ground-penetrating radar. Recent innovations in 2-D ERI provides a non-intrusive mean of efficiently resolving complex shallow subsurface structures under a number of different geological scenarios. In this paper, we test the capacity of ERI to image two large pre-late Wisconsinan-aged valley-fills in central Alberta and north-central Montana. Valley-fills record the history of pre-glacial and glacial sedimentary deposits. These fills are of considerable economical value as groundwater aquifers, aggregate resources (sand and gravel), placers (gold, diamond) and sometime gas reservoirs in Alberta. Although the approximate locations of pre-glacial valley-fills have been mapped, the scarcity of borehole (well log) information and sediment exposures make accurate reconstruction of their stratigraphy and cross-section profiles difficult. When coupled with borehole information, ERI successfully imaged three large pre-glacial valley-fills representing three contrasting geological settings. The Sand Coulee segment of the ancestral Missouri River, which has never been glaciated, is filled by electrically conductive pro-glacial lacustrine deposits over resistive sandstone bedrock. By comparison, the Big Sandy segment of the ancestral Missouri River valley has a complex valley-fill composed of till units interbedded with glaciofluvial gravel and varved clays over conductive shale. The fill is capped by floodplain, paludal and low alluvial fan deposits. The pre-glacial Onoway Valley (the ancestral North Saskatchewan River valley) is filled with thick, resistive fluvial gravel over conductive shale and capped with conductive till. The cross-sectional profile of each surveyed pre-glacial valley exhibits discrete benches (terraces) connected by steep drops, features that are hard to map using only boreholes. Best quality ERI

  13. When the School Is the Community: A Case Study of Fourche Valley School, Briggsville, Arkansas.

    ERIC Educational Resources Information Center

    Hadden, Patricia Demler

    Fourche Valley School District in central Arkansas has a single K-12 school serving 157 students. Surrounded by the Ouachita National Forest, Fourche Valley is unusually isolated and lacking in economic opportunity, leading to "low aspirations" among students who desire to remain in the area. Nevertheless, the school is thriving in the…

  14. Geology and ground water in Russian River Valley areas and in Round, Laytonville, and Little Lake Valleys, Sonoma and Mendocino Counties, California

    USGS Publications Warehouse

    Cardwell, G.T.

    1965-01-01

    This report describes the occurrence, availability, and quality of ground water in seven valley areas along the course of the Russian River in Sonoma and Mendocino Counties, Calif., and in three valleys in the upper drainage reach of the Eel River in Mendocino County. Except for the westward-trending lower Russian River valley, the remaining valley areas along the Russian River (Healdsburg, Alexander, Cloverdale, Sanel, Ukiah, and Potter Valleys) lie in northwest-trending structurally controlled depressions formed in marine rocks of Jurassic and Cretaceous age. The principal aquifer in all the valleys is the alluvium of Recent age, which includes highly permeable channel deposits of gravel and sand. Water for domestic, irrigation, industrial, and other uses is developed by (1) direct diversion from the Russian River and its tributaries, (2) withdrawal of ground water and river water from shallow wells near the river, and (3) withdrawals of ground water from wells in alluvial deposits at varying distances from the river. Surface water in the Russian River and most tributaries is of good chemical quality. The water is a calcium magnesium bicarbonate type and contains 75,200 parts per million of dissolved solids. Ground water is also of good chemical quality throughout most of the drainage basin, but the concentration of dissolved solids (100-300 parts per million) is somewhat higher than that in the surface water. Round, Laytonville, and Little Lake Valleys are in central and northern Mendocino County in the drainage basin of the northwestward flowing Eel River. In Round Valley the alluvium of Recent age yields water of good chemical quality in large quantities. Yields are lower and the chemical quality poorer in Laytonville Valley. Ground water in Little Lake Valley is relatively undeveloped. Selected descriptions of wells, drillers' logs, chemical analyses, and hydrographs showing water-level fluctuations are included in the report. Accompanying maps show the

  15. Sources of methane and nitrous oxide in California's Central Valley estimated through direct airborne flux and positive matrix factorization source apportionment of groundbased and regional tall tower measurements

    NASA Astrophysics Data System (ADS)

    Guha, Abhinav

    Methane (CH4) and nitrous oxide (N2O) are two major greenhouse gases that contribute significantly to the increase in anthropogenic radiative-forcing causing perturbations to the earth's climate system. In a watershed moment in the state's history of environmental leadership and commitment, California, in 2006, opted for sharp reductions in their greenhouse gas (GHG) emissions and adopted a long-term approach to address climate change that includes regulation of emissions from individual emitters and source categories. There are large CH4 and N2O emissions sources in the state, predominantly in the agricultural and waste management sector. While these two gases account for < 10% of total annual greenhouse gas emissions of the state, large uncertainties exist in their `bottom-up' accounting in the state GHG inventory. Additionally, an increasing number of `top-down' studies based on ambient observations point towards underestimation of their emissions in the inventory. Three intensive field observation campaigns that were spatially and temporally diverse took place between 2010 and 2013 in the Central Valley of California where the largest known sources of CH4 and N2O (e.g. agricultural systems and dairies) and potentially significant CH4 sources (e.g. oil and gas extraction) are located. The CalNex (California Nexus - Research at the Nexus of Air Quality and Climate Change) field campaign during summer 2010 (May 15 - June 30) took place in the urban core of Bakersfield in the southern San Joaquin Valley, a city whose economy is built around agriculture and the oil and gas industry. During summer of 2011, airborne measurements were performed over a large spatial domain, all across and around the Central Valley as part of the CABERNET (California Airborne BVOC Emission Research in Natural Ecosystem Transects) study. Next, a one-year continuous field campaign (WGC 2012-13, June 2012 - August 2013) was conducted at the Walnut Grove tall tower near the Sacramento

  16. Understanding surface-water availability in the Central Valley as a means to projecting future groundwater storage with climate variability

    NASA Astrophysics Data System (ADS)

    Goodrich, J. P.; Cayan, D. R.

    2017-12-01

    California's Central Valley (CV) relies heavily on diverted surface water and groundwater pumping to supply irrigated agriculture. However, understanding the spatiotemporal character of water availability in the CV is difficult because of the number of individual farms and local, state, and federal agencies involved in using and managing water. Here we use the Central Valley Hydrologic Model (CVHM), developed by the USGS, to understand the relationships between climatic variability, surface water inputs, and resulting groundwater use over the historical period 1970-2013. We analyzed monthly surface water diversion data from >500 CV locations. Principle components analyses were applied to drivers constructed from meteorological data, surface reservoir storage, ET, land use cover, and upstream inflows, to feed multiple regressions and identify factors most important in predicting surface water diversions. Two thirds of the diversion locations ( 80% of total diverted water) can be predicted to within 15%. Along with monthly inputs, representations of cumulative precipitation over the previous 3 to 36 months can explain an additional 10% of variance, depending on location, compared to results that excluded this information. Diversions in the southern CV are highly sensitive to inter-annual variability in precipitation (R2 = 0.8), whereby more surface water is used during wet years. Until recently, this was not the case in the northern and mid-CV, where diversions were relatively constant annually, suggesting relative insensitivity to drought. In contrast, this has important implications for drought response in southern regions (eg. Tulare Basin) where extended dry conditions can severely limit surface water supplies and lead to excess groundwater pumping, storage loss, and subsidence. In addition to fueling our understanding of spatiotemporal variability in diversions, our ability to predict these water balance components allows us to update CVHM predictions before

  17. Influence of system controls on the Late Quaternary geomorphic evolution of a rapidly-infilled incised-valley system: The lower Manawatu valley, North Island New Zealand

    NASA Astrophysics Data System (ADS)

    Clement, Alastair J. H.; Fuller, Ian C.

    2018-02-01

    The Manawatu incised-valley estuary was rapidly infilled between 12,000-4700 cal. yr BP. A combination of empirical measurements of sedimentation rates, a reconstruction of relative sea-level (RSL) change, and digital elevation models of key surfaces within the Holocene sedimentary fill of the valley were integrated to produce a numerical model to investigate the influence of the system controls of sea-level change, sediment flux, and accommodation space on the rapid infilling history of the palaeo-estuary. The numerical model indicates that sediment flux into the palaeo-estuary was greatest during the Holocene marine transgression between 12,000-8000 years BP. The average rate of sediment deposition in the estuary during this period was 1.0 M m3 yr- 1. This rapid rate of sedimentation was controlled by the rate of accommodation space creation, as regulated by the rate of sea-level rise and the antecedent configuration of the valley. By the time sea levels stabilised c. 7500 cal. yr BP, the palaeo-estuary had been substantively infilled. Limited accommodation space resulted in rapid infilling of the central basin, though sediment flux into the estuary between 7100 and 4500 cal. yr BP was at a lower rate of 234,000 m3 yr- 1. The limited accommodation space also influenced hydrodynamic conditions in the estuarine central basin, driving export of fine-grained sediment from the estuary. Once the accommodation space of the estuarine basin was infilled sediment bypassed the system, with a consequent reduction in the sedimentation rate in the valley. More accurate partitioning of the sources of sediment driving the infilling is necessary to quantify sediment bypassing. Post-depositional lowering of RSL index points from the valley is driven by neotectonics and sediment compaction.

  18. Data for ground-water test hole near Nicolaus, Central Valley aquifer project, California

    USGS Publications Warehouse

    French, James J.; Page, R.W.; Bertoldi, Gilbert L.

    1983-01-01

    Preliminary data are provided for the third of seven test holes drilled as a part of the Central Valley Aquifer Project which is part of the National Regional Aquifer Systems Analysis Program. The test hole was drilled in the SW 1/4 NE 1/4 sec. 2, T.12N., R.3E., Sutter County, California, about 1 1/2 miles northwest of the town of Nicolaus. Drilled to a depth of 1,150 feet below land surface, the hole is cased to a depth of 100 feet and equipped with three piezometer tubes to depths of 311, 711, and 1,071 feet. A 5-foot well screen is set in sand at the bottom of each piezometer. Each screened interval has a cement plug above and below it to isolate it from other parts of the aquifer, and the well bore is filled between the plugs with sediment. Thirty-one cores and 34 sidewall cores were recovered. Laboratory tests were made for minerology, consolidation, grain-size distribution, Atterberg limits, X-ray diffraction, thermal conductivity, and chemical analysis of water. Geophysical and thermal gradient logs were made. The hole is sampled periodically for chemical analysis of the three tapped zones and measured for water level. This report presents methods used to obtain field samples, laboratory procedures, and the data obtained. (USGS)

  19. Valley-dependent band structure and valley polarization in periodically modulated graphene

    NASA Astrophysics Data System (ADS)

    Lu, Wei-Tao

    2016-08-01

    The valley-dependent energy band and transport property of graphene under a periodic magnetic-strained field are studied, where the time-reversal symmetry is broken and the valley degeneracy is lifted. The considered superlattice is composed of two different barriers, providing more degrees of freedom for engineering the electronic structure. The electrons near the K and K' valleys are dominated by different effective superlattices. It is found that the energy bands for both valleys are symmetric with respect to ky=-(AM+ξ AS) /4 under the symmetric superlattices. More finite-energy Dirac points, more prominent collimation behavior, and new crossing points are found for K' valley. The degenerate miniband near the K valley splits into two subminibands and produces a new band gap under the asymmetric superlattices. The velocity for the K' valley is greatly renormalized compared with the K valley, and so we can achieve a finite velocity for the K valley while the velocity for the K' valley is zero. Especially, the miniband and band gap could be manipulated independently, leading to an increase of the conductance. The characteristics of the band structure are reflected in the transmission spectra. The Dirac points and the crossing points appear as pronounced peaks in transmission. A remarkable valley polarization is obtained which is robust to the disorder and can be controlled by the strain, the period, and the voltage.

  20. Selected hydrologic data for Cedar Valley, Iron County, southwestern Utah, 1930-2001

    USGS Publications Warehouse

    Howells, James H.; Mason, James L.; Slaugh, Bradley A.

    2001-01-01

    This report presents hydrologic data collected by the U. S. Geological Survey from 1930 to 2001 with emphasis on data collected from 1997 to 2001 as part of a study of ground-water resources in Cedar Valley, Iron County, southwestern Utah (fig. 1). Data collected prior to this study are also presented to show long-term trends. Data were collected during this study in cooperation with the Central Iron County Water Conservancy District; Utah Department of Natural Resources, Division of Water Resources; Utah Department of Environmental Quality, Division of Water Quality; Cedar City; and Enoch City; as part of a study to better understand the ground-water resources of Cedar Valley and to assess possible effects of increased ground-water withdrawal on water quality. Quality of ground water in Cedar Valley is variable and water suppliers need to know if additional water resources can be developed without drawing water of lower quality into public-supply wells.Cedar Valley is in central Iron County at the transitional boundary between the Basin and Range and Colorado Plateau physiographic provinces described by Hunt (1974) and covers about 570 mi2. Additional data from wells west of Cedar Valley and to the south in the vicinity of Kanarraville in the Virgin River drainage (Colorado River Basin) adjacent to the study area are included. Cedar Valley is bounded on the east by the Markagunt Plateau and Red Hills, on the southwest by the Harmony Mountains, on the west by a complex of low hills, and on the north by the Black Mountains. Altitudes in the study area range from about 5,300 ft in Mud Spring Canyon to about 10,400 ft at Blowhard Mountain to the east.

  1. Regional Evaluation of Groundwater Age Distributions Using Lumped Parameter Models with Large, Sparse Datasets: Example from the Central Valley, California, USA

    NASA Astrophysics Data System (ADS)

    Jurgens, B. C.; Bohlke, J. K.; Voss, S.; Fram, M. S.; Esser, B.

    2015-12-01

    Tracer-based, lumped parameter models (LPMs) are an appealing way to estimate the distribution of age for groundwater because the cost of sampling wells is often less than building numerical groundwater flow models sufficiently complex to provide groundwater age distributions. In practice, however, tracer datasets are often incomplete because of anthropogenic or terrigenic contamination of tracers, or analytical limitations. While age interpretations using such datsets can have large uncertainties, it may still be possible to identify key parts of the age distribution if LPMs are carefully chosen to match hydrogeologic conceptualization and the degree of age mixing is reasonably estimated. We developed a systematic approach for evaluating groundwater age distributions using LPMs with a large but incomplete set of tracer data (3H, 3Hetrit, 14C, and CFCs) from 535 wells, mostly used for public supply, in the Central Valley, California, USA that were sampled by the USGS for the California State Water Resources Control Board Groundwater Ambient Monitoring and Assessment or the USGS National Water Quality Assessment Programs. In addition to mean ages, LPMs gave estimates of unsaturated zone travel times, recharge rates for pre- and post-development groundwater, the degree of age mixing in wells, proportion of young water (<60 yrs), and the depth of the boundary between post-development and predevelopment groundwater throughout the Central Valley. Age interpretations were evaluated by comparing past nitrate trends with LPM predicted trends, and whether the presence or absence of anthropogenic organic compounds was consistent with model results. This study illustrates a practical approach for assessing groundwater age information at a large scale to reveal important characteristics about the age structure of a major aquifer, and of the water supplies being derived from it.

  2. Water transfer and major environmental provisions of the Central Valley Project Improvement Act: A preliminary economic evaluation

    NASA Astrophysics Data System (ADS)

    Loomis, John B.

    1994-06-01

    Increasing block water pricing, water transfer, and wildlife refuge water supply provisions of the Central Valley Project (CVP) Improvement Act are analyzed in terms of likely farmer response and economic efficiency of these provisions. Based on a simplified partial equilibrium analysis, we estimate small, but significant water conservation savings due to pricing reform, the potential for substantial water transfers to non-CVP customers in severe drought years when the water price exceeds 110 per acre foot (1 acre foot equals 1.234 × 103 m3) and positive net benefits for implementation of the wildlife refuge water supply provisions. The high threshold water price is partly a result of requiring farmers to pay full cost on transferred water plus a surcharge of 25 per acre foot if the water is transferred to a non-CVP user. The act also sets an important precedent for water pricing reform, water transfer provisions, and environmental surcharges on water users that may find their way to other Bureau of Reclamation projects.

  3. The Effects of Mountaintop Mines and Valley Fills on Aquatic ...

    EPA Pesticide Factsheets

    This report assesses the state of the science on the environmental impacts of mountaintop mines and valley fills (MTM-VF) on streams in the Central Appalachian Coalfields. Our review focused on the aquatic impacts of mountaintop removal coal mining, which, as its name suggests, involves removing all or some portion of the top of a mountain or ridge to expose and mine one or more coal seams. The excess overburden is disposed of in constructed fills in small valleys or hollows adjacent to the mining site. MTM-VF lead directly to five principal alterations of stream ecosystems: (1) springs, intermittent streams, and small perennial streams are permanently lost with the removal of the mountain and from burial under fill, (2) concentrations of major chemical ions are persistently elevated downstream, (3) degraded water quality reaches levels that are acutely lethal to standard laboratory test organisms, (4) selenium concentrations are elevated, reaching concentrations that have caused toxic effects in fish and birds and (5) macroinvertebrate and fish communities are consistently and significantly degraded. This report assesses the state of the science on the environmental impacts of Mountaintop Mines and Valley Fills (MTM-VF) on streams in the Central Appalachian Coalfields. The draft report will be externally peer reviewed by EPA's Science Advisory Board in early 2010.

  4. Comparison of two parametric methods to estimate pesticide mass loads in California's Central Valley

    USGS Publications Warehouse

    Saleh, Dina K.; Lorenz, David L.; Domagalski, Joseph L.

    2011-01-01

    Mass loadings were calculated for four pesticides in two watersheds with different land uses in the Central Valley, California, by using two parametric models: (1) the Seasonal Wave model (SeaWave), in which a pulse signal is used to describe the annual cycle of pesticide occurrence in a stream, and (2) the Sine Wave model, in which first-order Fourier series sine and cosine terms are used to simulate seasonal mass loading patterns. The models were applied to data collected during water years 1997 through 2005. The pesticides modeled were carbaryl, diazinon, metolachlor, and molinate. Results from the two models show that the ability to capture seasonal variations in pesticide concentrations was affected by pesticide use patterns and the methods by which pesticides are transported to streams. Estimated seasonal loads compared well with results from previous studies for both models. Loads estimated by the two models did not differ significantly from each other, with the exceptions of carbaryl and molinate during the precipitation season, where loads were affected by application patterns and rainfall. However, in watersheds with variable and intermittent pesticide applications, the SeaWave model is more suitable for use on the basis of its robust capability of describing seasonal variation of pesticide concentrations.

  5. Modeling nitrate at domestic and public-supply well depths in the Central Valley, California

    USGS Publications Warehouse

    Nolan, Bernard T.; Gronberg, JoAnn M.; Faunt, Claudia C.; Eberts, Sandra M.; Belitz, Ken

    2014-01-01

    Aquifer vulnerability models were developed to map groundwater nitrate concentration at domestic and public-supply well depths in the Central Valley, California. We compared three modeling methods for ability to predict nitrate concentration >4 mg/L: logistic regression (LR), random forest classification (RFC), and random forest regression (RFR). All three models indicated processes of nitrogen fertilizer input at the land surface, transmission through coarse-textured, well-drained soils, and transport in the aquifer to the well screen. The total percent correct predictions were similar among the three models (69–82%), but RFR had greater sensitivity (84% for shallow wells and 51% for deep wells). The results suggest that RFR can better identify areas with high nitrate concentration but that LR and RFC may better describe bulk conditions in the aquifer. A unique aspect of the modeling approach was inclusion of outputs from previous, physically based hydrologic and textural models as predictor variables, which were important to the models. Vertical water fluxes in the aquifer and percent coarse material above the well screen were ranked moderately high-to-high in the RFR models, and the average vertical water flux during the irrigation season was highly significant (p < 0.0001) in logistic regression.

  6. Land ownership dynamics in the Big Elk Valley in Oregon during the 20th century.

    Treesearch

    Brett J. Butler; Brooks J. Stanfield

    2002-01-01

    Land ownership is a key link between society and natural resources. The dynamics of landowner patterns are demonstrated by the examination of five land ownership maps in the Big Elk Valley of the central Oregon Coast Range. These patterns are further illustrated with the presentation of a land patents map of the Big Elk Valley. We selected this watershed because of its...

  7. Valley Fever: Earth Observations for Risk Reduction

    NASA Astrophysics Data System (ADS)

    Sprigg, W. A.

    2012-12-01

    Advances in satellite Earth observation systems, numerical weather prediction, and dust storm modeling yield new tools for public health warnings, advisories and epidemiology of illnesses associated with airborne desert dust. Valley Fever, endemic from California through the US/Mexico border region into Central and South America, is triggered by inhalation of soil-dwelling fungal spores. The path from fungal growth to airborne threat depends on environmental conditions observable from satellite. And space-based sensors provide initial conditions for dust storm forecasts and baselines for the epidemiology of Valley Fever and other dust-borne aggravation of respiratory and cardiovascular disease. A new Pan-American Center for the World Meteorological Organization Sand and Dust Storm Warning Advisory and Assessment System creates an opportunity to advance Earth science applications in public health.

  8. Estimates of natural ground-water discharge and characterization of water quality in Dry Valley, Washoe County, West-Central Nevada, 2002-2003

    USGS Publications Warehouse

    Berger, David L.; Maurer, Douglas K.; Lopes, Thomas J.; Halford, Keith J.

    2004-01-01

    The Dry Valley Hydrographic Area is being considered as a potential source area for additional water supplies for the Reno-Sparks area, which is about 25 miles south of Dry Valley. Current estimates of annual ground-water recharge to Dry Valley have a considerable range. In undeveloped valleys, such as Dry Valley, long-term ground-water discharge can be assumed the same as long-term ground-water recharge. Because estimating ground-water discharge has more certainty than estimating ground-water recharge from precipitation, the U.S. Geological Survey, in cooperation with Washoe County, began a three-year study to re-evaluate the ground-water resources by estimating natural ground-water discharge and characterize ground-water quality in Dry Valley. In Dry Valley, natural ground-water discharge occurs as subsurface outflow and by ground-water evapotranspiration. The amount of subsurface outflow from the upper part of Dry Valley to Winnemucca and Honey Lake Valleys likely is small. Subsurface outflow from Dry Valley westward to Long Valley, California was estimated using Darcy's Law. Analysis of two aquifer tests show the transmissivity of poorly sorted sediments near the western side of Dry Valley is 1,200 to 1,500 square feet per day. The width of unconsolidated sediments is about 4,000 feet between exposures of tuffaceous deposits along the State line, and decreases to about 1,500 feet (0.5 mile) west of the State line. The hydraulic gradient east and west of the State line ranges from 0.003 to 0.005 foot per foot. Using these values, subsurface outflow to Long Valley is estimated to be 50 to 250 acre-feet per year. Areas of ground-water evapotranspiration were field mapped and partitioned into zones of plant cover using relations derived from Landsat imagery acquired July 8, 2002. Evapotranspiration rates for each plant-cover zone were multiplied by the corresponding area and summed to estimate annual ground-water evapotranspiration. About 640 to 790 acre-feet per

  9. Modeling applications for precision agriculture in the California Central Valley

    NASA Astrophysics Data System (ADS)

    Marklein, A. R.; Riley, W. J.; Grant, R. F.; Mezbahuddin, S.; Mekonnen, Z. A.; Liu, Y.; Ying, S.

    2017-12-01

    Drought in California has increased the motivation to develop precision agriculture, which uses observations to make site-specific management decisions throughout the growing season. In agricultural systems that are prone to drought, these efforts often focus on irrigation efficiency. Recent improvements in soil sensor technology allow the monitoring of plant and soil status in real-time, which can then inform models aimed at improving irrigation management. But even on farms with resources to deploy soil sensors across the landscape, leveraging that sensor data to design an efficient irrigation scheme remains a challenge. We conduct a modeling experiment aimed at simulating precision agriculture to address several questions: (1) how, when, and where does irrigation lead to optimal yield? and (2) What are the impacts of different precision irrigation schemes on yields, soil organic carbon (SOC), and total water use? We use the ecosys model to simulate precision agriculture in a conventional tomato-corn rotation in the California Central Valley with varying soil water content thresholds for irrigation and soil water sensor depths. This model is ideal for our question because it includes explicit process-based functions for the plant growth, plant water use, soil hydrology, and SOC, and has been tested extensively in agricultural ecosystems. Low irrigation thresholds allows the soil to become drier before irrigating compared to high irrigation thresholds; as such, we found that the high irrigation thresholds use more irrigation over the course of the season, have higher yields, and have lower water use efficiency. The irrigation threshold did not affect SOC. Yields and water use are highest at sensor depths of 0.5 to 0.15 m, but water use efficiency was also lowest at these depths. We found SOC to be significantly affected by sensor depth, with the highest SOC at the shallowest sensor depths. These results will help regulate irrigation water while maintaining yield

  10. Geohydrology and Water Quality of the Valley-Fill Aquifer System in the Upper Sixmile Creek and West Branch Owego Creek Valleys in the Town of Caroline, Tompkins County, New York

    USGS Publications Warehouse

    Miller, Todd S.

    2009-01-01

    In 2002, the U.S. Geological Survey, in cooperation with the Town of Caroline and Tompkins County Planning Department, began a study of the valley-fill aquifer system in upper Sixmile Creek and headwaters of West Branch Owego Creek valleys in the Town of Caroline, NY. The purpose of the study is to provide geohydrologic data to county and town planners as they develop a strategy to manage and protect their water resources. The first aquifer reach investigated in this series is in the Town of Caroline and includes the upper Sixmile Creek valley and part of West Branch Owego Creek valley. The portions of the valley-fill aquifer system that are comprised of saturated coarse-grained sediments including medium to coarse sand and sandy gravel form the major aquifers. Confined sand and gravel units form the major aquifers in the western and central portions of the upper Sixmile Creek valley, and an unconfined sand and gravel unit forms the major aquifer in the eastern portion of the upper Sixmile Creek valley and in the headwaters of the West Branch Owego Creek valley. The valley-fill deposits are thinnest near the edges of the valley where they pinch out along the till-mantled bedrock valley walls. The thickness of the valley fill in the deepest part of the valley, at the western end of the study area, is about 100 feet (ft); the thickness is greater than 165 ft on top of the Valley Heads Moraine in the central part of the valley. An estimated 750 people live over and rely on groundwater from the valley-fill aquifers in upper Sixmile Creek and West Branch Owego Creek valleys. Most groundwater withdrawn from the valley-fill aquifers is pumped from wells with open-ended 6-inch diameter casings; the remaining withdrawals are from shallow dug wells or cisterns that collect groundwater that discharges to springs (especially in the Brooktondale area). The valley-fill aquifers are the sources of water for about 200 households, several apartment complexes, two mobile home parks

  11. Ground-water potentialities in the Crescent Valley, Eureka and Lander Counties, Nevada

    USGS Publications Warehouse

    Zones, Christie Paul

    1961-01-01

    The Crescent Valley is an intermontane basin in Eureka and Lander Counties, just south of the Humboldt River in north-central Nevada. The valley floor, with an area of about 150 square miles, has a shape that more nearly resembles a Y than a crescent, although the valley apparently was named after the arc described by its southern part and northeastern arm. The northwestern arm of the Y extends northward to the small railroad town of Beowawe on the Humboldt River; the northeastern arm lies east of the low Dry Hills. The leg of the Y extends southwestward toward a narrow gap which separates the Crescent Valley from the Carico Lake Valley. The total drainage area of the Crescent Valley-about 700 square miles--includes also the slopes of the bordering mountain ranges: the Shoshone Range to the west, the Cortez Mountains to the east, and the Toiyabe Range to the south. The early history of the Crescent Valley was dominated by mining of silver and gold, centered at Lander in the Shoshone Range and at Cortez and Mill Canyon in the Cortez Mountains, but in recent years the only major mining activity has been at Gold Acres; there open-pit mining of low-grade gold ore has supported a community of about 200. For many years the only agricultural enterprises in the valley were two cattle ranches, but recently addition lands have been developed for the raising of crops in the west-central part of the valley. The average annual precipitation upon the floor of the Crescent Valley is probably less than 7 inches, of which only a little more than 1 inch formally falls during the growing season (from June through September). This is far less than the requirement of any plants of economic value, and irrigation is essential to agricultural development. Small perennial streams rising in the mountains have long been utilized for domestic supply, mining and milling activities of the past, and irrigation, and recently some large wells have been developed for irrigation. In 1956 the total

  12. Adapting to climate variability and change: experiences from cereal-based farming in the central rift and Kobo Valleys, Ethiopia.

    PubMed

    Kassie, Belay Tseganeh; Hengsdijk, Huib; Rötter, Reimund; Kahiluoto, Helena; Asseng, Senthold; Van Ittersum, Martin

    2013-11-01

    Small-holder farmers in Ethiopia are facing several climate related hazards, in particular highly variable rainfall with severe droughts which can have devastating effects on their livelihoods. Projected changes in climate are expected to aggravate the existing challenges. This study examines farmer perceptions on current climate variability and long-term changes, current adaptive strategies, and potential barriers for successful further adaptation in two case study regions-the Central Rift Valley (CRV) and Kobo Valley. The study was based on a household questionnaire, interviews with key stakeholders, and focus group discussions. The result revealed that about 99 % of the respondents at the CRV and 96 % at the Kobo Valley perceived an increase in temperature and 94 % at CRV and 91 % at the Kobo Valley perceived a decrease in rainfall over the last 20-30 years. Inter-annual and intraseasonal rainfall variability also has increased according to the farmers. The observed climate data (1977-2009) also showed an increasing trend in temperature and high inter-annual and intra-seasonal rainfall variability. In contrast to farmers' perceptions of a decrease in rainfall totals, observed rainfall data showed no statistically significant decline. The interaction among various bio-physical and socio-economic factors, changes in rainfall intensity and reduced water available to crops due to increased hot spells, may have influenced the perception of farmers with respect to rainfall trends. In recent decades, farmers in both the CRV and Kobo have changed farming practices to adapt to perceived climate change and variability, for example, through crop and variety choice, adjustment of cropping calendar, and in situ moisture conservation. These relatively low-cost changes in farm practices were within the limited adaptation capacity of farmers, which may be insufficient to deal with the impacts of future climate change. Anticipated climate change is expected to impose new

  13. Adapting to Climate Variability and Change: Experiences from Cereal-Based Farming in the Central Rift and Kobo Valleys, Ethiopia

    NASA Astrophysics Data System (ADS)

    Kassie, Belay Tseganeh; Hengsdijk, Huib; Rötter, Reimund; Kahiluoto, Helena; Asseng, Senthold; Van Ittersum, Martin

    2013-11-01

    Small-holder farmers in Ethiopia are facing several climate related hazards, in particular highly variable rainfall with severe droughts which can have devastating effects on their livelihoods. Projected changes in climate are expected to aggravate the existing challenges. This study examines farmer perceptions on current climate variability and long-term changes, current adaptive strategies, and potential barriers for successful further adaptation in two case study regions—the Central Rift Valley (CRV) and Kobo Valley. The study was based on a household questionnaire, interviews with key stakeholders, and focus group discussions. The result revealed that about 99 % of the respondents at the CRV and 96 % at the Kobo Valley perceived an increase in temperature and 94 % at CRV and 91 % at the Kobo Valley perceived a decrease in rainfall over the last 20-30 years. Inter-annual and intraseasonal rainfall variability also has increased according to the farmers. The observed climate data (1977-2009) also showed an increasing trend in temperature and high inter-annual and intra-seasonal rainfall variability. In contrast to farmers’ perceptions of a decrease in rainfall totals, observed rainfall data showed no statistically significant decline. The interaction among various bio-physical and socio-economic factors, changes in rainfall intensity and reduced water available to crops due to increased hot spells, may have influenced the perception of farmers with respect to rainfall trends. In recent decades, farmers in both the CRV and Kobo have changed farming practices to adapt to perceived climate change and variability, for example, through crop and variety choice, adjustment of cropping calendar, and in situ moisture conservation. These relatively low-cost changes in farm practices were within the limited adaptation capacity of farmers, which may be insufficient to deal with the impacts of future climate change. Anticipated climate change is expected to impose new

  14. Modeling the long-term fate of agricultural nitrate in groundwater in the San Joaquin Valley, California

    USGS Publications Warehouse

    Chapelle, Francis H.; Campbell, Bruce G.; Widdowson, Mark A.; Landon, Mathew K.

    2013-01-01

    Nitrate contamination of groundwater systems used for human water supplies is a major environmental problem in many parts of the world. Fertilizers containing a variety of reduced nitrogen compounds are commonly added to soils to increase agricultural yields. But the amount of nitrogen added during fertilization typically exceeds the amount of nitrogen taken up by crops. Oxidation of reduced nitrogen compounds present in residual fertilizers can produce substantial amounts of nitrate which can be transported to the underlying water table. Because nitrate concentrations exceeding 10 mg/L in drinking water can have a variety of deleterious effects for humans, agriculturally derived nitrate contamination of groundwater can be a serious public health issue. The Central Valley aquifer of California accounts for 13 percent of all the groundwater withdrawals in the United States. The Central Valley, which includes the San Joaquin Valley, is one of the most productive agricultural areas in the world and much of this groundwater is used for crop irrigation. However, rapid urbanization has led to increasing groundwater withdrawals for municipal public water supplies. That, in turn, has led to concern about how contaminants associated with agricultural practices will affect the chemical quality of groundwater in the San Joaquin Valley. Crop fertilization with various forms of nitrogen-containing compounds can greatly increase agricultural yields. However, leaching of nitrate from soils due to irrigation has led to substantial nitrate contamination of shallow groundwater. That shallow nitrate-contaminated groundwater has been moving deeper into the Central Valley aquifer since the 1960s. Denitrification can be an important process limiting the mobility of nitrate in groundwater systems. However, substantial denitrification requires adequate sources of electron donors in order to drive the process. In many cases, dissolved organic carbon (DOC) and particulate organic carbon

  15. New exploration approach: Pennsylvanian Lower Tyler central Montana

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shepard, W.

    Modern exploration methods utilizing a plate tectonics structural model and a recent alluvial valley analog, the Brazos from the Texas Gulf Coast, have helped revive interest in Pennsylvanian Lower Tyler exploration in the central Montana petroleum province. The central Montana trough is now visualized as an aulacogen, reaching from the Rocky Mountain trench near Butte, Montana, eastward to the Williston basin. It is 60 mi wide by about 400 mi long. Pennsylvanian Lower Tyler sediments occur in this narrow east-west-trending rift system. The regional setting is an aulacogen, or intracratonic rift, that connected the Williston basin to the Cordilleran geosynclinemore » during much of geologic time, beginning in late Precambrian. The Lower Tyler is a westward-draining Pennsylvanian (Morrowan) alluvial valley-fill system consisting of a number of river valleys that funneled into the topographic low of the aulacogen. Rift-controlled, estuarine, euxinic limestones and shales above and below the Lower Tyler provide petroleum-rich source rocks. These source rocks are mature and have generated oil, probably in the Paleocene and early Eocene. The modern Brazos River Valley of southeastern Texas is a near mirror-image analog for Lower Tyler alluvial valley fill. The Brazos valleys are 6 mi wide, 150 to 300 ft thick, and contain 60 to 70% backswamp shales and silts. Point-bar sands constitute a relatively small portion of the valley fill; the sands are 60 to 70 ft thick and about 3000 ft wide. Diagenesis has decreased net porosity distribution in the Lower Tyler to less than that of the Brazos, yet porosity parameters may still be applied to exploration in the Tyler sandstones.« less

  16. Structure and Velocities of the Northeastern Santa Cruz Mountains and the Western Santa Clara Valley, California, from the SCSI-LR Seismic Survey

    USGS Publications Warehouse

    Catchings, R.D.; Goldman, M.R.; Gandhok, G.

    2006-01-01

    earthquakes sources. As one component of these joint studies, the U. S. Geological Survey acquired more than 28 km of combined seismic reflection/refraction data from the Santa Cruz Mountains to the central Santa Clara Valley in December 2000. The seismic investigation included both high-resolution (~5-m shot and sensor spacing) and relatively lower-resolution (~50-m sensor) seismic surveys from the central Santa Cruz Mountains to the central part of the valley. Collectively, we refer to these seismic investigations as the 2000 western Santa Clara Seismic Investigations (SCSI).

  17. M’zab Valley, Algeria

    NASA Image and Video Library

    2017-12-08

    NASA image acquired Feb. 9, 2011 Less than 5 percent of Algeria’s land surface is suitable for growing crops, and most precipitation falls on the Atlas Mountains along the coast. Inland, dust-laden winds blow over rocky plains and sand seas. However, in north central Algeria—off the tip of Grand Erg Occidental and about 450 kilometers (280 miles) south of Algiers—lies a serpentine stretch of vegetation. It is the M’zab Valley, filled with palm groves and dotted with centuries-old settlements. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite captured this image of M’zab Valley on February 9, 2011. ASTER combines infrared, red, and green wavelengths of light. Bare rock ranges in color from beige to peach. Buildings and paved surfaces appear gray. Vegetation is red, and brighter shades of red indicate more robust vegetation. This oasis results from water that is otherwise in short supply in the Sahara Desert, thanks to the valley’s approximately 3,000 wells. Chemical analysis of Algerian aquifers, as well studies of topography in Algeria and Tunisia, suggest this region experienced a cooler climate in the late Pleistocene, and potentially heavy monsoon rains earlier in the Holocene. The M’zab region shows evidence of meandering rivers and pinnate drainage patterns. The vegetation lining M’zab Valley highlights this old river valley’s contours. Cool summer temperatures and monsoon rains had long since retreated from the region by eleventh century, but this valley nevertheless supported the establishment of multiple fortified settlements, or ksours. Between 1012 A.D. and 1350 A.D., locals established the ksours of El-Atteuf, Bounoura, Melika, Ghardaïa, and Beni-Isguen. Collectively these cities are now a United Nations Educational, Scientific, and Cultural Organization (UNESCO) World Heritage site. NASA Earth Observatory image by Robert Simmon and Jesse Allen, using data from the GSFC

  18. Stream seepage and groundwater levels, Wood River Valley, south-central Idaho, 2012-13

    USGS Publications Warehouse

    Bartolino, James R.

    2014-01-01

    Stream discharge and water levels in wells were measured at multiple sites in the Wood River Valley, south-central Idaho, in August 2012, October 2012, and March 2013, as a component of data collection for a groundwater-flow model of the Wood River Valley aquifer system. This model is a cooperative and collaborative effort between the U.S. Geological Survey and the Idaho Department of Water Resources. Stream-discharge measurements for determination of seepage were made during several days on three occasions: August 27–28, 2012, October 22–24, 2012, and March 27–28, 2013. Discharge measurements were made at 49 sites in August and October, and 51 sites in March, on the Big Wood River, Silver Creek, their tributaries, and nearby canals. The Big Wood River generally gains flow between the Big Wood River near Ketchum streamgage (13135500) and the Big Wood River at Hailey streamgage (13139510), and loses flow between the Hailey streamgage and the Big Wood River at Stanton Crossing near Bellevue streamgage (13140800). Shorter reaches within these segments may differ in the direction or magnitude of seepage or may be indeterminate because of measurement uncertainty. Additional reaches were measured on Silver Creek, the North Fork Big Wood River, Warm Springs Creek, Trail Creek, and the East Fork Big Wood River. Discharge measurements also were made on the Hiawatha, Cove, District 45, Glendale, and Bypass Canals, and smaller tributaries to the Big Wood River and Silver Creek. Water levels in 93 wells completed in the Wood River Valley aquifer system were measured during October 22–24, 2012; these wells are part of a network established by the U.S. Geological Survey in 2006. Maps of the October 2012 water-table altitude in the unconfined aquifer and the potentiometric-surface altitude of the confined aquifer have similar topology to those on maps of October 2006 conditions. Between October 2006 and October 2012, water-table altitude in the unconfined aquifer rose by

  19. Foehn-induced effects on local dust pollution, frontal clouds and solar radiation in the Dead Sea valley

    NASA Astrophysics Data System (ADS)

    Kishcha, Pavel; Starobinets, Boris; Savir, Amit; Alpert, Pinhas; Kaplan, Michael

    2018-06-01

    Despite the long history of investigation of foehn phenomena, there are few studies of the influence of foehn winds on air pollution and none in the Dead Sea valley. For the first time the foehn phenomenon and its effects on local dust pollution, frontal cloudiness and surface solar radiation were analyzed in the Dead Sea valley, as it occurred on 22 March 2013. This was carried out using both numerical simulations and observations. The foehn winds intensified local dust emissions, while the foehn-induced temperature inversion trapped dust particles beneath this inversion. These two factors caused extreme surface dust concentration in the western Dead Sea valley. The dust pollution was transported by west winds eastward, to the central Dead Sea valley, where the speed of these winds sharply decreased. The transported dust was captured by the ascending airflow contributing to the maximum aerosol optical depth (AOD) over the central Dead Sea valley. On the day under study, the maximum surface dust concentration did not coincide with the maximum AOD: this being one of the specific effects of the foehn phenomenon on dust pollution in the Dead Sea valley. Radar data showed a passage of frontal cloudiness through the area of the Dead Sea valley leading to a sharp drop in noon solar radiation. The descending airflow over the downwind side of the Judean Mountains led to the formation of a cloud-free band followed by only the partial recovery of solar radiation because of the extreme dust pollution caused by foehn winds.

  20. Abundance and sexual size dimorphism of the giant gartersnake (Thamnophis gigas) in the Sacramento valley of California

    USGS Publications Warehouse

    Wylie, G.D.; Casazza, Michael L.; Gregory, C.J.; Halstead, B.J.

    2010-01-01

    The Giant Gartersnake (Thamnophis gigas) is restricted to wetlands of the Central Valley of California. Because of wetland loss in this region, the Giant Gartersnake is both federally and state listed as threatened. We conducted markrecapture studies of four populations of the Giant Gartersnake in the Sacramento Valley (northern Central Valley), California, to obtain baseline data on abundance and density to assist in recovery planning for this species. We sampled habitats that ranged from natural, unmanaged marsh to constructed managed marshes and habitats associated with rice agriculture. Giant Gartersnake density in a natural wetland (1.90 individuals/ha) was an order of magnitude greater than in a managed wetland subject to active season drying (0.17 individuals/ha). Sex ratios at all sites were not different from 1 1, and females were longer and heavier than males. Females had greater body condition than males, and individuals at the least disturbed sites had significantly greater body condition than individuals at the managed wetland. The few remaining natural wetlands in the Central Valley are important, productive habitat for the Giant Gartersnake, and should be conserved and protected. Wetlands constructed and restored for the Giant Gartersnake should be modeled after the permanent, shallow wetlands representative of historic Giant Gartersnake habitat. ?? 2010 Society for the Study of Amphibians and Reptiles.

  1. Fog and Haze in California's San Joaquin Valley

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This illustration features images of southern California and southwestern Nevada acquired on January 3, 2001 (Terra orbit 5569), and includes data from three of MISR's nine cameras. The San Joaquin Valley, which comprises the southern extent of California's Central Valley, covers much of the viewed area. Also visible are several of the Channel Islands near the bottom, and Mono and Walker Lakes, which stand out as darker patches near the top center, especially in the vertical and backward oblique images. Near the lower right of each image is the Los Angeles Basin, with the distinctive chevron shape of the Mojave Desert to its north.

    The Central Valley is a well-irrigated and richly productive agricultural area situated between the Coast Range and the snow-capped Sierra Nevadas. During the winter, the region is noted for its hazy overcasts and a low, thick ground fog known as the Tule. Owing to the effects of the atmosphere on reflected sunlight, dramatic differences in the MISR images are apparent as the angle of view changes. An area of thick, white fog in the San Joaquin Valley is visible in all three of the images. However, the pervasive haze that fills most of the valley is only slightly visible in the vertical view. At the oblique angles, the haze is highly distinguishable against the land surface background, particularly in the forward-viewing direction. Just above image center, the forward view also reveals bluish-tinged plumes near Lava Butte in Sequoia National Forest, where the National Interagency Coordination Center reported an active forest fire.

    The changing surface visibility in the multi-angle data allows us to derive the amount of atmospheric haze. In the lower right quadrant is a map of haze amount determined from automated processing of the MISR imagery. Low amounts of haze are shown in blue, and a variation in hue through shades of green, yellow, and red indicates progressively larger amounts of airborne particulates. Due to the

  2. Geology and water resources of Owens Valley, California

    USGS Publications Warehouse

    Hollett, Kenneth J.; Danskin, Wesley R.; McCaffrey, William F.; Walti, Caryl L.

    1991-01-01

    Owens Valley, a long, narrow valley located along the east flank of the Sierra Nevada in east-central California, is the main source of water for the city of Los Angeles. The city diverts most of the surface water in the valley into the Owens River-Los Angeles Aqueduct system, which transports the water more than 200 miles south to areas of distribution and use. Additionally, ground water is pumped or flows from wells to supplement the surface-water diversions to the river-aqueduct system. Pumpage from wells needed to supplement water export has increased since 1970, when a second aqueduct was put into service, and local concerns have been expressed that the increased pumpage may have had a detrimental effect on the environment and the indigenous alkaline scrub and meadow plant communities in the valley. The scrub and meadow communities depend on soil moisture derived from precipitation and the unconfined part of a multilayered aquifer system. This report, which describes the hydrogeology of the aquifer system and the water resources of the valley, is one in a series designed to (1) evaluate the effects that groundwater pumping has on scrub and meadow communities and (2) appraise alternative strategies to mitigate any adverse effects caused by, pumping. Two principal topographic features are the surface expression of the geologic framework--the high, prominent mountains on the east and west sides of the valley and the long, narrow intermountain valley floor. The mountains are composed of sedimentary, granitic, and metamorphic rocks, mantled in part by volcanic rocks as well as by glacial, talus, and fluvial deposits. The valley floor is underlain by valley fill that consists of unconsolidated to moderately consolidated alluvial fan, transition-zone, glacial and talus, and fluvial and lacustrine deposits. The valley fill also includes interlayered recent volcanic flows and pyroclastic rocks. The bedrock surface beneath the valley fill is a narrow, steep-sided graben

  3. Diablo Valley College: The First Forty Years, 1949-1989.

    ERIC Educational Resources Information Center

    Mahan, Don; And Others

    An overview is provided of the 40-year history of Diablo Valley College (DVC), examining the educational ideals of the founders of the college and the changes in the goals of community college education in Central Contra Costa County, California. Part 1 sets the historical scene for the establishment of public two-year colleges nationally, in…

  4. Comparison of Two Parametric Methods to Estimate Pesticide Mass Loads in California's Central Valley

    USGS Publications Warehouse

    Saleh, D.K.; Lorenz, D.L.; Domagalski, Joseph L.

    2011-01-01

    Mass loadings were calculated for four pesticides in two watersheds with different land uses in the Central Valley, California, by using two parametric models: (1) the Seasonal Wave model (SeaWave), in which a pulse signal is used to describe the annual cycle of pesticide occurrence in a stream, and (2) the Sine Wave model, in which first-order Fourier series sine and cosine terms are used to simulate seasonal mass loading patterns. The models were applied to data collected during water years 1997 through 2005. The pesticides modeled were carbaryl, diazinon, metolachlor, and molinate. Results from the two models show that the ability to capture seasonal variations in pesticide concentrations was affected by pesticide use patterns and the methods by which pesticides are transported to streams. Estimated seasonal loads compared well with results from previous studies for both models. Loads estimated by the two models did not differ significantly from each other, with the exceptions of carbaryl and molinate during the precipitation season, where loads were affected by application patterns and rainfall. However, in watersheds with variable and intermittent pesticide applications, the SeaWave model is more suitable for use on the basis of its robust capability of describing seasonal variation of pesticide concentrations. ?? 2010 American Water Resources Association. This article is a US Government work and is in the public domain in the USA.

  5. Data for ground-water test hole near Butte City, Central Valley aquifer project, California

    USGS Publications Warehouse

    French, James J.; Page, R.W.; Bertoldi, G.L.

    1983-01-01

    This report provides preliminary data for the third of seven test holes drilled as part of the Central Valley Aquifer Project which is part of the National Regional Aquifer Systems Analysis Program. The test hole was drilled in the SW 1/4 NE 1/4 sec. 32, T. 19 N., R. 1 W., Glenn County, California, about one-half mile south of the town of Butte City. Drilled to a depth of 1,432 feet below land surface, the hole is cased to a depth of 82 feet and equipped with three piezometer tubes to depths of 592 feet, 968 feet, and 1,330 feet. A 5-foot well screen is at the bottom of each piezometer. Each screened interval has a cement plug above and below it to isolate it from other parts of the aquifer , and the well bore is filled between the plugs with sediment. Nine cores and 49 sidewall cores were recovered. Laboratory tests were made for mineralogy, hydraulic conductivity, porosity , consolidation, grain-size distribution, Atterberg limits, X-ray diffraction, and chemical quality of water. Geophysical and thermal gradient logs were made. The hole is sampled periodically for chemical analysis and measured for water level in the three tapped zones. This report presents methods used to obtain field samples, laboratory procedures, and the data obtained. (USGS)

  6. An Integrated Hydrologic Model and Remote Sensing Synthesis Approach to Study Groundwater Extraction During a Historic Drought in the California Central Valley

    NASA Astrophysics Data System (ADS)

    Thatch, L. M.; Maxwell, R. M.; Gilbert, J. M.

    2017-12-01

    Over the past century, groundwater levels in California's San Joaquin Valley have dropped more than 30 meters in some areas due to excessive groundwater extraction to irrigate agricultural lands and feed a growing population. Between 2012 and 2016 California experienced the worst drought in its recorded history, further exacerbating this groundwater depletion. Due to lack of groundwater regulation, exact quantities of extracted groundwater in California are unknown and hard to quantify. We use a synthesis of integrated hydrologic model simulations and remote sensing products to quantify the impact of drought and groundwater pumping on the Central Valley water tables. The Parflow-CLM model was used to evaluate groundwater depletion in the San Joaquin River basin under multiple groundwater extraction scenarios simulated from pre-drought through recent drought years. Extraction scenarios included pre-development conditions, with no groundwater pumping; historical conditions based on decreasing groundwater level measurements; and estimated groundwater extraction rates calculated from the deficit between the predicted crop water demand, based on county land use surveys, and available surface water supplies. Results were compared to NASA's Gravity Recover and Climate Experiment (GRACE) data products to constrain water table decline from groundwater extraction during severe drought. This approach untangles various factors leading to groundwater depletion within the San Joaquin Valley both during drought and years of normal recharge to help evaluate which areas are most susceptible to groundwater overdraft, as well as further evaluating the spatially and temporally variable sustainable yield. Recent efforts to improve water management and ensure reliable water supplies are highlighted by California's Sustainable Groundwater Management Act (SGMA) which mandates Groundwater Sustainability Agencies to determine the maximum quantity of groundwater that can be withdrawn through

  7. Monitoring air quality in California's Central Valley with aircraft and continuous mountaintop observations - attribution insights gained by considering the scalar budget equation

    NASA Astrophysics Data System (ADS)

    Faloona, I. C.; Trousdell, J.; Caputi, D.; Conley, S. A.

    2017-12-01

    Ozone is one of the six criteria pollutants established by the US EPA's Clean Air Act, and one of two that still routinely violates federal standards as it is a secondary pollutant and therefore subject to indirect control strategies on complex, non-linear atmospheric chemistry. While improvements have been seen in many regions where ozone controls are in place, gains in California's San Joaquin Valley have lagged many other districts across the state. We present airborne measurements from several different campaigns in the valley (DISCOVER-AQ, ArvinO3, and CABOTS) along with data from a mountaintop monitoring site on its upwind side near the Pacific coast that has been operational for 5 years, and we shed light on several outstanding questions concerning air pollution in California's vast Central Valley. The framework of analysis is centered on the primitive equation of any atmospheric constituent - the scalar budget equation. By measuring each term in this equation, we gain insights into the relative impacts of exogenous (due to long range transport) vs. endogenous ozone (due to local photochemical production). We further argue that small aircraft campaigns with an emphasis on scalar budgeting sorties are a cost-effective tool in uncovering specific shortcomings of regional air quality models (e.g., lateral boundary conditions can be tested by comparing horizontal advection, turbulence parameterizations by comparing vertical fluxes, and chemical mechanisms by comparing net photochemical production rates.) In the case of NOx and CH4, for instance, we find that solving for surface emissions points toward inventory underestimates of both species by at least a factor of two. We discuss possible causes of these discrepancies, and suggest other ways to specifically vet aspects of regional air quality models with airborne measurements of meteorological and chemical variables.

  8. Birds of the St. Croix River valley: Minnesota and Wisconsin

    USGS Publications Warehouse

    Faanes, Craig A.

    1981-01-01

    The St. Croix River Valley encompasses nearly 11,550 km2 in east-central Minnesota and northwestern Wisconsin. A wide range of habitats are available for birds including upland oak, lowland deciduous, maple-basswood, lowland and upland coniferous forests, natural basin wetlands, and grasslands. Situated in the north-central region of the United States, the valley is a biological 'crossroads' for many species. Because of the mixed affinities of plant communities, the valley includes the northern and southern range limits for a number of species. Also, because the valley lies near the forest-prairie transition zone, many typical western breeding species (e.g. pintail, western meadowlark, yellow-headed blackbird) breed in proximity to typical eastern species such as tufted titmouse, eastern meadowlark, and cardinal. From 1966 to 1980, I conducted extensive surveys of avian distribution and abundance in the St. Croix River Valley. I have supplemented the results of these surveys with published and unpublished observations contributed by many ornithologists. These additional data include compilations from Christmas Bird Counts sponsored by the National Audubon Society and from the Breeding Bird Survey coordinated by the U.S. Fish and Wildlife Service. Three hundred fourteen species have been recorded in the study area; data are presented on the migration period, nesting season distribution, winter distribution, relative abundance, and habitat use of each species. Recognizing the uniqueness of the area, and its importance not only to wildlife but also to man, the U.S. Congress designated the St. Croix a National Scenic Riverway. This action provided a considerable degree of protection to lands along and directly adjacent to the river. Unfortunately, no similar legal measure exists to protect lands away from the river. With the exception of the northern quarter of the St. Croix River Valley, agricultural interests have made significant inroads into the habitat base. The

  9. Economic and Policy Drivers of Agricultural Water Desalination in California's Central Valley

    NASA Astrophysics Data System (ADS)

    Welle, P.; Medellin-Azuara, J.; Viers, J. H.; Mauter, M.

    2016-12-01

    Agriculture in arid regions is threatened by the twin stresses of soil salinity and uncertain water availability. Recently, water desalination has been a proposed solution for mitigating the effects of drought, soil salinization, and the ecological impacts of agricultural drainage. In this study, we combine data from earth observing systems with auxiliary information on prices, yields, and farmer behavior in order to create a decision framework which assesses the public and private costs and benefits of distributed desalination in the Central Valley (CV) of California. The use of remotely sensed crop classifiers allows us to resolve our analysis at the 30m pixel scale across the CV, a feature that allows us to characterize regional differences in technology effectiveness. We employ environmental and economic modeling to estimate the value of lower salinity irrigation water; the value of augmented water supply under present and future climate scenarios; and the human health, environmental, and climate change damages associated with generating power to desalinate water. We find that water desalination is only likely to be profitable in 4% of the CV during periods of severe drought, and that current costs would need to decrease by 70-90% for adoption to occur on the median acre. Fossil-fuel powered desalination technologies also generate air emissions that impose significant public costs in the form of human health and climate change damages, although these damages vary greatly depending on technology. The ecosystem service benefits of reduced agricultural drainage would need to be valued between 800 and 1200 per acre-foot, or nearly the full capital and operational costs of water desalination, for the net benefits of water desalination to be positive from a societal perspective.

  10. Integrated hazard assessment of Cirenmaco glacial lake in Zhangzangbo valley, Central Himalayas

    NASA Astrophysics Data System (ADS)

    Wang, Weicai; Gao, Yang; Iribarren Anacona, Pablo; Lei, Yanbin; Xiang, Yang; Zhang, Guoqing; Li, Shenghai; Lu, Anxin

    2018-04-01

    Glacial lake outburst floods (GLOFs) have recently become one of the primary natural hazards in the Himalayas. There is therefore an urgent need to assess GLOF hazards in the region. Cirenmaco, a moraine-dammed lake located in the upstream portion of Zhangzangbo valley, Central Himalayas, has received public attention after its damaging 1981 outburst flood. Here, by combining remote sensing methods, bathymetric survey and 2D hydraulic modeling, we assessed the hazard posed by Cirenmaco in its current status. Inter-annual variation of Cirenmaco lake area indicates a rapid lake expansion from 0.10 ± 0.08 km2 in 1988 to 0.39 ± 0.04 km2 in 2013. Bathymetric survey shows the maximum water depth of the lake in 2012 was 115 ± 2 m and the lake volume was calculated to be 1.8 × 107 m3. Field geomorphic analysis shows that Cirenmaco glacial lake is prone to GLOFs as mass movements and ice and snow avalanches can impact the lake and the melting of the dead ice in the moraine can lower the dam level. HEC-RAS 2D model was then used to simulate moraine dam failure of the Cirenmaco and assess GLOF impacts downstream. Reconstruction of Cirenmaco 1981 GLOF shows that HEC-RAS can produce reasonable flood extent and water depth, thus demonstrate its ability to effectively model complex GLOFs. GLOF modeling results presented can be used as a basis for the implementation of disaster prevention and mitigation measures. As a case study, this work shows how we can integrate different methods to GLOF hazard assessment.

  11. Modeling Land Application of Food-Processing Wastewater in the Central Valley, California

    NASA Astrophysics Data System (ADS)

    Rubin, Y.; Benito, P.; Miller, G.; McLaughlin, J.; Hou, Z.; Hermanowicz, S.; Mayer, U.

    2007-12-01

    California's Central Valley contains over 640 food-processing plants, serving a multi-billion dollar agricultural industry. These processors consume approximately 7.9 x 107 m3 of water per year. Approximately 80% of these processors discharge the resulting wastewater, which is typically high in organic matter, nitrogen, and salts, to land, and many of these use land application as a treatment method. Initial investigations revealed elevated salinity levels to be the most common form of groundwater degradation near land application sites, followed by concentrations of nitrogen compounds, namely ammonia and nitrate. Enforcement actions have been taken against multiple food processors, and the regulatory boards have begun to re-examine the land disposal permitting process. This paper summarizes a study that was commissioned in support of these actions. The study has multiple components which will be reviewed briefly, including: (1) characterization of the food-processing related waste stream; (2) fate and transport of the effluent waste stream in the unsaturated zone at the land application sites; (3) fate and transport of the effluent waste stream at the regional scale; (4) predictive uncertainty due to spatial variability and data scarcity at the land application sites and at the regional scale; (5) problem mitigation through off-site and in-situ actions; (6) long-term solutions. The emphasis of the talk will be placed on presenting and demonstrating a stochastic framework for modeling the transport and attenuation of these wastes in the vadose zone and in the saturated zone, and the related site characterization needs, as affected by site conditions, water table depth, waste water application rate, and waste constituent concentrations.

  12. 77 FR 33237 - Saline Valley Warm Springs Management Plan/Environmental Impact Statement, Death Valley National...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-05

    ... Valley Warm Springs Management Plan/Environmental Impact Statement, Death Valley National Park, Inyo... an Environmental Impact Statement for the Saline Valley Warm Springs Management Plan, Death Valley... analysis process for the Saline Valley Warm Springs Management Plan for Death Valley [[Page 33238...

  13. Geologic map of the upper Arkansas River valley region, north-central Colorado

    USGS Publications Warehouse

    Kellogg, Karl S.; Shroba, Ralph R.; Ruleman, Chester A.; Bohannon, Robert G.; McIntosh, William C.; Premo, Wayne R.; Cosca, Michael A.; Moscati, Richard J.; Brandt, Theodore R.

    2017-11-17

    This 1:50,000-scale U.S. Geological Survey geologic map represents a compilation of the most recent geologic studies of the upper Arkansas River valley between Leadville and Salida, Colorado. The valley is structurally controlled by an extensional fault system that forms part of the prominent northern Rio Grande rift, an intra-continental region of crustal extension. This report also incorporates new detailed geologic mapping of previously poorly understood areas within the map area and reinterprets previously studied areas. The mapped region extends into the Proterozoic metamorphic and intrusive rocks in the Sawatch Range west of the valley and the Mosquito Range to the east. Paleozoic rocks are preserved along the crest of the Mosquito Range, but most of them have been eroded from the Sawatch Range. Numerous new isotopic ages better constrain the timing of both Proterozoic intrusive events, Late Cretaceous to early Tertiary intrusive events, and Eocene and Miocene volcanic episodes, including widespread ignimbrite eruptions. The uranium-lead ages document extensive about 1,440-million years (Ma) granitic plutonism mostly north of Buena Vista that produced batholiths that intruded an older suite of about 1,760-Ma metamorphic rocks and about 1,700-Ma plutonic rocks. As a result of extension during the Neogene and possibly latest Paleogene, the graben underlying the valley is filled with thick basin-fill deposits (Dry Union Formation and older sediments), which occupy two sub-basins separated by a bedrock high near the town of Granite. The Dry Union Formation has undergone deep erosion since the late Miocene or early Pliocene. During the Pleistocene, ongoing steam incision by the Arkansas River and its major tributaries has been interrupted by periodic aggradation. From Leadville south to Salida as many as seven mapped alluvial depositional units, which range in age from early to late Pleistocene, record periodic aggradational events along these streams that are

  14. Geophysical studies in the vicinity of Blue Mountain and Pumpernickel Valley near Winnemucca, north-central Nevada

    USGS Publications Warehouse

    Ponce, David A.

    2012-01-01

    From May 2008 to September 2009, the U.S. Geological Survey (USGS) collected data from more than 660 gravity stations, 100 line-km of truck-towed magnetometer traverses, and 260 physical-property sites in the vicinity of Blue Mountain and Pumpernickel Valley, northern Nevada (fig. 1). Gravity, magnetic, and physical-property data were collected to study regional crustal structures as an aid to understanding the geologic framework of the Blue Mountain and Pumpernickel Valley areas, which in general, have implications for mineral- and geothermal-resource investigations throughout the Great Basin.

  15. 27 CFR 9.57 - Green Valley of Russian River Valley.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Green Valley of Russian River Valley. 9.57 Section 9.57 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.57 Green Valley of Russian River...

  16. 27 CFR 9.57 - Green Valley of Russian River Valley.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Green Valley of Russian River Valley. 9.57 Section 9.57 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.57 Green Valley of Russian River...

  17. 27 CFR 9.57 - Green Valley of Russian River Valley.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Green Valley of Russian River Valley. 9.57 Section 9.57 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.57 Green Valley of Russian River...

  18. 27 CFR 9.57 - Green Valley of Russian River Valley.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Green Valley of Russian River Valley. 9.57 Section 9.57 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.57 Green Valley of Russian River...

  19. 27 CFR 9.57 - Green Valley of Russian River Valley.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Green Valley of Russian River Valley. 9.57 Section 9.57 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.57 Green Valley of Russian River...

  20. Climate controls on valley fever incidence in Kern County, California

    NASA Astrophysics Data System (ADS)

    Zender, Charles S.; Talamantes, Jorge

    2006-01-01

    Coccidiodomycosis (valley fever) is a systemic infection caused by inhalation of airborne spores from Coccidioides immitis, a soil-dwelling fungus found in the southwestern United States, parts of Mexico, and Central and South America. Dust storms help disperse C. immitis so risk factors for valley fever include conditions favorable for fungal growth (moist, warm soil) and for aeolian soil erosion (dry soil and strong winds). Here, we analyze and inter-compare the seasonal and inter-annual behavior of valley fever incidence and climate risk factors for the period 1980-2002 in Kern County, California, the US county with highest reported incidence. We find weak but statistically significant links between disease incidence and antecedent climate conditions. Precipitation anomalies 8 and 20 months antecedent explain only up to 4% of monthly variability in subsequent valley fever incidence during the 23 year period tested. This is consistent with previous studies suggesting that C. immitis tolerates hot, dry periods better than competing soil organisms and, as a result, thrives during wet periods following droughts. Furthermore, the relatively small correlation with climate suggests that the causes of valley fever in Kern County could be largely anthropogenic. Seasonal climate predictors of valley fever in Kern County are similar to, but much weaker than, those in Arizona, where previous studies find precipitation explains up to 75% of incidence. Causes for this discrepancy are not yet understood. Higher resolution temporal and spatial monitoring of soil conditions could improve our understanding of climatic antecedents of severe epidemics.

  1. Global positioning system surveying to monitor land subsidence in Sacramento Valley, California, USA

    USGS Publications Warehouse

    Ikehara, M.E.

    1994-01-01

    A subsidence research program began in 1985 to document the extent and magnitude of land subsidence in Sacramento Valley, California, an area of about 15 600 km2m, using Global Positioning System (GPS) surveying. In addition to periodic conventional spirit levelling, an examination was made of the changes in GPS-derived ellipsoidal height differences (summary differences) between pairs of adjacent bench marks in central Sacramento Valley from 1986 to 1989. The average rates of land subsidence in the southern Sacramento Valley for the past several decades were determined by comparing GPS-derived orthometric heights with historic published elevations. A maximum average rate of 0.053 m year-1 (0.90 m in 17 years) of subsidence has been measured. -Author

  2. Morphology of large valleys on Hawaii - Evidence for groundwater sapping and comparisons with Martian valleys

    NASA Technical Reports Server (NTRS)

    Kochel, R. Craig; Piper, Jonathan F.

    1986-01-01

    Morphometric data on the runoff and sapping valleys on the slopes of Hawaii and Molokai in Hawaii are analyzed. The analysis reveals a clear distinction between the runoff valleys and sapping valleys. The Hawaiian sapping valleys are characterized by: (1) steep valley walls and flat floors, (2) amphitheater heads, (3) low drainage density, (4) paucity of downstream tributaries, (5) low frequency of up-dip tributaries, and (6) structural and stratigraphic control on valley patterns. The characteristics of the Hawaiian sapping valleys are compared to Martian valleys and experimental systems, and good correlation between the data is detected. Flume experiments were also conducted to study the evolution of sapping valleys in response to variable structure and stratigraphy.

  3. Extent and timing of paleoglaciation in the Kanas Valley, Altai Mountains, China, based on remote sensing, field investigations and multiple dating methods

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Harbor, Jon; Cui, Zhijiu; Liu, Liang; Liu, Beibei; Fu, Yanjing; Shi, Yuanhuang; Gribenski, Natacha; Blomdin, Robin; Stroeven, Arjen; Caffee, Marc; Jansson, Krister

    2014-05-01

    Reconstructions of the timing and extent of past glaciation provide key constraints for paleoclimate and numerical modeling of past glacier behavior. As part of the multinational Central Asian Paleoglaciology Project we are reconstructing the timing and extent of past glaciation along and across a series of mountain ranges in central Asia using consistent methods for mapping, field investigations and numerical dating. Here we report on new findings for the Kanas Valley in northwest China, a large glaciated valley system on the south side of the Altai Mountains. Previous studies have concluded that the Kanas Valley has been shaped by a series of major glacial advances that produced overdeepened basins, a U-shaped valley cross profile, and extensive glacial and glaciofluvial deposits. Existing Optically Stimulated Luminescence (OSL) and Electron Spin Resonance (ESR) dating results suggest major glaciation in the Kanas Valley during Marine Oxygen Isotope Stages (MIS) 3, 5, and 6, but very limited MIS 2 glaciation. Limited MIS 2 glaciation has also been suggested for other parts of central Asia, and this contrasts with extensive MIS 2 glaciation in Europe and North America. Field studies in 2013 provided new evidence for the highest elevation extent of glaciation in the Kanas Valley in the vicinity of the 20-km long Lake Kanas, with the upper limit of distinct erratics on the valley sidewalls indicating past ice thicknesses here up to 1000 m. Upper limits of erratics extending from Lake Kanas to the mapped maximum down-valley extent of glaciation suggest an ice surface slope of 1.8 degrees for the lower half of the paleoglacier in the Kanas Valley, assuming that all the erratics were deposited at the same time. Systematic sampling of glacial erratics, basal till, terminal moraines, glacially eroded bedrock, and glaciofluvial deposits provided material that is being used for cosmogenic radionuclide, OSL and ESR dating of the glacial chronology, and for dating

  4. Groundwater Quality, Age, and Probability of Contamination, Eagle River Watershed Valley-Fill Aquifer, North-Central Colorado, 2006-2007

    USGS Publications Warehouse

    Rupert, Michael G.; Plummer, Niel

    2009-01-01

    The Eagle River watershed is located near the destination resort town of Vail, Colorado. The area has a fastgrowing permanent population, and the resort industry is rapidly expanding. A large percentage of the land undergoing development to support that growth overlies the Eagle River watershed valley-fill aquifer (ERWVFA), which likely has a high predisposition to groundwater contamination. As development continues, local organizations need tools to evaluate potential land-development effects on ground- and surface-water resources so that informed land-use and water management decisions can be made. To help develop these tools, the U.S. Geological Survey (USGS), in cooperation with Eagle County, the Eagle River Water and Sanitation District, the Town of Eagle, the Town of Gypsum, and the Upper Eagle Regional Water Authority, conducted a study in 2006-2007 of the groundwater quality, age, and probability of contamination in the ERWVFA, north-central Colorado. Ground- and surface-water quality samples were analyzed for major ions, nutrients, stable isotopes of hydrogen and oxygen in water, tritium, dissolved gases, chlorofluorocarbons (CFCs), and volatile organic compounds (VOCs) determined with very low-level laboratory methods. The major-ion data indicate that groundwaters in the ERWVFA can be classified into two major groups: groundwater that was recharged by infiltration of surface water, and groundwater that had less immediate recharge from surface water and had elevated sulfate concentrations. Sulfate concentrations exceeded the USEPA National Secondary Drinking Water Regulations (250 milligrams per liter) in many wells near Eagle, Gypsum, and Dotsero. The predominant source of sulfate to groundwater in the Eagle River watershed is the Eagle Valley Evaporite, which is a gypsum deposit of Pennsylvanian age located predominantly in the western one-half of Eagle County.

  5. Potential impact of lava flows on regional water supplies: case study of central Oregon Cascades volcanism and the Willamette Valley, USA

    NASA Astrophysics Data System (ADS)

    Deligne, Natalia; Cashman, Katharine; Grant, Gordon; Jefferson, Anne

    2013-04-01

    Lava flows are often considered to be natural hazards with localized bimodal impact - they completely destroy everything in their path, but apart from the occasional forest fire, cause little or no damage outside their immediate footprint. However, in certain settings, lava flows can have surprising far reaching impacts with the potential to cause serious problems in distant urban areas. Here we present results from a study of the interaction between lava flows and surface water in the central Oregon Cascades, USA, where we find that lava flows in the High Cascades have the potential to cause considerable water shortages in Eugene, Oregon (Oregon's second largest metropolitan area) and the greater Willamette Valley (home to ~70% of Oregon's population). The High Cascades host a groundwater dominated hydrological regime with water residence times on the order of years. Due to the steady output of groundwater, rivers sourced in the High Cascades are a critical water resource for Oregon, particularly in August and September when it has not rained for several months. One such river, the McKenzie River, is the sole source of drinking water for Eugene, Oregon, and prior to the installation of dams in the 1960s accounted for ~40% of late summer river flow in the Willamette River in Portland, 445 river km downstream of the source of the McKenzie River. The McKenzie River has been dammed at least twice by lava flows during the Holocene; depending the time of year that these eruptions occurred, we project that available water would have decreased by 20% in present-day Eugene, Oregon, for days to weeks at a time. Given the importance of the McKenzie River and its location on the margin of an active volcanic area, we expect that future volcanic eruptions could likewise impact water supplies in Eugene and the greater Willamette Valley. As such, the urban center of Eugene, Oregon, and also the greater Willamette Valley, is vulnerable to the most benign of volcanic hazards, lava

  6. Rift Valley Fever Outbreak in Livestock in Kenya, 2006–2007

    PubMed Central

    Munyua, Peninah; Murithi, Rees M.; Wainwright, Sherrilyn; Githinji, Jane; Hightower, Allen; Mutonga, David; Macharia, Joseph; Ithondeka, Peter M.; Musaa, Joseph; Breiman, Robert F.; Bloland, Peter; Njenga, M. Kariuki

    2010-01-01

    We analyzed the extent of livestock involvement in the latest Rift Valley fever (RVF) outbreak in Kenya that started in December 2006 and continued until June 2007. When compared with previous RVF outbreaks in the country, the 2006–07 outbreak was the most extensive in cattle, sheep, goats, and camels affecting thousands of animals in 29 of 69 administrative districts across six of the eight provinces. This contrasted with the distribution of approximately 700 human RVF cases in the country, where over 85% of these cases were located in four districts; Garissa and Ijara districts in Northeastern Province, Baringo district in Rift Valley Province, and Kilifi district in Coast Province. Analysis of livestock and human data suggests that livestock infections occur before virus detection in humans, as supported by clustering of human RVF cases around livestock cases in Baringo district. The highest livestock morbidity and mortality rates were recorded in Garissa and Baringo districts, the same districts that recorded a high number of human cases. The districts that reported RVF in livestock for the first time in 2006/07 included Kitui, Tharaka, Meru South, Meru central, Mwingi, Embu, and Mbeere in Eastern Province, Malindi and Taita taveta in Coast Province, Kirinyaga and Murang'a in Central Province, and Baringo and Samburu in Rift Valley Province, indicating that the disease was occurring in new regions in the country. PMID:20682907

  7. [Genetic composition of Chilean population: rural communities of Elqui, Limari and Choapa valleys].

    PubMed

    Acuña, M; Llop, E; Rothhammer, F

    2000-06-01

    The population that inhabits the semiarid Northern zone of Chile arose from ethnic admixture between aborigines, Spanish conquerors and the influx, during the XVII century, of foreign aboriginal workers and a minority of African slaves. To study the phenotypic frequencies of 15 genetic markers among populations inhabiting valleys in the Northern zone of Chile and to estimate the percentage of indigenous, African and Caucasian admixture in these populations. Throughout five different field works, blood samples were obtained from 120 individuals living in the Elqui valley, 120 individuals living in the Limari valley and 85 living in the Choapa valley. Blood groups, erythrocyte enzymes, plasma proteins and HLA markers were typified. In the populations studied, the contribution of non indigenous genes was low in relation with the time elapsed since the Spanish invasion. The Hardy-Weinberg disequilibrium for MNS system would have microevolutive implications. The admixture percentages in these valleys confirm ethnic and historic information. The variation of the enzyme esterase D is identical to that of other Chilean populations. The phenotypic and genetic frequencies in the three populations studied and different admixture of indigenous genes is inversely proportional to the geographic distance from Santiago, in Central Chile.

  8. Groundwater quality in the shallow aquifers of the Monterey Bay, Salinas Valley, and adjacent highland areas, Southern Coast Ranges, California

    USGS Publications Warehouse

    Burton, Carmen

    2018-05-30

    The Monterey-Salinas Shallow Aquifer study unit covers approximately 7,820 square kilometers (km2) in Santa Cruz, Monterey, and San Luis Obispo Counties in the Central Coast Hydrologic Region of California. The study unit was divided into four study areas—Santa Cruz, Pajaro Valley, Salinas Valley, and Highlands. More than 75 percent of the water used for drinking-water supply in the Central Coast Hydrologic Region of California is groundwater, and there are more than 8,000 well driller’s logs for domestic wells (California Department of Water Resources, 2013).

  9. Groundwater Quality in the Shallow Aquifers of the Monterey Bay, Salinas Valley, and Adjacent Highland Areas, Southern Coast Ranges, California

    USGS Publications Warehouse

    Burton, Carmen

    2018-05-30

    The Monterey-Salinas Shallow Aquifer study unit covers approximately 7,820 square kilometers (km2) in Santa Cruz, Monterey, and San Luis Obispo Counties in the Central Coast Hydrologic Region of California. The study unit was divided into four study areas—Santa Cruz, Pajaro Valley, Salinas Valley, and Highlands. More than 75 percent of the water used for drinking-water supply in the Central Coast Hydrologic Region of California is groundwater, and there are more than 8,000 well driller’s logs for domestic wells (California Department of Water Resources, 2013).

  10. Hydrogeology of a drift-filled bedrock valley near Lino Lakes, Anoka County, Minnesota

    USGS Publications Warehouse

    Winter, T.C.; Pfannkuch, H.O.

    1976-01-01

    The bedrock surface of east-central Minnesota is dissected by an intricate network of valleys. Outside the bedrock valley at site B, 3 mi (4. 8 km) from site A, 100 ft (30 m) of drift overlies the bedrock surface. Observation wells were installed at the two sites to determine the vertical ground-water movement between the various aquifer units and the lateral movement between the two sites. An aquifer test of the lowest valley-fill aquifer at site A showed that the observation well completed in the same aquifer as the pumping well responded immediately; whereas a lag of about 100 min occurred between the lower valley fill and uppermost body of sand and gravel. This indicates that the hydraulic connection between these two layers is poor at the immediate site. Test results show that the lower sand-and-gravel aquifer has a transmissivity between 14,000 and 27,000 ft2/d (1,300 and 2,500 m2/d). Although the hydraulic gradient is vertically downward in the valley, much of the drift fill is poorly permeable. This suggests that the quantity of downward-percolating water reaching the lowest valley-fill aquifer is relatively small at the test site. Because valley cut through a number of bedrock aquifers in the region, they could potentially be an important avenue of contamination from land-surface waste. In addition, the vast network of bedrock valleys in the Twin Cities area might cause contaminants to disseminate rather rapidly throughout a large area.

  11. The cultural and chronological context of early Holocene maize and squash domestication in the Central Balsas River Valley, Mexico

    PubMed Central

    Ranere, Anthony J.; Piperno, Dolores R.; Holst, Irene; Dickau, Ruth; Iriarte, José

    2009-01-01

    Molecular evidence indicates that the wild ancestor of maize is presently native to the seasonally dry tropical forest of the Central Balsas watershed in southwestern Mexico. We report here on archaeological investigations in a region of the Central Balsas located near the Iguala Valley in Guerrero state that show for the first time a long sequence of human occupation and plant exploitation reaching back to the early Holocene. One of the sites excavated, the Xihuatoxtla Shelter, contains well-stratified deposits and a stone tool assemblage of bifacially flaked points, simple flake tools, and numerous handstones and milling stone bases radiocarbon dated to at least 8700 calendrical years B.P. As reported in a companion paper (Piperno DR, et al., in this issue of PNAS), starch grain and phytolith residues from the ground and chipped stone tools, plus phytoliths from directly associated sediments, provide evidence for maize (Zea mays L.) and domesticated squash (Cucurbita spp.) in contexts contemporaneous with and stratigraphically below the 8700 calendrical years B.P. date. The radiocarbon determinations, stratigraphic integrity of Xihuatoxtla's deposits, and characteristics of the stone tool assemblages associated with the maize and squash remains all indicate that these plants were early Holocene domesticates. Early agriculture in this region of Mexico appears to have involved small groups of cultivators who were shifting their settlements seasonally and engaging in a variety of subsistence pursuits. PMID:19307573

  12. Ground-water conditions in Avra Valley, Pima and Pinal Counties, Arizona -1985

    USGS Publications Warehouse

    Cuff, Melinda K.; Anderson, S.R.

    1987-01-01

    Avra Valley is a north-trending alluvial basin about 15 mi west of Tucson in Pima and Pinal Counties in south-central Arizona. The valley includes about 520 sq mi of which about 100 sq mi is in the San Xavier Indian Reservation. The basin is bounded on the east by the Tortolita, Tucson, and Sierrita Mountains and on the west by the Picacho, Silverbell, and Roskruge Mountains. The climate of the valley is semiarid, the average annual precipitation ranges from 8 to 12 in., and the average annual lake evaporation ranges from 58 to 62 in. Two major ephemeral streams--Santa Cruz River and Brawley Wash--drain the area. Santa Cruz River and Brawley Wash and their tributaries provide a source of recharge to an extensive alluvial aquifer that underlies the valley floor. Since 1940, the amount of groundwater pumped from the aquifer has been greater than the amount of natural recharge from infiltration and underflow. Overdraft of the aquifer resulted in substantial water level declines throughout the valley. Until 1969, use of groundwater in Avra Valley was for irrigation. Since 1969, the city of Tucson has pumped and transported groundwater for municipal use in the adjacent Tucson basin from lands that were purchased and retired from agriculture. The purpose of this report is to describe groundwater conditions in Avra Valley as of 1985. A brief discussion of the geohydrologic setting and history of groundwater development are given to define aquifer characteristics, changes in groundwater levels, and groundwater pumpage since 1940. (Lantz-PTT)

  13. Geological literature on the San Joaquin Valley of California

    USGS Publications Warehouse

    Maher, J.C.; Trollman, W.M.; Denman, J.M.

    1973-01-01

    The following list of references includes most of the geological literature on the San Joaquin Valley and vicinity in central California (see figure 1) published prior to January 1, 1973. The San Joaquin Valley comprises all or parts of 11 counties -- Alameda, Calaveras, Contra Costa, Fresno, Kern, Kings, Madera, Merced, San Joaquin, Stanislaus, and Tulare (figure 2). As a matter of convenient geographical classification the boundaries of the report area have been drawn along county lines, and to include San Benito and Santa Clara Counties on the west and Mariposa and Tuolumne Counties on the east. Therefore, this list of geological literature includes some publications on the Diablo and Temblor Ranges on the west, the Tehachapi Mountains and Mojave Desert on the south, and the Sierra Nevada Foothills and Mountains on the east.

  14. Valley Fever (Coccidioidomycosis) Statistics

    MedlinePlus

    ... Valley fever may be under-recognized. 2 , 3 Public health surveillance for Valley fever Valley fever is reportable ... MMWR) . Check with your local, state, or territorial public health department for more information about disease reporting requirements ...

  15. Pumpernickel Valley Geothermal Project Thermal Gradient Wells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Z. Adam Szybinski

    2006-01-01

    The Pumpernickel Valley geothermal project area is located near the eastern edge of the Sonoma Range and is positioned within the structurally complex Winnemucca fold and thrust belt of north-central Nevada. A series of approximately north-northeast-striking faults related to the Basin and Range tectonics are superimposed on the earlier structures within the project area, and are responsible for the final overall geometry and distribution of the pre-existing structural features on the property. Two of these faults, the Pumpernickel Valley fault and Edna Mountain fault, are range-bounding and display numerous characteristics typical of strike-slip fault systems. These characteristics, when combined withmore » geophysical data from Shore (2005), indicate the presence of a pull-apart basin, formed within the releasing bend of the Pumpernickel Valley – Edna Mountain fault system. A substantial body of evidence exists, in the form of available geothermal, geological and geophysical information, to suggest that the property and the pull-apart basin host a structurally controlled, extensive geothermal field. The most evident manifestations of the geothermal activity in the valley are two areas with hot springs, seepages, and wet ground/vegetation anomalies near the Pumpernickel Valley fault, which indicate that the fault focuses the fluid up-flow. There has not been any geothermal production from the Pumpernickel Valley area, but it was the focus of a limited exploration effort by Magma Power Company. In 1974, the company drilled one exploration/temperature gradient borehole east of the Pumpernickel Valley fault and recorded a thermal gradient of 160oC/km. The 1982 temperature data from five unrelated mineral exploration holes to the north of the Magma well indicated geothermal gradients in a range from 66 to 249oC/km for wells west of the fault, and ~283oC/km in a well next to the fault. In 2005, Nevada Geothermal Power Company drilled four geothermal gradient wells

  16. Chapter 2: Beginning of water studies in the Central Arizona Highlands

    Treesearch

    Gerald J. Gottfried; Leonard F. DeBano; Malchus B. Baker

    1999-01-01

    Water has been recognized as an important resource in central Arizona and has affected populations occupying the Salt River Valley for centuries. Water related activities have been documented since about 200 before the common era, when Hohokam Indians settled the Valley and constructed canals to irrigate their fields. Europeans began to settle in the Phoenix area in...

  17. Valley polarization in bismuth

    NASA Astrophysics Data System (ADS)

    Fauque, Benoit

    2013-03-01

    The electronic structure of certain crystal lattices can contain multiple degenerate valleys for their charge carriers to occupy. The principal challenge in the development of valleytronics is to lift the valley degeneracy of charge carriers in a controlled way. In bulk semi-metallic bismuth, the Fermi surface includes three cigar-shaped electron valleys lying almost perpendicular to the high symmetry axis known as the trigonal axis. The in-plane mass anisotropy of each valley exceeds 200 as a consequence of Dirac dispersion, which drastically reduces the effective mass along two out of the three orientations. According to our recent study of angle-dependent magnetoresistance in bismuth, a flow of Dirac electrons along the trigonal axis is extremely sensitive to the orientation of in-plane magnetic field. Thus, a rotatable magnetic field can be used as a valley valve to tune the contribution of each valley to the total conductivity. As a consequence of a unique combination of high mobility and extreme mass anisotropy in bismuth, the effect is visible even at room temperature in a magnetic field of 1 T. Thus, a modest magnetic field can be used as a valley valve in bismuth. The results of our recent investigation of angle-dependent magnetoresistance in other semi-metals and doped semiconductors suggest that a rotating magnetic field can behave as a valley valve in a multi-valley system with sizeable mass anisotropy.

  18. Valley dynamics of intravalley and intervalley multiexcitonic states in monolayer WS2

    NASA Astrophysics Data System (ADS)

    Fu, Jiyong; Bezerra, Andre; Qu, Fanyao

    2018-03-01

    We present a comprehensive model comprising of a complete set of rate equations, which account for charge transfer among multiexcitonic channels including excitons, trions, and biexcitons, to investigate valley (locked with spin) dynamics in monolayer WS2. The steady-state photoluminescence (PL) spectra, underlying the laser power dependence of excitonic populations, are also determined. Our computed PL for all excitonic states agrees with the experimental data of Paradisanos et al. [Appl. Phys. Lett. 110, 193102 (2017), 10.1063/1.4983285]. We find that the relative weight of PL, stemmed from different excitonic channels, strongly depends on the laser power even under dynamical conditions. Remarkably, the biexciton channel, having the weakest PL intensity at low laser powers, tends to prevail in PL over other excitonic states as the power strengthens. In addition, by accounting for intervalley scatterings, which enable transfer of excitonic states from one valley to the other, we determine the valley polarization, which strongly depends on intervalley scatterings and the exciton generation rates in the two valleys. On the other hand, the valley polarization for all excitonic channels is found almost independent of the laser power, consistent with experimental measurements as well. Finally, the valley dynamics involving both intra- and intervalley trions is discussed. Our model and numerical outcome should be beneficial to experiments especially featuring the interplay of multiexcitonic channels in, e.g., elucidating experimental data, estimating central excitonic quantities including recombination times and transition rates, and in widening possible new experimental scopes.

  19. Alumina+Silica+/-Germanium Alteration in Smectite-Bearing Marathon Valley, Endeavour Crater Rim, Mars

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, D. W.; Gellert, R.; Van Bommel, S.; Arvidson, R. E.; Clark, B. C.; Ming, D. W.; Schroeder, C.; Yen, A. S.; Fox, V. K.; Farrand, W. H.; hide

    2016-01-01

    Mars Exploration Rover Opportunity has been exploring Mars for 12+ years, and is presently investigating the geology of a western rim segment of 22 kilometers diameter, Noachian- aged Endeavour crater. The Alpha Particle X-ray Spectrometer has determined the compositions of a pre-impact lithology, the Matijevic fm., and polymict impact breccias ejected from the crater, the Shoemaker fm. Opportunity is now investigating a region named Marathon Valley that cuts southwest-northeast through the central portion of the rim segment and provides a window into the lower stratigraphic record. (Geographic names used here are informal.) At the head of Marathon Valley, referred to here as Upper Marathon Valley, is a shallow, ovoid depression approximately 25×35 millimeters in size, named Spirit of Saint Louis. Layering inside Spirit of Saint Louis appears continuous with the Upper Marathon Valley rocks outside, indicating they are coeval. Spirit of Saint Louis is partly bounded by approximately 10-20 centimeters wide zone containing reddish altered rocks (red zone). Red zones also form prominent curvilinear features in Marathon Valley. Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) spectra provide evidence for a really extensive Fe-Mg smectite in the Marathon Valley region, indicating distinct styles of aqueous alteration. The CRISM detections of smectites are based on metal-OH absorptions at approximately 2.3 and 2.4 micron that are at least two times the background noise level.

  20. Wind's Marks in "Perseverance Valley" (Enhanced Color)

    NASA Image and Video Library

    2017-12-06

    This patch of rocky Martian ground on the floor of "Perseverance Valley" on the inner slope of the western rim of Endurance Crater slopes steeply downhill from left to right. Some textures seen here, including striations just above and parallel to the edge of a solar panel at far left, may be due to abrasion by wind-driven sand. Researchers interpret them as possible signs of past winds blowing from right to left, up and out of the crater, which currently hosts sand dunes on its central floor. The view spans about 11.5 feet (3.5 meters) from left to right and is presented in enhanced color to make differences in surface materials easier to see. The Panoramic Camera (Pancam) on NASA's Mars Exploration Rover Opportunity took the component images of this scene during the period Oct. 13 through Oct. 20, 2017, corresponding to sols (Martian days) 4878 through 4884 of the rover's work on Mars. Opportunity entered the upper end of Perseverance Valley in July 2017 for several months of investigating how it formed. The valley is a system of shallow troughs extending about the length of two football fields down the crater rim's steep inner slope. Endurance Crater is about 14 miles (22 kilometers) in diameter. Opportunity has been exploring features on its western rim since 2011, after investigating a series of smaller craters beginning with the one it landed in on Jan. 25, 2004, Universal Time (Jan. 24, PST). The origin of Perseverance Valley is unknown, but some observed features suggest that water might have played a role in the past. Opportunity is descending the steep valley, making observations along the way that could help illuminate the origin of this feature. The bedrock target area in this view is called "La Bajada." The image combines exposures taken through three Pancam filters, centered at wavelengths of 753 nanometers (near-infrared), 535 nanometers (green) and 432 nanometers (violet). https://photojournal.jpl.nasa.gov/catalog/PIA22072

  1. How much groundwater did California's Central Valley lose during the 2012-2016 drought?

    NASA Astrophysics Data System (ADS)

    Xiao, Mu; Koppa, Akash; Mekonnen, Zelalem; Pagán, Brianna R.; Zhan, Shengan; Cao, Qian; Aierken, Abureli; Lee, Hyongki; Lettenmaier, Dennis P.

    2017-05-01

    We estimate net groundwater storage change in the Central Valley from April 2002 to September 2016 as the difference between inflows and outflows, precipitation, evapotranspiration, and changes in soil moisture and surface water storage. We also estimate total water storage change attributable to groundwater change using Gravity Recovery and Climate Experiment (GRACE) satellite data, which should be equivalent to our water balance estimates. Over two drought periods within our 14-1/2 years study period (January 2007 to December 2009 and October 2012 to September 2016), we estimate from our water balance that a total of 16.5 km3 and 40.0 km3 of groundwater was lost, respectively. Our water balance-based estimate of the overall groundwater loss over the 14-1/2 years is -20.7 km3, which includes substantial recovery during nondrought periods The estimated rate of groundwater loss is greater during the recent drought (10.0 ± 0.2 versus 5.5 ± 0.3 km3/yr) than in the 2007-2009 drought, due to lower net inflows, a transition from row crops to trees, and higher crop water use, notwithstanding a reduction in irrigated area. The GRACE estimates of groundwater loss (-5.0 km3/yr for both water balance and GRACE during 2007-2009, and -11.2 km3/yr for GRACE versus -10 km3/yr for water balance during 2012-2016) are quite consistent for the two methods. However, over the entire study period, the GRACE-based groundwater loss estimate is almost triple that from the water balance, mostly because GRACE does not indicate the between-drought groundwater recovery that is inferred from our water balance.

  2. Statistical modeling of valley fever data in Kern County, California

    NASA Astrophysics Data System (ADS)

    Talamantes, Jorge; Behseta, Sam; Zender, Charles S.

    2007-03-01

    Coccidioidomycosis (valley fever) is a fungal infection found in the southwestern US, northern Mexico, and some places in Central and South America. The fungus that causes it ( Coccidioides immitis) is normally soil-dwelling but, if disturbed, becomes air-borne and infects the host when its spores are inhaled. It is thus natural to surmise that weather conditions that foster the growth and dispersal of the fungus must have an effect on the number of cases in the endemic areas. We present here an attempt at the modeling of valley fever incidence in Kern County, California, by the implementation of a generalized auto regressive moving average (GARMA) model. We show that the number of valley fever cases can be predicted mainly by considering only the previous history of incidence rates in the county. The inclusion of weather-related time sequences improves the model only to a relatively minor extent. This suggests that fluctuations of incidence rates (about a seasonally varying background value) are related to biological and/or anthropogenic reasons, and not so much to weather anomalies.

  3. Sunflower (Helianthus annuus) pollination in California's Central Valley is limited by native bee nest site location.

    PubMed

    Sardiñas, Hillary S; Tom, Kathleen; Ponisio, Lauren Catherine; Rominger, Andrew; Kremen, Claire

    2016-03-01

    The delivery of ecosystem services by mobile organisms depends on the distribution of those organisms, which is, in turn, affected by resources at local and landscape scales. Pollinator-dependent crops rely on mobile animals like bees for crop production, and the spatial relationship between floral resources and nest location for these central-place foragers influences the delivery of pollination services. Current models that map pollination coverage in agricultural regions utilize landscape-level estimates of floral availability and nesting incidence inferred from expert opinion, rather than direct assessments. Foraging distance is often derived from proxies of bee body size, rather than direct measurements of foraging that account for behavioral responses to floral resource type and distribution. The lack of direct measurements of nesting incidence and foraging distances may lead to inaccurate mapping of pollination services. We examined the role of local-scale floral resource presence from hedgerow plantings on nest incidence of ground-nesting bees in field margins and within monoculture, conventionally managed sunflower fields in California's Central Valley. We tracked bee movement into fields using fluorescent powder. We then used these data to simulate the distribution of pollination services within a crop field. Contrary to expert opinion, we found that ground-nesting native bees nested both in fields and edges, though nesting rates declined with distance into field. Further, we detected no effect of field-margin floral enhancements on nesting. We found evidence of an exponential decay rate of bee movement into fields, indicating that foraging predominantly occurred in less than 1% of medium-sized bees' predicted typical foraging range. Although we found native bees nesting within agricultural fields, their restricted foraging movements likely centralize pollination near nest sites. Our data thus predict a heterogeneous distribution of pollination services

  4. Seasonal and diurnal variations in methane and carbon dioxide in the Kathmandu Valley in the foothills of the central Himalayas

    NASA Astrophysics Data System (ADS)

    Singh Mahata, Khadak; Panday, Arnico Kumar; Rupakheti, Maheswar; Singh, Ashish; Naja, Manish; Lawrence, Mark G.

    2017-10-01

    The SusKat-ABC (Sustainable Atmosphere for the Kathmandu Valley-Atmospheric Brown Clouds) international air pollution measurement campaign was carried out from December 2012 to June 2013 in the Kathmandu Valley and surrounding regions in Nepal. The Kathmandu Valley is a bowl-shaped basin with a severe air pollution problem. This paper reports measurements of two major greenhouse gases (GHGs), methane (CH4) and carbon dioxide (CO2), along with the pollutant CO, that began during the campaign and were extended for 1 year at the SusKat-ABC supersite in Bode, a semi-urban location in the Kathmandu Valley. Simultaneous measurements were also made during 2015 in Bode and a nearby rural site (Chanban) ˜ 25 km (aerial distance) to the southwest of Bode on the other side of a tall ridge. The ambient mixing ratios of methane (CH4), carbon dioxide (CO2), water vapor, and carbon monoxide (CO) were measured with a cavity ring-down spectrometer (G2401; Picarro, USA) along with meteorological parameters for 1 year (March 2013-March 2014). These measurements are the first of their kind in the central Himalayan foothills. At Bode, the annual average mixing ratios of CO2 and CH4 were 419.3 (±6.0) ppm and 2.192 (±0.066) ppm, respectively. These values are higher than the levels observed at background sites such as Mauna Loa, USA (CO2: 396.8 ± 2.0 ppm, CH4: 1.831 ± 0.110 ppm) and Waliguan, China (CO2: 397.7 ± 3.6 ppm, CH4: 1.879 ± 0.009 ppm) during the same period and at other urban and semi-urban sites in the region, such as Ahmedabad and Shadnagar (India). They varied slightly across the seasons at Bode, with seasonal average CH4 mixing ratios of 2.157 (±0.230) ppm in the pre-monsoon season, 2.199 (±0.241) ppm in the monsoon, 2.210 (±0.200) ppm in the post-monsoon, and 2.214 (±0.209) ppm in the winter season. The average CO2 mixing ratios were 426.2 (±25.5) ppm in the pre-monsoon, 413.5 (±24.2) ppm in the monsoon, 417.3 (±23.1) ppm in the post-monsoon, and 421.9 (±20

  5. Subaerially exposed Holocene coral reef, Enriquillo Valley, Dominican Republic

    NASA Technical Reports Server (NTRS)

    Mann, P.; Taylor, F. W.; Burke, K.; Kulstad, R.

    1984-01-01

    An extremely well-preserved Holocene fringing coral reef occurs at an average elevation of 5 m below sea level around the margins of the central Enriquillo Valley, Dominican Republic. The reef records the latest marine incursion from the east into an 85-km-long, 12-km-wide tectonic depression and appears to represent a unique preservation. Excellent cross sections of the reef exposed in erosional gullies reveal a composition and zonation typical of modern Caribbean reefs that are found in offshore low-energy environments. Radiocarbon age determinations (2) indicate that reef growth coincided with sea-level rise following the last ice age (5,930 + or - 100 to 4,760 + or - 90 yr B.P.). Deltaic deposition and possible vertical movements on active fault scarps dammed the eastern mouth of the valley and created Lago Enriquillo, the level of which was then rapidly lowered by evaporation in an arid climate to produce a saline lake approximately 40 m below sea level. Stratigraphic studies of rocks along the valley edge and data from drill holes in the basin center indicate that there were earlier post-Miocene marine incursions similar to that described here.

  6. Water-Resource Trends and Comparisons Between Partial-Development and October 2006 Hydrologic Conditions, Wood River Valley, South-Central Idaho

    USGS Publications Warehouse

    Skinner, Kenneth D.; Bartolino, James R.; Tranmer, Andrew W.

    2007-01-01

    This report analyzes trends in ground-water and surface-water data, documents 2006 hydrologic conditions, and compares 2006 and historic ground-water data of the Wood River Valley of south-central Idaho. The Wood River Valley extends from Galena Summit southward to the Timmerman Hills. It is comprised of a single unconfined aquifer and an underlying confined aquifer present south of Baseline Road in the southern part of the study area. Streams are well-connected to the shallow unconfined aquifer. Because the entire population of the area depends on ground water for domestic supply, either from domestic or municipal-supply wells, rapid population growth since the 1970s has raised concerns about the continued availability of ground and surface water to support existing uses and streamflow. To help address these concerns, this report evaluates ground- and surface-water conditions in the area before and during the population growth that started in the 1970s. Mean annual water levels in three wells (two completed in the unconfined aquifer and one in the confined aquifer) with more than 50 years of semi-annual measurements showed statistically significant declining trends. Mean annual and monthly streamflow trends were analyzed for three gaging stations in the Wood River Valley. The Big Wood River at Hailey gaging station (13139500) showed a statistically significant trend of a 25-percent increase in mean monthly base flow for March over the 90-year period of record, possibly because of earlier snowpack runoff. Both the 7-day and 30-day low-flow analyses for the Big Wood River near Bellevue gaging station (13141000) show a mean decrease of approximately 15 cubic feet per second since the 1940s, and mean monthly discharge showed statistically significant decreasing trends for December, January, and February. The Silver Creek at Sportsman Access near Picabo gaging station (13150430) also showed statistically significant decreasing trends in annual and mean monthly

  7. Valleytronics in merging Dirac cones: All-electric-controlled valley filter, valve, and universal reversible logic gate

    NASA Astrophysics Data System (ADS)

    Ang, Yee Sin; Yang, Shengyuan A.; Zhang, C.; Ma, Zhongshui; Ang, L. K.

    2017-12-01

    Despite much anticipation of valleytronics as a candidate to replace the aging complementary metal-oxide-semiconductor (CMOS) based information processing, its progress is severely hindered by the lack of practical ways to manipulate valley polarization all electrically in an electrostatic setting. Here, we propose a class of all-electric-controlled valley filter, valve, and logic gate based on the valley-contrasting transport in a merging Dirac cones system. The central mechanism of these devices lies on the pseudospin-assisted quantum tunneling which effectively quenches the transport of one valley when its pseudospin configuration mismatches that of a gate-controlled scattering region. The valley polarization can be abruptly switched into different states and remains stable over semi-infinite gate-voltage windows. Colossal tunneling valley-pseudomagnetoresistance ratio of over 10 000 % can be achieved in a valley-valve setup. We further propose a valleytronic-based logic gate capable of covering all 16 types of two-input Boolean logics. Remarkably, the valley degree of freedom can be harnessed to resurrect logical reversibility in two-input universal Boolean gate. The (2 +1 ) polarization states (two distinct valleys plus a null polarization) reestablish one-to-one input-to-output mapping, a crucial requirement for logical reversibility, and significantly reduce the complexity of reversible circuits. Our results suggest that the synergy of valleytronics and digital logics may provide new paradigms for valleytronic-based information processing and reversible computing.

  8. Optical manipulation of valley pseudospin

    DOE PAGES

    Ye, Ziliang; Sun, Dezheng; Heinz, Tony F.

    2016-09-19

    The coherent manipulation of spin and pseudospin underlies existing and emerging quantum technologies, including quantum communication and quantum computation. Valley polarization, associated with the occupancy of degenerate, but quantum mechanically distinct valleys in momentum space, closely resembles spin polarization and has been proposed as a pseudospin carrier for the future quantum electronics. Valley exciton polarization has been created in the transition metal dichalcogenide monolayers using excitation by circularly polarized light and has been detected both optically and electrically. In addition, the existence of coherence in the valley pseudospin has been identified experimentally. The manipulation of such valley coherence has, however,more » remained out of reach. In this paper, we demonstrate all-optical control of the valley coherence by means of the pseudomagnetic field associated with the optical Stark effect. Using below-bandgap circularly polarized light, we rotate the valley exciton pseudospin in monolayer WSe 2 on the femtosecond timescale. Both the direction and speed of the rotation can be manipulated optically by tuning the dynamic phase of excitons in opposite valleys. Finally, this study unveils the possibility of generation, manipulation, and detection of the valley pseudospin by coupling to photons.« less

  9. Multiple geophysical methods examining neotectonic blind structures in the Maradona valley, Central Precordillera (Argentina)

    NASA Astrophysics Data System (ADS)

    Lara, Gabriela; Klinger, Federico Lince; Perucca, Laura; Rojo, Guillermo; Vargas, Nicolás; Leiva, Flavia

    2017-08-01

    A high-resolution superficial geophysical study was carried out in an area of the retroarc region of the Andes mountains, located in the southwest of San Juan Province (31°45‧ S, 68°50‧ W), Central Precordillera of Argentina. The main objectives of this study were to confirm the presence of blind neotectonic structures and characterize them by observing variations in magnetic susceptibility, density and p-wave velocities. Geological evidence demonstrates the existence of a neotectonic fault scarps affecting Quaternary alluvial deposits in eastern piedmont of de Las Osamentas range, in addition to direct observation of the cinematic of this feature in several natural exposures. The Maradona valley is characterized by the imbricated eastern-vergence Maradona Fault System that uplifts Neogene sedimentary rocks (Albarracín Formation) over Quaternary (Late Pleistocene-Holocene) alluvial deposits. The combined application of different geophysical methods has allowed the characterization of a blind fault geometry also identified on a natural exposure. The magnetic data added to the gravimetric model, and its integration with a seismic profile clearly shows the existence of an anomalous zone, interpreted as uplifted blocks of Miocene sedimentary rocks of Formation Albarracín displaced over Quaternary deposits. The application and development of different geophysical methods, together with geological studies allow to significantly improving the knowledge of an area affected by Quaternary tectonic activity. Finally, this multidisciplinary study, applied in active blind structures is very relevant for future seismic hazard analysis on areas located very close to populated centers.

  10. SDSS IV MaNGA - sSFR profiles and the slow quenching of discs in green valley galaxies

    NASA Astrophysics Data System (ADS)

    Belfiore, Francesco; Maiolino, Roberto; Bundy, Kevin; Masters, Karen; Bershady, Matthew; Oyarzún, Grecco; Lin, Lihwai; Cano-Diaz, Mariana; Wake, David; Spindler, Ashley; Thomas, Daniel; Brownstein, Joel R.; Drory, Niv; Yan, Renbin

    2018-03-01

    We study radial profiles in Hα equivalent width and specific star formation rate (sSFR) derived from spatially-resolved SDSS-IV MaNGA spectroscopy to gain insight on the physical mechanisms that suppress star formation and determine a galaxy's location in the SFR-M_\\star diagram. Even within the star-forming `main sequence', the measured sSFR decreases with stellar mass, both in an integrated and spatially-resolved sense. Flat sSFR radial profiles are observed for log(M_\\star / M_⊙ ) < 10.5, while star-forming galaxies of higher mass show a significant decrease in sSFR in the central regions, a likely consequence of both larger bulges and an inside-out growth history. Our primary focus is the green valley, constituted by galaxies lying below the star formation main sequence, but not fully passive. In the green valley we find sSFR profiles that are suppressed with respect to star-forming galaxies of the same mass at all galactocentric distances out to 2 effective radii. The responsible quenching mechanism therefore appears to affect the entire galaxy, not simply an expanding central region. The majority of green valley galaxies of log(M_\\star / M_⊙ ) > 10.0 are classified spectroscopically as central low-ionisation emission-line regions (cLIERs). Despite displaying a higher central stellar mass concentration, the sSFR suppression observed in cLIER galaxies is not simply due to the larger mass of the bulge. Drawing a comparison sample of star forming galaxies with the same M_\\star and Σ _{1 kpc} (the mass surface density within 1 kpc), we show that a high Σ _{1 kpc} is not a sufficient condition for determining central quiescence.

  11. SDSS IV MaNGA - sSFR profiles and the slow quenching of discs in green valley galaxies

    NASA Astrophysics Data System (ADS)

    Belfiore, Francesco; Maiolino, Roberto; Bundy, Kevin; Masters, Karen; Bershady, Matthew; Oyarzún, Grecco A.; Lin, Lihwai; Cano-Diaz, Mariana; Wake, David; Spindler, Ashley; Thomas, Daniel; Brownstein, Joel R.; Drory, Niv; Yan, Renbin

    2018-07-01

    We study radial profiles in H α equivalent width and specific star formation rate (sSFR) derived from spatially resolved SDSS-IV MaNGA spectroscopy to gain insight on the physical mechanisms that suppress star formation and determine a galaxy's location in the SFR-M⋆ diagram. Even within the star-forming `main sequence', the measured sSFR decreases with stellar mass, in both an integrated and spatially resolved sense. Flat sSFR radial profiles are observed for log(M⋆/M⊙) < 10.5, while star-forming galaxies of higher mass show a significant decrease in sSFR in the central regions, a likely consequence of both larger bulges and an inside-out growth history. Our primary focus is the green valley, constituted by galaxies lying below the star formation main sequence, but not fully passive. In the green valley we find sSFR profiles that are suppressed with respect to star-forming galaxies of the same mass at all galactocentric distances out to 2 effective radii. The responsible quenching mechanism therefore appears to affect the entire galaxy, not simply an expanding central region. The majority of green valley galaxies of log(M⋆/M⊙) > 10.0 are classified spectroscopically as central low-ionization emission-line regions (cLIERs). Despite displaying a higher central stellar mass concentration, the sSFR suppression observed in cLIER galaxies is not simply due to the larger mass of the bulge. Drawing a comparison sample of star-forming galaxies with the same M⋆ and Σ _{1 kpc} (the mass surface density within 1 kpc), we show that a high Σ _{1 kpc} is not a sufficient condition for determining central quiescence.

  12. Change in Total Water in California's Mountains and Groundwater in Central Valley During the 2011-2014 Drought From GPS, GRACE, and InSAR

    NASA Astrophysics Data System (ADS)

    Argus, D. F.; Fu, Y.; Landerer, F. W.; Farr, T.; Watkins, M. M.; Famiglietti, J. S.

    2014-12-01

    Changes in total water thickness in most of California are being estimated using GPS measurements of vertical ground displacement. The Sierra Nevada each year subsides about 12 mm in the fall and winter due to the load of rain and snow, then rises about the same amount in the spring and summer when the snow melts, water runs off, and soil moisture evaporates. Earth's elastic response to a surface load is well known (except at thick sedimentary basins). Changes in equivalent water thickness can thus be inferred [Argus Fu Landerer 2014]. The average seasonal change in total water thickness is found to be 0.5 meters in the Sierra Nevada and Klamath Mountains and 0.1 meters in the Great Basin. The average seasonal change in the Sierra Nevada Mountains estimated with GPS is 35 Gigatons. GPS vertical ground displacements are furthermore being used to estimate changes in water in consecutive years of either drought or heavy precipitation. Changes in the sum of snow and soil moisture during California's drought from June 2011 to June 2014 are estimated from GPS in this study. Changes in water in California's massive reservoirs are well known and removed, yielding an estimate of change in the thickness of snow plus soil moisture. Water loss is found to be largest near the center of the southern Sierra Nevada (0.8 m equivalent water thickness) and smaller in the northern Sierra Nevada and southern Klamath Mountains (0.3 m). The GPS estimates of changes in the sum of snow and soil moisture complement GRACE observations of water change in the Sacramento-San Joaquin River basin. Whereas GPS provides estimates of water change at high spatial resolution in California's mountains, GRACE observes changes in groundwater in the Central Valley. We will further compare and contrast the GPS and GRACE measurements, and also evaluate the finding of Amos et al. [2014] that groundwater loss in the southern Central Valley (Tulare Basin) is causing the mountains on either side to rise at 1 to

  13. Chuckwalla Valley multiple-well monitoring site, Chuckwalla Valley, Riverside County

    USGS Publications Warehouse

    Everett, Rhett

    2013-01-01

    The U.S. Geological Survey (USGS), in cooperation with the Bureau of Land Management, is evaluating the geohydrology and water availability of the Chuckwalla Valley, California. As part of this evaluation, the USGS installed the Chuckwalla Valley multiple-well monitoring site (CWV1) in the southeastern portion of the Chuckwalla Basin. Data collected at this site provide information about the geology, hydrology, geophysics, and geochemistry of the local aquifer system, thus enhancing the understanding of the geohydrologic framework of the Chuckwalla Valley. This report presents construction information for the CWV1 multiple-well monitoring site and initial geohydrologic data collected from the site.

  14. Adsorption studies of the herbicide simazine in agricultural soils of the Aconcagua valley, central Chile.

    PubMed

    Flores, Cecilia; Morgante, Verónica; González, Myriam; Navia, Rodrigo; Seeger, Michael

    2009-03-01

    Simazine is a s-triazine herbicide that has been applied worldwide for agriculture. This herbicide is the second most commonly detected pesticide in surface and groundwater in the United States, Europe and Australia. In this study, simazine adsorption behaviour was studied in two agricultural soils of the Aconcagua valley, central Chile. The two studied soils were soil A (loam, 8.5% organic matter content) and soil B (clay-loam, 3.5% organic matter content). Three times higher simazine adsorption capacity was observed in soil A (68.03 mg kg(-1)) compared to soil B (22.03 mg kg(-1)). The simazine adsorption distribution coefficients (K(d)) were 9.32 L kg(-1) for soil A and 7.74 L kg(-1) for soil B. The simazine adsorption enthalpy in soil A was -21.0 kJ mol(-1) while in soil B the adsorption enthalpy value was -11.5 kJ mol(-1). These results indicate that simazine adsorption process in these soils is exothermic, governing H bonds the adsorption process of simazine in both the loam and clay-loam soils. These results and the potentiometric profiles of both soils, suggest that simazine adsorption in soil A is mainly governed by simazine-organic matter interactions and in soil B by simazine-clay interactions. The understanding of simazine sorption-desorption processes is essential to determine the pesticide fate and availability in soil for pest control, biodegradation, runoff and leaching.

  15. Serosurveillance of infectious agents in equines of the Central Valley of Costa Rica.

    PubMed

    Jiménez, D; Romero-Zuñiga, J J; Dolz, G

    2014-01-01

    Blood samples from 181 equines from the Central Valley of Costa Rica were collected in the year 2012 to determine the presence of antibodies against selected infectious agents in horses and to determine the risk factors associated with these agents. The presence of antibodies against Equine Infectious Anemia Virus (EIAV), Equine Herpes Virus 1 and 4 (EHV-1 and EHV-4), West Nile Virus (WNV), Influenza A Virus (IAV), Equine Viral Arteritis Virus (EVAV), Babesia caballi, Theileria equi, Neospora caninum and Chlamydia abortus was determined using commercial assays, and risk factors associated with seropositivity to the different infectious agents was established. The most seroprevalent agent detected was EHV-4 (96.7%), followed by WNV (44.2%), and IAV (41.8%). Horses >3 years, used for work or sports, and with access to pastures, had significantly increased probability to be seropositive to WNV, whereas horses used for breeding and recreational purposes, being stabled, and without access to pastures, had significantly greater probability to be seropositive to IAV. Seroprevalence to B. caballi (19.9%) was lower than to T. equi (38.1%). For B. caballi, access to pastures was determined as a risk factor, whereas being older than 3 years was established as a risk factor for T. equi. Low seroprevalences were determined for EHV-1 (5.0%), EVAV (5.0%), C. abortus (4.8%), and N. caninum (4.4%). Mares having history of abortion were more likely to be seropositive to EHV-1, whereas horses >3 years, used for work and sports, and mares having multiple parturitions, were more likely to be seropositive to N. caninum. None of the horses were seropositive to EIAV. Earlier, only diseases caused by EIAV, WNV and piroplasmosis were reported in Costa Rica. The present study however, determined the presence of carriers for EHV-1, EHV-4, and EIAV.

  16. Serosurveillance of infectious agents in equines of the Central Valley of Costa Rica

    PubMed Central

    Jiménez, D.; Romero-Zuñiga, J.J.; Dolz, G.

    2014-01-01

    Blood samples from 181 equines from the Central Valley of Costa Rica were collected in the year 2012 to determine the presence of antibodies against selected infectious agents in horses and to determine the risk factors associated with these agents. The presence of antibodies against Equine Infectious Anemia Virus (EIAV), Equine Herpes Virus 1 and 4 (EHV-1 and EHV-4), West Nile Virus (WNV), Influenza A Virus (IAV), Equine Viral Arteritis Virus (EVAV), Babesia caballi, Theileria equi, Neospora caninum and Chlamydia abortus was determined using commercial assays, and risk factors associated with seropositivity to the different infectious agents was established. The most seroprevalent agent detected was EHV-4 (96.7%), followed by WNV (44.2%), and IAV (41.8%). Horses >3 years, used for work or sports, and with access to pastures, had significantly increased probability to be seropositive to WNV, whereas horses used for breeding and recreational purposes, being stabled, and without access to pastures, had significantly greater probability to be seropositive to IAV. Seroprevalence to B. caballi (19.9%) was lower than to T. equi (38.1%). For B. caballi, access to pastures was determined as a risk factor, whereas being older than 3 years was established as a risk factor for T. equi. Low seroprevalences were determined for EHV-1 (5.0%), EVAV (5.0%), C. abortus (4.8%), and N. caninum (4.4%). Mares having history of abortion were more likely to be seropositive to EHV-1, whereas horses >3 years, used for work and sports, and mares having multiple parturitions, were more likely to be seropositive to N. caninum. None of the horses were seropositive to EIAV. Earlier, only diseases caused by EIAV, WNV and piroplasmosis were reported in Costa Rica. The present study however, determined the presence of carriers for EHV-1, EHV-4, and EIAV. PMID:26623349

  17. Central New York's New Workforce

    ERIC Educational Resources Information Center

    Center for an Urban Future, 2009

    2009-01-01

    Conducted in late 2008 in partnership with the Greater Syracuse Chamber of Commerce and the Mohawk Valley Chamber of Commerce, this is the largest survey ever taken of Central New York businesses regarding the English language skills of the area workforce. The online survey was emailed to several hundred local businesses; 126 responses were…

  18. Central California Action Associates, Inc.

    ERIC Educational Resources Information Center

    Sortor, Maia, Comp.

    The overall goal of the Central California Action Associates Inc. (CCAA) program is to provide basic education and pre-vocational training so that migrant and seasonal adult farm workers will be able to upgrade their economic and social lives. Without increased educational attainment, the San Joaquin Valley farm workers face a grim future because…

  19. Geologic cross section C-C' through the Appalachian basin from Erie County, north-central Ohio, to the Valley and Ridge province, Bedford County, south-central Pennsylvania

    USGS Publications Warehouse

    Ryder, Robert T.; Trippi, Michael H.; Swezey, Christopher S.; Crangle, Robert D.; Hope, Rebecca S.; Rowan, Elisabeth L.; Lentz, Erika E.

    2012-01-01

    Geologic cross section C-C' is the third in a series of cross sections constructed by the U.S. Geological Survey (USGS) to document and improve understanding of the geologic framework and petroleum systems of the Appalachian basin. Cross section C-C' provides a regional view of the structural and stratigraphic framework of the Appalachian basin from north-central Ohio to the Valley and Ridge province in south-central Pennsylvania, a distance of approximately 260 miles (mi). This cross section is a companion to cross sections E-E' and D-D' that are located about 50 to 125 mi and 25 to 50 mi, respectively, to the southwest. Cross section C-C' contains much information that is useful for evaluating energy resources in the Appalachian basin. Although specific petroleum systems are not identified on the cross section, many of their key elements (such as source rocks, reservoir rocks, seals, and traps) can be inferred from lithologic units, unconformities, and geologic structures shown on the cross section. Other aspects of petroleum systems (such as the timing of petroleum generation and preferred migration pathways) may be evaluated by burial history, thermal history, and fluid flow models based on what is shown on the cross section. Cross section C-C' also provides a general framework (stratigraphic units and general rock types) for the coal-bearing section, although the cross section lacks the detail to illustrate key elements of coal systems (such as paleoclimate, coal quality, and coal rank). In addition, cross section C-C' may be used as a reconnaissance tool to identify plausible geologic structures and strata for the subsurface storage of liquid waste or for the sequestration of carbon dioxide.

  20. Age, genesis, and paleoclimatic interpretation of the Sangamon/Loveland complex in the Lower Mississippi Valley, USA

    USGS Publications Warehouse

    Markewich, H.W.; Wysocki, D.A.; Pavich, M.J.; Rutledge, E.M.

    2011-01-01

    For more than a century, the Sangamon paleosol (the Sangamon) has been an integral part of geologic and pedologic investigations in the central United States, including the Upper Mississippi and Lower Missouri River Valleys. Compositional, pedologic, micromorphologic, stratigraphic, and age data indicate that the prominent reddish paleosol developed in silt-rich deposits of the Lower Mississippi Valley, from southernmost Illinois to northwestern Mississippi, represents multiple periods of soil formation, and is wholly or in part time equivalent to the Sangamon of the central United States. Thermoluminescence data, for localities where the Sangamon developed in loess, indicate that the primary period of loess deposition was from 190 to 130 ka (oxygen isotope stage, OIS6), that loess deposition continued intermittently from 130 to 74 ka (OIS5), and that deposition was wholly or in part coeval with Loveland loess deposition in the central United States. Beryllium-10, chemical, and pedologic data indicate that in the Lower Mississippi Valley: (1) the Sangamon represents a minimum time period of 60-80 k.y.; (2) there were at least two periods of soil formation, ca. 130-90 ka and 74-58 ka (OIS4); and (3) rates of weathering and pedogenesis equaled or exceeded the net loess-accumulation rate until at least 46 ka (OIS3) and resulted in development of a paleosol in the overlying basal Roxana Silt. Along a N-S transect from southern Illinois to western Mississippi, Sangamon macroscopic characteristics as well asthe micro-morphology, chemistry, and mineralogy, suggest a regional paleoclimate during periods of soil formation that: (1) was warm to hot, with a wider range in temperature, precipitation, and evapotranspiration than present; (2) had seasonal to decadal or longer periods of drought; and (3) had down-valley (southward) trends of increasing temperature and precipitation and decreasing seasonality and variation in annualto decadal precipitation. ?? 2011 Geological

  1. Rift Valley fever virus-infected mosquito ova and associated pathology: possible implications for endemic maintenance

    USDA-ARS?s Scientific Manuscript database

    Background: Endemic/enzootic maintenance mechanisms like vertical transmission, pathogen passage from infected adults to their offspring, are central in the epidemiology of zoonotic pathogens. In Kenya, Rift Valley fever virus (RVFV) may be maintained by vertical transmission in ground-pool mosquit...

  2. Hydrologic conditions in the Bill Williams River National Wildlife Refuge and Planet Valley, Arizona, 2000

    USGS Publications Warehouse

    Wilson, Richard P.; Owen-Joyce, Sandra J.

    2002-01-01

    During a period of sustained base-flow conditions in the Bill Williams River below Alamo Dam in west central Arizona from March to July 2000, the channel of the river through Planet Valley was dry, and the water table sloped almost due west parallel to the main slope of the flood plain. Water from the river infiltrated into the channel bottom at the head of Planet Valley, moved downgradient in the subsurface, and reappeared in the channel about 0.3 mile downstream from the east boundary of the Bill Williams River National Wildlife Refuge. A river aquifer in hydraulic connection with the Bill Williams River was mapped from a point 6.3 miles upstream from Highway 95 to the upstream end of Planet Valley. Formations that make up the river aquifer in Planet Valley are younger alluvium, older alluviums, and fanglomerate. Total thickness of the river aquifer probably is less than 200 feet in the bedrock canyons to as much as 1,035 feet in Planet Valley. The purpose of this study was to investigate the current hydrologic conditions along the Bill Williams River, which included an inventory of wells within the river aquifer of the Colorado River and in Planet Valley, and to determine the configuration of the water table. A map shows the elevation and configuration of the water table from the east end of Planet Valley to the confluence of the Bill Williams River with Lake Havasu.

  3. Water-quality assessment of the Rio Grande Valley, Colorado, New Mexico, and Texas; shallow ground-water quality of a land-use area in the San Luis Valley, south-central Colorado, 1993

    USGS Publications Warehouse

    Anderholm, S.K.

    1996-01-01

    This report describes the quality of shallow ground water in an agricultural area in the San Luis Valley, Colorado, and discusses how natural and human factors affect the quality of shallow ground water. Thirty-five wells were installed, and water samples were collected from these wells and analyzed for selected dissolved common constituents, nutrients, trace elements, radionuclides, and synthetic organic compounds. The San Luis Valley is a high intermontane valley that is partially drained by the Rio Grande. The San Luis Valley land-use study area was limited to a part of the valley where the depth to water is generally less than 25 feet. The area where the 35 monitor wells were installed was further limited to the part of the study area where center-pivot overhead sprinklers are used to irrigate crops. Precipitation, runoff from adjacent mountainous areas, and ground-water inflow from the adjacent mountainous areas are the main sources of water to the aquifers in the San Luis Valley. Discharge of water from the shallow, unconfined aquifer in the valley is mainly from evapotranspiration. The dominant land use in the San Luis Valley is agriculture, although nonirrigated land and residential land are interspersed with agricultural land. Alfalfa, native hay, barley, wheat, potatoes, and other vegetables are the main crops. Dissolved-solids concentrations in shallow ground water sampled ranged from 75 to 1,960 milligrams per liter. The largest median concentration of cations was for calcium, and the largest median concentration of anions was for bicarbonate in shallow ground water in the San Luis Valley. Calcium concentrations ranged from 7.5 to 300 milligrams per liter, and bicarbonate concentrations ranged from 28 to 451 milligrams per liter. Nitrite plus nitrate concentrations ranged from less than 0.1 to 58 milligrams per liter as N; water from 11 wells had nitrite plus nitrate concentrations greater than 10 milligrams per liter as N. With the exception of the

  4. Valley-Fill Sandstones in the Kootenai Formation on the Crow Indian Reservation, South-Central Montana

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lopez, David A

    Subsurface data continues to be collected, organized, and a digital database is being prepared for the project. An ACCESS database and PC-Arcview is being used to manage and interpret the data. Well data and base map data have been successfully imported into Arcview and customized to meet the needs of this project. Log tops and other data from about ¾ of the exploration wells in the area have been incorporated into the data base. All of the four 30" X 60" geologic quadrangles have been scanned to produce a digital surface geologic data base for the Crow Reservation and allmore » are nearing completion. Formal technical review prior to publication has been completed for all the quadrangles; Billings, Bridger; Hardin, and Lodge Grass. Final GIS edits are being made before being forwarded to the Bureau's Publications Department. Field investigations were completed during the third quarter, 1997. With the help of a student field assistant from the Crow Tribe, the entire project area was inventoried for the presence of valley-fill deposits in the Kootenai Formation. Field inventory has resulted in the identification of nine exposures of thick valley-fill deposits. These appear to represent at least four major westward-trending valley systems. All the channel localities have been measured and described in detail and paleocurrent data has been collected from all but one locality. In addition, two stratigraphic sections were measured in areas where channels are absent. One channel has bee traced over a distance of about 60 miles and exhibits definite paleostructural control. An abstract describing this channel has been submitted and accepted for presentation at the Williston Basin Symposium in October, 1998.« less

  5. Molecular identification of Armillaria gallica from the Niobrara Valley Preserve in Nebraska

    Treesearch

    Mee-Sook Kim; Ned B. Klopfenstein

    2011-01-01

    Armillaria isolates were collected from a unique forest ecosystem in the Niobrara Valley Preserve in Nebraska, USA, which comprises a glacial and early postglacial refugium in the central plains of North America. The isolates were collected from diverse forest trees representing a unique mixture of forest types. Combined methods of rDNA sequencing and flow cytometric...

  6. Boundary of the Eagle River Watershed Valley-Fill Aquifer, Eagle County, North-Central Colorado, 2006-2007

    USGS Publications Warehouse

    Rupert, Michael G.; Plummer, Niel

    2009-01-01

    This vector data set delineates the approximate boundary of the Eagle River watershed valley-fill aquifer (ERWVFA). This data set was developed by a cooperative project between the U.S. Geological Survey, Eagle County, the Eagle River Water and Sanitation District, the Town of Eagle, the Town of Gypsum, and the Upper Eagle Regional Water Authority. This project was designed to evaluate potential land-development effects on groundwater and surface-water resources so that informed land-use and water management decisions can be made. The boundary of the ERWVFA was developed by combining information from two data sources. The first data source was a 1:250,000-scale geologic map of the Leadville quadrangle developed by Day and others (1999). The location of Quaternary sediments was used as a first approximation of the ERWVFA. The boundary of the ERWVFA was further refined by overlaying the geologic map with Digital Raster Graphic (DRG) scanned images of 1:24,000 topographic maps (U.S. Geological Survey, 2001). Where appropriate, the boundary of the ERWVFA was remapped to correspond with the edge of the valley-fill aquifer marked by an abrupt change in topography at the edge of the valley floor throughout the Eagle River watershed. The boundary of the ERWVFA more closely resembles a hydrogeomorphic region presented by Rupert (2003, p. 8) because it is based upon general geographic extents of geologic materials and not on an actual aquifer location as would be determined through a rigorous hydrogeologic investigation.

  7. Sediment storage and transport in Pancho Rico Valley during and after the Pleistocene-Holocene transition, Coast Ranges of central California (Monterey County)

    USGS Publications Warehouse

    Garcia, A.F.; Mahan, S.A.

    2009-01-01

    Factors influencing sediment transport and storage within the 156??6 km2 drainage basin of Pancho Rico Creek (PRC), and sediment transport from the PRC drainage basin to its c. 11000 km2 mainstem drainage (Salinas River) are investigated. Numeric age estimates are determined by optically stimulated luminescence (OSL) dating on quartz grains from three sediment samples collected from a 'quaternary terrace a (Qta)' PRC terrace/PRC-tributary fan sequence, which consists dominantly of debris flow deposits overlying fluvial sediments. OSL dating results, morphometric analyses of topography, and field results indicate that the stormy climate of the Pleistocene-Holocene transition caused intense debris-flow erosion of PRC- tributary valleys. However, during that time, the PRC channel was backfilled by Qta sediment, which indicates that there was insufficient discharge in PRC to transport the sediment load produced by tributary-valley denudation. Locally, Salinas Valley alluvial stratigraphy lacks any record of hillslope erosion occurring during the Pleistocene-Holocene transition, in that the alluvial fan formed where PRC enters the Salinas Valley lacks lobes correlative to Qta. This indicates that sediment stripped from PRC tributaries was mostly trapped in Pancho Rico Valley despite the relatively moist climate of the Pleistocene-Holocene transition. Incision into Qta did not occur until PRC enlarged its drainage basin by c. 50% through capture of the upper part of San Lorenzo Creek, which occurred some time after the Pleistocene-Holocene transition. During the relatively dry Holocene, PRC incision through Qta and into bedrock, as well as delivery of sediment to the San Ardo Fan, were facilitated by the discharge increase associated with stream-capture. The influence of multiple mechanisms on sediment storage and transport in the Pancho Rico Valley-Salinas Valley system exemplifies the complexity that (in some instances) must be recognized in order to correctly

  8. Observation of acoustic valley vortex states and valley-chirality locked beam splitting

    NASA Astrophysics Data System (ADS)

    Ye, Liping; Qiu, Chunyin; Lu, Jiuyang; Wen, Xinhua; Shen, Yuanyuan; Ke, Manzhu; Zhang, Fan; Liu, Zhengyou

    2017-05-01

    We report an experimental observation of the classical version of valley polarized states in a two-dimensional hexagonal sonic crystal. The acoustic valley states, which carry specific linear momenta and orbital angular momenta, were selectively excited by external Gaussian beams and conveniently confirmed by the pressure distribution outside the crystal, according to the criterion of momentum conservation. The vortex nature of such intriguing bulk crystal states was directly characterized by scanning the phase profile inside the crystal. In addition, we observed a peculiar beam-splitting phenomenon, in which the separated beams are constructed by different valleys and locked to the opposite vortex chirality. The exceptional sound transport, encoded with valley-chirality locked information, may serve as the basis of designing conceptually interesting acoustic devices with unconventional functions.

  9. Dry Valleys, Antarctica

    NASA Image and Video Library

    2009-11-02

    The McMurdo Dry Valleys are a row of valleys west of McMurdo Sound, Antarctica. They are so named because of their extremely low humidity and lack of snow and ice cover. This image was acquired December 8, 2002 by NASA Terra spacecraft.

  10. 14. Drawing showing stress for central viaduct, Walworth Run portion ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. Drawing showing stress for central viaduct, Walworth Run portion 1885. Drawing courtesy Engineering Department, City of Cleveland. - Abbey Avenue Viaduct, Spanning Walworth Valley at Abbey Avenue, Cleveland, Cuyahoga County, OH

  11. Analysis of Mining-induced Valley Closure Movements

    NASA Astrophysics Data System (ADS)

    Zhang, C.; Mitra, R.; Oh, J.; Hebblewhite, B.

    2016-05-01

    Valley closure movements have been observed for decades in Australia and overseas when underground mining occurred beneath or in close proximity to valleys and other forms of irregular topographies. Valley closure is defined as the inward movements of the valley sides towards the valley centreline. Due to the complexity of the local geology and the interplay between several geological, topographical and mining factors, the underlying mechanisms that actually cause this behaviour are not completely understood. A comprehensive programme of numerical modelling investigations has been carried out to further evaluate and quantify the influence of a number of these mining and geological factors and their inter-relationships. The factors investigated in this paper include longwall positional factors, horizontal stress, panel width, depth of cover and geological structures around the valley. It is found that mining in a series passing beneath the valley dramatically increases valley closure, and mining parallel to valley induces much more closure than other mining orientations. The redistribution of horizontal stress and influence of mining activity have also been recognised as important factors promoting valley closure, and the effect of geological structure around the valley is found to be relatively small. This paper provides further insight into both the valley closure mechanisms and how these mechanisms should be considered in valley closure prediction models.

  12. The Inter-Valley Soil Comparative Survey: the ecology of Dry Valley edaphic microbial communities

    PubMed Central

    Lee, Charles K; Barbier, Béatrice A; Bottos, Eric M; McDonald, Ian R; Cary, Stephen Craig

    2012-01-01

    Recent applications of molecular genetics to edaphic microbial communities of the McMurdo Dry Valleys and elsewhere have rejected a long-held belief that Antarctic soils contain extremely limited microbial diversity. The Inter-Valley Soil Comparative Survey aims to elucidate the factors shaping these unique microbial communities and their biogeography by integrating molecular genetic approaches with biogeochemical analyses. Although the microbial communities of Dry Valley soils may be complex, there is little doubt that the ecosystem's food web is relatively simple, and evidence suggests that physicochemical conditions may have the dominant role in shaping microbial communities. To examine this hypothesis, bacterial communities from representative soil samples collected in four geographically disparate Dry Valleys were analyzed using molecular genetic tools, including pyrosequencing of 16S rRNA gene PCR amplicons. Results show that the four communities are structurally and phylogenetically distinct, and possess significantly different levels of diversity. Strikingly, only 2 of 214 phylotypes were found in all four valleys, challenging a widespread assumption that the microbiota of the Dry Valleys is composed of a few cosmopolitan species. Analysis of soil geochemical properties indicated that salt content, alongside altitude and Cu2+, was significantly correlated with differences in microbial communities. Our results indicate that the microbial ecology of Dry Valley soils is highly localized and that physicochemical factors potentially have major roles in shaping the microbiology of ice-free areas of Antarctica. These findings hint at links between Dry Valley glacial geomorphology and microbial ecology, and raise previously unrecognized issues related to environmental management of this unique ecosystem. PMID:22170424

  13. 27 CFR 9.132 - Rogue Valley.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Rogue Valley. 9.132... Rogue Valley. (a) Name. The name of the viticultural area described in this section is “Rouge Valley.” (b) Approved map. The appropriate map for determining the boundaries of the Rogue Valley viticultural...

  14. Neogene Rift Propagation of the East African Rift System (EARS) into Central Africa and its Implications: Tectonic, Topographic and Geomorphic Impacts of the Luangwa and Luapula Rift Valleys on the Upper Congo Drainage Basin, Lake Bangweulu Wetlands and the Development of the Diffuse Southwestern Tip of the EARS.

    NASA Astrophysics Data System (ADS)

    Daly, M. C.; Watts, A. B.

    2017-12-01

    Integration of geomorphology, seismic reflection and gravity data, seismicity, DEM analysis and modelling defines a zone of NE/SW trending rifts extending into Central and SW Africa, orthogonal to the conventionally defined East African Rift System (EARS). These large-scale tectonic features have a relatively low level of seismicity and volcanism compared to the EARS, yet they generate significant topography and control the upper Congo drainage basin. They may also represent the beginning of an active but diffuse plate boundary developing to the southwest across Central Africa. The dominant feature of this broad zone is the Luangwa Rift Valley of eastern Zambia. Seismic reflection data show the Luangwa Rift developed as a thick ( 5km) Permo-Triassic basin. Inverted in the Mesozoic, it then experienced major Neogene extensional reactivation. The latter resulted in today's major border faults of varying polarity, with fault plane escarpments of up to 1000m, and associated rift flank uplifts that elevate the Central African plateau surface by 200 m. Late Miocene alluvial fans indicate a minimum age for the initiation of reactivation. Although having similar structural features to the EARS, the Luangwa Rift has a lower level of active seismicity and volcanism. 400 km northwest of the Luangwa, the north/south Luapula rift valley passes into the NE trending Mweru and Mweru Wantipa rift lakes. Pronounced border faults and fault terraces mark the NW and SE margins of these shallow lakes. Between the Luangwa and Luapula rift valleys lies the extensive upper Congo drainage basin of the Chambeshi river and the Lake Bangweulu wetlands. DEM mapping of topography from the Luangwa rift to the Luapula-Mweru Wantipa rift shows a low amplitude, large wavelength flexure of the Central African plateau surface compatible with an effective elastic thickness of 35 km. This regional warping controls the location and shape of the Chambeshi drainage basin and the Lake Bangweulu Wetlands

  15. Improving Flood Risk Management for California's Central Valley: How the State Developed a Toolbox for Large, System-wide Studies

    NASA Astrophysics Data System (ADS)

    Pingel, N.; Liang, Y.; Bindra, A.

    2016-12-01

    More than 1 million Californians live and work in the floodplains of the Sacramento-San Joaquin Valley where flood risks are among the highest in the nation. In response to this threat to people, property and the environment, the Department of Water Resources (DWR) has been called to action to improve flood risk management. This has transpired through significant advances in development of flood information and tools, analysis, and planning. Senate Bill 5 directed DWR to prepare the Central Valley Flood Protection Plan (CVFPP) and update it every 5 years. A key component of this aggressive planning approach is answering the question: What is the current flood risk, and how would proposed improvements change flood risk throughout the system? Answering this question is a substantial challenge due to the size and complexity of the watershed and flood control system. The watershed is roughly 42,000 sq mi, and flows are controlled by numerous reservoirs, bypasses, and levees. To overcome this challenge, the State invested in development of a comprehensive analysis "tool box" through various DWR programs. Development of the tool box included: collection of hydro-meteorological, topographic, geotechnical, and economic data; development of rainfall-runoff, reservoir operation, hydraulic routing, and flood risk analysis models; and development of specialized applications and computing schemes to accelerate the analysis. With this toolbox, DWR is analyzing flood hazard, flood control system performance, exposure and vulnerability of people and property to flooding, consequence of flooding for specific events, and finally flood risk for a range of CVFPP alternatives. Based on the results, DWR will put forward a State Recommended Plan in the 2017 CVFPP. Further, the value of the analysis tool box extends beyond the CVFPP. It will serve as a foundation for other flood studies for years to come and has already been successfully applied for inundation mapping to support emergency

  16. Railroad Valley, Nevada

    NASA Image and Video Library

    2002-02-01

    Information from images of Railroad Valley, Nevada captured on August 17, 2001 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) may provide a powerful tool for monitoring crop health and maintenance procedures. These images cover an area of north central Nevada. The top image shows irrigated fields, with healthy vegetation in red. The middle image highlights the amount of vegetation. The color code shows highest vegetation content in red, orange, yellow, green, blue, and purple and the lowest in black. The final image is a thermal infrared channel, with warmer temperatures in white and colder in black. In the thermal image, the northernmost and westernmost fields are markedly colder on their northwest areas, even though no differences are seen in the visible image or the second, Vegetation Index image. This can be attributed to the presence of excess water, which can lead to crop damage. http://photojournal.jpl.nasa.gov/catalog/PIA03463

  17. Potential for a significant deep basin geothermal system in Tintic Valley, Utah

    NASA Astrophysics Data System (ADS)

    Hardwick, C.; Kirby, S.

    2014-12-01

    The combination of regionally high heat flow, deep basins, and permeable reservoir rocks in the eastern Great Basin may yield substantial new geothermal resources. We explore a deep sedimentary basin geothermal prospect beneath Tintic Valley in central Utah using new 2D and 3D models coupled with existing estimates of heat flow, geothermometry, and shallow hydrologic data. Tintic Valley is a sediment-filled basin bounded to the east and west by bedrock mountain ranges where heat-flow values vary from 85 to over 240 mW/m2. Based on modeling of new and existing gravity data, a prominent 30 mGal low indicates basin fill thickness may exceed 2 km. The insulating effect of relatively low thermal conductivity basin fill in Tintic Valley, combined with typical Great Basin heat flow, predict temperatures greater than 150 °C at 3 km depth. The potential reservoir beneath the basin fill is comprised of Paleozoic carbonate and clastic rocks. The hydrology of the Tintic Valley is characterized by a shallow, cool groundwater system that recharges along the upper reaches of the basin and discharges along the valley axis and to a series of wells. The east mountain block is warm and dry, with groundwater levels just above the basin floor and temperatures >50 °C at depth. The west mountain block contains a shallow, cool meteoric groundwater system. Fluid temperatures over 50 °C are sufficient for direct-use applications, such as greenhouses and aquaculture, while temperatures exceeding 140°C are suitable for binary geothermal power plants. The geologic setting and regionally high heat flow in Tintic Valley suggest a geothermal resource capable of supporting direct-use geothermal applications and binary power production could be present.

  18. Budgets and chemical characterization of groundwater for the Diamond Valley flow system, central Nevada, 2011–12

    USGS Publications Warehouse

    Berger, David L.; Mayers, C. Justin; Garcia, C. Amanda; Buto, Susan G.; Huntington, Jena M.

    2016-07-29

    The pre-development, steady state, groundwater budget for the Diamond Valley flow system was estimated at about 70,000 acre-ft/yr of inflow and outflow. During years 2011–12, inflow components of groundwater recharge from precipitation and subsurface inflow from adjacent basins totaled 70,000 acre-ft/yr for the DVFS, whereas outflow components included 64,000 acre-ft/yr of groundwater evapotranspiration and 69,000 acre-ft/yr of net groundwater withdrawals, or net pumpage. Spring discharge in northern Diamond Valley declined about 6,000 acre-ft/yr between pre-development time and years 2011–12. Assuming net groundwater withdrawals minus spring flow decline is equivalent to the storage change, the 2011–12 summation of inflow and storage change was balanced with outflow at about 133,000 acre-ft/yr.

  19. Influence of grazing and available moisture on breeding densities of grassland birds in the central platte river valley, Nebraska

    USGS Publications Warehouse

    Kim, D.H.; Newton, W.E.; Lingle, G.R.; Chavez-Ramirez, F.

    2008-01-01

    We investigated the relationship between grassland breeding bird densities and both grazing and available moisture in the central Platte River Valley. Nebraska between 1980 and 1996. We also compared species richness and community similarity of breeding birds in sedge (Carex spp.) meadows and mesic grasslands. Densities of two species had a significant relationship with grazing and six of seven focal species had a significant relationship with available moisture. Bobolink (Dolichonyx oryzivorus) and Brown-headed Cowbird (Molothrus ater) densities were lower in grazed plots compared to ungrazed plots, whereas Red-winged Blackbird (Agelaius phoeniceus) densities were greater in sedge-meadow plots compared to mesic grassland plots. Bobolink, Dickcissel (Spiza americana). and Brown-headed Cowbird were negatively associated with available moisture with breeding densities peaking during the driest conditions. Our results suggest that wet conditions increase species richness for the community through addition of wetland-dependant and wetland-associated birds, but decrease densities of ground-nesting grassland birds in wet-meadow habitats, whereas dry conditions reduce species richness but increase the density of the avian assemblage. We propose that wet-meadow habitats serve as local refugia for grassland-nesting birds during local or regional droughts.

  20. Volcanic rocks and processes of the Mid-Atlantic Ridge rift valley near 36 ° 49′ N

    USGS Publications Warehouse

    Hekinian, R.; Moore, J.G.; Bryan, W.B.

    1976-01-01

    The above relations indicate that the diverse lava types were erupted from a shallow, zoned magma chamber from fissures distributed over the width of the inner rift valley and elongate parallel to it. Differentiation was accomplished by cooling and crystallization of plagioclase, olivine, and clinopyroxene toward the margins of the chamber. The centrally located hills were built by the piling up of frequent eruption of mainly primitive lavas which also are the youngest flows. In contrast smaller and less frequent eruptions of more differentiated lavas were exposed on both sides of the rift valley axis.

  1. Fretted Terrain Valleys

    NASA Technical Reports Server (NTRS)

    2004-01-01

    30 October 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows shallow tributary valleys in the Ismenius Lacus fretted terrain region of northern Arabia Terra. These valleys exhibit a variety of typical fretted terrain valley wall and floor textures, including a lineated, pitted material somewhat reminiscent of the surface of a brain. Origins for these features are still being debated within the Mars science community; there are no clear analogs to these landforms on Earth. This image is located near 39.9oN, 332.1oW. The picture covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the lower left.

  2. Magnetic Susceptibility and Mineral Zonations Controlled by Provenance in Loess along the Illinois and Central Mississippi River Valleys

    USGS Publications Warehouse

    Grimley, D.A.; Follmer, L.R.; McKay, E.D.

    1998-01-01

    Magnetic susceptibility (MS) patterns have proven useful for regional stratigraphic correlations of zones within thick, oxidized Peoria and Roxana Silts along the Illinois and Central Mississippi River valleys for more than 350 km. Variations in MS of C horizon loess are controlled by silt-sized magnetite content and are interpreted to reflect changes in sediment provenance due to fluctuations of the Superior and Lake Michigan glacier lobes and the diversion of the Mississippi River to its present course. Grain size distributions and scanning electron microscopic observations indicate that stratigraphic changes in MS are not significantly influenced by eolian sorting or diagenetic dissolution, respectively. Three compositional zones (lower, middle, and upper) are delineated within Peoria Silt which usually can be traced in the field by MS, the occurrence of clay beds, interstadial soils, and/or subtle color changes. These zones can be correlated with, but are generally of more practical use than, previously studied dolomite zones (McKay, 1977) or clay mineral zones (Frye et al., 1968). However, mineralogical analyses can help to substantiate zone boundaries when in question. MS and compositional zones may indirectly record a climatic signal, primarily through the effect that global cooling has had on ice lobe fluctuations in the Upper Mississippi drainage basin. ?? 1998 University of Washington.

  3. Geologic history of the Yosemite Valley

    USGS Publications Warehouse

    Matthes, Francois E.

    1930-01-01

    Projection of the longitudinal profiles of these hanging valleys forward to the axis of the Merced Canyon shows that they are closely accordant in height. Their profiles indicate a series of points on a former profile of the Merced with respect to which the side streams had graded their courses prior to the last uplift. This old profile can be extended upward into the glaciated part of the Merced Canyon above El Portal and even into the profoundly glaciated Yosemite Valley, accordant points being furnished by a number of hanging side valleys (due allowance being made for glacial erosion suffered by those valleys). However, not all the hanging valleys of the Yosemite region are accordant with this set. Several of them, including the upland valley of Yosemite Creek, constitute a separate set indicating another old profile of the Merced at a level 600 to 1,000 feet higher than the first. Others, including the hanging gulch of lower Bridalveil Creek, point to an old profile of the Merced about 1,200 feet lower than the first. There are thus three distinct sets of hanging valleys produced in three cycles of stream erosion. The valleys of the upper set, like those of the middle set, were left hanging as a result of rapid trenching by the Merced induced by an uplift of the range, there having been two such uplifts. Only the valleys of the lower set hang because of glacial deepening and widening of the Yosemite Valley, the cycle in which they were cut having been interrupted by the advent of the Pleistocene glaciers. They consequently indicate the preglacial depth of the Yosemite Valley. That depth, measured from the brow of El Capitan, was about 2,400 feet; measured from the rim at Glacier Point it was about 2,000 feet.

  4. Data for four geologic test holes in the Sacramento Valley, California

    USGS Publications Warehouse

    Berkstresser, C.F.; French, J.J.; Schaal, M.E.

    1985-01-01

    The report provides geological and geophysical data for four of seven test holes drilled as a part of the Central Valley Aquifer Project, which is part of the Regional Aquifer Systems Analysis. The holes were drilled with a rotary well drilling machine to depths of 900 feet in the southwestern part of the Sacramento Valley in Solano and Yolo Counties. Geologic data for each well include lithology, texture, color, character of the contact, sorting, rounding, and cementation, determined from cuttings, cores, and sidewall covers. Fifty cores, 3 feet long, were obtained from each hole, and from eight to fourteen sidewall cores were collected. Geophysical data include a dual-induction log, spherically focused log (SFL), compensated neutron-formation density log, gamma-ray log, and a caliper log. These data are presented in four tables and on four plates. (USGS)

  5. Natural heat storage in a brine-filled solar pond in the Tully Valley of central New York

    USGS Publications Warehouse

    Hayhurst, Brett; Kappel, William M.

    2014-01-01

    The Tully Valley, located in southern Onondaga County, New York, has a long history of unusual natural hydrogeologic phenomena including mudboils (Kappel, 2009), landslides (Tamulonis and others, 2009; Pair and others, 2000), landsurface subsidence (Hackett and others, 2009; Kappel, 2009), and a brine-filled sinkhole or “Solar pond” (fig. 1), which is documented in this report. A solar pond is a pool of salty water (brine) which stores the sun’s energy in the form of heat. The saltwater naturally forms distinct layers with increasing density between transitional zones (haloclines) of rapidly changing specific conductance with depth. In a typical solar pond, the top layer has a low salt content and is often times referred to as the upper convective zone (Lu and others, 2002). The bottom layer is a concentrated brine that is either convective or temperature stratified dependent on the surrounding environment. Solar insolation is absorbed and stored in the lower, denser brine while the overlying halocline acts as an insulating layer and prevents heat from moving upwards from the lower zone (Lu and others, 2002). In the case of the Tully Valley solar pond, water within the pond can be over 90 degrees Fahrenheit (°F) in late summer and early fall. The purpose of this report is to summarize observations at the Tully Valley brine-filled sinkhole and provide supplemental climate data which might affect the pond salinity gradients insolation (solar energy).

  6. 76 FR 22746 - Conecuh Valley Railway, LLC-Acquisition and Operation Exemption-Conecuh Valley Railroad Co., Inc.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-22

    ... Railway, LLC--Acquisition and Operation Exemption--Conecuh Valley Railroad Co., Inc. Conecuh Valley Railway, LLC (CVR), a noncarrier, has filed a verified notice of exemption under 49 CFR 1150.31 to acquire from Conecuh Valley Railroad Co., Inc. (COEH), and to operate [[Page 22747

  7. Compositions of Diverse Noachian Lithologies at Marathon Valley, Endeavour Crater Rim, Mars

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.; Gellert, Ralf; Yen, Albert S.; Ming, Douglas W.; Van Bommel, Scott; Farrand, William H.; Arvidson, Raymond E.; Rice, James W., Jr.

    2015-01-01

    Mars Exploration Rover Opportunity has been exploring Meridiani Planum for 11+ years, and is presently investigating the geology of rim segments of 22 km diameter, Noachian-aged Endeavour crater. The Alpha Particle X-ray Spectrometer has determined the compositions of a pre-impact lithology and impact breccias representing ejecta from the crater. Opportunity is now investigating the head (higher elevation, western end) of Marathon Valley. This valley cuts eastward through the central portion of the Cape Tribulation rim segment and provides a window into the lower stratigraphic record of the rim. At the head of Marathon Valley is a shallow (few 10s of cm), ovoid depression approximately 27×36 m in size, named Spirit of Saint Louis, that is surrounded by approximately 20-30 cm wide zone of more reddish rocks (red zone). Opportunity has just entered a region of Marathon Valley that shows evidence for Fe-Mg smectite in Compact Reconnaissance Imaging Spectrometer for Mars spectra indicating areally extensive and distinct lithologic units and/or styles of aqueous alteration. Rocks at the head of Marathon Valley and within Spirit of Saint Louis are breccias (valley-head rocks). In some areas, layering inside Spirit of Saint Louis appears continuous with the rocks outside. The valley-head rocks are of similar, generally basaltic composition. The continuity in composition, texture and layering suggest the valley-head rocks are coeval breccias, likely from the Endeavour impact. These local breccias are similar in non-volatile-element composition to breccias investigated elsewhere on the rim. Rocks within the red zone are like those on either side in texture, but have higher Al, Si and Ge, and lower S, Mn, Fe, Ni and Zn as compared to rocks on either side. The valley-head rocks have higher S than most Endeavour rim breccias, while red zone rocks are like those latter breccias in S. Patches within the rocks outside Spirit of Saint Louis have higher Al, Si and Ge indicating

  8. Hydrology and simulation of ground-water flow in Juab Valley, Juab County, Utah.

    USGS Publications Warehouse

    Thiros, Susan A.; Stolp, Bernard J.; Hadley, Heidi K.; Steiger, Judy I.

    1996-01-01

    Plans to import water to Juab Valley, Utah, primarily for irrigation, are part of the Central Utah Project. A better understanding of the hydrology of the valley is needed to help manage the water resources and to develop conjunctive-use plans.The saturated unconsolidated basin-fill deposits form the ground-water system in Juab Valley. Recharge is by seepage from streams, unconsumed irrigation water, and distribution systems; infiltration of precipitation; and subsurface inflow from consolidated rocks that surround the valley. Discharge is by wells, springs, seeps, evapotranspiration, and subsurface outflow to consolidated rocks. Ground-water pumpage is used to supplement surface water for irrigation in most of the valley and has altered the direction of groundwater flow from that of pre-ground-water development time in areas near and in Nephi and Levan.Greater-than-average precipitation during 1980-87 corresponds with a rise in water levels measured in most wells in the valley and the highest water level measured in some wells. Less-than average precipitation during 1988-91 corresponds with a decline in water levels measured during 1988-93 in most wells. Geochemical analyses indicate that the sources of dissolved ions in water sampled from the southern part of the valley are the Arapien Shale, evaporite deposits that occur in the unconsolidated basin-fill deposits, and possibly residual sea water that has undergone evaporation in unconsolidated basin-fill deposits in selected areas. Water discharging from a spring at Burriston Ponds is a mixture of about 70 percent ground water from a hypothesized flow path that extends downgradient from where Salt Creek enters Juab Valley and 30 percent from a hypothesized flow path from the base of the southern Wasatch Range.The ground-water system of Juab Valley was simulated by using the U.S. Geological Survey modular, three-dimensional, finite-difference, ground-water flow model. The numerical model was calibrated to simulate

  9. MX Siting Investigation. Water Resources Program. Volume II. Review Draft, Water Appropriations Hearing Presentation and Support Documentation, Dry Lake Valley, Nevada.

    DTIC Science & Technology

    1981-09-30

    will be required to de - liver the 651 gpm (41 l/s) needed for peak water use at the LSC. The existing Air Force test well at 3S-64E-12ca has been pumped...Valley is probably over 10,000 feet (3048 m) thick in the central part of the valley and is composed of alluvial fan, fluvial, playa , srl lacustrine...VALLEY T3.NSmIP STATION T E𔃾P SP. or SS. SILICA C AL C IU4 ACG. E5SILJ4 SCDIU I QANSA-SECT 5 6 C1 Ŕ VQ %;,. DES C CONE PH SOLIDS (5102) CA V$ A% 1 IN/6

  10. 75 FR 82127 - Culturally Significant Objects Imported for Exhibition Determinations: “Central Nigeria Unmasked...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-29

    ... DEPARTMENT OF STATE [Public Notice 7278] Culturally Significant Objects Imported for Exhibition Determinations: ``Central Nigeria Unmasked: Arts of the Benue River Valley'' SUMMARY: Notice is hereby given of... determine that the objects to be included in the exhibition ``Central Nigeria Unmasked: Arts of the Benue...

  11. Evaluating wildlife mortality hotspots, habitat connectivity and potential mitigation along US 287 and MT 87 in the Madison Valley, Montana : project summary report: 8217-001.

    DOT National Transportation Integrated Search

    2016-11-01

    The Madison Valley is situated in the Greater Yellowstone Ecosystem (GYE) and plays a key role in connecting this ecologicallyintact ecosystem to other intact areas of the Central Rockies, particularly the wildlands of central Idaho and the Selway-Bi...

  12. Grizzly Valley fault system, Sierra Valley, CA

    USGS Publications Warehouse

    Gold, Ryan; Stephenson, William; Odum, Jack; Briggs, Rich; Crone, Anthony; Angster, Steve

    2012-01-01

    The Grizzly Valley fault system (GVFS) strikes northwestward across Sierra Valley, California and is part of a network of active, dextral strike-slip faults in the northern Walker Lane (Figure 1). To investigate Quaternary motion across the GVFS, we analyzed high-resolution (0.25 m) airborne LiDAR data (Figure 2) in combination with six, high-resolution, P-wave, seismic-reflection profiles [Gold and others, 2012]. The 0.5- to 2.0-km-long seismic-reflection profiles were sited orthogonal to suspected tectonic lineaments identified from previous mapping and our analysis of airborne LiDAR data. To image the upper 400–700 m of subsurface stratigraphy of Sierra Valley (Figure 3), we used a 230-kg accelerated weight drop source. Geophone spacing ranged from 2 to 5 m and shots were co-located with the geophones. The profiles reveal a highly reflective, deformed basal marker that we interpret to be the top of Tertiary volcanic rocks, overlain by a 120- to 300-m-thick suite of subhorizontal reflectors we interpret as Plio-Pleistocene lacustrine deposits. Three profiles image the principle active trace of the GVFS, which is a steeply dipping fault zone that offsets the volcanic rocks and the basin fill (Figures 4 & 5).

  13. Topological Valley Currents in Gapped Dirac Materials

    NASA Astrophysics Data System (ADS)

    Lensky, Yuri D.; Song, Justin C. W.; Samutpraphoot, Polnop; Levitov, Leonid S.

    2015-06-01

    Gapped 2D Dirac materials, in which inversion symmetry is broken by a gap-opening perturbation, feature a unique valley transport regime. Topological valley currents in such materials are dominated by bulk currents produced by electronic states just beneath the gap rather than by edge modes. The system ground state hosts dissipationless persistent valley currents existing even when topologically protected edge modes are absent. Valley currents induced by an external bias are characterized by a quantized half-integer valley Hall conductivity. The undergap currents dominate magnetization and the charge Hall effect in a light-induced valley-polarized state.

  14. Stratigraphic sections of Middle Jurassic Entrade sandstone and related rocks from Salt Valley to Dewey Bridge in East-Central Utah

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    O'Sullivan, R.B.

    1981-01-01

    The San Rafael Group of Middle Jurassic age form extensive dip slopes on the north side of Salt Valley and crops out in bold cliffs from Salt Wash eastward to Dewey Bridge. In the San Rafael Swell about 70 km west of Salt Valley; the San Rafael Group consists in ascending order of Page Sandstone, Carmel Formation, Entrada Sandstone, and the Curtis and Summerville Formations. Fifteen stratigraphic sections are included on the map interpretation of the stratigraphy aids petroleum and natural gas investigations. (DP)

  15. Deglaciation chronology in the Mérida Andes from cosmogenic 10Be dating, (Gavidia valley, Venezuela)

    NASA Astrophysics Data System (ADS)

    Angel, Isandra; Audemard M., Franck A.; Carcaillet, Julien; Carrillo, Eduardo; Beck, Christian; Audin, Laurence

    2016-11-01

    In the Mérida Andes, a detailed deglaciation history reconstruction is difficult to achieve due to scattered deglaciation chronologies available. This paper contributes with 24 exposure ages of glacial landforms sampled in the Gavidia valley. Exposure ages were obtained based on terrestrial cosmogenic nuclide 10Be dating. Results indicate deglaciation mainly occurred between ∼21 ka and 16.5 ka and the complete deglaciation occurred at ∼16.0 ka. The glacier retreated in two different phases. The oldest one occurred since the LGM until middle OtD or the local climate event El Caballo Stadial. The youngest phase occurred at ages younger than ∼16.5 ka until complete deglaciation. A combination of topographic features and changes in the paleoclimate conditions at the end of the El Caballo Stadial seems leaded the fastest former glacier extinction. The topographic feature which seems contributed to the fastest glacier extinction was the low valley bottom slopes. In addition, exposure ages of the Gavidia valley were integrated with deglaciation chronologies from the central Mérida Andes to compare deglaciation histories. Asynchronous deglaciation histories were observed. Local paleotemperatures and paleoprecipitations contrasts, different valleys aspects, insolation and catchments steepness could explain different deglaciation histories.

  16. A landscape scale valley confinement algorithm: Delineating unconfined valley bottoms for geomorphic, aquatic, and riparian applications

    Treesearch

    David E. Nagel; John M. Buffington; Sharon L. Parkes; Seth Wenger; Jaime R. Goode

    2014-01-01

    Valley confinement is an important landscape characteristic linked to aquatic habitat, riparian diversity, and geomorphic processes. This report describes a GIS program called the Valley Confinement Algorithm (VCA), which identifies unconfined valleys in montane landscapes. The algorithm uses nationally available digital elevation models (DEMs) at 10-30 m resolution to...

  17. Graphene Nanobubbles as Valley Filters and Beam Splitters

    NASA Astrophysics Data System (ADS)

    Settnes, Mikkel; Power, Stephen R.; Brandbyge, Mads; Jauho, Antti-Pekka

    2016-12-01

    The energy band structure of graphene has two inequivalent valleys at the K and K' points of the Brillouin zone. The possibility to manipulate this valley degree of freedom defines the field of valleytronics, the valley analogue of spintronics. A key requirement for valleytronic devices is the ability to break the valley degeneracy by filtering and spatially splitting valleys to generate valley polarized currents. Here, we suggest a way to obtain valley polarization using strain-induced inhomogeneous pseudomagnetic fields (PMFs) that act oppositely on the two valleys. Notably, the suggested method does not involve external magnetic fields, or magnetic materials, unlike previous proposals. In our proposal the strain is due to experimentally feasible nanobubbles, whose associated PMFs lead to different real space trajectories for K and K' electrons, thus allowing the two valleys to be addressed individually. In this way, graphene nanobubbles can be exploited in both valley filtering and valley splitting devices, and our simulations reveal that a number of different functionalities are possible depending on the deformation field.

  18. 76 FR 51929 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To Delist the Valley...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-19

    ... shrub component of riparian forests and adjacent uplands along river corridors of the Central Valley... elderberry shrubs (Barr 1991, p. 4). The larvae hatch in a few days and bore into living stems that are at...

  19. The Long Valley Caldera GIS database

    USGS Publications Warehouse

    Battaglia, Maurizio; Williams, M.J.; Venezky, D.Y.; Hill, D.P.; Langbein, J.O.; Farrar, C.D.; Howle, J.F.; Sneed, M.; Segall, P.

    2003-01-01

    This database provides an overview of the studies being conducted by the Long Valley Observatory in eastern California from 1975 to 2001. The database includes geologic, monitoring, and topographic datasets related to Long Valley caldera. The CD-ROM contains a scan of the original geologic map of the Long Valley region by R. Bailey. Real-time data of the current activity of the caldera (including earthquakes, ground deformation and the release of volcanic gas), information about volcanic hazards and the USGS response plan are available online at the Long Valley observatory web page (http://lvo.wr.usgs.gov). If you have any comments or questions about this database, please contact the Scientist in Charge of the Long Valley observatory.

  20. Ground Motion in Central Mexico: A Comprehensive Analysis

    NASA Astrophysics Data System (ADS)

    Ramirez-Guzman, L.; Juarez, A.; Rábade, S.; Aguirre, J.; Bielak, J.

    2015-12-01

    This study presents a detailed analysis of the ground motion in Central Mexico based on numerical simulations, as well as broadband and strong ground motion records. We describe and evaluate a velocity model for Central Mexico derived from noise and regional earthquake cross-correlations, which is used throughout this research to estimate the ground motion in the region. The 3D crustal model includes a geotechnical structure of the Valley of Mexico (VM), subduction zone geometry, and 3D velocity distributions. The latter are based on more than 200 low magnitude (Mw < 4.5) earthquakes and two years of noise recordings. We emphasize the analysis on the ground motion in the Valley of Mexico originating from intra-slab deep events and temblors located along the Pacific coast. Also, we quantify the effects Trans-Mexican Volcanic Belt (TMVB) and the low-velocity deposits on the ground motion. The 3D octree-based finite element wave propagation computations, valid up to 1 Hz, reveal that the inclusion of a basin with a structure as complex as the Valley of Mexico dramatically enhances the regional effects induced by the TMVB. Moreover, the basin not only produces ground motion amplification and anomalous duration, but it also favors the energy focusing into zones of Mexico City where structures typically undergo high levels of damage.

  1. The environmental costs of mountaintop mining valley fill operations for aquatic ecosystems of the Central Appalachians.

    PubMed

    Bernhardt, Emily S; Palmer, Margaret A

    2011-03-01

    Southern Appalachian forests are recognized as a biodiversity hot spot of global significance, particularly for endemic aquatic salamanders and mussels. The dominant driver of land-cover and land-use change in this region is surface mining, with an ever-increasing proportion occurring as mountaintop mining with valley fill operations (MTVF). In MTVF, seams of coal are exposed using explosives, and the resulting noncoal overburden is pushed into adjacent valleys to facilitate coal extraction. To date, MTVF throughout the Appalachians have converted 1.1 million hectares of forest to surface mines and buried more than 2,000 km of stream channel beneath mining overburden. The impacts of these lost forests and buried streams are propagated throughout the river networks of the region as the resulting sediment and chemical pollutants are transmitted downstream. There is, to date, no evidence to suggest that the extensive chemical and hydrologic alterations of streams by MTVF can be offset or reversed by currently required reclamation and mitigation practices. © 2011 New York Academy of Sciences.

  2. Structural and lithologic study of Northern Coast Range and Sacramento Valley, California

    NASA Technical Reports Server (NTRS)

    Rich, E. I. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. Preliminary analysis of the data received has disclosed two potentially important northwest-trending systems of linear features within the Northern California Coast Ranges. A third system, which trends northeast, can be traced with great uncertainty across the alluviated part of the Sacramento Valley and into the foothills of the Sierra Nevada. These linear features may represent fault systems or zones of shearing. Of interest, although not yet verified, is the observation that some of the mercury concentrations and some of the geothermally active areas of California may be located at the intersection of the Central and the Valley Systems. One, perhaps two, stratigraphic unconformities within the Late Mesozoic sedimentary rocks were detected during preliminary examination of the imagery; however, more analysis is necessary in order to verify this preliminary interpretation. A heretofore unrecognized, large circular depression, about 15 km in diameter, was detected within the alluviated part of the Sacramento Valley. The depression is adjacent to a large laccolithic intrusion and may be geologically related to it. Changes in the photogeologic characteristics of this feature will continue to be monitored.

  3. Charcterization of meadow ecosystems based on watershed and valley segment/reach scale characteristics [chapter 7

    Treesearch

    Wendy Trowbridge; Jeanne C. Chambers; Dru Germanoski; Mark L. Lord; Jerry R. Miller; David G. Jewett

    2011-01-01

    Great Basin riparian meadows are highly sensitive to both natural and anthropogenic disturbance. As detailed in earlier chapters, streams in the central Great Basin have a natural tendency to incise due to their geomorphic history (Miller and others 2001, 2004). Anthropogenic disturbances, including overgrazing by livestock, mining activities, and roads in the valley...

  4. Characterization of VOC Emissions from Various Components of Dairy Farming and their effect on San Joaquin Valley Air Quality

    NASA Astrophysics Data System (ADS)

    Yang, M. M.; Meinardi, S.; Krauter, C.; Blake, D.

    2008-12-01

    The San Joaquin Valley Air Basin in Central California is classified by the U.S. Environmental Protection Agency (EPA) as a serious non-attainment area for health-based eight-hour federal ozone (smog) standard (1). In August 2005, the San Joaquin Valley Air Pollution Control District issued a report identifying dairies as a main source of Volatile Organic Compounds (VOCs) and fine particulate matter in the valley (2). Among these compounds, we have found that ethanol, methanol, acetone and acetaldehyde are produced in major quantities throughout the San Joaquin valley as by-products of yeast fermentation of silage and photochemical oxidation. These oxygenates, especially ethanol, play an important role in ozone (O3) formation within the valley. Three different types of sampling protocols were employed in order to determine the degree of enhancement of the four oxygenates in the valley air shed, as well as to determine their sources, emission profiles and emission rates. An assessment of the emissions of these oxygenates in the valley was achieved using data obtained on low altitude flights through the valley and from ground level samples collected thoughout the valley. The photochemical production of ozone was calculated for each of the four oxygenates and approximately one hundred other quantified VOCs. Based on the Maximum Incremental Reactivity (MIR) scale and concentrations of each oxygenate in the atmosphere, as much as 20% of O3 production in the valley is from ethanol and its photochemical by-product acetaldehyde. Our findings suggest that improvement to the valley air quality may be obtained by focusing on instituting new silage containment practices and regulations. 1. Lindberg, J. "Analysis of the San Joaquin Valley 2007 Ozone Plan." State of California Air Resources Board. Final Draft Staff Report. 5/30/2007. 2. Crow, D., executive director/APCO. "Air Pollution Control Officer's Determination of VOC Emisison Factors for Dairies." San Joaquin Valley Air

  5. 27 CFR 9.78 - Ohio River Valley.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Ohio River Valley. 9.78... River Valley. (a) Name. The name of the viticultural area described in this section is “Ohio River Valley.” (b) Approved maps. The approved maps for determining the boundary of the Ohio River Valley...

  6. Valley dependent transport in graphene L junction

    NASA Astrophysics Data System (ADS)

    Chan, K. S.

    2018-05-01

    We studied the valley dependent transport in graphene L junctions connecting an armchair lead and a zigzag lead. The junction can be used in valleytronic devices and circuits. Electrons injected from the armchair lead into the junction is not valley polarized, but they can become valley polarized in the zigzag lead. There are Fermi energies, where the current in the zigzag lead is highly valley polarized and the junction is an efficient generator of valley polarized current. The features of the valley polarized current depend sensitively on the widths of the two leads, as well as the number of dimers in the armchair lead, because this number has a sensitive effect on the band structure of the armchair lead. When an external potential is applied to the junction, the energy range with high valley polarization is enlarged enhancing its function as a generator of highly valley polarized current. The scaling behavior found in other graphene devices is also found in L junctions, which means that the results presented here can be extended to junctions with larger dimensions after appropriate scaling of the energy.

  7. Down in the Valley.

    ERIC Educational Resources Information Center

    Salter, Linda Graef

    1999-01-01

    Describes the partnerships formed by West Valley Mission Community College District (California) with its surrounding Silicon Valley business community in an effort to benefit workforce development. Asserts that community colleges are uniquely positioned to provide a lifelong education that will yield a skilled workforce to meet the needs of…

  8. Ground-water resources of the Caguas-Juncos Valley, Puerto Rico

    USGS Publications Warehouse

    Puig, J.C.; Rodriguez, J.M.

    1993-01-01

    ?The Caguas-Juncos valley, which occupies an area of 35 square miles in east-central Puerto Rico, is underlain by the largely unconfined alluvial aquifer. Withdrawals from this aquifer for public water supply and for agricultural, industrial, and domestic water uses totalled about 3.0 million gallons per day in 1988. Some wells in the valley yield as much as 310 gallons per minute from the alluvial deposits along Rio Gurabo near Gurabo and near Juncos. Wells used at dairy farms in the area commonly yield about 30 gallons per minute. The potentiometric surface of the alluvial aquifer varies seasonally and generally is highest near the end of December and lowest in April. Transmissivity of the alluvial aquifer, estimated from specific capacity and slug test data, ranges from 65 to 4,800 feet squared per day. The estimated specific yield of the water-table is about 10 to 15 percent. The amount of water stored in the aquifer is estimated to be about 122,000 acre-feet. Analyses of ground-water samples revealed the presence of two distinct problems-- high natural concentrations of iron and manganese, and localized areas of human- related contamination scattered throughout the valley. The ground water is a calcium-bicarbonate type and typically has dissolved solids concentrations of less than 500 milligrams per liter.

  9. Hazardous Waste Cleanup: West Valley Demonstration Project USDOE in West Valley, New York

    EPA Pesticide Factsheets

    The U.S. Department of Energy's West Valley Demonstration Project is located at 10282 Rock Spring Road in West Valley, New York. This is a 167 acre, Department of Energy (DOE)-operated portion of a 3,300-acre site owned by the New York State Energy

  10. 75 FR 18499 - The Effects of Mountaintop Mines and Valley Fills on Aquatic Ecosystems of the Central...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-12

    ... environmental permitting requirements for Appalachian mountaintop removal and other surface coal mining projects.../guidance/mining.html ). Both documents will be reviewed by an independent review panel convened by EPA's... the state of the science on the ecological impacts of Mountaintop Mining and Valley Fill (MTM-VF...

  11. Inflation of Long Valley caldera, California, Basin and Range strain, and possible Mono Craters dike opening from 1990-94 GPS surveys

    USGS Publications Warehouse

    Marshall, G.A.; Langbein, J.; Stein, R.S.; Lisowski, M.; Svarc, J.

    1997-01-01

    Five years of annual Global Positioning System (GPS) surveys of a network centered on Long Valley, California, constrain displacement rates for these stations relative to a central station in the network. These observations are consistent with recent models of resurgent dome inflation in Long Valley (Langbein et al., 1995) and have sufficient signal to detect the presence of Basin and Range strain in the Long Valley region. The data also allow for the possibility of dike inflation beneath the Mono Craters; dike intrusion is consistent with the Mono Craters' recent geologic history of ash eruptions, with seismic tomography, leveling data, and geologic studies of these volcanic domes and flows. Copyright 1997 by the American Geophysical Union.

  12. Evidence of spatial and temporal slip partitioning in the northern Central Nevada Seismic Belt from ground-based imaging of offset landforms

    NASA Astrophysics Data System (ADS)

    Gold, P. O.; Cowgill, E.; Kreylos, O.

    2010-12-01

    Measurements derived from high-resolution terrestrial LiDAR (t-Lidar) surveys of landforms displaced during the 16 December 1954 Mw 6.8 Dixie Valley earthquake in central Nevada confirm the absence of historical strike slip north of latitude 39.5°N. This conclusion has implications for the effect of stress changes on the spatial and temporal evolution of the central Nevada seismic belt. The Dixie Valley fault is a low-angle, east-dipping, range-bounding normal fault located in the central-northern reach of the central Nevada seismic belt (CNSB), a ~N-S trending group of historical ruptures that may represent a migration of northwest trending right-lateral Pacific-North American plate motion into central Nevada. Migration of a component of right slip eastward from the eastern California shear zone/Walker lane to the CNSB is supported by the presence of pronounced right-lateral motion observed in most of the CNSB earthquakes south of the Dixie Valley fault and by GPS data spanning the CNSB. Such eastward migration and northward propagation of right-slip into the CNSB predicts a component of lateral slip on the Dixie Valley fault. However, landforms offsets have previously been reported to indicate only purely normal slip in the 1954 Dixie Valley event. To check the direction of motion during the Dixie Valley earthquake using higher precision methods than previously employed, we collected t-LiDAR data to quantify displacements of two well-preserved debris flow chutes separated along strike by ~10 km and at locations where the local fault strike diverges by >10° from the regional strike. Our highest confidence measurements yield a horizontal slip vector azimuth of ~107° at both sites, orthogonal to the average regional fault strike of ~17°. Thus, we find no compelling evidence for regional lateral motion in our other measurements. This result indicates that continued northward propagation of right lateral slip from its diffuse termination at the northern end of the

  13. A statistical assessment of pesticide pollution in surface waters using environmental monitoring data: Chlorpyrifos in Central Valley, California.

    PubMed

    Wang, Dan; Singhasemanon, Nan; Goh, Kean S

    2016-11-15

    Pesticides are routinely monitored in surface waters and resultant data are analyzed to assess whether their uses will damage aquatic eco-systems. However, the utility of the monitoring data is limited because of the insufficiency in the temporal and spatial sampling coverage and the inability to detect and quantify trace concentrations. This study developed a novel assessment procedure that addresses those limitations by combining 1) statistical methods capable of extracting information from concentrations below changing detection limits, 2) statistical resampling techniques that account for uncertainties rooted in the non-detects and insufficient/irregular sampling coverage, and 3) multiple lines of evidence that improve confidence in the final conclusion. This procedure was demonstrated by an assessment on chlorpyrifos monitoring data in surface waters of California's Central Valley (2005-2013). We detected a significant downward trend in the concentrations, which cannot be observed by commonly-used statistical approaches. We assessed that the aquatic risk was low using a probabilistic method that works with non-detects and has the ability to differentiate indicator groups with varying sensitivity. In addition, we showed that the frequency of exceedance over ambient aquatic life water quality criteria was affected by pesticide use, precipitation and irrigation demand in certain periods anteceding the water sampling events. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Parkinson's Disease and Residential Exposure to Maneb and Paraquat From Agricultural Applications in the Central Valley of California

    PubMed Central

    Cockburn, Myles; Bronstein, Jeff; Zhang, Xinbo; Ritz, Beate

    2009-01-01

    Evidence from animal and cell models suggests that pesticides cause a neurodegenerative process leading to Parkinson's disease (PD). Human data are insufficient to support this claim for any specific pesticide, largely because of challenges in exposure assessment. The authors developed and validated an exposure assessment tool based on geographic information systems that integrated information from California Pesticide Use Reports and land-use maps to estimate historical exposure to agricultural pesticides in the residential environment. In 1998–2007, the authors enrolled 368 incident PD cases and 341 population controls from the Central Valley of California in a case-control study. They generated estimates for maneb and paraquat exposures incurred between 1974 and 1999. Exposure to both pesticides within 500 m of the home increased PD risk by 75% (95% confidence interval (CI): 1.13, 2.73). Persons aged ≤60 years at the time of diagnosis were at much higher risk when exposed to either maneb or paraquat alone (odds ratio = 2.27, 95% CI: 0.91, 5.70) or to both pesticides in combination (odds ratio = 4.17, 95% CI: 1.15, 15.16) in 1974–1989. This study provides evidence that exposure to a combination of maneb and paraquat increases PD risk, particularly in younger subjects and/or when exposure occurs at younger ages. PMID:19270050

  15. Subsurface Constraints on Late Cenozoic Basin Geometry in Northern Fish Lake Valley and Displacement Transfer Along the Northern Fish Lake Valley Fault Zone, Western Nevada

    NASA Astrophysics Data System (ADS)

    Mueller, N.; Kerstetter, S. R.; Katopody, D. T.; Oldow, J. S.

    2016-12-01

    The NW-striking, right-oblique Fish Lake Valley fault zone (FLVFZ) forms the northern segment of the longest active structure in the western Great Basin; the Death Valley - Furnace Creek - Fish Lake Valley fault system. Since the mid-Miocene, 50 km of right-lateral displacement is documented on the southern FLVFZ and much of that displacement was and is transferred east and north on active WNW left-lateral faults. Prior to the Pliocene, displacement was transferred east and north on a low-angle detachment. Displacement on the northern part of the FLVFZ continues and is transferred to a fanned array of splays striking (west to east) WNW, NNW, ENE and NNE. To determine the displacement budget on these structures, we conducted a gravity survey to determine subsurface basin morphology and its relation to active faults. Over 2450 stations were collected and combined with existing PACES and proprietary data for a total of 3388 stations. The data were terrain corrected and reduced to a 2.67 g/cm3 density to produce a residual complete Bouguer anomaly. The eastern part of northern Fish Lake Valley is underlain by several prominent gravity lows forming several sub-basins with maximum RCBA values ranging from -24 to -28 mGals. The RCBA was inverted for depth using Geosoft Oasis Montaj GM-SYS 3D modeling software. Density values for the inversion were constrained by lithologic and density logs from wells that penetrate the entire Cenozoic section into the Paleozoic basement. Best fitting gravity measurements taken at the wellheads yielded an effective density of 2.4 g/cm3 for the basin fill. Modeled basement depths range between 2.1 to 3 km. The sub-basins form an arc opening to the NW and are bounded by ENE and NNE faults in the south and NS to NNW in the north. At the northern end of the valley, the faults merge with ENE left-lateral strike slip faults of the Mina deflection, which carries displacement to NW dextral strike-slip faults of the central Walker Lane.

  16. Rift Valley Fever Virus

    USDA-ARS?s Scientific Manuscript database

    Rift Valley fever virus (RVFV) is a mosquito-transmitted virus or arbovirus that is endemic in sub-Saharan Africa. In the last decade, Rift Valley fever (RVF) outbreaks have resulted in loss of human and animal life, as well as had significant economic impact. The disease in livestock is primarily a...

  17. The hydrogeology of the Tully Valley, Onondaga County, New York: an overview of research, 1992-2012

    USGS Publications Warehouse

    Kappel, William M.

    2014-01-01

    Onondaga Creek begins approximately 15 miles south of Syracuse, New York, and flows north through the Onondaga Indian Nation, then through Syracuse, and finally into Onondaga Lake in central New York. Tully Valley is in the upper part of the Onondaga Creek watershed between U.S. Route 20 and the Valley Heads end moraine near Tully, N.Y. Tully Valley has a history of several unusual hydrogeologic phenomena that affected past land use and the water quality of Onondaga Creek; the phenomena are still present and continue to affect the area today (2014). These phenomena include mud volcanoes or mudboils, landslides, and land-surface subsidence; all are considered to be naturally occurring but may also have been influenced by human activity. The U.S. Geological Survey (USGS), in cooperation with the U.S. Environmental Protection Agency and the Onondaga Lake Partnership, began a study of the Tully Valley mudboils beginning in October 1991 in hopes of understanding (1) what drives mudboil activity in order to remediate mudboil influence on the water quality of Onondaga Creek, and (2) land-surface subsidence issues that have caused a road bridge to collapse, a major pipeline to be rerouted, and threatened nearby homes. Two years into this study, the 1993 Tully Valley landslide occurred just over 1 mile northwest of the mudboils. This earth slump-mud flow was the largest landslide in New York in more than 70 years (Fickies, 1993); this event provided additional insight into the geology and hydrology of the valley. As the study of the Tully Valley mudboils progressed, other unusual hydrogeologic phenomena were found within the Tully Valley and provided the opportunity to perform short-term, small-scale studies, some of which became graduate student theses—Burgmeier (1998), Curran (1999), Morales-Muniz (2000), Baldauf (2003), Epp (2005), Hackett, (2007), Tamulonis (2010), and Sinclair (2013). The unusual geology and hydrology of the Tully Valley, having been investigated for

  18. Uplift and magma intrusion at Long Valley caldera from InSAR and gravity measurements

    USGS Publications Warehouse

    Tizzani, Pietro; Battaglia, Maurizio; Zeni, Giovanni; Atzori, Simone; Berardino, Paolo; Lanari, Riccardo

    2009-01-01

    The Long Valley caldera (California) formed ~760,000 yr ago following the massive eruption of the Bishop Tuff. Postcaldera volcanism in the Long Valley volcanic field includes lava domes as young as 650 yr. The recent geological unrest is characterized by uplift of the resurgent dome in the central section of the caldera (75 cm in the past 33 yr) and earthquake activity followed by periods of relative quiescence. Since the spring of 1998, the caldera has been in a state of low activity. The cause of unrest is still debated, and hypotheses range from hybrid sources (e.g., magma with a high percentage of volatiles) to hydrothermal fluid intrusion. Here, we present observations of surface deformation in the Long Valley region based on differential synthetic aperture radar interferometry (InSAR), leveling, global positioning system (GPS), two-color electronic distance meter (EDM), and microgravity data. Thanks to the joint application of InSAR and microgravity data, we are able to unambiguously determine that magma is the cause of unrest.

  19. An evaluation of Skylab (EREP) remote sensing techniques applied to investigation of crustal structure. [Death Valley and Greenwater Valley (CA)

    NASA Technical Reports Server (NTRS)

    Bechtold, I. C. (Principal Investigator)

    1974-01-01

    The author has identified the following significant results. A study of Greenwater Valley indicates that the valley is bounded on the north and east by faults, on the south by a basement high, and on the west by the dip slope of the black mountains, movement of ground water from the valley is thus Movement of ground water from the valley is thus restricted, indicating the valley is a potential water reservoir.

  20. Three-thrust fault system at the plate suture of arc-continent collision in the southernmost Longitudinal Valley, eastern Taiwan

    NASA Astrophysics Data System (ADS)

    Lee, J.; Chen, H.; Hsu, Y.; Yu, S.

    2013-12-01

    Active faults developed into a rather complex three-thrust fault system at the southern end of the narrow Longitudinal Valley in eastern Taiwan, a present-day on-land plate suture between the Philippine Sea plate and Eurasia. Based on more than ten years long geodetic data (including GPS and levelling), field geological investigation, seismological data, and regional tomography, this paper aims at elucidating the architecture of this three-thrust system and the associated surface deformation, as well as providing insights on fault kinematics, slip behaviors and implications of regional tectonics. Combining the results of interseismic (secular) horizontal and vertical velocities, we are able to map the surface traces of the three active faults in the Taitung area. The west-verging Longitudinal Valley Fault (LVF), along which the Coastal Range of the northern Luzon arc is thrusting over the Central Range of the Chinese continental margin, braches into two active strands bounding both sides of an uplifted, folded Quaternary fluvial deposits (Peinanshan massif) within the valley: the Lichi fault to the east and the Luyeh fault to the west. Both faults are creeping, to some extent, in the shallow surface level. However, while the Luyeh fault shows nearly pure thrust type, the Lichi fault reveals transpression regime in the north and transtension in the south end of the LVF in the Taitung plain. The results suggest that the deformation in the southern end of the Longitudinal Valley corresponds to a transition zone from present arc-collision to pre-collision zone in the offshore SE Taiwan. Concerning the Central Range, the third major fault in the area, the secular velocities indicate that the fault is mostly locked during the interseismic period and the accumulated strain would be able to produce a moderate earthquake, such as the example of the 2006 M6.1 Peinan earthquake, expressed by an oblique thrust (verging toward east) with significant left-lateral strike slip

  1. Effect of Acorn Planting Depth on Depredation, Emergence, and Survival of Valley and Blue Oak

    Treesearch

    William D. Tietje; Sherryl L. Nives; Jennifer A. Honig; William H. Weitkamp

    1991-01-01

    During 1989 in east-central San Luis Obispo County, California, we studied the relationship of valley oak (Quercus lobata) and blue oak (Q. douglasii) acorn planting depth and number of acorns per planting site to acorn depredation, seedling emergence, survival, and height. Acorns were planted at three depths (1.3, 5.1, and 10.2 cm...

  2. 27 CFR 9.154 - Chiles Valley.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Chiles Valley. (a) Name. The name of the viticultural area described in this section is “Chiles Valley... viticultural area are four 1:24,000 Scale U.S.G.S. topography maps. They are titled: (1) St. Helena, CA 1960 photorevised 1980; (2) Rutherford, CA 1951 photorevised 1968; (3) Chiles Valley, CA 1958 photorevised 1980; (4...

  3. Microscopic Identification of Prokaryotes in Modern and Ancient Halite, Saline Valley and Death Valley, California

    NASA Astrophysics Data System (ADS)

    Schubert, Brian A.; Lowenstein, Tim K.; Timofeeff, Michael N.

    2009-06-01

    Primary fluid inclusions in halite crystallized in Saline Valley, California, in 1980, 2004-2005, and 2007, contain rod- and coccoid-shaped microparticles the same size and morphology as archaea and bacteria living in modern brines. Primary fluid inclusions from a well-dated (0-100,000 years), 90 m long salt core from Badwater Basin, Death Valley, California, also contain microparticles, here interpreted as halophilic and halotolerant prokaryotes. Prokaryotes are distinguished from crystals on the basis of morphology, optical properties (birefringence), and uniformity of size. Electron micrographs of microparticles from filtered modern brine (Saline Valley), dissolved modern halite crystals (Saline Valley), and dissolved ancient halite crystals (Death Valley) support in situ microscopic observations that prokaryotes are present in fluid inclusions in ancient halite. In the Death Valley salt core, prokaryotes in fluid inclusions occur almost exclusively in halite precipitated in perennial saline lakes 10,000 to 35,000 years ago. This suggests that trapping and preservation of prokaryotes in fluid inclusions is influenced by the surface environment in which the halite originally precipitated. In all cases, prokaryotes in fluid inclusions in halite from the Death Valley salt core are miniaturized (<1 μm diameter cocci, <2.5 μm long, very rare rod shapes), which supports interpretations that the prokaryotes are indigenous to the halite and starvation survival may be the normal response of some prokaryotes to entrapment in fluid inclusions for millennia. These results reinforce the view that fluid inclusions in halite and possibly other evaporites are important repositories of microbial life and should be carefully examined in the search for ancient microorganisms on Earth, Mars, and elsewhere in the Solar System.

  4. Valley Vortex States in Sonic Crystals

    NASA Astrophysics Data System (ADS)

    Lu, Jiuyang; Qiu, Chunyin; Ke, Manzhu; Liu, Zhengyou

    2016-03-01

    Valleytronics is quickly emerging as an exciting field in fundamental and applied research. In this Letter, we study the acoustic version of valley states in sonic crystals and reveal a vortex nature of such states. In addition to the selection rules established for exciting valley polarized states, a mimicked valley Hall effect of sound is proposed further. The extraordinary chirality of valley vortex states, detectable in experiments, may open a new possibility in sound manipulations. This is appealing to scalar acoustics that lacks a spin degree of freedom inherently. In addition, the valley selection enables a handy way to create vortex matter in acoustics, in which the vortex chirality can be controlled flexibly. Potential applications can be anticipated with the exotic interaction of acoustic vortices with matter, such as to trigger the rotation of the trapped microparticles without contact.

  5. Topological Valley Transport in Two-dimensional Honeycomb Photonic Crystals.

    PubMed

    Yang, Yuting; Jiang, Hua; Hang, Zhi Hong

    2018-01-25

    Two-dimensional photonic crystals, in analogy to AB/BA stacking bilayer graphene in electronic system, are studied. Inequivalent valleys in the momentum space for photons can be manipulated by simply engineering diameters of cylinders in a honeycomb lattice. The inequivalent valleys in photonic crystal are selectively excited by a designed optical chiral source and bulk valley polarizations are visualized. Unidirectional valley interface states are proved to exist on a domain wall connecting two photonic crystals with different valley Chern numbers. With the similar optical vortex index, interface states can couple with bulk valley polarizations and thus valley filter and valley coupler can be designed. Our simple dielectric PC scheme can help to exploit the valley degree of freedom for future optical devices.

  6. Geology and ground-water resources of the Deer Lodge Valley, Montana

    USGS Publications Warehouse

    Konizeski, Richard L.; McMurtrey, R.G.; Brietkrietz, Alex

    1968-01-01

    The Deer Lodge Valley is a basin trending north-south within Powell, Deer Lodge, and Silver Bow Counties in west-central Montana, near the center of the Northern Rocky Mountains physiographic province. It trends northward between a group of relatively low, rounded mountains to the east and the higher, more rugged Flint Creek Range to the west. The Clark Fork and its tributaries drain the valley in a northerly direction. The climate is semiarid and is characterized by long cold winters and short cool summers. Agriculture and ore refining are the principal industries. Both are dependent on large amounts of water. The principal topographic features are a broad lowland, the Clark Fork flood plain, bordered by low fringing terraces that are in turn bordered by broad, high terraces, which slope gently upward to the mountains. The high terraces have been mostly obscured in the south end of the valley by erosion and by recent deposition of great coalescent fans radiating outward frown the mouths of various tributary canyons. The mountains east of the Deer Lodge Valley are formed mostly of Cretaceous sedimentary and volcanic rocks and a great core of Upper Cretaceous to lower Tertiary granitic rocks; those west of the valley are formed of Precambrian to Cretaceous sedimentary rocks and a core of lower Tertiary granitic rocks. Field relationships, gravimetric data, and seismic data indicate that the valley is a deep graben, which formed in early Tertiary time after emplacement of the Boulder and Philipsburg batholiths. During the Tertiary Period the valley was partly filled to a maximum depth of more than 5,500 feet with erosional detritus that came from the surrounding mountains and was interbedded with minor amounts of volcanic ejecta. This material accumulated in a great variety of local environments. Consequently the resultant deposits are of extremely variable lithology in lateral and vertical sequence. The deposits grade from unconsolidated to well-cemented and from

  7. Quaternary Sedimentary and Geomorphic History of River Valleys in the Lake Titicaca Basin, Peru and Bolivia

    NASA Astrophysics Data System (ADS)

    Rigsby, C. A.; Farabaugh, R. L.; Baker, P. A.

    2002-12-01

    Lacustrine sediments have become important archives of paleoclimatic history in the tropical Andes of South America. The history of lake level of Lake Titicaca (LT) has played a central role in these reconstructions. Here we report on our ongoing studies of the late Quaternary sedimentary and geomorphic histories of two of the major tributaries to LT (the Rios Ramis and Ilave) and on our earlier studies of LT's only outlet (the Rio Desaguadero). The strata and fluvial terraces in these valleys record large-scale aggradation and downcutting events that are apparently correlative with both climate changes in the LT basin and local complex response mechanisms (changes in sediment source, topographic variability, etc.). Both the Ramis and Ilave valleys have 5 terrace tracts, ranging from less than 1 m to approximately 53 m above the river level and occurring as both paired and unpaired tracts and as cut-fill, fill-, and strath terraces. The Rio Desaguadero valley has 4, locally paired, cut-fill and fill terrace tracts that range in height from approximately 2 m to 40 m above river level. In all three valleys, the terraces are underlain by meandering- and braided-river sands and gravels and by lacustrine muds. Radiocarbon dates from the Ilave and Desaguadero valleys suggest that strata in these valleys aggraded during periods of high or rising levels of LT, high or increasing sedimentation rates in the Rio Ilave delta, high (but variable) regional precipitation, and lacustrine sedimentation in the upstream-most reaches of the Rio Desaguadero valley. These same strata were downcut during periods of low or falling levels of LT, low or rapidly decreasing sedimentation rates in the Rio Ilave delta, and lower regional precipitation and runoff. In all three valleys, aggradational periods are punctuated by equilibrium periods of soil formation, downcutting events are episodic, and the most recent events are aggradation and subsequent downcutting of a low, young fill

  8. Estimating Strain Accumulation in the New Madrid and Wabash Valley Seismic Zones

    NASA Astrophysics Data System (ADS)

    Craig, T. J.; Calais, E.

    2014-12-01

    The mechanical behaviour -- and hence earthquake potential -- of faults in continental interiors is a question of critical importance for the resultant seismic hazard, but no consensus has yet been reached on this controversial topic. The debate has focused on the central and eastern United States, in particular the New Madrid Seismic Zone, struck by three magnitude 7 or greater earthquakes in 1811--1812, and to a lesser extent the Wabash Valley Seismic Zone just to the north. A key aspect of this issue is the rate at which strain is currently accruing on those faults in the plate interior, a quantity that remains debated. Understanding if the present-day strain rates indicate sufficient motion to account for the historical and paleoseismological earthquakes by steady-state fault behaviour, or if strain accumulation is time-dependent in this area, is critical for investigating the causative process driving this seismicity in the plate interior, and how regional strain reflects the interplay between stresses arising from different geological processes. Here we address this issue with an analysis of up to 14 years of continuous GPS data from a network of 200 sites in the central United States centred on the New Madrid and Wabash Valley seismic zones. We find that high-quality sites in these regions show motions that are consistently within the 95% confidence limit of zero deformation relative to a rigid background. These results place an upper bound on regional strain accrual of 0.2 mm/yr and 0.5 mm/yr in the New Madrid and Wabash Valley Seismic Zones, respectively. These results, together with increasing evidence for temporal clustering and spatial migration of earthquake sequences in continental interiors, indicate that either tectonic loading rates or fault properties vary with time in the NMSZ and possibly plate-wide.

  9. Structural and lithographic study of northern coast ranges and Sacramento Valley, California

    NASA Technical Reports Server (NTRS)

    Rich, E. I. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. The analysis of the ERTS data has disclosed three potentially important linear systems within the northern coast ranges and Sacramento Valley, California. A preliminary geomorphic analysis of the northern coast ranges discloses that the geomorphic characteristics of the area underlain by the Coastal system are much different from those associated with the Central system in the core of the Coast Ranges. Within the Coastal system, or Coastal belt, the drainage networks are moderately fine-textured and have moderately high density. The area associated with the Central system seems to be underlain by an heterogeneous assemblage of rock types which vary in their resistance to erosion. The boundary between the Coastal and Central geomorphic regions is poorly defined and, in a few places, the two regions can be separated only approximately.

  10. Water-resources appraisal of the Wet Mountain Valley, in parts of Custer and Fremont counties, Colorado

    USGS Publications Warehouse

    Londquist, C.J.; Livingston, R.K.

    1978-01-01

    The Wet Mountain Valley is an intermontane trough filled to a depth of at least 6,700 feet with unconsolidated deposits. Ground water occurs under both artesian and water-table conditions within the basin-fill aquifer and ground-water moverment is toward Grape and Texas Creeks. The depth to the water table is less than 10 feet in an area of about 40 square miles along the central part of the valley and is less than 100 feet in most of the remainder of the valley. Ground water stored in the upper 200 feet of saturated basin-fill sediments is estimated to total 1.5 million acre-feet. Yields greater than 50 gallons per minute generally can be expected from wells in the central part of the basin-fill aquifer, and yields less than 50 gallons per minute are generally reported from wells around the edge of the basin-fill aquifer. Yields of wells in the mountainous areas are generally less than 20 gallons per minute. Most streamflow occurs as a result of snowmelt runoff during June and July. The long-term annual runoff at seven stations ranges from an estimated 0.02 cubic foot per second per square mile to an estimated 1.17 cubic feet per second per square mile, generaly increasing with station altitude. Generalized annyal water budgets for two areas in the Wet Mountain Valley indicate that surface-water outflow is only 7 to 11 percent of the total water supply from precipitation and other sources. The remaining water is lost to the atmosphere by evapotranspiration. The quality of both the surface and ground water is generally within the recommended limits for drinking water set by the U.S. Public Health Service. (Woodard-USGS)

  11. Optical tuning of electronic valleys (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Sie, Edbert J.; Gedik, Nuh

    2017-02-01

    Monolayer transition-metal dichalcogenides such as MoS2 and WS2 are prime examples of atomically thin semiconducting crystals that exhibit remarkable electronic and optical properties. They have a pair of valleys that can serve as a new electronic degree of freedom, and these valleys obey optical selection rules with circularly polarized light. Here, we discuss how ultrafast laser pulses can be used to tune their energy levels in a controllable valley-selective manner. The energy tunability is extremely large, comparable to what would be obtained using a hundred Tesla of magnetic field. We will also show that such valley tunability can be performed while we effectively manipulate the valley selection rules. Finally, we will explore the prospect of using this technique through photoemission spectroscopy to create a new phase of matter called a valley Floquet topological insulator.

  12. Martian oceans, valleys and climate

    USGS Publications Warehouse

    Carr, M.H.

    2000-01-01

    The new Mars Global Surveyor altimetry shows that the heavily cratered southern hemisphere of Mars is 5 km higher that the sparely cratered plains of the northern hemisphere. Previous suggestions that oceans formerly occupied that northern plains as evidenced by shorelines are partly supported by the new data. A previously identified outer boundary has a wide range of elevations and is unlikely to be a shoreline but an inner contact with a narrow range of elevations is a more likely candidate. No shorelines are visible in the newly acquired, 2.5 metre/pixel imaging. Newly imaged valleys provide strong support for sustained or episodic flow of water across the Martian surface. A major surprise, however, is the near absence of valleys less than 100 m across. Martian valleys seemingly do not divide into ever smaller valleys as terrestrial valleys commonly do. This could be due to lack of precipitation or lack of surface runoff because of high infiltration rates. High erosion rates and supports warm climates and presence of large bodies of water during heavy bombardment. The climate history and fate of the water after heavy bombardment remain cotroversial.

  13. Structural and Functional Characteristics of Natural and Constructed Channels Draining a Reclaimed Mountaintop Removal and Valley Fill Coal Mine

    EPA Science Inventory

    Mountaintop removal and valley fill (MTR/VF) coal mining has altered the landscape of the Central Appalachian region in the USA. Among the changes are large-scale topographic recontouring, burial of headwater streams, and degradation of downstream water quality. The goals of our ...

  14. Modeling vadose zone processes during land application of food-processing waste water in California's Central Valley.

    PubMed

    Miller, Gretchen R; Rubin, Yoram; Mayer, K Ulrich; Benito, Pascual H

    2008-01-01

    Land application of food-processing waste water occurs throughout California's Central Valley and may be degrading local ground water quality, primarily by increasing salinity and nitrogen levels. Natural attenuation is considered a treatment strategy for the waste, which often contains elevated levels of easily degradable organic carbon. Several key biogeochemical processes in the vadose zone alter the characteristics of the waste water before it reaches the ground water table, including microbial degradation, crop nutrient uptake, mineral precipitation, and ion exchange. This study used a process-based, multi-component reactive flow and transport model (MIN3P) to numerically simulate waste water migration in the vadose zone and to estimate its attenuation capacity. To address the high variability in site conditions and waste-stream characteristics, four food-processing industries were coupled with three site scenarios to simulate a range of land application outcomes. The simulations estimated that typically between 30 and 150% of the salt loading to the land surface reaches the ground water, resulting in dissolved solids concentrations up to sixteen times larger than the 500 mg L(-1) water quality objective. Site conditions, namely the ratio of hydraulic conductivity to the application rate, strongly influenced the amount of nitrate reaching the ground water, which ranged from zero to nine times the total loading applied. Rock-water interaction and nitrification explain salt and nitrate concentrations that exceed the levels present in the waste water. While source control remains the only method to prevent ground water degradation from saline wastes, proper site selection and waste application methods can reduce the risk of ground water degradation from nitrogen compounds.

  15. Plasma cholinesterase levels of mountain plovers (Charadrius montanus) wintering in central California, USA

    USGS Publications Warehouse

    Iko, W.M.; Archuleta, A.S.; Knopf, F.L.

    2003-01-01

    Declines of over 60% in mountain plover (Charadrius montanus) populations over the past 30 years have made it a species of concern throughout its current range and a proposed species for listing under the U.S. Endangered Species Act. Wintering mountain plovers spend considerable time on freshly plowed agricultural fields where they may potentially be exposed to anticholinesterase pesticides. Because of the population status and wintering ecology of plovers, the objectives of our study were to use nondestructive methods to report baseline plasma cholinesterase (ChE) levels in free-ranging mountain plovers wintering in California, USA, and to assess whether sampled birds showed signs of ChE inhibition related to anticholinesterase chemical exposure. We compared plasma ChE activity for mountain plovers sampled from the Carrizo Plain (an area relatively free of anticholinesterase pesticide use) with similar measures for plovers from the Central Valley (where anticholinesterase pesticides are widely used). Analyses for ChE inhibition indicated that none of the plovers had been recently exposed to these chemicals. However, mean ChE levels of plovers from the Central Valley were significantly higher (32%) than levels reported for plovers from the Carrizo Plain. This result differs from our original assumption of higher exposure risk to mountain plovers in the Central Valley but does suggest that some effect is occurring in the ChE activity of mountain plovers wintering in California.

  16. Evidence for Late-Paleozoic brine migration in Cambrian carbonate rocks of the central and southern Appalachians: Implications for Mississippi Valley-type sulfide mineralization

    USGS Publications Warehouse

    Hearn, P.P.; Sutter, J.F.; Belkin, H.E.

    1987-01-01

    Many Lower Paleozoic limestones and dolostones in the Valley and Ridge province of the central and southern Appalachians contain 10 to 25 weight percent authigenic potassium feldspar. This was considered to be a product of early diagenesis, however, 40Ar 39Ar analyses of overgrowths on detrital K-feldspar in Cambrian carbonate rocks from Pennsylvania, Maryland, Virginia, and Tennessee yield Late Carboniferous-Early Permian ages (278-322 Ma). Simple mass balance calculations suggest that the feldspar could not have formed isochemically, but required the flux of multiple pore volumes of fluid through the rocks, reflecting regional fluid migration events during the Late-Paleozoic Alleghanian orogeny. Microthermometric measurements of fluid inclusions in overgrowths on detrital K-feldspar and quartz grains from unmineralized rocks throughout the study area indicate homogenization temperatures from 100?? to 200??C and freezing point depressions of -14?? to -18.5??C (18-21 wt.% NaCl equiv). The apparent similarity of these fluids to fluid inclusions in ore and gangue minerals of nearby Mississippi Valley-type (MVT) deposits suggests that the regional occurrences of authigenic K-feldspar and MVT mineralization may be genetically related. This hypothesis is supported by the discovery of authigenic K-feldspar intergrown with sphalerite in several mines of the Mascot-Jefferson City District, E. Tennessee. Regional potassic alteration in unmineralized carbonate rocks and localized occurrences of MVT mineralization are both explainable by a gravity-driven flow model, in which deep brines migrate towards the basin margin under a hydraulic gradient established during the Alleghanian orogeny. The authigenic K-feldspar may reflect the loss of K during disequilibrium cooling of the ascending brines. MVT deposits are probably localized manifestations of the same migrating fluids, occurring where the necessary physical and chemical traps are present. ?? 1987.

  17. Bayesian Nitrate Source Apportionment to Individual Groundwater Wells in the Central Valley by use of Nitrogen, Oxygen, and Boron Isotopic Tracers

    NASA Astrophysics Data System (ADS)

    Lockhart, K.; Harter, T.; Grote, M.; Young, M. B.; Eppich, G.; Deinhart, A.; Wimpenny, J.; Yin, Q. Z.

    2014-12-01

    Groundwater quality is a concern in alluvial aquifers underlying agricultural areas worldwide, an example of which is the San Joaquin Valley, California. Nitrate from land applied fertilizers or from animal waste can leach to groundwater and contaminate drinking water resources. Dairy manure and synthetic fertilizers are the major sources of nitrate in groundwater in the San Joaquin Valley, however, septic waste can be a major source in some areas. As in other such regions around the world, the rural population in the San Joaquin Valley relies almost exclusively on shallow domestic wells (≤150 m deep), of which many have been affected by nitrate. Consumption of water containing nitrate above the drinking water limit has been linked to major health effects including low blood oxygen in infants and certain cancers. Knowledge of the proportion of each of the three main nitrate sources (manure, synthetic fertilizer, and septic waste) contributing to individual well nitrate can aid future regulatory decisions. Nitrogen, oxygen, and boron isotopes can be used as tracers to differentiate between the three main nitrate sources. Mixing models quantify the proportional contributions of sources to a mixture by using the concentration of conservative tracers within each source as a source signature. Deterministic mixing models are common, but do not allow for variability in the tracer source concentration or overlap of tracer concentrations between sources. Bayesian statistics used in conjunction with mixing models can incorporate variability in the source signature. We developed a Bayesian mixing model on a pilot network of 32 private domestic wells in the San Joaquin Valley for which nitrate as well as nitrogen, oxygen, and boron isotopes were measured. Probability distributions for nitrogen, oxygen, and boron isotope source signatures for manure, fertilizer, and septic waste were compiled from the literature and from a previous groundwater monitoring project on several

  18. Knickpoints and Hanging Valleys of Licus Vallis, Mars

    NASA Astrophysics Data System (ADS)

    Goudge, T. A.; Fassett, C.

    2016-12-01

    Licus Vallis is a 350 km long valley system located along the dichotomy boundary on Mars. The main trunk of the valley is incised 200-700 m into the surrounding terrain. The valley heads at an outlet breach of a shallow, 30 km diameter impact crater, and is also fed by a system of tributaries incised into the plateau surrounding Licus Vallis. Many of the tributary valleys, as well as the main stem of the valley fed by the paleolake outlet, have profiles that are not smoothly graded, but rather have distinct reaches with concave downward topography. These sections are either knickpoints or hanging valleys that develop in response to changes in the effective local base level, changes in climate conditions during incision of the valley, or lithologic boundaries in the substrate. Here we present remote sensing observations from images and topography to test these competing hypotheses and further characterize the evolution of this large valley system. Slope-watershed area relationships for the tributaries and main trunk valley are used to distinguish between knickpoints and hanging valleys. Analysis of orbital images does not reveal any distinct layer above which knickpoints develop, and the elevation of knickpoints show no systematic trends that might be expected of a regional lithologic unit(s). Our preliminary results suggest that the distance of knickpoint retreat is correlated with the position of the tributary valley and not the watershed area. Downstream valleys have retreated the most, suggesting they have had the most time to adjust to lowering of the local base level associated with incision of the main valley. These results are most consistent with a wave of incision sweeping up the valley system as it adjusts to a low base level in the northern plains. This conclusion is also consistent with observations of the incision depth of Licus Vallis, which increases approximately linearly downstream. Understanding this signature of base level control on the incision

  19. Schooling Experiences of Central California Indian People across Generations

    ERIC Educational Resources Information Center

    Williams, Tara

    2012-01-01

    This exploratory study took a post-colonialist lens to record, examine and document schooling experiences of California Indian people across several generations representing three Central Valley tribes: the Mono, the Tachi Yokuts of Santa Rosa Rancheria, and the Tule River Tribe. Past and present perceptions of Indian schooling were elicited…

  20. Quaternary fluvial terraces of the Tiber Valley: geochronologic and geometric constraints on the back-arc magmatism-related uplift in central Italy.

    PubMed

    Marra, Fabrizio; Florindo, Fabio; Petronio, Carmelo

    2017-05-31

    Through a geomorphological study relying on statistically assessed classes of hilltop elevations, we reconstruct a suite of paleo-surfaces along the Tiber River Valley north of Rome that we identify as fluvial terraces formed by interplay between global sea-level fluctuations and regional upift. Using biostratigraphic constraints provided by marine through continental deposits of Santernian age, we recognize the oldest terrace in this area, corresponding to an early coastal plain of late Santernian-Emilian age. By assuming the simple chronological principle of a staircase geometry we correlate the sea-level highstands of MIS 21 through MIS 5 with the lowest eight paleo-surfaces. By plotting against time the cumulated terrace elevations and the average elevation of the Santernian coastline in the investigated area, we detect rates of uplift during the last 1.8 Ma. Two major pulses of uplift are recognized 0.86 through 0.5 Ma, and 0.25 Ma through the Present, which are interpreted as driven by the subduction process and uprising of metasomatized magma bodies on the Tyrrhenian Sea Margin of central Italy, superimposied on a smaller isostatic component of uplift.

  1. Solar central receiver reformer system for ammonia plants

    NASA Astrophysics Data System (ADS)

    1980-07-01

    An overview of a study to retrofit the Valley Nitrogen Producers, Inc., El Centro, California 600 ST/SD Ammonia Plant with Solar Central Receiver Technology is presented. The retrofit system consists of a solar central receiver reformer (SCRR) operating in parallel with the existing fossil fired reformer. Steam and hydrocarbon react in the catalyst filled tubes of the inner cavity receiver to form a hydrogen rich mixture which is the syngas feed for the ammonia production. The SCRR system will displace natural gas presently used in the fossil reformer combustion chamber.

  2. A regression model for the temporal development of soil pipes and associated gullies in the alluvial-fill valley of the Rio Puerco, central New Mexico

    NASA Technical Reports Server (NTRS)

    Condit, C. D.; Elston, W. E.

    1984-01-01

    On Mars, the association of gullied escarpments and chaotic terrain is evidence for failure and scarp retreat of poorly consolidated materials. Some martian gullies have no surface outlets and may have drained through subterranean channels. Similar features, though on a much smaller scale, can be seen in alluvium along terrestrial river banks in semiarid regions, such as the Rio Puerco Valley of central New Mexico. Many of the escarpments along the Rio Puerco are developing through formation of collapse gullies, which drain through soil pipes. Gully development can be monitored on aerial photographs taken in 1935, 1962, and 1980. A regression model was developed to quantify gully evolution over a known time span. Soil pipes and their associated collapse gullies make recognizable signatures on the air photos. The areal extent of this signature can be normalized to the scarp length of each pipe-gully system, which makes comparisons between systems possible.

  3. Christmas Valley Renewable Energy Assessment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Del Mar, Robert

    In partnership with the Oregon Military Department, the Department of Energy used the award to assess and evaluate renewable resources in a 2,622-acre location in Lake County, central Oregon, leading to future development of up to 200 MW of solar electricity. In partnership with the Oregon Military Department, the Department of Energy used the award to assess and evaluate renewable resources in a 2,622-acre location in Lake County, central Oregon, leading to future development of up to 200 MW of solar electricity. The Oregon Military Department (Military) acquired a large parcel of land located in south central Oregon. The landmore » was previously owned by the US Air Force and developed for an Over-the-Horizon Backscatter Radar Transmitter Facility, located about 10 miles east of the town of Christmas Valley. The Military is investigating a number of uses for the site, including Research and Development (R&D) laboratory, emergency response, military operations, developing renewable energy and related educational programs. One of the key potential uses would be for a large scale solar photovoltaic power plant. This is an attractive use because the site has excellent solar exposure; an existing strong electrical interconnection to the power grid; and a secure location at a moderate cost per acre. The project objectives include: 1. Site evaluation 2. Research and Development (R&D) facility analysis 3. Utility interconnection studies and agreements 4. Additional on-site renewable energy resources analysis 5. Community education, outreach and mitigation 6. Renewable energy and emergency readiness training program for veterans« less

  4. Magnetic control of valley pseudospin in monolayer WSe 2

    DOE PAGES

    Aivazian, G.; Gong, Zhirui; Jones, Aaron M.; ...

    2015-01-26

    Local energy extrema of the bands in momentum space, or valleys, can endow electrons in solids with pseudo-spin in addition to real spin 1-5. In transition metal dichalcogenides this valley pseudo-spin, like real spin, is associated with a magnetic moment1,6 which underlies the valley-dependent circular dichroism 6 that allows optical generation of valley polarization 7-9, intervalley quantum coherence 10, and the valley Hall effect 11. However, magnetic manipulation of valley pseudospin via this magnetic moment 12-13, analogous to what is possible with real spin, has not been shown before. Here we report observation of the valley Zeeman splitting and magneticmore » tuning of polarization and coherence of the excitonic valley pseudospin, by performing polarization-resolved magneto-photoluminescence on monolayer WSe 2. Our measurements reveal both the atomic orbital and lattice contributions to the valley orbital magnetic moment; demonstrate the deviation of the band edges in the valleys from an exact massive Dirac fermion model; and reveal a striking difference between the magnetic responses of neutral and charged valley excitons which is explained by renormalization of the excitonic spectrum due to strong exchange interactions.« less

  5. Spin and valley filter across line defect in silicene

    NASA Astrophysics Data System (ADS)

    Wang, Sake; Ren, Chongdan; Li, Yunfang; Tian, Hongyu; Lu, Weitao; Sun, Minglei

    2018-05-01

    We propose a new scheme to achieve an effective spin/valley filter in silicene with extended line defect on the basis of spin–valley coupling due to the intrinsic spin-orbit coupling (SOC). The transmission coefficient of the spin/valley states is seriously affected by the SOC. When a perpendicular magnetic field is applied on one side of the line defect, one valley state will experience backscattering, but the other valley will not; this leads to high valley polarization in all transmission directions. Moreover, the spin/valley polarization can be enhanced to 96% with the aid of a perpendicular electric field.

  6. Early Jurassic clay authigenesis in the Central Appalachian Valley and Ridge province; infiltration of surface-derived fluids during Pangean rifting

    NASA Astrophysics Data System (ADS)

    Lynch, E. A.; van der Pluijm, B.; Vennemann, T. W.

    2017-12-01

    The eastern margin of North America has a protracted and intricate tectonic history. The terminal collision of Gondwana and Laurentia in the late Paleozoic formed the Appalachian mountain belt, a trans-continental orogen that persisted for almost 100 million years until Mesozoic break-up of the supercontinent Pangea. A host of studies have targeted the evolution and migration of fluids through Appalachian crust in an effort to understand how fluid promotes mass and heat redistribution, and mediates crustal deformation, particularly during the assembly of Pangea. Folded clay units from the Central Appalachian Valley and Ridge province were sampled for stable and radiogenic isotope analysis. Separation of samples into different grain-size fractions characterizes detrital (host) and authigenic (neomineralized) clays. Stable H-isotope compositions reveal a systematic pattern with varying proportions of illite polytypes—the finer, younger fraction is D-depleted compared to the coarser, primarily detrital fraction. For each individual location, the H-isotopic composition of the fluid from which the authigenic population was grown is calculated. δDVSMOW of these fluids has a range from -77 to -52 ± 2 ‰, consistent with a surface-derived fluid source. The notably negative values for several samples indicates a meteoric composition of moderate to high elevation origin, suggesting that they are not connate waters, but instead preserve infiltration of fluids due to fracture-induced permeability. Key to this interpretation is 40Ar/39Ar-dating of a subset of these samples that reveals a post-orogenic age for authigenic clay mineralization in the Early Jurassic ( 180 Ma). These ages are evidence that surface fluid infiltration was unrelated to the Appalachian orogeny, but coeval with (upper) crustal extension from the initial break-up of Pangea and the emplacement of the Central Atlantic Magmatic Province.

  7. The hydrothermal system of Long Valley Caldera, California

    USGS Publications Warehouse

    Sorey, M.L.; Lewis, Robert Edward; Olmsted, F.H.

    1978-01-01

    Long Valley caldera, an elliptical depression covering 450 km 2 on the eastern front of the Sierra Nevada in east-central California, contains a hot-water convection system with numerous hot springs and measured and estimated aquifer temperatures at depths of 180?C to 280?C. In this study we have synthesized the results of previous geologic, geophysical, geochemical, and hydrologic investigations of the Long Valley area to develop a generalized conceptual and mathematical model which describes the gross features of heat and fluid flow in the hydrothermal system. Cenozoic volcanism in the Long Valley region began about 3.2 m.y. (million years) ago and has continued intermittently until the present time. The major event that resulted in the formation of the Long Valley caldera took place about 0.7 m.y. ago with the eruption of 600 km 3 or more of Bishop Tuff of Pleistocene age, a rhyolitic ash flow, and subsequent collapse of the roof of the magma chamber along one or more steeply inclined ring fractures. Subsequent intracaldera volcanism and uplift of the west-central part of the caldera floor formed a subcircular resurgent dome about 10 km in diameter surrounded by a moat containing rhyolitic, rhyodacitic, and basaltic rocks ranging in age from 0.5 to 0.05 m.y. On the basis of gravity and seismic studies, we estimate an aver- age thickness of fill of 2.4 km above the precaldera granitic and metamorphic basement rocks. A continuous layer of densely welded Bishop Tuff overlies the basement rocks, with an average thickness of 1.4 km; the fill above the welded Bishop Tuff consists of intercalated volcanic flows and tuffs and fluvial and lacustrine deposits. Assuming the average grain density of the fill is between 2.45 and 2.65 g/cm 3 , we calculate the average bulk porosity of the total fill as from 0.11 to 0.21. Comparison of published values of porosity of the welded Bishop Tuff exposed southeast of the caldera with calculated values indicates average bulk porosity

  8. 27 CFR 9.36 - McDowell Valley.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ....” (b) Approved maps. The appropriate map for determining the boundaries of the McDowell Valley... and the ridge line (highest elevation line) between the McDowell Creek Valley and the Dooley Creek Valley. (3) Then southeasterly along the ridge line (highest elevation line) to the intersection of the...

  9. 27 CFR 9.36 - McDowell Valley.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ....” (b) Approved maps. The appropriate map for determining the boundaries of the McDowell Valley... and the ridge line (highest elevation line) between the McDowell Creek Valley and the Dooley Creek Valley. (3) Then southeasterly along the ridge line (highest elevation line) to the intersection of the...

  10. Valley Near Nilus Chaos

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-504, 5 October 2003

    This August 2003 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a valley near Nilus Chaos, around 25.2oN, 80.3oW. The scene has a uniform albedo, indicating that all of the landforms are probably mantled by fine, bright dust. Dark streaks on the valley walls indicate places where recent dust avalanches have occurred. The ripple-like dune features on the valley floor were formed by wind, but today they are inactive and covered with dust. A few craters, created by impacting debris, have formed on the dunes, again attesting to their inactivity in the modern martian environment. The image covers an area 3 km (1.9 mi) wide; it is illuminated by sunlight from the lower left.

  11. Phylogeography of microbial phototrophs in the dry valleys of the high Himalayas and Antarctica.

    PubMed

    Schmidt, S K; Lynch, R C; King, A J; Karki, D; Robeson, M S; Nagy, L; Williams, M W; Mitter, M S; Freeman, K R

    2011-03-07

    High-elevation valleys in dry areas of the Himalayas are among the most extreme, yet least explored environments on Earth. These barren, rocky valleys are subjected to year-round temperature fluctuations across the freezing point and very low availability of water and nutrients, causing previous workers to hypothesize that no photoautotrophic life (primary producers) exists in these locations. However, there has been no work using modern biogeochemical or culture-independent molecular methods to test the hypothesis that photoautotrophs are absent from high Himalayan soil systems. Here, we show that although microbial biomass levels are as low as those of the Dry Valleys of Antarctica, there are abundant microbial photoautotrophs, displaying unexpected phylogenetic diversity, in barren soils from just below the permanent ice line of the central Himalayas. Furthermore, we discovered that one of the dominant algal clades from the high Himalayas also contains the dominant algae in culture-independent surveys of both soil and ice samples from the Dry Valleys of Antarctica, revealing an unexpected link between these environmentally similar but geographically very distant systems. Phylogenetic and biogeographic analyses demonstrated that although this algal clade is globally distributed to other high-altitude and high-latitude soils, it shows significant genetic isolation by geographical distance patterns, indicating local adaptation and perhaps speciation in each region. Our results are the first to demonstrate the remarkable similarities of microbial life of arid soils of Antarctica and the high Himalayas. Our findings are a starting point for future comparative studies of the dry valleys of the Himalayas and Antarctica that will yield new insights into the cold and dry limits to life on Earth.

  12. Predominance of Central Asian and European families among Mycobacterium tuberculosis isolates in Kashmir Valley, India.

    PubMed

    Bashir, Gulnaz; Wani, Tehmeena; Sharma, Pragya; Katoch, V M; Lone, Rubina; Shah, Azra; Katoch, Kiran; Kakru, D K; Chauhan, Devendra Singh

    2017-10-01

    As there are no data available regarding the strains of Mycobacterium tuberculosis circulating in Kashmir Valley, India, the current study aimed at describing the genetic diversity of M. tuberculosis strains in this region, by spoligotyping and 12-locus-based MIRU-VNTR typing (Mycobacterial Interspersed Repetitive Unit-Variable Number Tandem Repeat). Sputa from 207 smear positive cases with newly diagnosed pulmonary tuberculosis were subjected to culture for M. tuberculosis. Eighty-five isolates confirmed as M. tuberculosis were subjected to drug susceptibility testing and molecular typing by spoligotyping and MIRU-VNTRs. Drug susceptibility results of 72 isolates revealed 76.3% as fully sensitive while 5.5% as multidrug resistant (MDR). Spoligotyping of 85 isolates detected 42 spoligotypes with 50 isolates (58.8%) clustered into seven spoligotypes. SIT26/CAS1_Del was the major spoligotype (23, 27%) followed by SIT127/H4 (12, 14.1%); CAS lineage (37.6%) was predominant, followed by Haarlem (25.8%) and ill-defined T clade (23.5%). MIRU-VNTR analysis displayed 82 MIRU patterns from 85 strains, including 3 small clusters and 79 unique. MIRU 26 was found to be the most discriminatory locus. Kashmir Valley has CAS as the predominant lineage of M. tuberculosis similar to the rest of the Indian sub-continent, while it is peculiar in having Euro American lineages such as Haarlem and ill-defined T clade. Copyright © 2017 Tuberculosis Association of India. Published by Elsevier B.V. All rights reserved.

  13. Structural controls on the spatial distribution and geochemical composition of volcanism in a continental rift zone; an example from Owens Valley, eastern California

    NASA Astrophysics Data System (ADS)

    Haproff, P. J.; Yin, A.

    2014-12-01

    Bimodal volcanism is common in continental rift zones. Structural controls to the emplacement and compositions of magmas, however, are not well understood. To address this issue, we examine the location, age, and geochemistry of active volcanic centers, and geometry and kinematics of rift-related faults across the active transtensional Owens Valley rift zone. Building on existing studies, we postulate that the spatial distribution and geochemical composition of volcanism are controlled by motion along rift-bounding fault systems. Along-strike variation in fault geometry and characteristics of active volcanism allow us to divide Owens Valley into three segments: southern, northern, and central. The southern segment of Owens Valley is a simple shear, asymmetric rift bounded to the west by the east-dipping Sierra Nevada frontal fault (SNFF). Active vents of Coso volcanic field are distributed along the eastern rift shoulder and characterized by the eruption of bimodal lavas. The SNFF within this segment is low-angle and penetrates through the lithosphere and into the ductile asthenosphere, allowing for mantle-derived magma to migrate across the weakest part of the fault zone beneath the eastern rift shoulder. Magma thermally weakens wall rocks and eventually stalls in the crust where the melt develops a greater felsic component prior to eruption. The northern segment of Owens Valley displays similar structural geometry, as the west-dipping White Mountains fault (WMF) is listric at depth and offsets the crust and mantle lithosphere, allowing for vertical transport of magma and reservoir emplacement within the crust. Bimodal lavas periodically erupted in the Long Valley Caldera region along the western rift shoulder. The central segment of Owens Valley is a pure shear, symmetric graben generated by motion along the SNFF and WMF. The subvertical, right-slip Owens Valley fault (OVF) strikes along the axis of the valley and penetrates through the lithosphere into the

  14. 27 CFR 9.194 - San Antonio Valley.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... significance. (b) Approved Maps. The appropriate maps for determining the boundary of the San Antonio Valley...) Hames Valley, California, 1949, photorevised 1978; (2) Tierra Redonda Mountain, California, 1949... southeast corner of section 14, T23S, R9E, on the Hames Valley map; (2) From the beginning point, proceed...

  15. Morning Transition Tracer Experiments in a Deep Narrow Valley.

    NASA Astrophysics Data System (ADS)

    Whiteman, C. David

    1989-07-01

    Three sulfur hexafluoride atmospheric tracer experiments were conducted during the post-sunrise temperature inversion breakup period in the deep, narrow Brush Creek Valley of Colorado. Experiments were conducted under clear, undisturbed weather conditions.A continuous elevated tracer plume was produced along the axis of the valley before sunrise and the behavior of the plume during the inversion breakup period was detected down-valley from the release point using an array of radio-controlled sequential bag samplers, a vertical SF6 profiling system carried on a tethered balloon, two portable gas chromatographs operated on a sidewall of the valley, and a continuous real-time SF6 monitor operated from a research aircraft. Supporting meteorological data came primarily from tethered balloon profilers. The nocturnal elevated plume was carried and diffused in down-valley flows. After sunrise, convective boundary layers grew upward from the sunlit valley surfaces, fumigating the elevated plume onto the valley floor and sidewalls. Upslope flow developed in the growing convective boundary layers, carrying fumigated SF6 up the sidewalls and causing a compensating subsidence over the valley center. High post-sunrise SF6 concentrations were experienced on the northeast-facing sidewall of the northwest-southeast oriented valley as a result of cross-valley flow, which developed due to differential solar heating of the sidewalls. Reversal of the down-valley wind system brought air with lower SF6 concentrations into the lower valley.

  16. Structural and functional characteristics of natural and constructed channels draining a reclaimed mountaintop removal and valley fill coal mine

    EPA Science Inventory

    Mountaintop removal and valley fill (MTR/VF) coal mining has altered the landscape of the Central Appalachian region in the United States. The goals of this study were to 1) compare the structure and function of natural and constructed stream channels in forested and MTR/VF catch...

  17. NV PFA - Steptoe Valley

    DOE Data Explorer

    Jim Faulds

    2015-10-29

    All datasets and products specific to the Steptoe Valley model area. Includes a packed ArcMap project (.mpk), individually zipped shapefiles, and a file geodatabase for the northern Steptoe Valley 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.

  18. 27 CFR 9.27 - Lime Kiln Valley.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Lime Kiln Valley. 9.27... OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.27 Lime Kiln Valley. (a) Name. The name of the viticultural area described in this section is “Lime Kiln Valley...

  19. Valley Pearl’ table grape

    USDA-ARS?s Scientific Manuscript database

    Valley Pearl’ is an early to mid-season, white seedless table grape (Vitis vinifera L.) suitable for commercial table grape production where V. vinifera can be grown. Significant characteristics of ‘Valley Pearl’ are its high and consistent fruit production on spur pruned vines and large round berr...

  20. Extraction of Martian valley networks from digital topography

    NASA Technical Reports Server (NTRS)

    Stepinski, T. F.; Collier, M. L.

    2004-01-01

    We have developed a novel method for delineating valley networks on Mars. The valleys are inferred from digital topography by an autonomous computer algorithm as drainage networks, instead of being manually mapped from images. Individual drainage basins are precisely defined and reconstructed to restore flow continuity disrupted by craters. Drainage networks are extracted from their underlying basins using the contributing area threshold method. We demonstrate that such drainage networks coincide with mapped valley networks verifying that valley networks are indeed drainage systems. Our procedure is capable of delineating and analyzing valley networks with unparalleled speed and consistency. We have applied this method to 28 Noachian locations on Mars exhibiting prominent valley networks. All extracted networks have a planar morphology similar to that of terrestrial river networks. They are characterized by a drainage density of approx.0.1/km, low in comparison to the drainage density of terrestrial river networks. Slopes of "streams" in Martian valley networks decrease downstream at a slower rate than slopes of streams in terrestrial river networks. This analysis, based on a sizable data set of valley networks, reveals that although valley networks have some features pointing to their origin by precipitation-fed runoff erosion, their quantitative characteristics suggest that precipitation intensity and/or longevity of past pluvial climate were inadequate to develop mature drainage basins on Mars.

  1. Dynamics of Katabatic Winds in Colorado' Brush Creek Valley.

    NASA Astrophysics Data System (ADS)

    Vergeiner, I.; Dreiseitl, E.; Whiteman, C. David

    1987-01-01

    A method is proposed to evaluate the coupled mass, momentum and thermal energy budget equations for a deep valley under two-dimensional, steady-state flow conditions. The method requires the temperature, down- valley wind and valley width fields to be approximated by simple analytical functions. The vertical velocity field is calculated using the mass continuity equation. Advection terms in the momentum and energy equations are then calculated using finite differences computed on a vertical two-dimensional grid that runs down the valley's axis. The pressure gradient term in the momentum equation is calculated from the temperature field by means of the hydrostatic equation. The friction term is then calculated as a residual in the xmomentum equation, and the diabatic cooling term is calculated as a residual in the thermal energy budget equation.The method is applied to data from an 8-km-long segment of Colorado's; Brush Creek Valley on the night of 30-31 July 1982. Pressure decreased with distance down the peak on horizontal surfaces, with peak horizontal pressure gradients of 0.04 hPa km1. The valley mass budget indicated that subsidence was required in the valley to support calculated mean along-valley mass flux divergence. Peak subsidence rates on the order of 0.10 m s1 were calculated. Subsiding motions in the valley produced negative vertical down-valley momentum fluxes in the upper valley atmosphere, but produced positive down-valley momentum fluxes below the level of the jet. Friction, calculated as a residual in the x momentum equation, was negative, as expected on physical grounds. and attained reasonable quantitative values.The strong subsidence field in the stable valley atmosphere produced subsidence warming that was only partly counteracted by down-valley cold air advection. Strong diabatic cooling was therefore required in order to account for the weak net cooling of the valley atmosphere during the nighttime period when tethered balloon observations

  2. Fretted Terrain Valley in Coloe Fossae Region

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Figure 1 Click on image for larger version

    The image in figure 1 shows lineated valley fill in one of a series of enclosed, intersecting troughs known as Coloe (Choloe) Fossae. Lineated valley fill consists of rows of material in valley centers that are parallel to the valley walls. It is probably made of ice-rich material and boulders that are left behind when the ice-rich material sublimates. Very distinct rows can be seen near the south (bottom) wall of the valley. Lineated valley fill is thought to result from mass wasting (downslope movement) of ice-rich material from valley walls towards their centers. It is commonly found in valleys near the crustal dichotomy that separates the two hemispheres of Mars. The valley shown here joins four other valleys with lineated fill near the top left corner of this image. Their juncture is a topographic low, suggesting that the lineated valley fill from the different valleys may be flowing or creeping towards the low area (movement towards the upper left of the image). The valley walls appear smooth at first glance but are seen to be speckled with small craters several meters in diameter at HiRISE resolution (see contrast-enhanced subimage). This indicates that at least some of the wall material has been stable to mass wasting for some period of time. Also seen on the valley wall are elongated features shaped like teardrops. These are most likely slightly older craters that have been degraded due to potentially recent downhill creep. It is unknown whether the valley walls are shedding material today. The subimage is approximately 140 x 400 m (450 x 1280 ft).

    Image PSP_001372_2160 was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter spacecraft on November 11, 2006. The complete image is centered at 35.5 degrees latitude, 56.8 degrees East longitude. The range to the target site was 290.3 km (181

  3. Victor Valley College Agreement between the Victor Valley Community College District and the Victor Valley College California Teachers Association Chapter 1170. July 1989 - June 1992.

    ERIC Educational Resources Information Center

    Victor Valley Community Coll. District, Victorville, CA.

    The collective bargaining agreement between the Victor Valley College Board of Trustees and the Victor Valley College California Teachers Association/National Education Association is presented. This contract, covering the period from July 1989 through June 1992, deals with the following topics: bargaining agent recognition; district and…

  4. Ground-Water Occurrence and Movement, 2006, and Water-Level Changes in the Detrital, Hualapai, and Sacramento Valley Basins, Mohave County, Arizona

    USGS Publications Warehouse

    Anning, David W.; Truini, Margot; Flynn, Marilyn E.; Remick, William H.

    2007-01-01

    Ground-water levels for water year 2006 and their change over time in Detrital, Hualapai, and Sacramento Valley Basins of northwestern Arizona were investigated to improve the understanding of current and past ground-water conditions in these basins. The potentiometric surface for ground water in the Basin-Fill aquifer of each basin is generally parallel to topography. Consequently, ground-water movement is generally from the mountain front toward the basin center and then along the basin axis toward the Colorado River or Lake Mead. Observed water levels in Detrital, Hualapai, and Sacramento Valley Basins have fluctuated during the period of historic water-level records (1943 through 2006). In Detrital Valley Basin, water levels in monitored areas have either remained the same, or have steadily increased as much as 3.5 feet since the 1980s. Similar steady conditions or water-level rises were observed for much of the northern and central parts of Hualapai Valley Basin. During the period of historic record, steady water-level declines as large as 60 feet were found in wells penetrating the Basin-Fill aquifer in areas near Kingman, northwest of Hackberry, and northeast of Dolan Springs within the Hualapai Valley Basin. Within the Sacramento Valley Basin, during the period of historic record, water-level declines as large as 55 feet were observed in wells penetrating the Basin-Fill aquifer in the Kingman and Golden Valley areas; whereas small, steady rises were observed in Yucca and in the Dutch Flat area.

  5. Valley spin polarization of Tl/Si(111)

    NASA Astrophysics Data System (ADS)

    Stolwijk, Sebastian D.; Schmidt, Anke B.; Sakamoto, Kazuyuki; Krüger, Peter; Donath, Markus

    2017-11-01

    The metal/semiconductor hybrid system Tl/Si(111)-(1 ×1 ) exhibits a unique Tl-derived surface state with remarkable properties. It lies within the silicon band gap and forms spin-momentum-locked valleys close to the Fermi energy at the K ¯ and K¯' points. These valleys are completely spin polarized with opposite spin orientation at K ¯ and K¯' and show a giant spin splitting of more than 0.5 eV. We present a detailed preparation study of the surface system and demonstrate that the electronic valleys are extremely robust, surviving exposure to 100 L hydrogen and 500 L oxygen. We investigate the influence of additional Tl atoms on the spin-polarized valleys. By combining photoemission and inverse photoemission, we prove the existence of fully spin-polarized valleys crossing the Fermi level. Moreover, these metallic valleys carry opposite Berry curvature at K ¯ and K¯', very similar to WSe2, promising a large spin Hall effect. Thus, Tl/Si(111)-(1 ×1 ) possesses all necessary key properties for spintronic applications.

  6. Electrical valley filtering in transition metal dichalcogenides

    NASA Astrophysics Data System (ADS)

    Hsieh, Tzu-Chi; Chou, Mei-Yin; Wu, Yu-Shu

    2018-03-01

    This work investigates the feasibility of electrical valley filtering for holes in transition metal dichalcogenides. We look specifically into the scheme that utilizes a potential barrier to produce valley-dependent tunneling rates, and perform the study with both a k .p -based analytic method and a recursive Green's function-based numerical method. The study yields the transmission coefficient as a function of incident energy and transverse wave vector, for holes going through lateral quantum barriers oriented in either armchair or zigzag directions, in both homogeneous and heterogeneous systems. The main findings are the following: (1) The tunneling current valley polarization increases with increasing barrier width or height; (2) both the valley-orbit interaction and band structure warping contribute to valley-dependent tunneling, with the former contribution being manifest in structures with asymmetric potential barriers, and the latter being orientation dependent and reaching maximum for transmission in the armchair direction; and (3) for transmission ˜0.1 , a tunneling current valley polarization of the order of 10 % can be achieved.

  7. Observation of valley-dependent beams in photonic graphene.

    PubMed

    Deng, Fusheng; Sun, Yong; Wang, Xiao; Xue, Rui; Li, Yuan; Jiang, Haitao; Shi, Yunlong; Chang, Kai; Chen, Hong

    2014-09-22

    Valley-dependent propagation of light in an artificial photonic hexagonal lattice, akin to electrons in graphene, is investigated in microwave regime. Both numerical and experimental results show that the valley degeneracy in the photonic graphene is broken when the frequency is away from the Dirac point. The peculiar anisotropic wave transport property due to distinct valleys is analyzed using the equifrequency contours. More interestingly, the valley-dependent self-collimation and beam splitting phenomena are experimentally demonstrated with the armchair and zigzag interfaces, respectively. Our results confirm that there are two inequivalent Dirac points that lead to two distinct valleys in photonic graphene, which could be used to control the flow of light and might be used to carry information in valley polarized beam splitter, collimator or guiding device.

  8. 27 CFR 9.58 - Carmel Valley.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ....” (b) Approved maps. The approved maps for determining the boundary of the Carmel Valley viticultural... Ridge, Calif., dated 1956; and (5) Rana Creek, Calif., dated 1956. (c) Boundary. The Carmel Valley...

  9. 27 CFR 9.58 - Carmel Valley.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ....” (b) Approved maps. The approved maps for determining the boundary of the Carmel Valley viticultural... Ridge, Calif., dated 1956; and (5) Rana Creek, Calif., dated 1956. (c) Boundary. The Carmel Valley...

  10. Water resources of Parowan Valley, Iron County, Utah

    USGS Publications Warehouse

    Marston, Thomas M.

    2017-08-29

    Parowan Valley, in Iron County, Utah, covers about 160 square miles west of the Red Cliffs and includes the towns of Parowan, Paragonah, and Summit. The valley is a structural depression formed by northwest-trending faults and is, essentially, a closed surface-water basin although a small part of the valley at the southwestern end drains into the adjacent Cedar Valley. Groundwater occurs in and has been developed mainly from the unconsolidated basin-fill aquifer. Long-term downward trends in groundwater levels have been documented by the U.S. Geological Survey (USGS) since the mid-1950s. The water resources of Parowan Valley were assessed during 2012 to 2014 with an emphasis on refining the understanding of the groundwater and surface-water systems and updating the groundwater budget.Surface-water discharge of five perennial mountain streams that enter Parowan Valley was measured from 2013 to 2014. The total annual surface-water discharge of the five streams during 2013 to 2014 was about 18,000 acre-feet (acre-ft) compared to the average annual streamflow of about 22,000 acre-ft from USGS streamgages operated on the three largest of these streams from the 1940s to the 1980s. The largest stream, Parowan Creek, contributes more than 50 percent of the annual surface-water discharge to the valley, with smaller amounts contributed by Red, Summit, Little, and Cottonwood Creeks.Average annual recharge to the Parowan Valley groundwater system was estimated to be about 25,000 acre-ft from 1994 to 2013. Nearly all recharge occurs as direct infiltration of snowmelt and rainfall on the Markagunt Plateau east of the valley. Smaller amounts of recharge occur as infiltration of streamflow and unconsumed irrigation water near the east side of the valley on alluvial fans associated with mountain streams at the foot of the Red Cliffs. Subsurface flow from the mountain block to the east of the valley is a significant source of groundwater recharge to the basin-fill aquifer

  11. Red DIME: Dissecting the Bolshevik Liquidation Campaign in the Ferghana Valley Against the Basmachi Resistance

    DTIC Science & Technology

    2008-05-22

    affairs, declaring it their business to reshape, not just administer, the region.8 At first, the Bolshevik apparatchiks attempted to transform Central...providing an avenue for a breadwinner to feed his family. Simultaneously, this effort assisted the pivotal agriculture rehabilitation agenda, including the...nation. Granted, just about any border design would have been insufficient in dealing with the diverse ethnic composition of the Ferghana Valley

  12. Optical manipulation of valley pseduospin in 2D semiconductors

    NASA Astrophysics Data System (ADS)

    Ye, Ziliang

    Valley polarization associated with the occupancy in the energy degenerate but quantum mechanically distinct valleys in the momentum space closely resembles spin polarization and has been proposed as a pseudospin carrier for future quantum information technologies. Monolayers of transition metal dichalcogenide (TMDC) crystals, with broken inversion symmetry and large spin-orbital coupling, support robust valley polarization and therefore provide an important platform for studying valley-dependent physics. Besides optical excitation and photoluminescence detection, valley polarization has been electrically measured through the valley Hall effect and created through spin injection from ferromagnetic semiconductor contacts. Moreover, the energy degeneracy of the valley degree of freedom has been lifted by the optical Stark effect. Recently, we have demonstrated optical manipulation of valley coherence, i.e., of the valley pseudospin, by the optical Stark effect in monolayer WSe2. Using below-bandgap circularly polarized light, we rotated the valley pseudospin on the femtosecond time scale. Both the direction and speed of the rotation can be optically controlled by tuning the dynamic phase of excitons in opposite valleys. The pseudospin rotation was identified by changes in the polarization of the photoluminescence. In addition, by varying the time delay between the excitation and control pulses, we directly probed the lifetime of the intervalley coherence. Similar rotation levels have also been observed in static magneto-optic experiments. Our work presents an important step towards the full control of the valley degree of freedom in 2D semiconductors. The work was done in collaboration with Dr. Dezheng Sun and Prof. Tony F. Heinz.

  13. An Archean Geomagnetic Reversal in the Kaap Valley Pluton, South Africa

    PubMed

    Layer; Kroner; McWilliams

    1996-08-16

    The Kaap Valley pluton in South Africa is a tonalite intrusion associated with the Archean Barberton Greenstone Belt. Antipodal paleomagnetic directions determined from the central and marginal parts of the pluton record a geomagnetic reversal that occurred as the pluton cooled. The age of the reversal is constrained by an 40Ar/39Ar plateau age from hornblende at 3214 +/- 4 million years, making it the oldest known reversal. The data presented here suggest that Earth has had a reversing, perhaps dipolar, magnetic field since at least 3.2 billion years ago.

  14. Near-Surface Structure and Velocities of the Northeastern Santa Cruz Mountains and the Western Santa Clara Valley, California, From Seismic Imaging

    USGS Publications Warehouse

    Catchings, R.D.; Gandhok, G.; Goldman, M.R.; Steedman, Clare

    2007-01-01

    reservoirs, pipelines, and flood-protection facilities maintained by SCVWD. As one component of these joint studies, the USGS acquired an approximately 10-km-long, high-resolution, combined seismic reflection/refraction transect from the Santa Cruz Mountains to the central SCV in December 2000 (Figs. 1 and 2a,b). The overall seismic investigation of the western Santa Clara Valley also included an ~18-km-long, lower-resolution (~50-m sensor) seismic imaging survey from the central Santa Cruz Mountains to the central part of the valley (Fig. 1). Collectively, we refer to these seismic investigations as the 2000 western Santa Clara Seismic Investigations (SCSI). Results of the high-resolution investigation, referred to as SCSI-HR, are presented in this report, and Catchings et al. (2006) present results of the low-resolution investigation (SCSI-LR) in a separate report. In this report, we present data acquisition parameters, unprocessed and processed seismic data, and interpretations of the SCSI-HR seismic transect.

  15. Export of detritus and invertebrate from headwater streams: linking mountaintop removal and valley fill coal mining to downstream receiving waters

    EPA Science Inventory

    Mountaintop removal and valley fill (MTR/VF) coal mining has resulted in large scale alteration of the topography, reduced forest productivity, and burial of headwater streams in the U.S. Central Appalachians. Although MTR/VF coal mining has occurred for several decades and the ...

  16. Geology and ground water in Napa and Sonoma Valleys, Napa and Sonoma Counties, California

    USGS Publications Warehouse

    Kunkel, Fred; Upson, Joseph Edwin

    1960-01-01

    COIM3ists of interbedded deposits of unconsolidated gravel. sand, silt. and. locally, peat. These deposits underlie the flood plains and channels of the Napa River. Sonoma Creek, and their tributaries, low alluvial fans or plains graded to these streams. and the tidal marshlands. The older alluvium of Napa and Sonoma Valleys is composed of lenticular deposits of unconsolidated and poorly sorted clay, silt. sand. and gravel. Where exposed, claypan or hardpan soil is characteristically developed at the surface. The Huichica formation is composed of deformed continental beds consisting mostly of yellow silt with some interbedded lenses of silt and gravel, and silt and boulders. At the base are beds of redeposited volcanic material, silt, clay, and lenses of coarse gravel and boulders. The Glen Ellen fcrmation consists of alluvial clay, silt, sand, and gravel in clearly stratified but generally lenticular beds. The Sonoma volcanics constitute a thick and highly variate series of continental volcanic rocks, including andesite, basalt, and minor rhyolite flows and interbedded coarse- to fine-grained pyroclastic tuff and breccia, redeposited tuff and pumice, and diatomaceous mud, silt, and sand. A prominent body of rhyolite flows and tuff with some obsidian and perlitic glass, called the St. Helena rhyolite member, occurs in the upper part. Estimated ground-water pumpage for all uses in the year 1949-50 was about 5,600 acre-feet in Napa Valley and about 2,400 acre-feet in Sonoma Valley. Of this quantity the amounts pumped for irrigation were about 2,900 and 1,900 acre-feet, respectively. Water levels in wells in the central parts of the valleys range from a few feet above the land surface to about 50 feet below, with an average of about 25 feet. The quality of the water in most wells is satisfactory for domestic use and irrigation. Locally at the southern end of the valley some contamination of the native waters is caused by the movement of salty wate

  17. Origin of the Valley Networks On Mars: A Hydrological Perspective

    NASA Technical Reports Server (NTRS)

    Gulick, Virginia C.

    2000-01-01

    The geomorphology of the Martian valley networks is examined from a hydrological perspective for their compatibility with an origin by rainfall, globally higher heat flow, and localized hydrothermal systems. Comparison of morphology and spatial distribution of valleys on geologic surfaces with terrestrial fluvial valleys suggests that most Martian valleys are probably not indicative of a rainfall origin, nor are they indicative of formation by an early global uniformly higher heat flow. In general, valleys are not uniformly distributed within geologic surface units as are terrestrial fluvial valleys. Valleys tend to form either as isolated systems or in clusters on a geologic surface unit leaving large expanses of the unit virtually untouched by erosion. With the exception of fluvial valleys on some volcanoes, most Martian valleys exhibit a sapping morphology and do not appear to have formed along with those that exhibit a runoff morphology. In contrast, terrestrial sapping valleys form from and along with runoff valleys. The isolated or clustered distribution of valleys suggests localized water sources were important in drainage development. Persistent ground-water outflow driven by localized, but vigorous hydrothermal circulation associated with magmatism, volcanism, impacts, or tectonism is, however, consistent with valley morphology and distribution. Snowfall from sublimating ice-covered lakes or seas may have provided an atmospheric water source for the formation of some valleys in regions where the surface is easily eroded and where localized geothermal/hydrothermal activity is sufficient to melt accumulated snowpacks.

  18. EPA Region 1 - Valley Depth in Meters

    EPA Pesticide Factsheets

    Raster of the Depth in meters of EPA-delimited Valleys in Region 1.Valleys (areas that are lower than their neighbors) were extracted from a Digital Elevation Model (USGS, 30m) by finding the local average elevation, subtracting the actual elevation from the average, and selecting areas where the actual elevation was below the average. The landscape was sampled at seven scales (circles of 1, 2, 4, 7, 11, 16, and 22 km radius) to take into account the diversity of valley shapes and sizes. Areas selected in at least four scales were designated as valleys.

  19. Hydrology and simulation of ground-water flow in the Tooele Valley ground-water basin, Tooele County, Utah

    USGS Publications Warehouse

    Stolp, Bernard J.; Brooks, Lynette E.

    2009-01-01

    Ground water is the sole source of drinking water within Tooele Valley. Transition from agriculture to residential land and water use necessitates additional understanding of water resources. The ground-water basin is conceptualized as a single interconnected hydrologic system consisting of the consolidated-rock mountains and adjoining unconsolidated basin-fill valleys. Within the basin fill, unconfined conditions exist along the valley margins and confined conditions exist in the central areas of the valleys. Transmissivity of the unconsolidated basin-fill aquifer ranges from 1,000 to 270,000 square feet per day. Within the consolidated rock of the mountains, ground-water flow largely is unconfined, though variability in geologic structure, stratigraphy, and lithology has created some areas where ground-water flow is confined. Hydraulic conductivity of the consolidated rock ranges from 0.003 to 100 feet per day. Ground water within the basin generally moves from the mountains toward the central and northern areas of Tooele Valley. Steep hydraulic gradients exist at Tooele Army Depot and near Erda. The estimated average annual ground-water recharge within the basin is 82,000 acre-feet per year. The primary source of recharge is precipitation in the mountains; other sources of recharge are irrigation water and streams. Recharge from precipitation was determined using the Basin Characterization Model. Estimated average annual ground-water discharge within the basin is 84,000 acre-feet per year. Discharge is to wells, springs, and drains, and by evapotranspiration. Water levels at wells within the basin indicate periods of increased recharge during 1983-84 and 1996-2000. During these periods annual precipitation at Tooele City exceeded the 1971-2000 annual average for consecutive years. The water with the lowest dissolved-solids concentrations exists in the mountain areas where most of the ground-water recharge occurs. The principal dissolved constituents are calcium

  20. Influence of elevation and forest type on community assemblage and species distribution of shrews in the central and southern Appalachian mountains

    Treesearch

    W. Mark Ford; Timothy S. McCay; Michael A. Menzel; W. David Webster; Cathryn H. Greenberg; John F. Pagels; Joseph F. Merritt; Joseph F. Merritt

    2005-01-01

    We analyzed shrew community data from 398,832 pitfall trapnights at 303 sites across the upper Piedmont, Blue Ridge, northern Ridge and Valley, southern Ridge and Valley, Cumberland Plateau and Allegheny Mountains and Plateau sections of the central and southern Appalachian Mountains from Alabama to Pennsylvania. The objectives of our research were to describe regional...

  1. Influence of elevation and forest type on community assemblage and species distribution of shrews in the central and southern Appalachian Mountains

    Treesearch

    W. Mark Ford; Timothy S. McCay; Michael A. Menzel; W. David Webster; Cathryn H. Greenberg; John F. Pagels; Joseph F. Merritt

    2006-01-01

    We analyzed shrew community data from 398,832 pitfall trapnights at 303 sites across the upper Piedmont, Blue Ridge, northern Ridge and Valley, southern Ridge and Valley, Cumberland Plateau and Allegheny Mountains and Plateau sections of the central and southern Appalachian Mountains from Alabama to Pennsylvania. The objectives of our research were to describe regional...

  2. Influence of elevation and forest type on community assemblage and species distribution of shrews in the central and southern Appalachian mountains

    Treesearch

    W. Mark Ford; Timothy S. McCay; Michael A. Menzel; W. David Webster; Cathryn H. Greenberg; John F. Pagels; Joseph F. Merritt

    2005-01-01

    We analyzed shrew community data from 398,832 pitfall trapnights at 303 sites across the upper Piedmont, Blue ridge, northern Ridge and Valley, southern Ride and Valley, Cumberland Plateau and Allegheny Mountains and Plateau sections of the central and southern Appalachian Mountains from Alabama to Pennsylvania. The objectives of our research were to describe regional...

  3. Preliminary hydrogeologic assessment near the boundary of the Antelope Valley and El Mirage Valley groundwater basins, California

    USGS Publications Warehouse

    Stamos, Christina L.; Christensen, Allen H.; Langenheim, Victoria

    2017-07-19

    The increasing demands on groundwater for water supply in desert areas in California and the western United States have resulted in the need to better understand groundwater sources, availability, and sustainability. This is true for a 650-square-mile area that encompasses the Antelope Valley, El Mirage Valley, and Upper Mojave River Valley groundwater basins, about 50 miles northeast of Los Angeles, California, in the western part of the Mojave Desert. These basins have been adjudicated to ensure that groundwater rights are allocated according to legal judgments. In an effort to assess if the boundary between the Antelope Valley and El Mirage Valley groundwater basins could be better defined, the U.S. Geological Survey began a cooperative study in 2014 with the Mojave Water Agency to better understand the hydrogeology in the area and investigate potential controls on groundwater flow and availability, including basement topography.Recharge is sporadic and primarily from small ephemeral washes and streams that originate in the San Gabriel Mountains to the south; estimates range from about 400 to 1,940 acre-feet per year. Lateral underflow from adjacent basins has been considered minor in previous studies; underflow from the Antelope Valley to the El Mirage Valley groundwater basin has been estimated to be between 100 and 1,900 acre-feet per year. Groundwater discharge is primarily from pumping, mostly by municipal supply wells. Between October 2013 and September 2014, the municipal pumpage in the Antelope Valley and El Mirage Valley groundwater basins was reported to be about 800 and 2,080 acre-feet, respectively.This study was motivated by the results from a previously completed regional gravity study, which suggested a northeast-trending subsurface basement ridge and saddle approximately 3.5 miles west of the boundary between the Antelope Valley and El Mirage Valley groundwater basins that might influence groundwater flow. To better define potential basement

  4. Control of Exciton Valley Coherence in Transition Metal Dichalcogenide Monolayers

    NASA Astrophysics Data System (ADS)

    Wang, Gang

    Current research on Transition Metal Dichalcogenide (TMD) Monolayers is stimulated by their strong light-matter interaction and the possibility to use the valley index in addition to spin as an information carrier. The direct gap interband transitions in TMD monolayers are governed by chiral optical selection rules. Determined by laser helicity, optical transitions in either the K+ or K- valley in momentum space are induced. Very recently the optical generation of valley polarization and valley coherence (coherent superposition of valley states) have been reported. In this work we go a step further by discussing the coherent manipulation of valley states. Linearly polarized laser excitation prepares a coherent superposition of valley states. We demonstrate the control of the exciton valley coherence in monolayer WSe2 by tuning the applied magnetic field perpendicular to the monolayer plane. The induced valley Zeeman splitting between K+ and K- results in a change of the oscillation frequency of the superposition of the valley states, which corresponds to a rotation of the exciton valley pseudo-spin. We show rotation of this coherent superposition of valley states by angles as large as 30 degrees in applied fields up to 9T and discuss valley coherence in other TMD monolayer materials. This exciton valley coherence control on ps time scale could be an important step towards complete control of qubits based on the valley degree of freedom. In collaboration with X. Marie, T. Amand, C. Robert, F. Cadiz, P. Renucci, B. Urbaszek (Université de Toulouse, INSA-CNRS-UPS, LPCNO, France), B. L. Liu (Institute of Physics, Chinese Academy of Sciences, China) and we acknowledge ERC Grant No. 306719.

  5. Geochemical study of travertines along middle-lower Tiber valley (central Italy): genesis, palaeo-environmental and tectonic implications

    NASA Astrophysics Data System (ADS)

    Giustini, Francesca; Brilli, Mauro; Mancini, Marco

    2018-06-01

    Several travertine deposits dating to the Pleistocene outcrop along the Tiber valley between Orte and Rome. Mineralogically, they are mainly composed of calcite; various lithofacies (stromatolitic, phytoclastic, and massive) were identified and relatively wide ranges of carbon (δ13C -8.11 to +11.42‰ vs. VPDB) and oxygen (δ18O +22.74 to +27.71‰ vs. VSMOW) isotope compositions were measured. The isotope and chemical compositions of water and free gases, in some cases associated with the travertines, were also measured. Carbon isotope data show that several samples fall in the typical range of thermogenic travertine, i.e., linked to the addition of deep inorganic CO2. The oxygen isotope composition of the springs associated with the travertine deposits points to travertine precipitation by slightly thermal water of meteoric origin. In general, these travertines are in association with, or close to, mineralised groundwaters (with slightly acidic pH, low thermalism, and enrichment in sulphates or sodium chloride) and rich CO2 gas emissions, the origin of which may be linked to decarbonation reactions. The travertine bodies are locally connected with crustal structural lineaments favouring the circulation of ascending deep CO2-rich fluids. Conversely, some samples show isotopic connotations of meteogenic deposits, representing travertines formed mainly from soil biogenic or atmospheric carbon dioxide generally present in shallow groundwater or surface water. According to their morphology and isotope data, these travertines may be attributed to the sedimentary environment of waterfalls. These new geochemical and morphological data are integrated with those already available in the literature regarding the study area and contribute to shedding light on palaeo-environmental conditions in western-central Italy during the Quaternary.

  6. Hydrology of the Sevier-Sigurd ground-water basin and other ground-water basins, central Sevier Valley, Utah.

    USGS Publications Warehouse

    Lambert, P.M.; Mason, J.L.; Puchta, R.W

    1995-01-01

    The hydrologic system in the central Sevier Valley, and more specifically the Sevier-Sigurd basin, is a complex system in which surface- and ground-water systems are interrelated. Seepage from an extensive irrigation system is the primary source of recharge to the basin-fill aquifer in the Sevier-Sigurd basin.Water-quality data indicate that inflow from streams and subsurface inflow that intersect evaporite deposits in the Arapien Shale does not adversely affect ground-water quality in the Sevier-Sigurd basin. Stable-isotope data indicate that large sulfate concentrations in water from wells are from the dissolution of gypsum within the basin fill rather than inflow from the Arapien Shale.A ground-water-flow model of the basin-fill aquifer in the Sevier-Sigurd basin was calibrated to steady-state conditions and transient conditions using yearly water-level changes from 1957-88 and monthly water-level changes from 1958-59. Predictive simulations were made to test the effects of reduced recharge from irrigation and increased well discharge. To simulate the effects of conversion from flood to sprinkler irrigation, recharge from irrigated fields was reduced by 50 percent. After twenty years, this reduction resulted in water-level declines of 1 to 8 feet in most of the basin, and a reduction in ground-water discharge to the Sevier River of 4,800 acre-ft/yr. Water-level declines of as much as 12 feet and a reduction in recharge to the Sevier River of 4,800 acre-ft/yr were the result of increasing well discharge near Richfield and Monroe by 25,000 acre-ft/yr. 

  7. Geochemical study of travertines along middle-lower Tiber valley (central Italy): genesis, palaeo-environmental and tectonic implications

    NASA Astrophysics Data System (ADS)

    Giustini, Francesca; Brilli, Mauro; Mancini, Marco

    2017-09-01

    Several travertine deposits dating to the Pleistocene outcrop along the Tiber valley between Orte and Rome. Mineralogically, they are mainly composed of calcite; various lithofacies (stromatolitic, phytoclastic, and massive) were identified and relatively wide ranges of carbon (δ13C -8.11 to +11.42‰ vs. VPDB) and oxygen (δ18O +22.74 to +27.71‰ vs. VSMOW) isotope compositions were measured. The isotope and chemical compositions of water and free gases, in some cases associated with the travertines, were also measured. Carbon isotope data show that several samples fall in the typical range of thermogenic travertine, i.e., linked to the addition of deep inorganic CO2. The oxygen isotope composition of the springs associated with the travertine deposits points to travertine precipitation by slightly thermal water of meteoric origin. In general, these travertines are in association with, or close to, mineralised groundwaters (with slightly acidic pH, low thermalism, and enrichment in sulphates or sodium chloride) and rich CO2 gas emissions, the origin of which may be linked to decarbonation reactions. The travertine bodies are locally connected with crustal structural lineaments favouring the circulation of ascending deep CO2-rich fluids. Conversely, some samples show isotopic connotations of meteogenic deposits, representing travertines formed mainly from soil biogenic or atmospheric carbon dioxide generally present in shallow groundwater or surface water. According to their morphology and isotope data, these travertines may be attributed to the sedimentary environment of waterfalls. These new geochemical and morphological data are integrated with those already available in the literature regarding the study area and contribute to shedding light on palaeo-environmental conditions in western-central Italy during the Quaternary.

  8. Acorn Yield During 1988 and 1989 on California's Central Coast

    Treesearch

    Sergio L. Garcia; Wayne A. Jensen; William H. Weitkamp; William D. Tietje

    1991-01-01

    In 1988, a study was began to evaluate acorn yield of valley oak (Quercus lobata), coast live oak (Q. agrifolia), and blue oak (Q. douglasii) in three of California's central coast counties: Santa Barbara, San Luis Obispo, and San Benito. The purpose of the study was to examine the degree and variability of...

  9. Potential for aquifer compaction, land subsidence, and earth fissures in Avra Valley, Pima and Pinal counties, Arizona

    USGS Publications Warehouse

    Anderson, S.R.

    1987-01-01

    Avra Valley is a large north-trending alluvial basin about 15 mi west of Tucson in Pima and Pinal Counties, Arizona. The climate of Avra Valley is semiarid, and the average annual precipitation ranges from 8 to 12 in. Two major ephemeral streams, the Santa Cruz River and Brawley Wash, drain the area. These streams and their tributaries provide a source of recharge to an extensive alluvial aquifer that underlies the valley floor. The aquifer consists of interbedded gravel, sand, silt, and clay and contains a vast quantity of groundwater. The physiography, fertile soil, and mild climate of Avra Valley make it an ideal environment for agriculture and urban development. Although the aquifer is replenished by natural recharge and underflow, rates of recharge and underflow have not kept pace with the rate of pumping. Pumping has exceeded recharge for several decades, resulting in a lowering of groundwater levels throughout most of the valley. In places, water level declines have resulted in small amounts of aquifer compaction and land subsidence. Earth fissures, some of which may be the result of localized differential subsidence, also have been observed in the valley. Geohydrologic characteristics of Avra Valley that may contribute to potential aquifer compaction, land subsidence, and earth fissures are described. The quantitative evaluation of potential land subsidence in this report is presented as an interim land- and water-use planning tool pending acquisition and study of additional data. Because of data limitations, the evaluation is made on the assumption that future rates of compaction and subsidence in Avra Valley will be similar to those in the Eloy-Picacho area. The evaluation also assumes that water level declines in the aquifer will continue. Several factors that may reduce groundwater withdrawals, and thus the potential for compaction and subsidence in Avra Valley, were not evaluated. These factors include the enactment of the 1980 Arizona Ground

  10. Invertebrate mercury bioaccumulation in permanent, seasonal, and flooded rice wetlands within California's Central Valley

    USGS Publications Warehouse

    Ackerman, Joshua T.; Miles, A. Keith; Eagles-Smith, Collin A.

    2010-01-01

    We examined methylmercury (MeHg) bioavailability in four of the most predominant wetland habitats in California's Central Valley agricultural region during the spring and summer: white rice, wild rice, permanent wetlands, and shallowly-flooded fallow fields. We sampled MeHg and total mercury (THg) concentrations in two aquatic macroinvertebrate taxa at the inlets, centers, and outlets of four replicated wetland habitats (8 wetlands total) during two time periods bounding the rice growing season and corresponding to flood-up and pre-harvest (96 total samples). In general, THg concentrations (mean ± standard error) in Notonectidae (Notonecta, back swimmers; 1.18 ± 0.08 µg g− 1 dry weight [dw]) were higher than in Corixidae (Corisella, water boatmen; 0.89 ± 0.06 µg g− 1 dw, MeHg: 0.74 ± 0.05 µg g− 1 dw). MeHg concentrations were correlated with THg concentrations in Corixidae (R2 = 0.80) and 88% of THg was in the MeHg form. Wetland habitat type had an important influence on THg concentrations in aquatic invertebrates, but this effect depended on the sampling time period and taxa. In particular, THg concentrations in Notonectidae, but not Corixidae, were higher in permanent wetlands than in white rice, wild rice, or shallowly-flooded fallow fields. THg concentrations in Notonectidae were higher at the end of the rice growing season than near the time of flood-up, whereas THg concentrations in Corixidae did not differ between time periods. The effect of wetland habitat type was more prevalent near the end of the rice growing season, when Notonectidae THg concentrations were highest in permanent wetlands. Additionally, invertebrate THg concentrations were higher at water outlets than at inlets of wetlands. Our results indicate that although invertebrate THg concentrations increased from the time of flood-up to draw-down of wetlands, temporarily flooded habitats such as white rice, wild rice, and shallowly-flooded fallow fields did not

  11. Use of Unmanned Aerial Vehicles for Improving Farm Scale Agricultural Water Management in Agriculture at a Farm Scale. A case study for field crops in the California's Central Valley

    NASA Astrophysics Data System (ADS)

    Medellin-Azuara, J.; Morande, J. A.; Jin, Y.; Chen, Y.; Paw U, K. T.; Viers, J. H.

    2016-12-01

    Traditional methods for estimating consumptive water use as evapotranspiration (ET) for agriculture in areas with water limitations such as California have always been a challenge for farmers, water managers, researchers and government agencies. Direct measurement of evapotranspiration (ET) and crop water stress in agriculture can be a cumbersome and costly task. Furthermore, spatial variability of applied water and irrigation and stress level in crops, due to inherent heterogeneity in soil conditions, topography, management practices, and lack of uniformity in water applications may affect estimates water use efficiency and water balances. This situation difficult long-term management of agroecosystems. This paper presents a case study for various areas in California's Central Valley using Unmanned Aerial Vehicles (UAVs) for a late portion of the 2016 irrigation season These estimates are compared those obtained by direct measurement (from previously deployed stations), and energy balance approaches with remotely sensed data in a selection of field crop parcels. This research improves information on water use and site conditions in agriculture by enhancing remote sensing-based estimations through the use of higher resolution multi-spectral and thermal imagery captured by UAV. We assess whether more frequent information at higher spatial resolution from UAVs can improve estimations of overall ET through energy balance and imagery. Stress levels and ET are characterized spatially to examine irrigation practices and their performance to improve water use in the agroecosystem. Ground based data such as air and crop temperature and stem water potential is collected to validate UAV aerial measurements. Preliminary results show the potential of UAV technology to improve timing, resolution and accuracy in the ET estimation and assessment of crop stress at a farm scales. Side to side comparison with ground level stations employing surface renewal, eddy covariance and

  12. Observation of valley-selective microwave transport in photonic crystals

    NASA Astrophysics Data System (ADS)

    Ye, Liping; Yang, Yuting; Hong Hang, Zhi; Qiu, Chunyin; Liu, Zhengyou

    2017-12-01

    Recently, the discrete valley degree of freedom has attracted extensive attention in condensed matter physics. Here, we present an experimental observation of the intriguing valley transport for microwaves in photonic crystals, including the bulk valley transport and the valley-projected edge modes along the interface separating different photonic insulating phases. For both cases, valley-selective excitations are realized by a point-like chiral source located at proper locations inside the samples. Our results are promising for exploring unprecedented routes to manipulate microwaves.

  13. 27 CFR 9.90 - Willamette Valley.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) “Roseburg,” Location Diagram NL 10-2, 1958 (revised 1970). (c) Boundaries. The Willamette Valley... valleys of Little River, Mosby Creek, Sharps Creek and Lost Creek to the intersection of R1W/R1E and State...

  14. Lay perceptions of risk factors for Rift Valley fever in a pastoral community in northeastern Kenya.

    PubMed

    Ng'ang'a, Caroline M; Bukachi, Salome A; Bett, Bernard K

    2016-01-13

    Human behavioral factors have been found to be central in the transmission of Rift Valley fever. Consumption of contaminated meat and milk in particular have been identified as one of the key risk factors for the transmission of Rift Valley fever in humans. In pastoral communities, livestock is the main source of livelihood from which many benefits such as food as well as economic and cultural services are derived. Zoonotic diseases therefore have a great impact on pastoral communities livelihoods. However, lay perceptions regarding the transmission of these diseases including Rift Valley fever hampers their effective control. This study investigated the lay perceptions of risks for Rift Valley fever transmission in a pastoral community in northeastern Kenya. A qualitative study was carried out in Ijara district, Kenya which was one of the hotspots of Rift Valley during the 2006/2007 outbreak. Data were collected using focus group discussions and narratives guided by checklists. Eight focus group discussions consisting of 83 participants and six narratives were conducted. Data was transcribed, coded and analysed according to Emergent themes. The participants reported that they had experienced Rift Valley fever in their livestock especially sheep and in humans both in 1997/1998 and 2006/2007. However, they believed that infections in humans occurred as a result of mosquito bites and had little to do with their consumption of meat, milk and blood from infected livestock. The participants in this study indicated that they had heard of the risks of acquiring the disease through consumption of livestock products but their experiences did not tally with the information they had received hence to them, Rift Valley fever was not transmissible through their dietary practices. Though the communities in this region were aware of Rift Valley fever, they did not have elaborate information regarding the disease transmission dynamics to humans. To avoid misconception about

  15. Valley photonic crystals for control of spin and topology

    NASA Astrophysics Data System (ADS)

    Dong, Jian-Wen; Chen, Xiao-Dong; Zhu, Hanyu; Wang, Yuan; Zhang, Xiang

    2017-03-01

    Photonic crystals offer unprecedented opportunity for light manipulation and applications in optical communication and sensing. Exploration of topology in photonic crystals and metamaterials with non-zero gauge field has inspired a number of intriguing optical phenomena such as one-way transport and Weyl points. Recently, a new degree of freedom, valley, has been demonstrated in two-dimensional materials. Here, we propose a concept of valley photonic crystals with electromagnetic duality symmetry but broken inversion symmetry. We observe photonic valley Hall effect originating from valley-dependent spin-split bulk bands, even in topologically trivial photonic crystals. Valley-spin locking behaviour results in selective net spin flow inside bulk valley photonic crystals. We also show the independent control of valley and topology in a single system that has been long pursued in electronic systems, resulting in topologically-protected flat edge states. Valley photonic crystals not only offer a route towards the observation of non-trivial states, but also open the way for device applications in integrated photonics and information processing using spin-dependent transportation.

  16. A review of empirical evidence on different uncanny valley hypotheses: support for perceptual mismatch as one road to the valley of eeriness

    PubMed Central

    Kätsyri, Jari; Förger, Klaus; Mäkäräinen, Meeri; Takala, Tapio

    2015-01-01

    The uncanny valley hypothesis, proposed already in the 1970s, suggests that almost but not fully humanlike artificial characters will trigger a profound sense of unease. This hypothesis has become widely acknowledged both in the popular media and scientific research. Surprisingly, empirical evidence for the hypothesis has remained inconsistent. In the present article, we reinterpret the original uncanny valley hypothesis and review empirical evidence for different theoretically motivated uncanny valley hypotheses. The uncanny valley could be understood as the naïve claim that any kind of human-likeness manipulation will lead to experienced negative affinity at close-to-realistic levels. More recent hypotheses have suggested that the uncanny valley would be caused by artificial–human categorization difficulty or by a perceptual mismatch between artificial and human features. Original formulation also suggested that movement would modulate the uncanny valley. The reviewed empirical literature failed to provide consistent support for the naïve uncanny valley hypothesis or the modulatory effects of movement. Results on the categorization difficulty hypothesis were still too scarce to allow drawing firm conclusions. In contrast, good support was found for the perceptual mismatch hypothesis. Taken together, the present review findings suggest that the uncanny valley exists only under specific conditions. More research is still needed to pinpoint the exact conditions under which the uncanny valley phenomenon manifests itself. PMID:25914661

  17. Climatology of atmospheric PM10 concentration in the Po Valley

    NASA Astrophysics Data System (ADS)

    Bigi, A.; Ghermandi, G.

    2014-01-01

    The limits to atmospheric pollutant concentration set by the European Commission provide a challenging target for the municipalities in the Po Valley, because of the characteristic climatic conditions and high population density of this region. In order to assess climatology and trends in the concentration of atmospheric particles in the Po Valley, a dataset of PM10 data from 41 sites across the Po Valley have been analysed, including both traffic and background sites (either urban, suburban or rural). Of these 41 sites, 18 with 10 yr or longer record have been analysed for long term trend in de-seasonalized monthly means, in annual quantiles and in monthly frequency distribution. A widespread significant decreasing trend has been observed at most sites, up to few percent per year, by Generalised Least Square and Theil-Sen method. All 41 sites have been tested for significant weekly periodicity by Kruskal-Wallis test for mean anomalies and by Wilcoxon test for weekend effect magnitude. A significant weekly periodicity has been observed for most PM10 series, particularly in summer and ascribed mainly to anthropic particulate emissions. A cluster analysis has been applied in order to highlight stations sharing similar pollution conditions over the reference period. Five clusters have been found, two gathering the metropolitan areas of Torino and Milano and their respective nearby sites and the other three clusters gathering north-east, north-west and central Po Valley sites respectively. Finally the observed trends in atmospheric PM10 have been compared to trends in provincial emissions of particulates and PM precursors, and analysed along with data on vehicular fleet age, composition and fuel sales. Significant basin-wide drop in emissions occurred for gaseous pollutants, contrarily to emissions of PM10 and PM2.5, whose drop resulted low and restricted to few provinces. It is not clear whether the decrease for only gaseous emissions is sufficient to explain the

  18. Surnames and genetic structure of a high-altitude Quechua community from the Ichu River Valley, Peruvian Central Andes, 1825-1914.

    PubMed

    Pettener, D; Pastor, S; Tarazona-Santos, E

    1998-10-01

    Changes in isolation, inbreeding, population subdivision, and isonymous relationships are examined in six Quechua communities from the upper valley of the Ichu River in the Peruvian Central Andes (3700 m). All marriages registered between 1825 and 1914 in the Parish of Santa Ana were analyzed. The data (1680 marriages) were divided into 2 periods (1825-1870 and 1871-1914) and into the 6 villages that constitute the parish. Endogamy rates are between 81% and 100%, indicating high levels of reproductive isolation. The inbreeding indicated by isonymy (Ft, Fr, and Fn) is lower than in other mountain populations studied. Isonymy values, calculated from the different surname combinations made possible by the Ibero-American Surnames System, indicate a strong rejection of consanguineous marriages, particularly between patrilineal relatives, in agreement with the parental structure typical of Andean populations. The comparison between observed and expected repeated-pair values reveals a moderate level of subdivision within populations, which could be related to cultural and socioeconomic factors. Nonmetric multidimensional scaling was used to investigate temporal changes in the isonymous relationships among the communities. The results reveal a decrease in the interpopulational variability measured by surnames, in agreement with an increase in exogamy. Surnames and data contained in historical and demographic records yield reliable information, and they can be used to reconstruct the biological history of Amerindian populations over the last few centuries.

  19. An 11 000-year-long record of fire and vegetation history at Beaver Lake, Oregon, central Willamette Valley

    Treesearch

    Megan K. Walsh; Christopher A. Pearl; Cathy Whitlock; Patrick J. Bartlein; Marc A. Worona

    2010-01-01

    High-resolution macroscopic charcoal and pollen analysis were used to reconstruct an 11 000-year-long record of fire and vegetation history from Beaver Lake, Oregon, the first complete Holocene paleoecological record from the floor of the Willamette Valley. In the early Holocene (ca 11 000-7500 calendar years before present [cal yr BP]), warmer, drier summers than at...

  20. Geohydrology of the central Mesilla Valley, Dona Ana County, New Mexico

    USGS Publications Warehouse

    Wilson, Clyde A.; White, Robert R.

    1984-01-01

    Five large-capacity irrigation wells, with depths ranging from 370 to 686 feet, were drilled by the Elephant Butte Irrigation District between 1973 and 1975, in the Mesilla Valley about 7 miles south of Las Cruces, New Mexico. These were the first deep wells in the area, and their installation provided an opportunity to conduct extensive aquifer tests under relatively undisturbed conditions. The deep irrigation wells are perforated in the Santa Fe Group of Miocene to Pleistocene Age. The Santa Fe Group is composed of interfingering and alternating beds of clay, silt, sand, and small gravel. In the area of these wells, the upper part of the saturated zone contains slightly saline water to a depth of about 100 to 175 feet below the water table, underlain by a freshwater zone extending to depths greater than 1,200 feet. As water is pumped from the freshwater zone, leakage occurs from above and below the perforated interval. At one of the irrigation district wells, slightly saline water moved downward because of a lack of confining layers in the aquifer. At three other wells, the surface casing was not set deep enough and slightly saline water moved into the top of the perforations , downward in the casing, and into the freshwater part of the aquifer. (USGS)

  1. Controls on Mississippi Valley-Type Zn-Pb mineralization in Behabad district, Central Iran: Constraints from spatial and numerical analyses

    NASA Astrophysics Data System (ADS)

    Parsa, Mohammad; Maghsoudi, Abbas

    2018-04-01

    The Behabad district, located in the central Iranian microcontinent, contains numerous epigenetic stratabound carbonate-hosted Zn-Pb ore bodies. The mineralizations formed as fault, fracture and karst fillings in the Permian-Triassic formations, especially in Middle Triassic dolostones, and comprise mainly non-sulfides zinc ores. These are all interpreted as Mississippi Valley-type (MVT) base metal deposits. From an economic geological point of view, it is imperative to recognize the processes that have plausibly controlled the emplacement of MVT Zn-Pb mineralization in the Behabad district. To address the foregoing issue, analyses of the spatial distribution of mineral deposits comprising fry and fractal techniques and analysis of the spatial association of mineral deposits with geological features using distance distribution analysis were applied to assess the regional-scale processes that could have operated in the distribution of MVT Zn-Pb deposits in the district. The obtained results based on these analytical techniques show the main trends of the occurrences are NW-SE and NE-SW, which are parallel or subparallel to the major northwest and northeast trending faults, supporting the idea that these particular faults could have acted as the main conduits for transport of mineral-bearing fluids. The results of these analyses also suggest that Permian-Triassic brittle carbonate sedimentary rocks have served as the lithological controls on MVT mineralization in the Behabad district as they are spatially and temporally associated with mineralization.

  2. Low clouds in central California

    NASA Image and Video Library

    2015-02-10

    Low clouds filled California’s Central Valley in late January, 2015. Such winter fog is considered a common phenomenon, and can be so dense that it snarls traffic, causes fender-benders, and can make symptoms worse in those with respiratory disease. At the same time, the moist winter fog helps keep temperatures low in the rich agricultural region by reflecting sunlight and keeping the ground from warming, which helps keep the abundant fruit and nut trees dormant, allowing for bountiful harvests. Scientific studies have reported that winter fogs (also called Thule fogs) are occurring less frequently in the Central Valley. One study, by Dennis Baldocchi and Eric Waller, was published in May, 2014. It finds that since 1981 the number of fog days between November and February has decreased by 46 percent. The severe drought that California has experienced in recent years may also have decreased the number of fog events even more since 2012. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite captured this true-color image on January 24, 2015. Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  3. 2. CLOSEUP OF THE ORNAMENTAL LIGHTS, THE CENTRAL BIFOLD DOORS, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. CLOSEUP OF THE ORNAMENTAL LIGHTS, THE CENTRAL BIFOLD DOORS, AND THE EXAGGERATED TRIGLYTHS ABOVE THE DOOR, LOOKING WEST. NOTE THE PERSONNEL DOOR COMPRISED OF THE BOTTOM THREE PANELS IN THE LEFT BIFOLD DOOR. - Wyoming Valley Flood Control System, Woodward Pumping Station, East of Toby Creek crossing by Erie-Lackawanna Railroad, Edwardsville, Luzerne County, PA

  4. Comparison of Oxygenate Mixing Ratios Observed in the San Joaquin Valley, California, as a Consequence of Dairy Farming

    NASA Astrophysics Data System (ADS)

    Yang, M. M.; Blake, D. R.

    2009-12-01

    The San Joaquin Valley Air Basin in Central California is plagued with air quality problems, and is classified by the U.S. Environmental Protection Agency (EPA) as a serious non-attainment area for health-based eight-hour federal ozone (smog) standard (1). One of the main sources of Volatile Organic Compounds (VOCs), and indirect sources of ozone in the Valley, has been identified as dairy farming (2). Among these compounds, we have found that several OVOCs such as ethanol, methanol, acetone and acetaldehyde are produced in major quantities throughout the San Joaquin valley as by-products of yeast fermentation of silage and photochemical oxidation. These oxygenates, especially ethanol, play an important role in ozone (O3) formation within the valley. Since 2008, several different types of sampling protocols have been employed by our group in order to determine the degree of enhancement of the four oxygenates in the valley air shed, as well as to determine their sources, emission profiles and emission rates (2). In 2008 and 2009, samples were in early summer, allowing us to compare the difference in concentration levels between both years.The photochemical production of ozone was calculated for each of the four oxygenates and approximately one hundred other quantified VOCs. Based on the Maximum Incremental Reactivity (MIR) scale and concentrations of each oxygenate in the atmosphere, for both 2008 and 2009, as much as 15% of O3 production in the valley is from ethanol and its photochemical by-product acetaldehyde. Our findings suggest that the data observed in 2008 is consistent with that observed in 2009, with a slight decrease in concentrations overall for 2009. 1. Lindberg, J. Analysis of the San Joaquin Valley 2007 Ozone Plan. State of California Air Resources Board. Final Draft Staff Report. 5/30/2007. 2. M. Yang, S. Meinardi, C. Krauter, D.R. Blake. Characterization of VOC Emissions from Various Components of Dairy Farming and their effect on San Joaquin

  5. Napa Valley Community College District and Napa Valley College Faculty Association/CTA/NEA 1988-89 Agreement.

    ERIC Educational Resources Information Center

    Napa Valley Community Coll. District, Napa, CA.

    The collective bargaining agreement between the Board of Trustees of the Napa Valley Community College District and the Napa Valley College Faculty Association/California Teachers Association/National Education Association is presented. This contract, in effect from June 1988 through July 1989, deals with the following topics: bargaining agent…

  6. Reexaming Owens Valley: Partitioning of Discrete and Distributed Transtension, Structural Controls on Magmatism, and Seismic Potential within an Active Rift Zone, Eastern California.

    NASA Astrophysics Data System (ADS)

    Levy, D. A.; Haproff, P. J.; Yin, A.

    2016-12-01

    Crustal-scale transtensional deformation is common in intracontinental extensional settings. However, along-strike variations in the geometry, kinematics, and linkages between rift-related faults, along with controls on local magmatic plumbing, remain inadequately examined. In this study, we conducted geologic mapping of active structures within central and northern Owens Valley of eastern California. C. Owens Valley features right-slip oblique deformation accommodated by three discrete north-south-trending faults: (1) the right-slip Owens Valley fault (OVF) and rift-bounding (2) Sierra Nevada Frontal fault (SNFF) and (3) the White-Inyo Mountains fault (WIMF). The OVF also serves as a lithospheric-scale, vertical conduit for asthenospheric-derived magma to migrate upwards and erupt at Big Pine Volcanic Field. Right-slip shear within C. Owens Valley is transferred to the SNFF of N. Owens Valley via the Poverty Hills restraining bend. In contrast to C. Owens Valley, the northern segment is dominated by distributed E-W to NE-SW-oriented extension, evidenced by normal fault scarps throughout Volcanic Tablelands and basin floor. Furthermore, the White Mountain fault which bounds N. Owens Valley to the east consists of a master west-dipping detachment fault that thinned the lithosphere, allowing for asthenospheric upwelling into the crust beneath the western rift shoulder. Subvertical, right-slip faults of the SNFF provide a conduit for magma to erupt on the surface throughout the Long Valley Caldera, Mono-Inyo Craters, and Mono Basin region. Our mapping demonstrates complex strain partitioning of discrete and distributed deformation within an alternating pure and simple shear, transtensional rift zone. Lastly, we present previously unknown relationships in Owens Valley between lithospheric-scale fault systems, seismic potential, and rift magmatism.

  7. Channels and valleys on Mars

    NASA Technical Reports Server (NTRS)

    Baker, V. R.

    1983-01-01

    Tentative conclusions about the origins of channels and valleys on Mars based on the consensus of investigators who have studied the problem are presented. The morphology of outflow channels is described in detail, and the morphology, distribution, and genesis of Martian valleys are addressed. Secondary modification of channels and valleys by mass-wasting phenomena, eolian processes, cratering, and mantling by lava flows is discussed. The physics of the flows needed to account for the immense volumes of Martian outflow channels is considered in detail, including the possible influence of debris flows and mudflows, glaciers, and ice sheets. It is concluded that Mars once probably possessed an atmosphere with higher temperatures and pressures than at present which played an essential role in an active hydrological cycle.

  8. The geochemistry of groundwater resources in the Jordan Valley: The impact of the Rift Valley brines

    USGS Publications Warehouse

    Farber, E.; Vengosh, A.; Gavrieli, I.; Marie, Amarisa; Bullen, T.D.; Mayer, B.; Polak, A.; Shavit, U.

    2007-01-01

    The chemical composition of groundwater in the Jordan Valley, along the section between the Sea of Galilee and the Dead Sea, is investigated in order to evaluate the origin of the groundwater resources and, in particular, to elucidate the role of deep brines on the chemical composition of the regional groundwater resources in the Jordan Valley. Samples were collected from shallow groundwater in research boreholes on two sites in the northern and southern parts of the Jordan Valley, adjacent to the Jordan River. Data is also compiled from previous published studies. Geochemical data (e.g., Br/Cl, Na/Cl and SO4/Cl ratios) and B, O, Sr and S isotopic compositions are used to define groundwater groups, to map their distribution in the Jordan valley, and to evaluate their origin. The combined geochemical tools enabled the delineation of three major sources of solutes that differentially affect the quality of groundwater in the Jordan Valley: (1) flow and mixing with hypersaline brines with high Br/Cl (>2 ?? 10-3) and low Na/Cl (<0.8) ratios; (2) dissolution of highly soluble salts (e.g., halite, gypsum) in the host sediments resulting in typically lower Br/Cl signal (<2 ?? 10-3); and (3) recharge of anthropogenic effluents, primarily derived from evaporated agricultural return flow that has interacted (e.g., base-exchange reactions) with the overlying soil. It is shown that shallow saline groundwaters influenced by brine mixing exhibit a north-south variation in their Br/Cl and Na/Cl ratios. This chemical trend was observed also in hypersaline brines in the Jordan valley, which suggests a local mixing process between the water bodies. ?? 2007 Elsevier Ltd. All rights reserved.

  9. 36 CFR 7.26 - Death Valley National Monument.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Death Valley National... INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.26 Death Valley National Monument. (a) Mining. Mining in Death Valley National Monument is subject to the following regulations, which are...

  10. Total carbon and nitrogen in mineral soil after 26 years of prescribed fire: Long Valley and Fort Valley Experimental Forests

    Treesearch

    Daniel G. Neary; Sally M. Haase; Steven T. Overby

    2008-01-01

    Prescribed fire was introduced to high density ponderosa pine stands at Fort Valley and Long Valley Experimental Forests in 1976. This paper reports on mineral soil total carbon (C) and nitrogen (N) at Long Valley. Total soil C and N levels were highly variable and exhibited an increasing, but inconsistent, concentration trend related to burn interval. Total N ranged...

  11. Valley-polarized quantum transport generated by gauge fields in graphene

    NASA Astrophysics Data System (ADS)

    Settnes, Mikkel; Garcia, Jose H.; Roche, Stephan

    2017-09-01

    We report on the possibility to simultaneously generate in graphene a bulk valley-polarized dissipative transport and a quantum valley Hall effect by combining strain-induced gauge fields and real magnetic fields. Such unique phenomenon results from a ‘resonance/anti-resonance’ effect driven by the superposition/cancellation of superimposed gauge fields which differently affect time reversal symmetry. The onset of a valley-polarized Hall current concomitant to a dissipative valley-polarized current flow in the opposite valley is revealed by a {{e}2}/h Hall conductivity plateau. We employ efficient linear scaling Kubo transport methods combined with a valley projection scheme to access valley-dependent conductivities and show that the results are robust against disorder.

  12. Subsurface geology of a potential waste emplacement site, Salt Valley Anticline, Grand County, Utah

    USGS Publications Warehouse

    Hite, R.J.

    1977-01-01

    The Salt Valley anticline, which is located about 32 km northeast of Moab, Utah, is perhaps one of the most favorable waste emplacement sites in the Paradox basin. The site, which includes about 7.8 km 2, is highly accessible and is adjacent to a railroad. The anticline is one of a series of northwest-trending salt anticlines lying along the northeast edge of the Paradox basin. These anticlines are cored by evaporites of the Paradox Member of the Hermosa Formation of Middle Pennsylvanian age. The central core of the Salt Valley anticline forms a ridgelike mass of evaporites that has an estimated amplitude of 3,600 m. The evaporite core consists of about 87 percent halite rock, which includes some potash deposits; the remainder is black shale, silty dolomite, and anhydrite. The latter three lithologies are referred to as 'marker beds.' Using geophysical logs from drill holes on the anticline, it is possible to demonstrate that the marker beds are complexly folded and faulted. Available data concerning the geothermal gradient and heatflow at the site indicate that heat from emplaced wastes should be rapidly dissipated. Potentially exploitable resources of potash and petroleum are present at Salt Valley. Development of these resources may conflict with use of the site for waste emplacement.

  13. Structural organization of process zones in upland watersheds of central Nevada and its influence on basin connectivity, dynamics, and wet meadow complexes

    Treesearch

    Jerry R. Miller; Mark L. Lord; Lionel F. Villarroel; Dru Germanoski; Jeanne C. Chambers

    2012-01-01

    The drainage network within upland watersheds in central Nevada can be subdivided into distinct zones each dominated by a unique set of processes on the basis of valley form, the geological materials that comprise the valley floor, and the presence or absence of surficial channels. On hillslopes, the type and structure (frequency, length, and spatial arrangement) of...

  14. Valley-selective optical Stark effect in monolayer WS2

    NASA Astrophysics Data System (ADS)

    Gedik, Nuh

    Monolayer semiconducting transition-metal dichalcogenides (TMDs) have a pair of valleys that, by time-reversal symmetry, are energetically degenerate. Lifting the valley degeneracy in these materials is of great interest because it would allow for valley specific band engineering and offer additional control in valleytronic applications. In this talk, I will show that circularly polarized light, which breaks time-reversal symmetry, can be used to lift the valley degeneracy by means of the optical Stark effect. We demonstrate that this effect is capable of raising the exciton level in monolayer TMD WS2 by as much as 18 meV in a controllable valley-selective manner. The resulting energy shift is extremely large, comparable to the shift that would be obtained using a very high magnetic field (approximately 100 Tesla). These results offer a novel way to control valley degree of freedom, and may provide a means to realize new valley-selective Floquet topological state of matter.

  15. Hypogene caves of the central Appalachian Shenandoah Valley in Virginia

    USGS Publications Warehouse

    Doctor, Daniel H.; Orndorff, Wil

    2017-01-01

    Several caves in the Shenandoah Valley in Virginia show evidence for early hypogenic conduit development with later-enhanced solution under partly confined phreatic conditions guided by geologic structures. Many (but not all) of these caves have been subsequently invaded by surface waters as a result of erosion and exhumation. Those not so affected are relict phreatic caves, bearing no relation to modern drainage patterns. Field and petrographic evidence shows that carbonate rocks hosting certain relict phreatic caves were dolomitized and/or silicified by early hydrothermal fluid migration in zones that served to locally enhance rock porosity, thus providing preferential pathways for later solution by groundwater flow, and making the surrounding bedrock more resistant to surficial weathering to result in caves that reside within isolated hills on the land surface. Features suggesting that deep phreatic processes dominated the development of these relict caves include (1) cave passage morphologies indicative of ascending fluids, (2) cave plans of irregular pattern, reflecting early maze or anastomosing development, (3) a general lack of cave breakdown and cave streams or cave stream deposits, and (4) calcite wall and pool coatings within isolated caves intersecting the local water table, and within unroofed caves at topographic locations elevated well above the local base level. Episodes of deep karstification were likely separated by long periods of geologic time, encompassing multiple phases of sedimentary fill and excavation within caves, and reflect a complex history of deep fluid migration that set the stage for later shallow speleogenesis that continues today.

  16. Groundwater sapping valleys: Experimental studies, geological controls and implications to the interpretation of valley networks on Mars

    NASA Technical Reports Server (NTRS)

    Kochel, R. Craig

    1988-01-01

    An integrated approach using experimental laboratory models, field studies of terrestrial analogs, and remote studies of terrestrial field sites were applied to the goals of understanding the nature and morphology of valley networks formed by groundwater sapping. In spite of problems with scaling, the experimental studies provide valuable insights into concepts relating to the initiation, development, and evolution of valleys by groundwater sapping. These investigations are also aimed at developing geomorphic criteria for distinguishing valleys formed by surface runoff from those formed by groundwater sapping processes. Channels that were field classified as sapping vs. runoff were successfully distinguished using statistical analysis of their respective morphologies; therefore, it may be possible to use similar techniques to interpret channel genesis on Mars. The terrestrial and flume studies provide the ground truth dataset which can be used (and will be during the present year) to help interpret the genesis of valley networks on Mars.

  17. SRTM Perspective View with Landsat Overlay: San Joaquin Valley, California

    NASA Technical Reports Server (NTRS)

    2000-01-01

    San Joaquin, the name given to the southern portion of California's vast Central Valley, has been called the world's richest agricultural valley. In this perspective view generated using data from the Shuttle Radar Topography Mission and an enhanced Landsat image, we are looking toward the southwest over a checkerboard pattern of agricultural fields. Mt. Pinos, a popular location for stargazing at 2,692 meters (8,831 feet) looms above the valley floor and is visible on the left side of the image. The productive southern San Joaquin is in reality a desert, averaging less than 12.7 cm (5 inches) of rain per year. Through canals and irrigation, the region nurtures some two hundred crops including grapes, figs, apricots, oranges, and more than 4,047 square-km (1,000,000 acres) of cotton. The California Aqueduct, transporting water from the Sacramento River Delta through the San Joaquin, runs along the base of the low-lying Wheeler Ridge on the left side of the image. The valley is not all agriculture though. Kern County, near the valley's southern end, is the United States' number one oil producing county, and actually produces more crude oil than Oklahoma. For visualization purposes, topographic heights displayed in this image are exaggerated two times. Colors, from Landsat data, approximate natural color.

    The elevation data used in this image was acquired by SRTM aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of Earth's land surface. To collect the 3-D SRTM data, engineers added a mast 60 meters (about 200 feet)long, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the NASA, the National Imagery and Mapping Agency (NIMA) of the U

  18. Groundwater quality in the Santa Clara River Valley, California

    USGS Publications Warehouse

    Burton, Carmen A.; Landon, Matthew K.; Belitz, Kenneth

    2011-01-01

    The Santa Clara River Valley (SCRV) study unit is located in Los Angeles and Ventura Counties, California, and is bounded by the Santa Monica, San Gabriel, Topatopa, and Santa Ynez Mountains, and the Pacific Ocean. The 460-square-mile study unit includes eight groundwater basins: Ojai Valley, Upper Ojai Valley, Ventura River Valley, Santa Clara River Valley, Pleasant Valley, Arroyo Santa Rosa Valley, Las Posas Valley, and Simi Valley (California Department of Water Resources, 2003; Montrella and Belitz, 2009). The SCRV study unit has hot, dry summers and cool, moist winters. Average annual rainfall ranges from 12 to 28 inches. The study unit is drained by the Ventura and Santa Clara Rivers, and Calleguas Creek. The primary aquifer system in the Ventura River Valley, Ojai Valley, Upper Ojai Valley, and Simi Valley basins is largely unconfined alluvium. The primary aquifer system in the remaining groundwater basins mainly consists of unconfined sands and gravels in the upper portion and partially confined marine and nonmarine deposits in the lower portion. The primary aquifer system in the SCRV study unit is defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health (CDPH) database. Public-supply wells typically are completed in the primary aquifer system to depths of 200 to 1,100 feet below land surface (bls). The wells contain solid casing reaching from the land surface to a depth of about 60-700 feet, and are perforated below the solid casing to allow water into the well. Water quality in the primary aquifer system may differ from the water in the shallower and deeper parts of the aquifer. Land use in the study unit is approximately 40 percent (%) natural (primarily shrubs, grassland, and wetlands), 37% agricultural, and 23% urban. The primary crops are citrus, avocados, alfalfa, pasture, strawberries, and dry beans. The largest urban areas in the study unit are the cities of

  19. Inferences on the hydrothermal system beneath the resurgent dome in Long Valley Caldera, east-central California, USA, from recent pumping tests and geochemical sampling

    USGS Publications Warehouse

    Farrar, C.D.; Sorey, M.L.; Roeloffs, E.; Galloway, D.L.; Howle, J.F.; Jacobson, R.

    2003-01-01

    Quaternary volcanic unrest has provided heat for episodic hydrothermal circulation in the Long Valley caldera, including the present-day hydrothermal system, which has been active over the past 40 kyr. The most recent period of crustal unrest in this region of east-central California began around 1980 and has included periods of intense seismicity and ground deformation. Uplift totaling more than 0.7 m has been centered on the caldera's resurgent dome, and is best modeled by a near-vertical ellipsoidal source centered at depths of 6-7 km. Modeling of both deformation and microgravity data now suggests that (1) there are two inflation sources beneath the caldera, a shallower source 7-10 km beneath the resurgent dome and a deeper source ???15 km beneath the caldera's south moat and (2) the shallower source may contain components of magmatic brine and gas. The Long Valley Exploration Well (LVEW), completed in 1998 on the resurgent dome, penetrates to a depth of 3 km directly above this shallower source, but bottoms in a zone of 100??C fluid with zero vertical thermal gradient. Although these results preclude extrapolations of temperatures at depths below 3 km, other information obtained from flow tests and fluid sampling at this well indicates the presence of magmatic volatiles and fault-related permeability within the metamorphic basement rocks underlying the volcanic fill. In this paper, we present recently acquired data from LVEW and compare them with information from other drill holes and thermal springs in Long Valley to delineate the likely flow paths and fluid system properties under the resurgent dome. Additional information from mineralogical assemblages in core obtained from fracture zones in LVEW documents a previous period of more vigorous and energetic fluid circulation beneath the resurgent dome. Although this system apparently died off as a result of mineral deposition and cooling (and/or deepening) of magmatic heat sources, flow testing and tidal

  20. Precipitation and runoff simulations of select perennial and ephemeral watersheds in the middle Carson River basin, Eagle, Dayton, and Churchill Valleys, west-central Nevada

    USGS Publications Warehouse

    Jeton, Anne E.; Maurer, Douglas K.

    2011-01-01

    The effect that land use may have on streamflow in the Carson River, and ultimately its impact on downstream users can be evaluated by simulating precipitation-runoff processes and estimating groundwater inflow in the middle Carson River in west-central Nevada. To address these concerns, the U.S. Geological Survey, in cooperation with the Bureau of Reclamation, began a study in 2008 to evaluate groundwater flow in the Carson River basin extending from Eagle Valley to Churchill Valley, called the middle Carson River basin in this report. This report documents the development and calibration of 12 watershed models and presents model results and the estimated mean annual water budgets for the modeled watersheds. This part of the larger middle Carson River study will provide estimates of runoff tributary to the Carson River and the potential for groundwater inflow (defined here as that component of recharge derived from percolation of excess water from the soil zone to the groundwater reservoir). The model used for the study was the U.S. Geological Survey's Precipitation-Runoff Modeling System, a physically based, distributed-parameter model designed to simulate precipitation and snowmelt runoff as well as snowpack accumulation and snowmelt processes. Models were developed for 2 perennial watersheds in Eagle Valley having gaged daily mean runoff, Ash Canyon Creek and Clear Creek, and for 10 ephemeral watersheds in the Dayton Valley and Churchill Valley hydrologic areas. Model calibration was constrained by daily mean runoff for the 2 perennial watersheds and for the 10 ephemeral watersheds by limited indirect runoff estimates and by mean annual runoff estimates derived from empirical methods. The models were further constrained by limited climate data adjusted for altitude differences using annual precipitation volumes estimated in a previous study. The calibration periods were water years 1980-2007 for Ash Canyon Creek, and water years 1991-2007 for Clear Creek. To

  1. The Pahrump Valley Museum Yucca Mountain History Exhibit - 12389

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Voegele, Michael; McCracken, Robert; Herrera, Troy

    As part of its management of the Yucca Mountain project, the Department of Energy maintained several information centers to provide public access to information about the status of the Yucca Mountain project. Those information centers contained numerous displays, historical information, and served as the location for the Department's outreach activities. As the Department of Energy dealt with reduced budgets in 2009 following the Obama Administration's intent to terminate the program, it shut down its information centers. Nye County considered it important to maintain a public information center where people would be able to find information about what was happening withmore » the Yucca Mountain project. Initially the Nye County assumed responsibility for the information center in Pahrump; eventually the County made a decision to move that information center into an expansion of the existing Pahrump Valley Museum. Nye County undertook an effort to update the information about the Yucca Mountain project and modernize the displays. A parallel effort to create a source of historical information where people could find out about the Yucca Mountain project was undertaken. To accompany the Yucca Mountain exhibits in the Pahrump Valley Museum, Nye County also sponsored a series of interviews to document, through oral histories, as much information about the Yucca Mountain project as could be found in these interviews. The paper presents an overview of the Yucca Mountain exhibits in the Pahrump Valley Museum, and the accompanying oral histories. An important conclusion that can be drawn from the interviews is that construction of a repository in Nevada should have been conceptualized as but the first step in transforming the economy of central Nevada by turning part of the Nevada National Security Site and adjoining area into a world-class energy production and energy research center. (authors)« less

  2. Digital Data from the Great Sand Dunes and Poncha Springs Aeromagnetic Surveys, South-Central Colorado

    USGS Publications Warehouse

    Drenth, B.J.; Grauch, V.J.S.; Bankey, Viki; New Sense Geophysics, Ltd.

    2009-01-01

    This report contains digital data, image files, and text files describing data formats and survey procedures for two high-resolution aeromagnetic surveys in south-central Colorado: one in the eastern San Luis Valley, Alamosa and Saguache Counties, and the other in the southern Upper Arkansas Valley, Chaffee County. In the San Luis Valley, the Great Sand Dunes survey covers a large part of Great Sand Dunes National Park and Preserve and extends south along the mountain front to the foot of Mount Blanca. In the Upper Arkansas Valley, the Poncha Springs survey covers the town of Poncha Springs and vicinity. The digital files include grids, images, and flight-line data. Several derivative products from these data are also presented as grids and images, including two grids of reduced-to-pole aeromagnetic data and data continued to a reference surface. Images are presented in various formats and are intended to be used as input to geographic information systems, standard graphics software, or map plotting packages.

  3. Geology of the Greenwater Range, and the dawn of Death Valley, California—Field guide for the Death Valley Natural History Conference, 2013

    USGS Publications Warehouse

    Calzia, J.P.; Rämö, O.T.; Jachens, Robert; Smith, Eugene; Knott, Jeffrey

    2016-05-02

    Much has been written about the age and formation of Death Valley, but that is one—if not the last—chapter in the fascinating geologic history of this area. Igneous and sedimentary rocks in the Greenwater Range, one mountain range east of Death Valley, tell an earlier story that overlaps with the formation of Death Valley proper. This early story has been told by scientists who have studied these rocks for many years and continue to do so. This field guide was prepared for the first Death Valley Natural History Conference and provides an overview of the geology of the Greenwater Range and the early history (10–0 Ma) of Death Valley.

  4. Hydraulic and mechanical properties affecting ground-water flow and aquifer-system compaction, San Joaquin Valley, California

    USGS Publications Warehouse

    Sneed, Michelle

    2001-01-01

    This report summarizes hydraulic and mechanical properties affecting ground-water flow and aquifer-system compaction in the San Joaquin Valley, a broad alluviated intermontane structural trough that constitutes the southern two-thirds of the Central Valley of California. These values will be used to constrain a coupled ground-water flow and aquifer-system compaction model of the western San Joaquin Valley called WESTSIM. A main objective of the WESTSIM model is to evaluate potential future land subsidence that might occur under conditions in which deliveries of imported surface water for agricultural use are reduced and ground-water pumping is increased. Storage values generally are components of the total aquifer-system storage and include inelastic and elastic skeletal storage values of the aquifers and the aquitards that primarily govern the potential amount of land subsidence. Vertical hydraulic conductivity values generally are for discrete thicknesses of sediments, usually aquitards, that primarily govern the rate of land subsidence. The data were compiled from published sources and include results of aquifer tests, stress-strain analyses of borehole extensometer observations, laboratory consolidation tests, and calibrated models of aquifer-system compaction.

  5. 27 CFR 9.191 - Ramona Valley.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Ramona Valley. 9.191 Section 9.191 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT...) Borrego Valley, California, 1982 edition; and (2) El Cajon, California, 1979 edition. (c) Boundary. The...

  6. 27 CFR 9.191 - Ramona Valley.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Ramona Valley. 9.191 Section 9.191 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT...) Borrego Valley, California, 1982 edition; and (2) El Cajon, California, 1979 edition. (c) Boundary. The...

  7. A Quantitative Analysis of the Fretted Terrain Valleys, Arabia Terra, Mars

    NASA Astrophysics Data System (ADS)

    Mason, Kelsey Anne

    Fretted terrain describes regions on Mars with low-lying, flat valleys separated by steep cliffs that often form polygonal-shaped mesas. The fretted terrain valleys have a morphology distinct from other valleys found on Mars, and their unknown origin may hold insights into critical questions about Mars' tectonic, magmatic, and hydrologic history. Current hypothesis for the formation of the fretted terrain include fracturing as well as hydrological flow processes such as fluvial or glacial erosion. The region for this study is located in eastern Arabia Terra and is the type-location for fretted terrain. By qualitatively and quantitatively documenting the planform, or map-view, valley geometries and orientations throughout the fretted terrain, this study better constrains the origin of the valleys. Valleys were mapped using automated routines in ArcGIS including the D8 flow direction algorithm. Valleys were then grouped geographically into basins and also by Strahler order. The valleys were then segmented every 50 km and the azimuth of each segment was calculated. The resulting valley azimuths were analyzed using rose diagrams to quantitatively describe the planform geometries of the valleys. Qualitatively, the majority of basins were found to have rectangular valley geometries. The downslope direction was calculated for each basin, and it was compared to the corresponding valley azimuths. The basins with rectangular valley geometries had valleys with an azimuth mode nearly parallel to the downslope direction and another azimuth mode perpendicular to the downslope direction. The valley azimuth mode parallel to the downslope direction is attributed to hydrological flow processes while the mode perpendicular to the downslope direction is attributed to fracturing related to the formation or existence of the Mars global dichotomy boundary.

  8. Modelling the Crust beneath the Kashmir valley in Northwestern Himalaya

    NASA Astrophysics Data System (ADS)

    Mir, R. R.; Parvez, I. A.; Gaur, V. K.; A.; Chandra, R.; Romshoo, S. A.

    2015-12-01

    We investigate the crustal structure beneath five broadband seismic stations in the NW-SE trendingoval shaped Kashmir valley sandwiched between the Zanskar and the Pir Panjal ranges of thenorthwestern Himalaya. Three of these sites were located along the southwestern edge of the valley andthe other two adjoined the southeastern. Receiver Functions (RFs) at these sites were calculated usingthe iterative time domain deconvolution method and jointly inverted with surface wave dispersiondata to estimate the shear wave velocity structure beneath each station. To further test the results ofinversion, we applied forward modelling by dividing the crust beneath each station into 4-6homogeneous, isotropic layers. Moho depths were separately calculated at different piercing pointsfrom the inversion of only a few stacked receiver functions of high quality around each piercing point.These uncertainties were further reduced to ±2 km by trial forward modelling as Moho depths werevaried over a range of ±6 km in steps of 2 km and the synthetic receiver functions matched with theinverted ones. The final values were also found to be close to those independently estimated using theH-K stacks. The Moho depths on the eastern edge of the valley and at piercing points in itssouthwestern half are close to 55 km, but increase to about 58 km on the eastern edge, suggesting thathere, as in the central and Nepal Himalaya, the Indian plate dips northeastwards beneath the Himalaya.We also calculated the Vp/Vs ratio beneath these 5 stations which were found to lie between 1.7 and1.76, yielding a Poisson's ratio of ~0.25 which is characteristic of a felsic composition.

  9. Dynamics of valley pseudospin in single-layer WSe2. Inter-valley scattering mediated by electron-phonon interaction

    NASA Astrophysics Data System (ADS)

    Molina-Sanchez, Alejandro; Sangalli, Davide; Wirtz, Ludger; Marini, Andrea

    In a time-dependent Kerr experiment a circularly polarized laser field is used to selectively populate the K+/- electronic valleys of single-layer WSe2. This carrier population corresponds to a finite pseudospin polarization that dictates the valleytronic properties of WSe2, but whose decay mechanism still remains largely debated. Time-dependent Kerr experiments provide an accurate way to visualize the pseudospin dynamics by measuring the rotation of a linearly polarized probe pulse applied after a circularly polarized and short pump pulse. We present here a clear, accurate and parameter-free description of the valley pseudospin dynamics in single-layer WSe2. By using an ab-initio approach we solve unambiguously the long standing debate about the dominant mechanism that drives the valley depolarization. Our results are in excellent agreement with recent time-dependent Kerr experiments. The decay dynamics and peculiar temperature dependence is explained in terms of electron phonon mediated processes that induce spin-flip inter-valley transitions.

  10. Hydrogeology of the western part of the Salt River Valley area, Maricopa County, Arizona

    USGS Publications Warehouse

    Brown, James G.; Pool, D.R.

    1989-01-01

    The Salt River Valley is a major population and agricultural center of more than 3,000 mi2 in central Arizona (fig. 1). The western part of the Salt River Valley area (area of this report) covers about 1,500 mi2. The Phoenix metropolitan area with a population of more than 1.6 million in 1985 (Valley National Bank, 1987) is located within the valley. The watersheds of the Salt, Verde, and Agua Fria Rivers provide the valley with a reliable but limited surface-water supply that must be augmented with ground water even in years of plentiful rainfall. Large-scale ground-water withdrawals began in the Salt River Valley in the early part of the 20th century; between 1915 and 1983, the total estimated ground-water pumpage was 81 million acre-ft (U.S. Geological Survey, 1984). Because of the low average annual rainfall and high potential evapotranspiration, the principal sources of ground-water recharge are urban runoff, excess irrigation, canal seepage and surface-water flows during years of higher-than-normal rainfall. Withdrawals greatly exceed recharge and, in some area, ground-water levels have declines as much as 350 ft (Laney and other, 1978; Ross, 1978). In the study area, ground-water declines of more than 300 ft have occurred in Deer Valley and from Luke Air Force Base north to Beardsley. As a result, a large depression of the water table has developed west of Luke Air Force Base (fig. 2). Ground-water use has decreased in recent years because precipitation and surface-water supplies have been greater than normal. Increased precipitation also caused large quantities of runoff to be released into the normally dry Salt and Gila River channels. From February 1978 to June 1980, streamflow losses of at least 90,000 acre-ft occurred between Jointhead Dam near the east boundary of the study area and Gillespie Dam several miles southwest of the west edge of the study area (Mann and Rhone, 1983). Consequently, ground-water declines in a large part of the basin have

  11. Scaling relationships and concavity of small valley networks on Mars

    NASA Astrophysics Data System (ADS)

    Penido, Julita C.; Fassett, Caleb I.; Som, Sanjoy M.

    2013-01-01

    Valley networks are widely interpreted as the preserved erosional record of water flowing across the martian surface. The manner in which valley morphometric properties scale with drainage area has been widely examined on Earth. Earlier studies assessing these properties on Mars have suggested that martian valleys are morphometrically distinct from those on Earth. However, these earlier measurements were generally made on large valley systems because of the limited topographic data available. In this study, we determine the scaling properties of valley networks at smaller scales than have been previously assessed, using digital elevation models from the High Resolution Stereo Camera (HRSC). We find a Hack's law exponent of 0.74, larger than on Earth, and our measurements also reveal that individual small valleys have concave up, concave down, and quasi-linear longitudinal profiles, consistent with earlier studies of dissected terrain on Mars. However, for many valleys, widths are observed to increase downstream similarly to how they scale in terrestrial channels. The similarities and differences between valley networks on Mars and Earth are consistent with the idea that valleys on Mars are comparatively immature, and precipitation was a likely mechanism for delivering water to these networks.

  12. 27 CFR 9.100 - Mesilla Valley.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Mesilla Valley. 9.100 Section 9.100 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Mesilla Valley viticultural area is located within Dona Ana County, New Mexico, and El Paso County, Texas...

  13. 27 CFR 9.100 - Mesilla Valley.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Mesilla Valley. 9.100 Section 9.100 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Mesilla Valley viticultural area is located within Dona Ana County, New Mexico, and El Paso County, Texas...

  14. 27 CFR 9.78 - Ohio River Valley.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Valley.” (b) Approved maps. The approved maps for determining the boundary of the Ohio River Valley... boundary proceeds in a straight line westerly to the town of Dry Ridge in Grant County, Kentucky...

  15. Numerical Simulation of Nocturnal Drainage Flows in Idealized Valley-Tributary Systems.

    NASA Astrophysics Data System (ADS)

    O'Steen, Lance B.

    2000-11-01

    Numerical simulations of nocturnal drainage flow and transport in idealized valley-tributary systems are compared with the Atmospheric Science in Complex Terrain (ASCOT) meteorological field data and tracer studies from the Brush Creek valley of western Colorado. Much of the general valley-tributary flow behavior deduced from observations is qualitatively reproduced in the numerical results. The spatially complex, unsteady nature of the tributary flow found in the field data is also seen in the simulations. Oscillations in the simulated tributary flow are similar to some field observations. However, observed oscillations in the valley flow at the mouth of the tributary could not be reproduced in the numerical results. Thus, hypotheses of strongly coupled valley-tributary flow oscillations, based on field data, cannot be supported by these simulations. Along-valley mass flux calculations based on model results for the valley-tributary system indicate an increase of 5%-10% over a valley without a tributary. Enhanced valley mass fluxes were found from 8 km above the tributary to almost the valley mouth. However, the valley mass fluxes for topography with and without a tributary were nearly equal at the valley outflow. ASCOT field data suggested a tributary mass flow contribution of 5%-15% for a Brush Creek tributary of similar drainage area to the model tributary employed here. Numerical simulations of transport in the nocturnal valley-tributary flow strongly support ASCOT tracer studies in the Pack Canyon tributary of Brush Creek. These results suggest that the valley-tributary interaction can significantly increase plume dispersion under stable conditions. Overall, the simulation results presented here indicate that simple terrain geometries are able to capture many of the salient features of drainage flow in real valley-tributary systems.

  16. The Valley Networks on Mars

    NASA Astrophysics Data System (ADS)

    Gulick, V. C.

    2002-12-01

    Despite three decades of exploration, the valley networks on Mars still seem to raise more questions than they answer. Valley systems have formed in the southern highlands, along some regions of the dichotomy boundary and the south rim of Valles Marineris, around the rim of some impact craters, and on the flanks of some volcanoes. They are found on some of the oldest and youngest terrains as well as on intermediate aged surfaces. There is surprisingly little consensus as to the formation and the paleoclimatic implications of the valley networks. Did the valleys require a persistent solar-driven atmospheric hydrological cycle involving precipitation, surface runoff, infiltration and groundwater outflow as they typically do on Earth? Or are they the result of magmatic or impact-driven thermal cycling of ground water involving persistent outflow and subsequent runoff? Are they the result of some other process(es)? Ground-water sapping, surface-water runoff, debris flows, wind erosion, and formation mechanisms involving other fluids have been proposed. Until such basic questions as these are definitively answered, their significance for understanding paleoclimatic change on Mars remains cloudy. I will review what is known about valley networks using data from both past and current missions. I will discuss what we have learned about their morphology, environments in which they formed, their spatial and temporal associations, possible formation mechanisms, relation to outflow channel and gully formation, as well as the possible implications for past climate change on Mars. Finally I will discuss how future, meter to submeter scale imaging and other remote sensing observations may shed new light on the debate over the origin of these enigmatic features.

  17. Evidence for hot Mississippi Valley-type brines in the Reelfoot Rift complex, south-central United States, in Late Pennsylvanian-Early Permian

    USGS Publications Warehouse

    Leach, D.L.; Apodaca, L.E.; Repetski, J.E.; Powell, J.W.; Rowan, E.L.

    1997-01-01

    Petrographic and fluid inclusion studies of sparry dolomite cement from Upper Cambrian to Lower Ordovician rocks and conodont thermal-alteration indices provide evidence that hot mississippi valley-type brines were once present in the Reelfoot Rift complex. The cathodoluminescent microstratigraphy of sparry dolomite cement in the Reelfoot Rift resembles that of sparry dolomite cement associated with widespread mississippi valley-type deposition in the Ozark region. If correlative cathodoluminescent zones in the sparry dolomite from the Ozark and Reelfoot Rift regions indicate broadly contemporaneous dolomite deposition, then the results show that the Ozark MVT-type hydrothermal system extended into the Reelfoot region and onto the western flank of the Nashville Dome. Independent evidence supports migration of MVT-type brines into the Ozark region from the Reelfoot Rift complex in late Paleozoic time.

  18. Statecraft and expansionary dynamics: A Virú outpost at Huaca Prieta, Chicama Valley, Peru

    PubMed Central

    Millaire, Jean-François; Prieto, Gabriel; Surette, Flannery; Redmond, Elsa M.; Spencer, Charles S.

    2016-01-01

    Interpolity interaction and regional control were central features of all early state societies, taking the form of trade—embedded in political processes to varying degrees—or interregional conquest strategies meant to expand the polity’s control or influence over neighboring territories. Cross-cultural analyses of early statecraft suggest that territorial expansion was an integral part of the process of primary state formation, closely associated with the delegation of authority to subordinate administrators and the construction of core outposts of the state in foreign territories. We report here on a potential case of a core outpost, associated with the early Virú state, at the site of Huaca Prieta in the Chicama Valley, located 75 km north of the Virú state heartland on the north coast of Peru. This site is discussed in the context of other possible Virú outposts in the Moche Valley, Pampa La Cruz, and Huaca Las Estrellas, and as part of a broader reflection on expansionary dynamics and statecraft. PMID:27671633

  19. Statecraft and expansionary dynamics: A Virú outpost at Huaca Prieta, Chicama Valley, Peru.

    PubMed

    Millaire, Jean-François; Prieto, Gabriel; Surette, Flannery; Redmond, Elsa M; Spencer, Charles S

    2016-10-11

    Interpolity interaction and regional control were central features of all early state societies, taking the form of trade-embedded in political processes to varying degrees-or interregional conquest strategies meant to expand the polity's control or influence over neighboring territories. Cross-cultural analyses of early statecraft suggest that territorial expansion was an integral part of the process of primary state formation, closely associated with the delegation of authority to subordinate administrators and the construction of core outposts of the state in foreign territories. We report here on a potential case of a core outpost, associated with the early Virú state, at the site of Huaca Prieta in the Chicama Valley, located 75 km north of the Virú state heartland on the north coast of Peru. This site is discussed in the context of other possible Virú outposts in the Moche Valley, Pampa La Cruz, and Huaca Las Estrellas, and as part of a broader reflection on expansionary dynamics and statecraft.

  20. Capturing and Explaining Preference Heterogeneity for Wetland Management Options in the Kilombero Valley, Tanzania

    NASA Astrophysics Data System (ADS)

    Speelman, Stijn; Mombo, Felister; Vandermeulen, Valerie; Phillip, Damas; Van Huylenbroeck, Guido

    2015-01-01

    Wetland degradation has recently received considerable research attention. Although wetlands are valuable ecosystems, their actual value is difficult to measure because the services they provide often do not have market values. The current study seeks to investigate the preferences for wetland management options in the Kilombero Valley, central Tanzania using choice modeling. The results show that both respondents from the Kilombero Valley and Morogoro Municipality desire improvements in the condition of the wetlands. This indicates that the ongoing degradation is not socially optimal. A second finding is that the preferences for wetland conservation are heterogeneous and can be linked to livelihood characteristics. Communities living in the area, for example, are highly dependent on the wetland for their livelihood and would be impacted by conservation measures. Therefore, in order to reduce the pressure on wetlands, it is necessary and imperative to explore the options for alternative income-generating activities or to focus, for example, on technologies to improve efficiency and effectiveness in crop production.