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Sample records for canyon ta-10 site

  1. Environmenal analysis of the Bayo Canyon (TA-10) Site, Los Alamos, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ferenbaugh, R.W.; Buhl, T.E.; Stoker, A.K.; Hansen, W.R.

    1982-05-01

    The radiological survey of the old TA-10 site in Bayo Canyon found low levels of surface contamination in the vicinity of the firing sites and subsurface contamination in the old waste disposal area. The three alternatives proposed for the site are: (1) to take no action; (2) to restrict usage of the area of subsurface contamination to activities that cause no subsurface disturbance (minimal action); and (3) to remove the subsurface conamination to levels below the working criteria. Dose calculations indicate that doses from surface contamination for recreational users of the canyon, permanent residents, and construction workers and doses for workers involved in excavation of contaminated soil under the clean up alternative are only small percentages of applicable guidelines. No environmental impacts are associated with either the no-action or minimal action alternatives. The impact associated with the cleanup alternative is small, especially considering that the area already has been affected by the original TA-10 decommissioning action, but nevertheless, the preferred alternative is the minimal action alternative, where 0.6 hectare of land is restricted to surface activities. This leaves the rest of the canyon available for development with up to 400 homes. The restricted area can be used for a park, tennis courts, etc., and the /sup 90/Sr activity will decay to levels permitting unrestricted usage in about 160 y.

  2. Environmenal analysis of the Bayo Canyon (TA-10) Site, Los Alamos, New Mexico

    International Nuclear Information System (INIS)

    The radiological survey of the old TA-10 site in Bayo Canyon found low levels of surface contamination in the vicinity of the firing sites and subsurface contamination in the old waste disposal area. The three alternatives proposed for the site are: (1) to take no action; (2) to restrict usage of the area of subsurface contamination to activities that cause no subsurface disturbance (minimal action); and (3) to remove the subsurface conamination to levels below the working criteria. Dose calculations indicate that doses from surface contamination for recreational users of the canyon, permanent residents, and construction workers and doses for workers involved in excavation of contaminated soil under the clean up alternative are only small percentages of applicable guidelines. No environmental impacts are associated with either the no-action or minimal action alternatives. The impact associated with the cleanup alternative is small, especially considering that the area already has been affected by the original TA-10 decommissioning action, but nevertheless, the preferred alternative is the minimal action alternative, where 0.6 hectare of land is restricted to surface activities. This leaves the rest of the canyon available for development with up to 400 homes. The restricted area can be used for a park, tennis courts, etc., and the 90Sr activity will decay to levels permitting unrestricted usage in about 160 y

  3. Environmental assessment: Davis Canyon site, Utah

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1986-05-01

    In February 1983, the US Department of Energy (DOE) identified the Davis Canyon site in Utah as one of the nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high-level radioactive waste. To determine their suitability, the Davis Canyon site and the eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. These evaluations were reported in draft environmental assessments (EAs), which were issued for public review and comment. After considering the comments received on the draft EAs, the DOE prepared the final EA. The Davis Canyon site is in the Paradox Basin, which is one of five distinct geohydrologic settings considering for the first repository. This setting contains one other potentially acceptable site -- the Lavender Canyon site. Although the Lavender Canyon site is suitable for site characterization, the DOE has concluded that the Davis Canyon site is the preferred site in the Paradox Basin. On the basis of the evaluations reported in this EA, the DOE has found that the Davis Canyon site is not disqualified under the guidelines. Furthermore, the DOE has found that the site is suitable for site characterization because the evidence does not support a conclusion that the site will not be able to meet each of the qualifying conditions specified in the guidelines. On the basis of these findings, the DOE is nominating the Davis Canyon site as one of five sites suitable for characterization.

  4. Environmental assessment: Davis Canyon site, Utah

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1986-05-01

    In February 1983, the US Department of Energy (DOE) identified the Davis Canyon site in Utah as one of the nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high- level radioactive waste. To determine their suitability, the Davis Canyon site and the eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. These evaluations were reported in draft environmental assessments (EAs), which were issued for public review and comment. After considering the comments received on the draft EAs, the DOE prepared the final EA. The Davis Canyon site is in the Paradox Basin, which is one of five distinct geohydrologic settings considered for the first repository. This setting contains one other potentially acceptable site -- the Lavender Canyon site. Although the Lavender Canyon site is suitable for site characterization, the DOE has concluded that the Davis Canyon site is the preferred site in the Paradox Basin. On the basis of the evaluations reported in this EA, the DOE has found that the Davis Canyon site is not disqualified under the guidelines. Furthermore, the DOE has found that the site is suitable for site characterization because the evidence does not support a conclusion that the site will not be able to meet each of the qualifying conditions specified in the guidelines. On the basis of these findings, the DOE is nominating the Davis Canyon site as one of the five sites suitable for characterization.

  5. Environmental assessment: Davis Canyon site, Utah

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1986-05-01

    In February 1983, the US Department of Energy (DOE) identified the Davis Canyon site in Utah as one of the nine potentially acceptable sites for a mined geologic repository for spent nuclear fuel and high-level radioactive waste. To determine their suitability, the Davis Canyon site and the eight other potentially acceptable sites have been evaluated in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. These evaluations were reported in draft environmental assessments (EAs), which were issued for public review and comment. After considering the comments received on the draft EAs, the DOE prepared the final EA. The Davis Canyon site is in the Paradox Basin, which is one of five distinct geohydrologic settings considered for the first repository. This setting contains one other potentially acceptable site -- the Lavender Canyon site. Although the Lavender Canyon site is suitable for site characterization, the DOE has concluded that the Davis Canyon site is the preferred site in the Paradox Basin. On the basis of the evaluations reported in this EA, the DOE has found that the Davis Canyon site is not disqualified under the guidelines. Furthermore, the DOE has fond that the site is suitable for site characterization because the evidence does not support a conclusion that the site will not be able to meet each of the qualifying conditions specified in the guidelines. On the basis of these findings, the DOE is nominating the Davis Canyon site as one of five sites suitable for characterization. 181 figs., 175 tabs.

  6. Noise source emissions, Davis Canyon site, Utah

    International Nuclear Information System (INIS)

    This report has been prepared for the purpose of documenting the development of the data provided to the Repository Project Management (RPM) organization. The data provided encompass all phases of activity, from site preparation through the exploratory shaft facility (ESF) and repository construction and operation, and decommissioning. Noise environments expected from construction and operation of transportation corridors associated with the activity were also modeled. The data for the construction of transportation corridors were provided by Bechtel National, Inc. Use of the quietest equipment available within the proven state of the art was assumed, as was the use of acoustical enclosures to the extent practical. The programmatic assumptions are based on the noise-sensitive nature of the Canyonlands National Park. Another feature of the data is the use of 1/3-octave-band rather than 1/1-octave-band resolution of emission spectra. This was done to permit evaluation of audibility of sounds reaching the park

  7. Sutton: Archaeological Investigations at the Owl Canyon Site (CA-SBR-3801), Mojave Desert, California

    OpenAIRE

    Basgall, Mark E

    1987-01-01

    Archaeological Investigations at the Owl Canyon Site (CA-SBR-3801), Mojave Desert, California Mark Q. Sutton. Salinas: Coyote Press Archives of California Prehistory No. 9, 1986, 72 pp., 17 figures, 3 Appendices, $3.95 (paper).

  8. Topographic change detection at select archeological sites in Grand Canyon National Park, Arizona, 2007–2010

    Science.gov (United States)

    Collins, Brian D.; Corbett, Skye C.; Fairley, Helen C.; Minasian, Diane L.; Kayen, Robert; Dealy, Timothy P.; Bedford, David R.

    2012-01-01

    Human occupation in Grand Canyon, Arizona, dates from at least 11,000 years before present to the modern era. For most of this period, the only evidence of human occupation in this iconic landscape is provided by archeological sites. Because of the dynamic nature of this environment, many archeological sites are subject to relatively rapid topographic change. Quantifying the extent, magnitude, and cause of such change is important for monitoring and managing these archeological sites. Such quantification is necessary to help inform the continuing debate on whether and how controlled releases from Glen Canyon Dam, located immediately upstream of Grand Canyon National Park, are affecting site erosion rates, artifact transport, and archeological resource preservation along the Colorado River in Grand Canyon. Although long-term topographic change resulting from a variety of natural processes is inherent in the Grand Canyon region, continued erosion of archeological sites threatens both the archeological resources and our future ability to study evidence of past cultural habitation. Thus, this subject is of considerable interest to National Park Service managers and other stakeholders in the Glen Canyon Dam Adaptive Management Program. Understanding the causes and effects of archeological site erosion requires a knowledge of several factors, including the location, timing, and magnitude of the changes occurring in relation to archeological resources, the rates of change, and the relative contribution of potential causes. These potential causes include sediment depletion associated with managed flows from Glen Canyon Dam, site-specific weather and overland flow patterns, visitor impacts, and long-term regional climate change. To obtain this information, highly accurate, spatially specific data are needed from sites undergoing change. Using terrestrial lidar techniques, and building upon three previous surveys of archeological sites performed in 2006 and 2007, we

  9. RESEARCH AND DEVELOPMENT ACTIVITIES AT SAVANNAH RIVER SITE'S H CANYON FACILITY

    Energy Technology Data Exchange (ETDEWEB)

    Sexton, Lindsay; Fuller, Kenneth

    2013-07-09

    The Savannah River Site's (SRS) H Canyon Facility is the only large scale, heavily shielded, nuclear chemical separations plant still in operation in the U.S. The facility's operations historically recovered uranium-235 (U-235) and neptunium-237 (Np-237) from aluminum-clad, enriched-uranium fuel tubes from Site nuclear reactors and other domestic and foreign research reactors. Today the facility, in conjunction with HB Line, is working to provide the initial feed material to the Mixed Oxide Facility also located on SRS. Many additional campaigns are also in the planning process. Furthermore, the facility has started to integrate collaborative research and development (R&D) projects into its schedule. H Canyon can serve as the appropriate testing location for many technologies focused on monitoring the back end of the fuel cycle, due to the nature of the facility and continued operation. H Canyon, in collaboration with the Savannah River National Laboratory (SRNL), has been working with several groups in the DOE complex to conduct testing demonstrations of novel technologies at the facility. The purpose of conducting these demonstrations at H Canyon will be to demonstrate the capabilities of the emerging technologies in an operational environment. This paper will summarize R&D testing activities currently taking place in H Canyon and discuss the possibilities for future collaborations.

  10. Topographic Change Detection at Select Archeological Sites in Grand Canyon National Park, Arizona, 2006-2007

    Science.gov (United States)

    Collins, Brian D.; Minasian, Diane L.; Kayen, Robert

    2009-01-01

    Topographic change of archeological sites within the Colorado River corridor of Grand Canyon National Park (GCNP) is a subject of interest to National Park Service managers and other stakeholders in the Glen Canyon Dam Adaptive Management Program. Although long-term topographic change resulting from a variety of natural processes is typical in the Grand Canyon region, a continuing debate exists on whether and how controlled releases from Glen Canyon Dam, located immediately upstream of GCNP, are impacting rates of site erosion, artifact transport, and the preservation of archeological resources. Continued erosion of archeological sites threatens both the archeological resources and our future ability to study evidence of past cultural habitation. Understanding the causes and effects of archaeological site erosion requires a knowledge of several factors including the location and magnitude of the changes occurring in relation to archeological resources, the rate of the changes, and the relative contribution of several potential causes, including sediment depletion associated with managed flows from Glen Canyon Dam, site-specific weather patterns, visitor impacts, and long-term climate change. To obtain this information, highly accurate, spatially specific data are needed from sites undergoing change. Using terrestrial lidar data collection techniques and novel TIN- and GRID-based change-detection post-processing methods, we analyzed topographic data for nine archeological sites. The data were collected using three separate data collection efforts spanning 16 months (May 2006 to September 2007). Our results documented positive evidence of erosion, deposition, or both at six of the nine sites investigated during this time interval. In addition, we observed possible signs of change at two of the other sites. Erosion was concentrated in established gully drainages and averaged 12 cm to 17 cm in depth with maximum depths of 50 cm. Deposition was concentrated at specific

  11. Long-term surveillance plan for the Bodo Canyon Disposal Site, Durango, Colorado. Revision 1

    International Nuclear Information System (INIS)

    This long-term surveillance plan (LTSP) for the Uranium Mill Tailings Remedial Act on (UMTRA) Project Bodo Canyon disposal site at Durango, Colorado, describes the surveillance activities for the disposal site. The US Department of Energy (DOE) will carry out these activities to ensure that the disposal call continues to function as designed This LTSP was prepared as a requirement for DOE acceptance under the US Nuclear Regulatory Commission (NRC) general license for custody and long-term care of residual radioactive materials (RRM) from processing uranium ore. This LTSP documents that the land and interests are owned by the United States and details how long-term care of the disposal site will be carried out. It is based on the DOE's Guidance for Implementing the UMTRA Project Long-term Surveillance Program (DOE, 1992a). Following the introduction, contents of this report include the following: site final condition; site drawings and photographs; permanent site surveillance features; ground water monitoring; annual site inspections; unscheduled inspections; custodial maintenance; corrective action; record keeping and reporting requirements; emergency notification and reporting; quality assurance; personal health and safety; list of contributions; and references

  12. Long-term surveillance plan for the Bodo Canyon Disposal Site, Durango, Colorado. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-11-01

    This long-term surveillance plan (LTSP) for the Uranium Mill Tailings Remedial Act on (UMTRA) Project Bodo Canyon disposal site at Durango, Colorado, describes the surveillance activities for the disposal site. The US Department of Energy (DOE) will carry out these activities to ensure that the disposal call continues to function as designed This LTSP was prepared as a requirement for DOE acceptance under the US Nuclear Regulatory Commission (NRC) general license for custody and long-term care of residual radioactive materials (RRM) from processing uranium ore. This LTSP documents that the land and interests are owned by the United States and details how long-term care of the disposal site will be carried out. It is based on the DOE`s Guidance for Implementing the UMTRA Project Long-term Surveillance Program (DOE, 1992a). Following the introduction, contents of this report include the following: site final condition; site drawings and photographs; permanent site surveillance features; ground water monitoring; annual site inspections; unscheduled inspections; custodial maintenance; corrective action; record keeping and reporting requirements; emergency notification and reporting; quality assurance; personal health and safety; list of contributions; and references.

  13. SeepC: Preliminary Characterization of Atlantic Margin Seep Ecosystems from Norfolk Canyon to New England Seep Sites.

    Science.gov (United States)

    Turner, P. J.; Ball, B.; Cole, E.; LaBella, A.; Wagner, J.; Van Dover, C. L.; Skarke, A. D.; Ruppel, C. D.

    2015-12-01

    Since 2013, more than 500 seep sites have been located along the continental margin of the eastern US using acoustic signals of gas plumes in the water column. During a July 2015 R/V Atlantis expedition, scientists used the submersible Alvin to explore seep sites at depths of 300 to 1500 m. Study sites ranged from Norfolk Canyon north to New England Seep 2 and included Baltimore, Veatch, and Shallop Canyon sites, as well as new unnamed sites between Norfolk and Baltimore Canyons. Mussels dominated the seep sites (cf ''Bathymodiolus'' childressi) but only small populations (invertebrate species at the newly explored seeps was the red crab, Chaceon sp. and the rock crab, Cancer sp. These crabs are not seep endemic but they were especially abundant at the seeps and were observed to feed and mate on the seep grounds. Molecular tools will be used to explore the genetic structure of mussel populations from Norfolk to New England seeps, and stable isotope methods will be used to test for differences among sites in the source of carbon used by mussels. Alvin video transects and photo-mosaics will be used to collect data on macrofauna associated with seeps and to test the hypothesis that shallow seeps (300-500m) support more diverse assemblages than deep sites (1000-1500m).

  14. High-resolution topography and geomorphology of select archeological sites in Glen Canyon National Recreation Area, Arizona

    Science.gov (United States)

    Collins, Brian D.; Corbett, Skye C.; Sankey, Joel B.; Fairley, Helen C.

    2014-01-01

    Along the Colorado River corridor between Glen Canyon Dam and Lees Ferry, Arizona, located some 25 km downstream from the dam, archaeological sites dating from 8,000 years before present through the modern era are located within and on top of fluvial and alluvial terraces of the prehistorically undammed river. These terraces are known to have undergone significant erosion and retreat since emplacement of Glen Canyon Dam in 1963. Land managers and policy makers associated with managing the flow of the Colorado River are interested in understanding how the operations of Glen Canyon Dam have affected the archeological sites associated with these terraces and how dam-controlled flows currently interact with other landscape-shaping processes. In 2012, the U.S. Geological Survey initiated a research project in Glen Canyon to study the types and causes of erosion of the terraces. This report provides the first step towards this understanding by presenting comparative analyses on several types of high-resolution topographic data (airborne lidar, terrestrial lidar, and airborne photogrammetry) that can be used in the future to document and analyze changes to terrace-based archaeological sites. Herein, we present topographic and geomorphologic data of four archaeological sites within a 14 km segment of Glen Canyon using each of the three data sources. In addition to comparing each method’s suitability for adequately representing the topography of the sites, we also analyze the data within each site’s context and describe the geomorphological processes responsible for erosion. Our results show that each method has its own strengths and weaknesses, and that terrestrial and airborne lidar are essentially interchangeable for many important topographic characterization and monitoring purposes. However, whereas terrestrial lidar provides enhanced capacity for feature recognition and gully morphology delineation, airborne methods (whether by way of laser or optical sensors) are

  15. Site descriptions: Cypress Creek, Davis Canyon, Deaf Smith, Hanford Reference, Lavender Canyon, Richton Dome, Swisher, Vacherie Dome, Yucca Mountain. Revision

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1986-04-01

    The following information is given about the various sites: location (state and county), terrain, climate, weather, endangered plants and animals; nearest town, population, nearest railway, nearest interstate highway, economy, density within 50 miles, owners, and historical sites. (LM)

  16. SAVANNAH RIVER SITE'S H-CANYON FACILITY: RECOVERY AND DOWN BLEND URANIUM FOR BENEFICIAL USE

    Energy Technology Data Exchange (ETDEWEB)

    Magoulas, V.

    2013-05-27

    For over fifty years, the H Canyon facility at the Savannah River Site (SRS) has performed remotely operated radiochemical separations of irradiated targets to produce materials for national defense. Although the materials production mission has ended, the facility continues to play an important role in the stabilization and safe disposition of proliferable nuclear materials. As part of the US HEU Disposition Program, SRS has been down blending off-specification (off-spec) HEU to produce LEU since 2003. Off-spec HEU contains fission products not amenable to meeting the American Society for Testing and Material (ASTM) commercial fuel standards prior to purification. This down blended HEU material produced 301 MT of ~5% enriched LEU which has been fabricated into light water reactor fuel being utilized in Tennessee Valley Authority (TVA) reactors in Tennessee and Alabama producing economic power. There is still in excess of ~10 MT of off-spec HEU throughout the DOE complex or future foreign and domestic research reactor returns that could be recovered and down blended for beneficial use as either ~5% enriched LEU, or for use in subsequent LEU reactors requiring ~19.75% enriched LEU fuel.

  17. Integrated Project Management Planning for the Deactivation of the Savannah River Site F-Canyon Complex

    Energy Technology Data Exchange (ETDEWEB)

    Clark, T.G.

    2000-12-01

    This paper explains the planning process that is being utilized by the Westinghouse Savannah River Company to take the F-Canyon Complex facilities from operations to a deactivated condition awaiting final decommissioning.

  18. Hydrologic characterization of the Fry Canyon, Utah site prior to field demonstration of reactive chemical barriers to control radionuclide and trace-element contamination in ground water

    Energy Technology Data Exchange (ETDEWEB)

    Naftz, D.L.; Freethey, G.W. [Geological Survey, Salt Lake City, UT (United States); Davis, J.A. [Geological Survey, Menlo Park, CA (United States)] [and others

    1997-12-31

    The Fry Canyon Site in southeastern Utah has been selected as a long term demonstration site to assess the performance of selected reaction barrier technologies for the removal of uranium and other trace elements from ground water. Objectives include site characterization and evaluation of barrier technologies.

  19. Modified fused silicide coatings for tantalum (Ta-10W) reentry heat shields

    Science.gov (United States)

    Packer, C. M.; Perkins, R. A.

    1973-01-01

    Results are presented of a program of research to develop a reliable, high performance, fused slurry silicide coating for the Ta-10W alloy. The effort was directed toward developing new and improved formulations for use at 2600 to 2800 F (1700 to 1811 K) in an atmospheric reentry thermal protection system with a 100-mission capability. Based on a thorough characterization of isothermal and cyclic oxidation behavior, bend transition temperatures, room- and elevated-temperature tensile properties, and creep behavior, a 2.5 Mn-33Ti-64.5Si coating (designated MTS) provides excellent protection for the Ta-10W alloy in simulated reentry environments. An extensive analysis of the oxidation behavior and characteristics of the MTS coating in terms of fundamental mechanisms also is presented.

  20. Major-element geochemistry of the Silent Canyon--Black Mountain peralkaline volcanic centers, northwestern Nevada Test Site: applications to an assessment of renewed volcanism

    International Nuclear Information System (INIS)

    The Silent Canyon and Black Mountain volcanic centers are located in the northern part of the Nevada Test Site. The Silent Canyon volcanic center is a buried cauldron complex of Miocene age (13 to 15 m.y.). Black Mountain volcanic center is an elliptical-shaped cauldron complex of late Miocene age. The lavas and tuffs of the two centers comprise a subalkaline-peralkaline association. Rock types range from quartz normative subalkaline trachyte and rhyolite to peralkaline commendite. The Gold Flat Member of the Thirsty Canyon Tuff (Black Mountain) is a pantellerite. The major-element geochemistry of the Black Mountain--Silent Canyon volcanic centers differ in the total range and distribution of SiO2, contents, the degree of peralkalinity (molecular Na2O + K2O > Al2O3) and in the values of total iron and alumina through the range of rock types. These differences indicate that the suites were unrelated and evolved from differing magma bodies. The Black Mountain volcanic cycle represents a renewed phase of volcanism following cessation of the Timber Mountain--Silent Canyon volcanic cycles. Consequently, there is a small but numerically incalculable probability of recurrence of Black Mountain-type volcanism within the Nevada Test Site region. This represents a potential risk with respect to deep geologic storage of high-level radioactive waste at the Nevada Test Site

  1. Conditions and processes affecting sand resources at archeological sites in the Colorado River corridor below Glen Canyon Dam, Arizona

    Science.gov (United States)

    East, Amy E.; Collins, Brian D.; Sankey, Joel B.; Corbett, Skye C.; Fairley, Helen C.; Caster, Joshua

    2016-05-17

    This study examined links among fluvial, aeolian, and hillslope geomorphic processes that affect archeological sites and surrounding landscapes in the Colorado River corridor downstream from Glen Canyon Dam, Arizona. We assessed the potential for Colorado River sediment to enhance the preservation of river-corridor archeological resources through aeolian sand deposition or mitigation of gully erosion. By identifying locally prevailing wind directions, locations of modern sandbars, and likely aeolian-transport barriers, we determined that relatively few archeological sites are now ideally situated to receive aeolian sand supply from sandbars deposited by recent controlled floods. Whereas three-fourths of the 358 river-corridor archeological sites we examined include Colorado River sediment as an integral component of their geomorphic context, only 32 sites currently appear to have a high degree of connectivity (coupled interactions) between modern fluvial sandbars and sand-dominated landscapes downwind. This represents a substantial decrease from past decades, as determined by aerial-photograph analysis. Thus, we infer that recent controlled floods have had a limited, and declining, influence on archeological-site preservation.

  2. Quantifying uranium transport rates and storage of fluvially eroded mine tailings from a historic mine site in the Grand Canyon Region

    Science.gov (United States)

    Skalak, K.; Benthem, A. J.; Walton-Day, K. E.; Jolly, G.

    2015-12-01

    The Grand Canyon region contains a large number of breccia pipes with economically viable uranium, copper, and silver concentrations. Mining in this region has occurred since the late 19th century and has produced ore and waste rock having elevated levels of uranium and other contaminants. Fluvial transport of these contaminants from mine sites is a possibility, as this arid region is susceptible to violent storms and flash flooding which might erode and mobilize ore or waste rock. In order to assess and manage the risks associated with uranium mining, it is important to understand the transport and storage rates of sediment and uranium within the ephemeral streams of this region. We are developing a 1-dimensional sediment transportation model to examine uranium transport and storage through a typical canyon system in this region. Our study site is Hack Canyon Mine, a uranium and copper mine site, which operated in the 1980's and is currently experiencing fluvial erosion of its waste rock repository. The mine is located approximately 40km upstream from the Colorado River and is in a deep, narrow canyon with a small watershed. The stream is ephemeral for the upper half of its length and sediment is primarily mobilized during flash flood events. We collected sediment samples at 110 locations longitudinally through the river system to examine the distribution of uranium in the stream. Samples were sieved to the sand size and below fraction (waste rock and contribute to understanding the risks associated with fluvial mobilization of uranium mine waste.

  3. Response of a transmission tower-line system at a canyon site to spatially varying ground motions

    Institute of Scientific and Technical Information of China (English)

    Hong-nan LI; Feng-long BAI; Li TIAN; Hong HAO

    2011-01-01

    Collapses of transmission towers were often observed in previous large earthquakes such as the Chi-Chi earthquake in Taiwan and Wenchuan earthquake in Sichuan, China. These collapses were partially caused by the pulling forces from the transmission lines generated from out-of-phase responses of the adjacent towers owing to spatially varying earthquake ground motions. In this paper, a 3D finite element model of the transmission tower-line system is established considering the geometric nonlinearity of transmission lines. The nonlinear responses of the structural system at a canyon site are analyzed subjected to spatially varying ground motions. The spatial variations of ground motion associated with the wave passage, coherency loss, and local site effects are given. The spatially varying ground motions are simulated stochastically based on an empirical coherency loss function and a filtered Tajimi-Kanai power spectral density function. The site effect is considered by a transfer function derived from ID wave propagation theory. Compared with structural responses calculated using the uniform ground motion and delayed excitations, numerical results indicate that seismic responses of transmission towers and power lines are amplified when considering spatially varying ground motions including site effects. Each factor of ground motion spatial variations has a significant effect on the seismic response of the structure, especially for the local site effect. Therefore, neglecting the earthquake ground motion spatial variations may lead to a substantial underestimation of the response of transmission tower-line system during strong earthquakes. Each effect of ground motion spatial variations should be incorporated in seismic analysis of the structural system.

  4. Conceptual Model of the Geometry and Physics of Water Flow in a Fractured Basalt Vadose Zone: Box Canyon Site, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Faybishenko, Boris [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Doughty, Christine [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Steiger, Michael [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Long, Jane C.S. [Univ. of Nevada, Reno, NV (US). Mackay School of Mines; Wood, Tom [Parsons Engineering, Inc., Idaho Falls, ID (United States); Jacobsen, Janet [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lore, Jason [Stanford Univ., CA (United States); Zawislanski, Peter T. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    1999-03-01

    A conceptual model of the geometry and physics of water flow in a fractured basalt vadose zone was developed based on the results of lithological studies and a series of ponded infiltration tests conducted at the Box Canyon site near the Idaho National Engineering and Environmental Laboratory (INEEL) in Idaho. The infiltration tests included one two-week test in 1996, three two-day tests in 1997, and one four-day test in 1997. For the various tests, initial infiltration rates ranged from 4.1 cm/day to 17.7 cm/day and then decreased with time, presumably due to mechanical or microbiological clogging of fractures and vesicularbasalt in the near-surface zone, as well as the effect of entrapped air. The subsurface moisture redistribution was monitored with tensiometers, neutron logging, time domain reflectrometry and ground penetrating radar. A conservative tracer, potassium bromide, was added to the pond water at a concentration of 3 g/L to monitor water flow with electrical resistivity probes and water sampling. Analysis of the data showed evidence of preferential flow rather than the propagation of a uniform wetting front. We propose a conceptual model describing the saturation-desaturation behavior of the basalt, in which rapid preferential flow through vertical column-bounding fractures occurs from the surface to the base of the basalt flow. After the rapid wetting of column-bounding fractures, a gradual wetting of other fractures and the basalt matrix occurs. Fractures that are saturated early in the tests may become desaturated thereafter, which we attribute to the redistribution of water between fractures and matrix. Lateral movement of water was also observed within a horizontal central fracture zone and rubble zone, which could have important implications for contaminant accumulation at contaminated sites.

  5. Geology, geochemistry, and geophysics of the Fry Canyon uranium/copper project site, southeastern Utah - Indications of contaminant migration

    Science.gov (United States)

    Otton, James K.; Zielinski, Robert A.; Horton, Robert J.

    2010-01-01

    The Fry Canyon uranium/copper project site in San Juan County, southeastern Utah, was affected by the historical (1957-68) processing of uranium and copper-uranium ores. Relict uranium tailings and related ponds, and a large copper heap-leach pile at the site represent point sources of uranium and copper to local soils, surface water, and groundwater. This study was designed to establish the nature, extent, and pathways of contaminant dispersion. The methods used in this study are applicable at other sites of uranium mining, milling, or processing. The uranium tailings and associated ponds sit on a bench that is as much as 4.25 meters above the level of the adjacent modern channel of Fry Creek. The copper heap leach pile sits on bedrock just south of this bench. Contaminated groundwater from the ponds and other nearby sites moves downvalley and enters the modern alluvium of adjacent Fry Creek, its surface water, and also a broader, deeper paleochannel that underlies the modern creek channel and adjacent benches and stream terraces. The northern extent of contaminated groundwater is uncertain from geochemical data beyond an area of monitoring wells about 300 meters north of the site. Contaminated surface water extends to the State highway bridge. Some uranium-contaminated groundwater may also enter underlying bedrock of the Permian Cedar Mesa Sandstone along fracture zones. Four dc-resistivity surveys perpendicular to the valley trend were run across the channel and its adjacent stream terraces north of the heap-leach pile and ponds. Two surveys were done in a small field of monitoring wells and two in areas untested by borings to the north of the well field. Bedrock intercepts, salt distribution, and lithologic information from the wells and surface observations in the well field aided interpretation of the geophysical profiles there and allowed interpretation of the two profiles not tested by wells. The geophysical data for the two profiles to the north of the

  6. Managing the nation`s nuclear waste. Site descriptions: Cypress Creek, Davis Canyon, Deaf Smith, Hanford Reference, Lavender Canyon, Richton Dome, Swisher, Vacherie Dome, and Yucca Mountain

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1985-12-31

    In 1982, the Congress enacted the Nuclear Waste Policy Act (Public Law 97-425), which established a comprehensive national program directed toward siting, constructing, and operating geologic repositories for the permanent disposal of high-level radioactive waste. In February 1983, the United States Department of Energy (DOE) identified the nine referenced repository locations as potentially acceptable sites for a mined geologic repository. These sites have been evaluated in accordance with the DOE`s General Guidelines for the Recommendation of Sites for Nuclear Waste Repositories. The DOE findings and determinations are based on the evaluations contained in the draft Environmental Assessments (EA). A final EA will be prepared after considering the comments received on the draft EA. The purpose of this document is to provide the public with specific site information on each potential repository location.

  7. Geologic Investigation of a Potential Site for a Next-Generation Reactor Neutrino Oscillation Experiment -- Diablo Canyon, San Luis Obispo County, CA

    Energy Technology Data Exchange (ETDEWEB)

    Onishi, Celia Tiemi; Dobson, Patrick; Nakagawa, Seiji; Glaser, Steven; Galic, Dom

    2004-06-11

    This report provides information on the geology and selected physical and mechanical properties of surface rocks collected at Diablo Canyon, San Luis Obispo County, California as part of the design and engineering studies towards a future reactor neutrino oscillation experiment. The main objective of this neutrino project is to study the process of neutrino flavor transformation or neutrino oscillation by measuring neutrinos produced in the fission reactions of a nuclear power plant. Diablo Canyon was selected as a candidate site because it allows the detectors to be situated underground in a tunnel close to the source of neutrinos (i.e., at a distance of several hundred meters from the nuclear power plant) while having suitable topography for shielding against cosmic rays. The detectors have to be located underground to minimize the cosmic ray-related background noise that can mimic the signal of reactor neutrino interactions in the detector. Three Pliocene-Miocene marine sedimentary units dominate the geology of Diablo Canyon: the Pismo Formation, the Monterey Formation, and the Obispo Formation. The area is tectonically active, located east of the active Hosgri Fault and in the southern limb of the northwest trending Pismo Syncline. Most of the potential tunnel for the neutrino detector lies within the Obispo Formation. Review of previous geologic studies, observations from a field visit, and selected physical and mechanical properties of rock samples collected from the site provided baseline geological information used in developing a preliminary estimate for tunneling construction cost. Gamma-ray spectrometric results indicate low levels of radioactivity for uranium, thorium, and potassium. Grain density, bulk density, and porosity values for these rock samples range from 2.37 to 2.86 g/cc, 1.41 to 2.57 g/cc, and 1.94 to 68.5 percent respectively. Point load, unconfined compressive strength, and ultrasonic velocity tests were conducted to determine rock

  8. Geologic Investigation of a Potential Site for a Next-Generation Reactor Neutrino Oscillation Experiment -- Diablo Canyon, San Luis Obispo County, CA

    Energy Technology Data Exchange (ETDEWEB)

    Onishi, Celia Tiemi; Dobson, Patrick; Nakagawa, Seiji; Glaser, Steven; Galic, Dom

    2004-08-01

    This report provides information on the geology and selected physical and mechanical properties of surface rocks collected at Diablo Canyon, San Luis Obispo County, California as part of the design and engineering studies towards a future reactor neutrino oscillation experiment. The main objective of this neutrino project is to study the process of neutrino flavor transformation--or neutrino oscillation--by measuring neutrinos produced in the fission reactions of a nuclear power plant. Diablo Canyon was selected as a candidate site because it allows the detectors to be situated underground in a tunnel close to the source of neutrinos (i.e., at a distance of several hundred meters from the nuclear power plant) while having suitable topography for shielding against cosmic rays. The detectors have to be located underground to minimize the cosmic ray-related background noise that can mimic the signal of reactor neutrino interactions in the detector. Three Pliocene-Miocene marine sedimentary units dominate the geology of Diablo Canyon: the Pismo Formation, the Monterey Formation, and the Obispo Formation. The area is tectonically active, located east of the active Hosgri Fault and in the southern limb of the northwest trending Pismo Syncline. Most of the potential tunnel for the neutrino detector lies within the Obispo Formation. Review of previous geologic studies, observations from a field visit, and selected physical and mechanical properties of rock samples collected from the site provided baseline geological information used in developing a preliminary estimate for tunneling construction cost. Gamma-ray spectrometric results indicate low levels of radioactivity for uranium, thorium, and potassium. Grain density, bulk density, and porosity values for these rock samples range from 2.37 to 2.86 g/cc, 1.41 to 2.57 g/cc, and 1.94 to 68.5% respectively. Point load, unconfined compressive strength, and ultrasonic velocity tests were conducted to determine rock mechanical

  9. Internal architecture of the proto-Kern Canyon Fault at Engineer's Point, Lake Isabella Dam site, Kern County, California

    Science.gov (United States)

    Martindale, Z. S.; Andrews, G. D.; Brown, S. R.; Krugh, W. C.

    2014-12-01

    The core of the Cretaceous (?) proto-Kern Canyon Fault (KCF) is exposed continuously for 1.25 km along Engineer's Point at Lake Isabella, Kern County, California. The proto-KCF is notable for (1) its long and complex history within, and perhaps preceding the Sierra Nevada batholith, and (2) hosting the Quaternary Kern Canyon Fault, an active fault that threatens the integrity of the Lake Isabella auxiliary dam and surrounding communities. We are investigating the internal architecture of the proto-KCF to explore its control on the likely behavior of the modern KCF. The proto-KCF is developed in the Alta Sierra biotite-granodiorite pluton. A traverse across Engineer's Point, perpendicular to the proto-KCF trace, reveals gradational increases in fracture density, fracture length, bulk alteration, and decreases in fracture spacing and grain size toward the fault core. Mapping of the fault core reveals two prominent and laterally extensive zones: (1) continuous foliated blastomylonitic granodiorite with steeply-dipping, anastomosing shear bands and minor mylonite planes, and (2) foliated orange and green fault breccia with intergranular gouge, strong C/S fabric, and a central gouge plane. The fault breccia zone is intruded by a lensoidal, post-deformation dacite dike, probably ca. 105 - 102 Ma (Nadin & Saleeby, 2008) and is weakly overprinted by a set of cross-cutting spaced, short, brittle fractures, often coated in calcite, which we infer to be genetically related to the modern KCF. We present our structural and lithological data that will be supported by mineralogical and geochemical analyses. E. Nadin & J. Saleeby (2008) Disruption of regional primary structure of the Sierra Nevada batholith by the Kern Canyon fault system, California: Geological Society of America Special Paper 438, p. 429-454.

  10. Ecotoxicological screen of Potential Release Site 50-006(d) of Operable Unit 1147 of Mortandad Canyon and relationship to the Radioactive Liquid Waste Treatment Facilities project

    International Nuclear Information System (INIS)

    Potential ecological risk associated with soil contaminants in Potential Release Site (PRS) 50-006(d) of Mortandad Canyon at the Los Alamos National Laboratory was assessed by performing an ecotoxicological risk screen. The PRS surrounds Outfall 051, which discharges treated effluent from the Radioactive Liquid Waste Treatment Facility. Discharge at the outfall is permitted under the Clean Water Act National Pollution Discharge Elimination System. Radionuclide discharge is regulated by US Department of Energy (DOE) Order 5400.5. Ecotoxicological Screening Action Levels (ESALSs) were computed for nonradionuclide constituents in the soil, and human risk SALs for radionuclides were used as ESALs. Within the PRS and beginning at Outfall 051, soil was sampled at three points along each of nine linear transects at 100-ft intervals. Soil samples from 3 depths for each sampling point were analyzed for the concentration of a total of 121 constituents. Only the results of the surface sampling are reported in this report

  11. Ecotoxicological screen of Potential Release Site 50-006(d) of Operable Unit 1147 of Mortandad Canyon and relationship to the Radioactive Liquid Waste Treatment Facilities project

    Energy Technology Data Exchange (ETDEWEB)

    Gonzales, G.J.; Newell, P.G.

    1996-04-01

    Potential ecological risk associated with soil contaminants in Potential Release Site (PRS) 50-006(d) of Mortandad Canyon at the Los Alamos National Laboratory was assessed by performing an ecotoxicological risk screen. The PRS surrounds Outfall 051, which discharges treated effluent from the Radioactive Liquid Waste Treatment Facility. Discharge at the outfall is permitted under the Clean Water Act National Pollution Discharge Elimination System. Radionuclide discharge is regulated by US Department of Energy (DOE) Order 5400.5. Ecotoxicological Screening Action Levels (ESALSs) were computed for nonradionuclide constituents in the soil, and human risk SALs for radionuclides were used as ESALs. Within the PRS and beginning at Outfall 051, soil was sampled at three points along each of nine linear transects at 100-ft intervals. Soil samples from 3 depths for each sampling point were analyzed for the concentration of a total of 121 constituents. Only the results of the surface sampling are reported in this report.

  12. ACCELERATED PILOT PROJECT FOR U CANYON DEMOLITION

    Energy Technology Data Exchange (ETDEWEB)

    KEHLER KL

    2011-01-13

    At the U.S. Department of Energy's Hanford Site in southeast Washington State, CH2M HILL Plateau Remediation Company (CH2M HILL) is underway on a first-of-a-kind project with the decommissioning and demolition of the U Canyon. Following the U.S. Environmental Protection Agency's Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) Record of Decision for the final remediation of the canyon, CH2M HILL is combining old and new technology and techniques to prepare U Canyon for demolition. The selected remedial action called first for consolidating and grouting equipment currently in the canyon into lower levels of the plant (openings called cells), after which the cell galleries, hot pipe trench, ventilation tunnel, drains and other voids below the operating deck and crane-way deck levels will be filled with approximately 20,000 cubic yards of grout and the canyon roof and walls demolished down to the approximate level of the canyon deck. The remaining canyon structure will then be buried beneath an engineered barrier designed to control potential contaminant migration for a 500-year life. Methods and lessons learned from this project will set the stage for the future demolition of Hanford's four other canyon-type processing facilities.

  13. Bering Sea surface water conditions during Marine Isotope Stages 12 to 10 at Navarin Canyon (IODP Site U1345)

    Science.gov (United States)

    Caissie, Beth E.; Brigham-Grette, Julie; Cook, Mea S.; Colmenero-Hidalgo, Elena

    2016-09-01

    Records of past warm periods are essential for understanding interglacial climate system dynamics. Marine Isotope Stage 11 occurred from 425 to 394 ka, when global ice volume was the lowest, sea level was the highest, and terrestrial temperatures were the warmest of the last 500 kyr. Because of its extreme character, this interval has been considered an analog for the next century of climate change. The Bering Sea is ideally situated to record how opening or closing of the Pacific-Arctic Ocean gateway (Bering Strait) impacted primary productivity, sea ice, and sediment transport in the past; however, little is known about this region prior to 125 ka. IODP Expedition 323 to the Bering Sea offered the unparalleled opportunity to look in detail at time periods older than had been previously retrieved using gravity and piston cores. Here we present a multi-proxy record for Marine Isotope Stages 12 to 10 from Site U1345, located near the continental shelf-slope break. MIS 11 is bracketed by highly productive laminated intervals that may have been triggered by flooding of the Beringian shelf. Although sea ice is reduced during the early MIS 11 laminations, it remains present at the site throughout both glacials and MIS 11. High summer insolation is associated with higher productivity but colder sea surface temperatures, which implies that productivity was likely driven by increased upwelling. Multiple examples of Pacific-Atlantic teleconnections are presented including laminations deposited at the end of MIS 11 in synchrony with millennial-scale expansions in sea ice in the Bering Sea and stadial events seen in the North Atlantic. When global eustatic sea level was at its peak, a series of anomalous conditions are seen at U1345. We examine whether this is evidence for a reversal of Bering Strait throughflow, an advance of Beringian tidewater glaciers, or a turbidite.

  14. Marble Canyon spring sampling investigation

    International Nuclear Information System (INIS)

    The Mississippian Leadville Limestone is the most permeable formation in the lower hydrostratigraphic unit underlying the salt beds of the Paradox Formation in Gibson Dome, Paradox Basin, Utah, which is being considered as a potential nuclear waste repository site. The closest downgradient outcrop of the Mississippian limestone is along the Colorado River in Marble Canyon, Arizona. This report describes the sampling and interpretation of springs in that area to assess the relative contribution of Gibson Dome-type Leadville Limestone ground water to that spring discharge. The high-volume (hundreds of liters per second or thousands of gallons per minute) springs discharging from fault zones in Marble Canyon are mixtures of water recharged west of the Colorado River on the Kaibab Plateau and east of the river in the Kaiparowits basin. No component of Gibson Dome-type Leadville Limestone ground water is evident in major and trace element chemistry or isotopic composition of the Marble Canyon Springs. A low-volume (0.3 liters per second or 5 gallons per minute) spring with some chemical and isotopic characteristics of Gibson Dome-type Leadville Limestone water diluted by Kaiparowits basin-type water issues from a travertine mound in the Bright Angel Shale on the Little Colorado River. However, the stable isotopic composition and bromide levels of that spring discharge, in addition to probable ground-water flow paths, contradict the dilution hypothesis

  15. Holocene sedimentary activity in a non-terrestrially coupled submarine canyon: Cook Strait Canyon system, New Zealand

    Science.gov (United States)

    Mountjoy, J. J.; Micallef, A.; Stevens, C. L.; Stirling, M. W.

    2014-06-01

    acceleration, ignoring the effect of the water column above the seabed) at this site is estimated to be 0.23g. Fresh rock outcrops and bed-scour in the lower canyon floor indicate that remobilised material is transported to the deep ocean. The processes identified here are likely to be analogous to those occurring in many non-coupled shelf-indenting canyons on active margins globally, and provide a framework within which the biological response to geomorphic processes in submarine canyons can be assessed.

  16. Bell Canyon test summary report

    International Nuclear Information System (INIS)

    The Bell Canyon Test was an in situ evaluation of the ability of a cement grout plug to seal boreholes. It consisted of a 2-m-long, 20-cm-diameter grout plug in an anhydrite formation at a depth of 1370 m, directly above an aquifer that provided a 12.4 MPa (1800 psi) differential pressure. The aquifer had a production capability of 38,000 l/day (240 bbl/day, 104 gal/day). The observed leakage after plug installation was 0.6 l/day, which is equivalent to a 50 microdarcy flow path assuming all flow occurred through the plug cross-sectional area. Laboratory results and analysis of field data indicate that the bulk of the flow occurred through a microstructure at the interface between the plug and the host rock. The Bell Canyon Test demonstrated that a plug could be formulated, emplaced, and tested under actual conditions and provide acceptable performance. When these results are related to the WIPP performance assessment models, they provide additional confidence that borehole plugging can be accomplished satisfactorily. The Bell Canyon results can also be used as basis for future activities in the generic repository sealing program for similar emplacements and performance assessment evaluations. If the observed leakage rates are not acceptable at other sites, the BCT results would indicate that the first step in improving such emplacements should deal with improved bonding of the plug to the rock at these sites. The results obtained from the BCT, when coupled with results from long-term durability assessments, form a plug performance data basis for repository designers at other proposed waste repository sites

  17. H-Canyon Recovery Crawler

    Energy Technology Data Exchange (ETDEWEB)

    Kriikku, E. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hera, K. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Marzolf, A. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Phillips, M. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-08-01

    The Nuclear Material Disposition Project group asked the Savannah River National Lab (SRNL) Research and Development Engineering (R&DE) department to help procure, test, and deploy a remote crawler to recover the 2014 Inspection Crawler (IC) that tipped over in the H-Canyon Air Exhaust Tunnel. R&DE wrote a Procurement Specification for a Recovery Crawler (RC) and SRNS Procurement Department awarded the contract to Power Equipment Manufacturing Inc. (PEM). The PEM RC was based on their standard sewer inspection crawler with custom arms and forks added to the front. The arms and forks would be used to upright the 2014 Inspection Crawler. PEM delivered the RC and associated cable reel, 2014 Inspection Crawler mockup, and manuals in late April 2015. R&DE and the team tested the crawler in May of 2015 and made modifications based on test results and Savannah River Site (SRS) requirements. R&DE delivered the RC to H-Area at the end of May. The team deployed the RC on June 9, 10, and 11, 2015 in the H-Canyon Air Exhaust Tunnel. The RC struggled with some obstacles in the tunnel, but eventually made it to the IC. The team spent approximately five hours working to upright the IC and eventually got it on its wheels. The IC travelled approximately 20 feet and struggled to drive over debris on the air tunnel floor. Unfortunately the IC tripped over trying to pass this obstacle. The team decided to leave the IC in this location and inspect the tunnel with the RC. The RC passed the IC and inspected the tunnel as it travelled toward H-Canyon. The team turned the RC around when it was about 20 feet from the H-Canyon crossover tunnel. From that point, the team drove the RC past the manway towards the new sand filter and stopped approximately 20 feet from the new sand filter. The team removed the RC from the tunnel, decontaminated the RC, and stored it the manway building, 294-2H. The RC deployment confirmed the IC was not in a condition to perform useful tunnel inspections and

  18. Environmental analysis of Lower Pueblo/Lower Los Alamos Canyon, Los Alamos, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ferenbaugh, R.W.; Buhl, T.E.; Stoker, A.K.; Becker, N.M.; Rodgers, J.C.; Hansen, W.R.

    1994-12-01

    The radiological survey of the former radioactive waste treatment plant site (TA-45), Acid Canyon, Pueblo Canyon, and Los Alamos Canyon found residual contamination at the site itself and in the channel and banks of Acid, Pueblo, and lower Los Alamos Canyons all the way to the Rio Grande. The largest reservoir of residual radioactivity is in lower Pueblo Canyon, which is on DOE property. However, residual radioactivity does not exceed proposed cleanup criteria in either lower Pueblo or lower Los Alamos Canyons. The three alternatives proposed are (1) to take no action, (2) to construct a sediment trap in lower Pueblo Canyon to prevent further transport of residual radioactivity onto San Ildefonso Indian Pueblo land, and (3) to clean the residual radioactivity from the canyon system. Alternative 2, to cleanup the canyon system, is rejected as a viable alternative. Thousands of truckloads of sediment would have to be removed and disposed of, and this effort is unwarranted by the low levels of contamination present. Residual radioactivity levels, under either present conditions or projected future conditions, will not result in significant radiation doses to persons exposed. Modeling efforts show that future transport activity will not result in any residual radioactivity concentrations higher than those already existing. Thus, although construction of a sediment trap in lower Pueblo Canyon is a viable alternative, this effort also is unwarranted, and the no-action alternative is the preferred alternative.

  19. Environmental analysis of Lower Pueblo/Lower Los Alamos Canyon, Los Alamos, New Mexico

    International Nuclear Information System (INIS)

    The radiological survey of the former radioactive waste treatment plant site (TA-45), Acid Canyon, Pueblo Canyon, and Los Alamos Canyon found residual contamination at the site itself and in the channel and banks of Acid, Pueblo, and lower Los Alamos Canyons all the way to the Rio Grande. The largest reservoir of residual radioactivity is in lower Pueblo Canyon, which is on DOE property. However, residual radioactivity does not exceed proposed cleanup criteria in either lower Pueblo or lower Los Alamos Canyons. The three alternatives proposed are (1) to take no action, (2) to construct a sediment trap in lower Pueblo Canyon to prevent further transport of residual radioactivity onto San Ildefonso Indian Pueblo land, and (3) to clean the residual radioactivity from the canyon system. Alternative 2, to cleanup the canyon system, is rejected as a viable alternative. Thousands of truckloads of sediment would have to be removed and disposed of, and this effort is unwarranted by the low levels of contamination present. Residual radioactivity levels, under either present conditions or projected future conditions, will not result in significant radiation doses to persons exposed. Modeling efforts show that future transport activity will not result in any residual radioactivity concentrations higher than those already existing. Thus, although construction of a sediment trap in lower Pueblo Canyon is a viable alternative, this effort also is unwarranted, and the no-action alternative is the preferred alternative

  20. 2008 High-Flow Experiment at Glen Canyon Dam Benefits Colorado River Resources in Grand Canyon National Park

    Science.gov (United States)

    Melis, Theodore S.; Topping, David J.; Grams, Paul E.; Rubin, David M.; Wright, Scott A.; Draut, Amy E.; Hazel, Joseph E., Jr.; Ralston, Barbara E.; Kennedy, Theodore A.; Rosi-Marshall, Emma; Korman, Josh; Hilwig, Kara D.; Schmit, Lara M.

    2010-01-01

    On March 5, 2008, the Department of the Interior began a 60-hour high-flow experiment at Glen Canyon Dam, Arizona, to determine if water releases designed to mimic natural seasonal flooding could be used to improve downstream resources in Glen Canyon National Recreation Area and Grand Canyon National Park. U.S. Geological Survey (USGS) scientists and their cooperators undertook a wide range of physical and biological resource monitoring and research activities before, during, and after the release. Scientists sought to determine whether or not high flows could be used to rebuild Grand Canyon sandbars, create nearshore habitat for the endangered humpback chub, and benefit other resources such as archaeological sites, rainbow trout, aquatic food availability, and riverside vegetation. This fact sheet summarizes research completed by January 2010.

  1. The Whittard Canyon - A case study of submarine canyon processes

    Science.gov (United States)

    Amaro, T.; Huvenne, V. A. I.; Allcock, A. L.; Aslam, T.; Davies, J. S.; Danovaro, R.; De Stigter, H. C.; Duineveld, G. C. A.; Gambi, C.; Gooday, A. J.; Gunton, L. M.; Hall, R.; Howell, K. L.; Ingels, J.; Kiriakoulakis, K.; Kershaw, C. E.; Lavaleye, M. S. S.; Robert, K.; Stewart, H.; Van Rooij, D.; White, M.; Wilson, A. M.

    2016-08-01

    Submarine canyons are large geomorphological features that incise continental shelves and slopes around the world. They are often suggested to be biodiversity and biomass hotspots, although there is no consensus about this in the literature. Nevertheless, many canyons do host diverse faunal communities but owing to our lack of understanding of the processes shaping and driving this diversity, appropriate management strategies have yet to be developed. Here, we integrate all the current knowledge of one single system, the Whittard Canyon (Celtic Margin, NE Atlantic), including the latest research on its geology, sedimentology, geomorphology, oceanography, ecology, and biodiversity in order to address this issue. The Whittard Canyon is an active system in terms of sediment transport. The net suspended sediment transport is mainly up-canyon causing sedimentary overflow in some upper canyon areas. Occasionally sediment gravity flow events do occur, some possibly the result of anthropogenic activity. However, the role of these intermittent gravity flows in transferring labile organic matter to the deeper regions of the canyon appears to be limited. More likely, any labile organic matter flushed downslope in this way becomes strongly diluted with bulk material and is therefore of little food value for benthic fauna. Instead, the fresh organic matter found in the Whittard Channel mainly arrives through vertical deposition and lateral transport of phytoplankton blooms that occur in the area during spring and summer. The response of the Whittard Canyon fauna to these processes is different in different groups. Foraminiferal abundances are higher in the upper parts of the canyon and on the slope than in the lower canyon. Meiofaunal abundances in the upper and middle part of the canyon are higher than on adjacent slopes, but lower in the deepest part. Mega- and macrofauna abundances are higher in the canyon compared with the adjacent slope and are higher in the eastern than

  2. Downward and suspended sediment fluxes in the Palamós submarine canyon (North-Western Mediterranean)

    Science.gov (United States)

    Palanques, A.; Martín, J.; Puig, P.; Guillén, J.

    2003-04-01

    The Palamós canyon is deeply incised in the Northern Catatonia continental shelf (North-western Mediterranean) which favour an active shelf-slope sediment transfer. To study particle dynamics in this canyon, seven moorings arrays equipped with current meters, turbidimeters and sediment traps were deployed near the bottom along the main canyon axis (400, 1200 and 1700 m depth), on both canyon walls (1200 m depth) and on the adjacent slope (1200 m depth). One set of these instruments was also deployed at intermediate waters (400 m water depth) in the canyon axis. At surface and mid-depths, suspended sediment fluxes were oriented along the mean flow direction (NE-SW), whereas near-bottom sediment fluxes were more constrained by the local bathymetry. The higher near-bottom downward and suspended particle fluxes were not recorded in the canyon head but in the mid-canyon axis, suggesting additional sediment supplies through or over the canyon walls and/or sediment resuspension in the mid canyon region. Several events of sharp sediment flux increases took place in the mid-canyon axis site during the water stratification season. These events could be related to the action of internal waves and even to fishing activities. In the canyon walls, downward and suspended particle fluxes were higher in the southern wall, where currents were lower than in the northern wall, evidencing an asymmetrical pattern. In the adjacent slope sediment fluxes were significantly lower than in the canyon. An important increase of downward particle fluxes in the canyon axis and both walls occurred by mid-November when a severe storm took place. The pattern of the sediment fluxes in the Palamós Canyon has some differences in relation to those observed in other Mediterranean submarine canyons and has downward particle fluxes from 2 to10 times higher than other studied canyons of this region.

  3. Chromosomal organization of simple sequence repeats in the Pacific oyster (Crassostrea gigas): (GGAT)4, (GT)7 and (TA)10 chromosome patterns

    Indian Academy of Sciences (India)

    K. Bouilly; R. Chaves; A. Leitão; A. Benabdelmouna; H. Guedes-Pinto

    2008-08-01

    Chromosome identification is essential in oyster genomic research. Fluorescence in situ hybridization (FISH) offers new opportunities for the identification of oyster chromosomes. It has been used to locate satellite DNAs, telomeres or ribosomal DNA sequences. However, regarding chromosome identification, no study has been conducted with simple sequence repeats (SSRs). FISH was used to probe the physical organization of three particular SSRs, (GGAT)4, (GT)7 and (TA)10 onto metaphase chromosomes of the Pacific oyster, Crassostrea gigas. Hybridization signals were observed in all the SSR probes, but the distribution and intensity of signals varied according to the oligonucleotide repeat. The intercalary, centromeric and telomeric bands were observed along the chromosomes, and for each particular repeat every chromosome pair presented a similar pattern, allowing karyotypic analysis with all the SSRs tested. Our study is the first in mollusks to show the application of SSR in situ hybridization for chromosome identification and karyotyping. This technique can be a useful tool for oyster comparative studies and to understand genome organization in different oyster taxa.

  4. H CANYON PROCESSING IN CORRELATION WITH FH ANALYTICAL LABS

    Energy Technology Data Exchange (ETDEWEB)

    Weinheimer, E.

    2012-08-06

    Management of radioactive chemical waste can be a complicated business. H Canyon and F/H Analytical Labs are two facilities present at the Savannah River Site in Aiken, SC that are at the forefront. In fact H Canyon is the only large-scale radiochemical processing facility in the United States and this processing is only enhanced by the aid given from F/H Analytical Labs. As H Canyon processes incoming materials, F/H Labs provide support through a variety of chemical analyses. Necessary checks of the chemical makeup, processing, and accountability of the samples taken from H Canyon process tanks are performed at the labs along with further checks on waste leaving the canyon after processing. Used nuclear material taken in by the canyon is actually not waste. Only a small portion of the radioactive material itself is actually consumed in nuclear reactors. As a result various radioactive elements such as Uranium, Plutonium and Neptunium are commonly found in waste and may be useful to recover. Specific processing is needed to allow for separation of these products from the waste. This is H Canyon's specialty. Furthermore, H Canyon has the capacity to initiate the process for weapons-grade nuclear material to be converted into nuclear fuel. This is one of the main campaigns being set up for the fall of 2012. Once usable material is separated and purified of impurities such as fission products, it can be converted to an oxide and ultimately turned into commercial fuel. The processing of weapons-grade material for commercial fuel is important in the necessary disposition of plutonium. Another processing campaign to start in the fall in H Canyon involves the reprocessing of used nuclear fuel for disposal in improved containment units. The importance of this campaign involves the proper disposal of nuclear waste in order to ensure the safety and well-being of future generations and the environment. As processing proceeds in the fall, H Canyon will have a substantial

  5. 78 FR 123 - Diablo Canyon, Independent Spent Fuel Storage Installation; License Amendment Request...

    Science.gov (United States)

    2013-01-02

    ... COMMISSION Diablo Canyon, Independent Spent Fuel Storage Installation; License Amendment Request, Opportunity... Spent Fuel Storage and Transportation, Office of Nuclear Material Safety and Safeguards, U.S. Nuclear... Canyon Independent Spent Fuel Storage Installation (ISFSI) site located in San Luis Obispo...

  6. The marine soundscape of the Perth Canyon

    Science.gov (United States)

    Erbe, Christine; Verma, Arti; McCauley, Robert; Gavrilov, Alexander; Parnum, Iain

    2015-09-01

    The Perth Canyon is a submarine canyon off Rottnest Island in Western Australia. It is rich in biodiversity in general, and important as a feeding and resting ground for great whales on migration. Australia's Integrated Marine Observing System (IMOS) has moorings in the Perth Canyon monitoring its acoustical, physical and biological oceanography. Data from these moorings, as well as weather data from a near-by Bureau of Meteorology weather station on Rottnest Island and ship traffic data from the Australian Maritime Safety Authority were correlated to characterise and quantify the marine soundscape between 5 and 3000 Hz, consisting of its geophony, biophony and anthrophony. Overall, biological sources are a strong contributor to the soundscape at the IMOS site, with whales dominating seasonally at low (15-100 Hz) and mid frequencies (200-400 Hz), and fish or invertebrate choruses dominating at high frequencies (1800-2500 Hz) at night time throughout the year. Ships contribute significantly to the 8-100 Hz band at all times of the day, all year round, albeit for a few hours at a time only. Wind-dependent noise is significant at 200-3000 Hz; winter rains are audible underwater at 2000-3000 Hz. We discuss how passive acoustic data can be used as a proxy for ocean weather. Passive acoustics is an efficient way of monitoring animal visitation times and relative densities, and potential anthropogenic influences.

  7. 2010 Pacific Gas and Electric Diablo Canyon Power Plant (DCPP): Diablo Canyon, CA Central Coast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Diablo Canyon Power Plant (DCPP) LiDAR and Imagery datasets are comprised of three separate LiDAR surveys: Diablo Canyon (2010), Diablo Canyon (2010), and San...

  8. Small Mammal Sampling in Mortandad and Los Alamos Canyons, 2005

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, Kathy; Sherwood, Sherri; Robinson, Rhonda

    2006-08-15

    As part of an ongoing ecological field investigation at Los Alamos National Laboratory, a study was conducted that compared measured contaminant concentrations in sediment to population parameters for small mammals in the Mortandad Canyon watershed. Mortandad Canyon and its tributary canyons have received contaminants from multiple solid waste management units and areas of concern since establishment of the Laboratory in the 1940s. The study included three reaches within Effluent and Mortandad canyons (E-1W, M-2W, and M-3) that had a spread in the concentrations of metals and radionuclides and included locations where polychlorinated biphenyls and perchlorate had been detected. A reference location, reach LA-BKG in upper Los Alamos Canyon, was also included in the study for comparison purposes. A small mammal study was initiated to assess whether potential adverse effects were evident in Mortandad Canyon due to the presence of contaminants, designated as contaminants of potential ecological concern, in the terrestrial media. Study sites, including the reference site, were sampled in late July/early August. Species diversity and the mean daily capture rate were the highest for E-1W reach and the lowest for the reference site. Species composition among the three reaches in Mortandad was similar with very little overlap with the reference canyon. Differences in species composition and diversity were most likely due to differences in habitat. Sex ratios, body weights, and reproductive status of small mammals were also evaluated. However, small sample sizes of some species within some sites affected the analysis. Ratios of males to females by species of each site (n = 5) were tested using a Chi-square analysis. No differences were detected. Where there was sufficient sample size, body weights of adult small mammals were compared between sites. No differences in body weights were found. Reproductive status of species appears to be similar across sites. However, sample

  9. Small Mammal Sampling in Mortandad and Los Alamos Canyons, 2005

    International Nuclear Information System (INIS)

    As part of an ongoing ecological field investigation at Los Alamos National Laboratory, a study was conducted that compared measured contaminant concentrations in sediment to population parameters for small mammals in the Mortandad Canyon watershed. Mortandad Canyon and its tributary canyons have received contaminants from multiple solid waste management units and areas of concern since establishment of the Laboratory in the 1940s. The study included three reaches within Effluent and Mortandad canyons (E-1W, M-2W, and M-3) that had a spread in the concentrations of metals and radionuclides and included locations where polychlorinated biphenyls and perchlorate had been detected. A reference location, reach LA-BKG in upper Los Alamos Canyon, was also included in the study for comparison purposes. A small mammal study was initiated to assess whether potential adverse effects were evident in Mortandad Canyon due to the presence of contaminants, designated as contaminants of potential ecological concern, in the terrestrial media. Study sites, including the reference site, were sampled in late July/early August. Species diversity and the mean daily capture rate were the highest for E-1W reach and the lowest for the reference site. Species composition among the three reaches in Mortandad was similar with very little overlap with the reference canyon. Differences in species composition and diversity were most likely due to differences in habitat. Sex ratios, body weights, and reproductive status of small mammals were also evaluated. However, small sample sizes of some species within some sites affected the analysis. Ratios of males to females by species of each site (n = 5) were tested using a Chi-square analysis. No differences were detected. Where there was sufficient sample size, body weights of adult small mammals were compared between sites. No differences in body weights were found. Reproductive status of species appears to be similar across sites. However, sample

  10. Biological and physical processes in and around Astoria submarine Canyon, Oregon, USA

    Science.gov (United States)

    Bosley, Keith L.; Lavelle, J. William; Brodeur, Richard D.; Wakefield, W. Waldo; Emmett, Robert L.; Baker, Edward T.; Rehmke, Kara M.

    2004-09-01

    Astoria Canyon represents the westernmost portion of the Columbia River drainage system, with the head of the canyon beginning just 16 km west of the mouth of the Columbia River along the northern Oregon and southern Washington coasts. During the summer of 2001, physical, chemical, and biological measurements in the canyon were taken to better understand the hydrodynamic setting of, and the feeding relationships among, the pelagic and benthic communities. Results show that currents were strongly tidal, and transport, where measured, was primarily up and into the canyon below shelf depth as previous studies in the canyon have shown. Temperature time series suggests that the largest diurnal oscillations occurred at, or were trapped near, the bottom of the canyon. Within the upper canyon, subtidal temperature was correlated with upper-level shelf-edge currents, linking subtidal upwelling events in the canyon with near-surface subtidal along-shore flow. Invertebrates, such as shrimp, euphausiids, and squid, as well as mesopelagic fishes, dominated the Isaacs-Kidd midwater trawl catches along the canyon walls. Large trawl catches were comprised mainly of hake and rockfishes (shallow trawls) and macrourids, scorpaenids, stomiids, and zoarcids (bottom trawls). Gut-content analysis of rockfishes and lanternfishes revealed substantial use of midwater prey such as euphausiids and mesopelagic fishes. The δ13C values of fishes and invertebrates reflected local primary production, as indicated by particulate organic matter (POM) δ13C values from samples collected at various depths along the axis of the canyon, as well as across the canyon at several sites. The δ15N values of fishes and invertebrates indicated lanternfishes, along with euphausiids, amphipods, shrimp and squid, may be important dietary components of higher-trophic-level fishes in both the benthic and benthopelagic food webs. The δ13C and δ15N values of Sebastes species showed significant enrichment in the

  11. Deepwater Canyons 2013: Pathways to the Abyss

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Leg I focused on biological objectives in Norfolk Canyon, with some sampling in Baltimore Canyon. Leg II focused on archaeological targets in and around the Norfolk...

  12. Movements of subadult prickly sharks Echinorhinus cookei in the Monterey Canyon

    OpenAIRE

    Starr, Richard M.

    2009-01-01

    The prickly shark Echinorhinus cookei is a poorly known predatory shark that occurs in the Monterey Canyon, USA. Between March 2005 and September 2006, 15 subadult prickly sharks (170 to 270 cm total length) were tagged with acoustic transmitters and tracked to determine their site fidelity, home range, habitat use, rates of movement, and diel activity. An array of moored receivers extending 3.5 km offshore from the apex of the Monterey Canyon recorded the occurrence of 8 sharks tagged with c...

  13. SYCAMORE CANYON PRIMITIVE AREA, ARIZONA.

    Science.gov (United States)

    Huff, Lyman C.; Raabe, R.C.

    1984-01-01

    The Sycamore Canyon Primitive Area, which occupies about 74 sq mi, lies about 24 mi southwest of Flagstaff, Arizona. To help evaluate the area for mineral resources, sediment samples were collected along Sycamore Creek and its tributaries. These were analyzed for traces of the ore metals without finding any local concentrations. In addition, a scintillometer was used to test rocks in the area without finding any abnormal radioactivity.

  14. UV Radiation in an Urban Canyon in Southeast Queensland

    Science.gov (United States)

    McKinley, A. R.; Moore, M. R.; Kimlin, M. G.

    2006-12-01

    Ultraviolet radiation (UV) has the possibility to both harm and to benefit human beings when unprotected exposure occurs. After receiving small amounts of UV our bodies begin to synthesise vitamin D, which is essential for maintaining healthy bones, however excessive UV exposure can result in a variety of damaging outcomes ranging from sunburn to skin cancer and cataracts. For this reason it is very important to understand the different environments in which people encounter UV so as to better prepare the public to make smart and healthy sun exposure decisions. Each day more and more people are moving into large cities around the world and spending their time inside the urban canyon, however UV measurements are generally taken at scientific stations in open areas or on top of tall buildings, meaning that at times the environmental characteristics measured may not accurately represent those found at street-level in these highly urbanized areas. Urban canyons are home to both very tall buildings and tropospheric air pollution, each of which reduces the amount of UV reaching street-level. This study measured the varying difference between UV measurements taken at street-level and at a standard UV monitoring site on top of a building outside of the urban canyon. Investigation was conducted in the central business district (CBD) of Brisbane, Australia, which models the CBDs of large cities around the world in that it boasts a great number of tall buildings, including many skyscrapers. Data was collected under clear sky conditions at five different street-level sites in the CBD (on either side of two streets running perpendicular to one another (four sites) and in a public square) and then compared to that obtained on the same day at the Queensland University of Technology's Australian Sun and Health Research Laboratory (ASHRL), which is located 2.5 kilometres outside Brisbane's CBD. Minimum erythemal dose (MED) data was collected at each location and it was found that

  15. Electrical resistance sensors record spring flow timing, Grand Canyon, Arizona

    Science.gov (United States)

    Adams, E.A.; Monroe, S.A.; Springer, A.E.; Blasch, K.W.; Bills, D.J.

    2006-01-01

    Springs along the south rim of the Grand Canyon, Arizona, are important ecological and cultural resources in Grand Canyon National Park and are discharge points for regional and local aquifers of the Coconino Plateau. This study evaluated the applicability of electrical resistance (ER) sensors for measuring diffuse, low-stage (flow in the steep, rocky spring-fed tributaries of the south rim. ER sensors were used to conduct a baseline survey of spring flow timing at eight sites in three spring-fed tributaries in Grand Canyon. Sensors were attached to a nearly vertical rock wall at a spring outlet and were installed in alluvial and bedrock channels. Spring flow timing data inferred by the ER sensors were consistent with observations during site visits, with flow events recorded with collocated streamflow gauging stations and with local precipitation gauges. ER sensors were able to distinguish the presence of flow along nearly vertical rock surfaces with flow depths between 0.3 and 1.0 cm. Laboratory experiments confirmed the ability of the sensors to monitor the timing of diffuse flow on impervious surfaces. A comparison of flow patterns along the stream reaches and at springs identified the timing and location of perennial and intermittent flow, and periods of increased evapotranspiration.

  16. Primary Initiation of Submarine Canyons

    CERN Document Server

    Herndon, J Marvin

    2011-01-01

    The discovery of close-to-star gas-giant exo-planets lends support to the idea of Earth's origin as a Jupiter-like gas-giant and to the consequences of its compression, including whole-Earth decompression dynamics that gives rise, without requiring mantle convection, to the myriad measurements and observations whose descriptions are attributed to plate tectonics. I propose here another, unanticipated consequence of whole-Earth decompression dynamics: namely, a specific, dominant, non-erosion, underlying initiation-mechanism precursor for submarine canyons that follows as a direct consequence of Earth's early origin as a Jupiter-like gas-giant.

  17. An experimental approach to submarine canyon evolution

    Science.gov (United States)

    Lai, Steven Y. J.; Gerber, Thomas P.; Amblas, David

    2016-03-01

    We present results from a sandbox experiment designed to investigate how sediment gravity flows form and shape submarine canyons. In the experiment, unconfined saline gravity flows were released onto an inclined sand bed bounded on the downstream end by a movable floor that was used to increase relief during the experiment. In areas unaffected by the flows, we observed featureless, angle-of-repose submarine slopes formed by retrogressive breaching processes. In contrast, areas influenced by gravity flows cascading across the shelf break were deeply incised by submarine canyons with well-developed channel networks. Normalized canyon long profiles extracted from successive high-resolution digital elevation models collapse to a single profile when referenced to the migrating shelf-slope break, indicating self-similar growth in the relief defined by the canyon and intercanyon profiles. Although our experimental approach is simple, the resulting canyon morphology and behavior appear similar in several important respects to that observed in the field.

  18. Prehistoric deforestation at Chaco Canyon?

    Science.gov (United States)

    Wills, W H; Drake, Brandon L; Dorshow, Wetherbee B

    2014-08-12

    Ancient societies are often used to illustrate the potential problems stemming from unsustainable land-use practices because the past seems rife with examples of sociopolitical "collapse" associated with the exhaustion of finite resources. Just as frequently, and typically in response to such presentations, archaeologists and other specialists caution against seeking simple cause-and effect-relationships in the complex data that comprise the archaeological record. In this study we examine the famous case of Chaco Canyon, New Mexico, during the Bonito Phase (ca. AD 860-1140), which has become a prominent popular illustration of ecological and social catastrophe attributed to deforestation. We conclude that there is no substantive evidence for deforestation at Chaco and no obvious indications that the depopulation of the canyon in the 13th century was caused by any specific cultural practices or natural events. Clearly there was a reason why these farming people eventually moved elsewhere, but the archaeological record has not yet produced compelling empirical evidence for what that reason might have been. Until such evidence appears, the legacy of Ancestral Pueblo society in Chaco should not be used as a cautionary story about socioeconomic failures in the modern world.

  19. Davis Canyon noise analysis: Revision 2

    International Nuclear Information System (INIS)

    A study was performed as part of the Civilian Radioactive Waste Management Program to quantify the level and effect of noise from the various major phases of development of the proposed potentially acceptable nuclear waste repository site at Davis Canyon, Utah. This report contains the results of a predictive noise level study for the site characterization, repository construction, and repository operational phases. Included herein are graphic representations of energy averaged sound levels, and of audibility levels representing impact zones expected during each phase. Sound levels from onsite and offsite activity including traffic on highways and railroad routes are presented in isopleth maps. A description of the Environmental Noise Prediction Model used for the study, the study basis and methodologies, and actual modeling data are provided. Noise and vibration levels from blasting are also predicted and evaluated. Protective noise criteria containing a margin of safety are used in relation to residences, schools, churches, noise-sensitive recreation areas, and noise-sensitive biological resources. Protective ground motion criteria for ruins and delicate rock formation in Canyonlands National Park and for human annoyance are used in the evaluation of blasting. The evaluations provide the basis for assessing the noise impacts from the related activities at the proposed repository. 45 refs., 21 figs., 15 tabs

  20. Litter in submarine canyons off the west coast of Portugal

    Science.gov (United States)

    Mordecai, Gideon; Tyler, Paul A.; Masson, Douglas G.; Huvenne, Veerle A. I.

    2011-12-01

    Marine litter is of global concern and is present in all the world's oceans, including deep benthic habitats where the extent of the problem is still largely unknown. Litter abundance and composition were investigated using video footage and still images from 16 Remotely Operated Vehicle (ROV) dives in Lisbon, Setúbal, Cascais and Nazaré Canyons located west of Portugal. Litter was most abundant at sites closest to the coastline and population centres, suggesting the majority of the litter was land sourced. Plastic was the dominant type of debris, followed by fishing gear. Standardised mean abundance was 1100 litter items km -2, but was as high as 6600 litter items km -2 in canyons close to Lisbon. Although all anthropogenic material may be harmful to biota, debris was also used as a habitat by some macro-invertebrates. Litter composition and abundance observed in the canyons of the Portuguese margin were comparable to those seen in other deep sea areas around the world. Accumulation of litter in the deep sea is a consequence of human activities both on land and at sea. This needs to be taken into account in future policy decisions regarding marine pollution.

  1. Internal waves in the Petacalco canyon, Mexico

    Science.gov (United States)

    Ruiz-Angulo, Angel; Zavala-Hidalgo, Jorge

    2012-11-01

    On the Mexican coastline, specifically on the Pacific side, there are many submarine canyons. One of the key rolls of coastal submarine canyons is that deep water from adjacent oceanic regions is brought up to the shelf with lots of nutrients enhancing primary production. The head of the Petacalco canyon is located in the Petacalco Bay, in the Pacific Ocean (ca. 17.5N and 102W). During, previous CTD surveys in the area, strong upwelling has been noticed, based on those observations a later survey was designed covering the Petacalco canyon with much larger spatial resolution. Along with those measurements, two thermistor arrays were deployed on the SW crest of the canyon at depths of approximately 60 [m]. The observations, from the thermistor arrays, show large temporal temperature variations with a semi-diurnal frequency. Those variations suggest the presence of internal waves traveling along the canyon axis, if the incidence angle of the internal wave matches the topographic slope results on breaking of internal waves enhancing mixing. This condition occurs at several locations along the canyon axis producing enough mixing of deep oceanic waters with continental waters, increasing the abundance of nutrients in the surrounding region.

  2. Flow dynamics around downwelling submarine canyons

    Directory of Open Access Journals (Sweden)

    J. M. Spurgin

    2014-05-01

    Full Text Available Flow dynamics around a downwelling submarine canyon were analysed with the Massachusetts Institute of Technology general circulation model. Blanes Canyon (Northwest Mediterranean was used for topographic and initial forcing conditions. Fourteen scenarios were modelled with varying forcing conditions. Rossby number and Burger number were used to determine the significance of Coriolis acceleration and stratification (respectively and their impacts on flow dynamics. A new non-dimensional parameter (χ was introduced to determine the significance of vertical variations in stratification. Some simulations do see brief periods of upwards displacement of water during the 10 day model period, however, the presence of the submarine canyon is found to enhance downwards advection of density in all model scenarios. High Burger numbers lead to negative vorticity and a trapped anticyclonic eddy within the canyon, as well as an increased density anomaly. Low Burger numbers lead to positive vorticity, cyclonic circulation and weaker density anomalies. Vertical variations in stratification affect zonal jet placement. Under the same forcing conditions, the zonal jet is pushed offshore in more uniformly stratified domains. Offshore jet location generates upwards density advection away from the canyon, while onshore jets generate downwards density advection everywhere within the model domain. Increasing Rossby values across the canyon axis, as well as decreasing Burger values, increase negative vertical flux at shelf break depth (150 m. Increasing Rossby numbers lead to stronger downwards advection of a passive tracer (nitrate as well as stronger vorticity within the canyon. Results from previous studies were explained within this new dynamic framework.

  3. Flow dynamics around downwelling submarine canyons

    Directory of Open Access Journals (Sweden)

    J. M. Spurgin

    2014-10-01

    Full Text Available Flow dynamics around a downwelling submarine canyon were analysed with the Massachusetts Institute of Technology general circulation model. Blanes Canyon (northwestern Mediterranean was used for topographic and initial forcing conditions. Fourteen scenarios were modelled with varying forcing conditions. Rossby and Burger numbers were used to determine the significance of Coriolis acceleration and stratification (respectively and their impacts on flow dynamics. A new non-dimensional parameter (χ was introduced to determine the significance of vertical variations in stratification. Some simulations do see brief periods of upwards displacement of water during the 10-day model period; however, the presence of the submarine canyon is found to enhance downwards advection of density in all model scenarios. High Burger numbers lead to negative vorticity and a trapped anticyclonic eddy within the canyon, as well as an increased density anomaly. Low Burger numbers lead to positive vorticity, cyclonic circulation, and weaker density anomalies. Vertical variations in stratification affect zonal jet placement. Under the same forcing conditions, the zonal jet is pushed offshore in more uniformly stratified domains. The offshore jet location generates upwards density advection away from the canyon, while onshore jets generate downwards density advection everywhere within the model domain. Increasing Rossby values across the canyon axis, as well as decreasing Burger values, increase negative vertical flux at shelf break depth (150 m. Increasing Rossby numbers lead to stronger downwards advection of a passive tracer (nitrate, as well as stronger vorticity within the canyon. Results from previous studies are explained within this new dynamic framework.

  4. Contours--Monterey Canyon and Vicinity, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents bathymetric contours for several seafloor maps of the Monterey Canyon and Vicinity map area, California. The raster data file is...

  5. Street canyon ventilation and atmospheric turbulence

    Science.gov (United States)

    Salizzoni, P.; Soulhac, L.; Mejean, P.

    Operational models for pollutant dispersion in urban areas require an estimate of the turbulent transfer between the street canyons and the overlying atmospheric flow. To date, the mechanisms that govern this process remain poorly understood. We have studied the mass exchange between a street canyon and the atmospheric flow above it by means of wind tunnel experiments. Fluid velocities were measured with a Particle Image Velocimetry system and passive scalar concentrations were measured using a Flame Ionisation Detector. The mass-transfer velocity between the canyon and the external flow has been estimated by measuring the cavity wash-out time. A two-box model, used to estimate the transfer velocity for varying dynamical conditions of the external flow, has been used to interpret the experimental data. This study sheds new light on the mechanisms which drive the ventilation of a street canyon and illustrates the influence of the external turbulence on the transfer process.

  6. Modelling Aerosol Dispersion in Urban Street Canyons

    Science.gov (United States)

    Tay, B. K.; Jones, D. P.; Gallagher, M. W.; McFiggans, G. B.; Watkins, A. P.

    2009-04-01

    Flow patterns within an urban street canyon are influenced by various micrometeorological factors. It also represents an environment where pollutants such as aerosols accumulate to high levels due to high volumes of traffic. As adverse health effects are being attributed to exposure to aerosols, an investigation of the dispersion of aerosols within such environments is of growing importance. In particular, one is concerned with the vertical structure of the aerosol concentration, the ventilation characteristics of the street canyon and the influence of aerosol microphysical processes. Due to the inherent heterogeneity of the aerosol concentrations within the street canyon and the lack of spatial resolution of measurement campaigns, these issues are an on-going debate. Therefore, a modelling tool is required to represent aerosol dispersion patterns to provide insights to results of past measurement campaigns. Computational Fluid Dynamics (CFD) models are able to predict detailed airflow patterns within urban geometries. This capability may be further extended to include aerosol dispersion, by an Euler-Euler multiphase approach. To facilitate the investigation, a two-dimensional, multiphase CFD tool coupled with the k-epsilon turbulence model and with the capability of modelling mixed convection flow regimes arising from both wind driven flows and buoyancy effects from heated walls was developed. Assuming wind blowing perpendicularly to the canyon axis and treating aerosols as a passive scalar, an attempt will be made to assess the sensitivities of aerosol vertical structure and ventilation characteristics to the various flow conditions. Numerical studies were performed using an idealized 10m by 10m canyon to represent a regular canyon and 10m by 5m to represent a deep one. An aerosol emission source was assigned on the centerline of the canyon to represent exhaust emissions. The vertical structure of the aerosols would inform future directives regarding the

  7. Habitat--Monterey Canyon and Vicinity, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the habitat map of the seafloor of the Monterey Canyon and Vicinity map area, California. The vector data file is included in...

  8. Marble Canyon 10 x 20 NTMS area Arizona: data report

    International Nuclear Information System (INIS)

    Results of ground water and stream/surface sediment reconnaissance (HSSR) in the National Topographic Map Series (NTMS) Marble Canyon 10 x 20 quadrangle are presented. The target sampling density for all media collected was one site per 12 square kilometers. This resulted in 884 sediment samples being collected; however, dry conditions and sparse population resulted in the collection of only 2 ground water samples. Grand Canyon National Park, Glen Canyon National Recreation Area, and much Indian tribal land in the southern half of the quadrangle were not sampled. Neutron activation analysis (NAA) results are given for uranium and 16 other elements in sediments, and for uranium and 9 other elements in ground water. Mass spectrometry results are given for helium in ground water. Field measurements for sediment samples are presented in tables and maps. Statistical summaries of data and a brief description of results are given. A generalized geologic map and a summary of the geology of the area are included. Data from ground water include: water chemistry measurements (pH, conductivity, and alkalinity); physical measurements (water temperature, and scintillometer readings); and elemental analyses (U, Al, Br, Cl, Dy, F, He, Mg, Mn, Na, and V). Data from sediment sites include: water chemistry measurements (where available) for pH, conductivity, and alkalinity; and elemental analyses(U, Th, Hf, Al, Ce, Dy, Eu, Fe, La, Lu, Mn, Sc, Sm, Na, Ti, V, and Yb). Sample site descriptors (stream characteristics, vegetation, etc.) are also tabulated. Histograms, cumulative frequency, and areal distribution plots for most elements; Log U/Th, Log U/Hf, and Log U/(Th + Hf) ratios; and scintillometer readings are included

  9. High-Resolution Multibeam, Sidescan, and Subbottom Surveys in and Around Monterey Canyon Using the MBARI Mapping AUV

    Science.gov (United States)

    Caress, D. W.; Thomas, H.; McEwen, R.; Henthorn, R.; Kirkwood, W. J.; Thompson, D.; Paull, C. K.; McGill, P.

    2005-12-01

    During 2004 and 2005, MBARI has conducted several high-resolution bathymetry, sidescan, and subbottom profiler surveys in and around Monterey Canyon, Monterey Bay, California. These surveys were conducted using the new MBARI Mapping Autonomous Underwater Vehicle (AUV). This torpedo-shaped, 6000 m deep rated vehicle is equipped with a 200 kHz multibeam sonar, 110 kHz and 410 kHz chirp sidescan sonar, and a 2-16 kHz sweep subbottom profiler. The sonar package can also be mounted on ROV Ventana, allowing near-bottom bathymetric surveys of sites where extreme topography (e.g. the Monterey Canyon axis) preclude safe autonomous operation. The Mapping AUV is being used to monitor sediment transport through Monterey Canyon by conducting repeated high-resolution bathymetric surveys in the upper canyon. Upper Monterey Canyon is known to have frequent sediment transport events. Four sites have been selected with canyon axis depths of 300 m, 520 m, 1000 m, and 1400 m, respectively. Each survey nominally covers a 600 m by 600 m area with a 35 m line spacing and a 20 m altitude. We are achieving sub-meter lateral resolution and a vertical precision of 0.3 m. The combined bathymetry and backscatter successfully image fine scale channel features, including bedforms, small scarps and plunge pools, and undercutting of the inner canyon walls. All four sites have been surveyed at least once, and we will revisit these sites three times annually for the foreseeable future. We have also collected in excess of 170 km of subbottom profiles around and across the upper canyon. The subbottom profiler successfully images sediment structure to subsurface depths of as much as 50 m. These profiles demonstrate that the upper canyon walls are draped with sediment rather than exposing an erosional surface. Another Mapping AUV survey target is Smooth Ridge, located immediately north of Monterey Canyon and west of Soquel canyon. The upper reaches of Smooth Ridge are connected to the shelf across a

  10. Environmental assessment of remedial action, acid/middle Pueblo Canyon, Los Alamos, New Mexico

    International Nuclear Information System (INIS)

    The radiological survey of the former radioactive waste treatment plant site (TA-45), Acid Canyon, and Pueblo Canyon found residual radioactivity at the site itself and in the channel and banks of Acid, Pueblo, and lower Los Alamos Canyons, all the way to the Rio Grande. The largest reservoir of radioactive material is in lower Pueblo Canyon, which is on DOE property. The only areas where residual radioactivity exceeds the proposed cleanup criteria are at the former vehicle decontamination facility, located between the former treatment plant site and Acid Canyon, around the former untreated waste outfall and for a short distance below, and in two small areas farther down in Acid Canyon. The three alternatives proposed are (1) to take no action, (2) to fence the areas where the residual radioactivity exceeds the proposed criteria (minimal action), and (3) to clean up the former vehicle decontamination facility and around the former untreated waste outfall. Calculations based on actual measurements indicate that the annual dose at the location having the greatest residual radioactivity would be about 12% of the applicable guideline. Most doses are much smaller than that. No environmental impacts are associated with either the no-action or minimal action alternatives. The impact associated with the cleanup alternative is very small. The preferred alternative is to clean up the areas around the former vehicle decontamination facility and the untreated waste outfall. This course of action is recommended not because of any real danger associated with the residual radioactivity, but rather because the cleanup operation is a minor effort and would conform with the ALARA (as low as reasonably achievable) philosophy

  11. Environmental analysis of Acid/middle Pueblo Canyon, Los Alamos, New Mexico

    International Nuclear Information System (INIS)

    The radiological survey of the former radioactive waste treatment plant site (TA-45), Acid Canyon, and Pueblo Canyon found residual radioactivity at the site itself and in the channel and banks of Acid, Pueblo, and lower Los Alamos Canyons, all the way to the Rio Grande. The largest reservoir of radioactive material is in lower Pueblo Canyon, which is on DOE property. The only areas where residual radioactivity exceeds the proposed cleanup criteria are at the former vehicle decontamination facility, located between the former treatment plant site and Acid Canyon, around the former untreated waste outfall and for a short distance below, and in two small areas farther down in Acid Canyon. The three alternatives proposed are (1) to take no action, (2) to fence the areas where the residual radioactivity exceeds the proposed criteria (minimal action), and (3) to clean up the former vehicle decontamination facility and around the former untreated waste outfall. Calculations based on actual measurements indicate that the annual dose at the location having the greatest residual radioactivity would be about 12% of the applicable guideline. Most doses are much smaller than that. No environmental impacts are associated with either the no-action or minimal action alternatives. The impact associated with the cleanup alternative is very small. The preferred alternative is to clean up the areas around the former vehicle decontamination facility and the untreated waste outfall. This course of action is recommended not because of any real danger associated with the residual radioactivity, but rather because the cleanup operation is a minor effort and would conform with the ALARA (as low as reasonably achievable) philosophy

  12. Environmental analysis of Acid/middle Pueblo Canyon, Los Alamos, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ferenbaugh, R.W.; Buhl, T.E.; Stoker, A.K.; Hansen, W.R.

    1982-08-01

    The radiological survey of the former radioactive waste treatment plant site (TA-45), Acid Canyon, and Pueblo Canyon found residual radioactivity at the site itself and in the channel and banks of Acid, Pueblo, and lower Los Alamos Canyons, all the way to the Rio Grande. The largest reservoir of radioactive material is in lower Pueblo Canyon, which is on DOE property. The only areas where residual radioactivity exceeds the proposed cleanup criteria are at the former vehicle decontamination facility, located between the former treatment plant site and Acid Canyon, around the former untreated waste outfall and for a short distance below, and in two small areas farther down in Acid Canyon. The three alternatives proposed are (1) to take no action, (2) to fence the areas where the residual radioactivity exceeds the proposed criteria (minimal action), and (3) to clean up the former vehicle decontamination facility and around the former untreated waste outfall. Calculations based on actual measurements indicate that the annual dose at the location having the greatest residual radioactivity would be about 12% of the applicable guideline. Most doses are much smaller than that. No environmental impacts are associated with either the no-action or minimal action alternatives. The impact associated with the cleanup alternative is very small. The preferred alternative is to clean up the areas around the former vehicle decontamination facility and the untreated waste outfall. This course of action is recommended not because of any real danger associated with the residual radioactivity, but rather because the cleanup operation is a minor effort and would conform with the ALARA (as low as reasonably achievable) philosophy.

  13. Canyon conditions impact carbon flows in food webs of three sections of the Nazare canyon

    NARCIS (Netherlands)

    van Oevelen, D.; Soetaert, K.; Garcia, R.; de Stigter, H.C.; Cunha, M.R.; Pusceddu, A.; Danovaro, R.; Garcia, R.

    2011-01-01

    Submarine canyons transport large amounts of sediment and organic matter (OM) from the continental shelf to the abyssal plain. Three carbon-based food web models were constructed for the upper (300-750 m water depth), middle (2700-3500 m) and lower section (4000-5000 m) of the Nazare canyon (eastern

  14. The Whittard Canyon – a case study of submarine canyon processes

    NARCIS (Netherlands)

    Amaro, T.; Huvenne, V.A.I.; Allcock, A.L.; Aslam, T.; Davies, J.S.; Danovaro, R.; de Stigter, H.C.; Duineveld, G.C.A.; Gambi, C.; Gooday, A.J.; Gunton, L.M.; Hall, R.; Howell, K.L.; Ingels, J.; Kiriakoulakis, K.; Kershaw, C.E.; Lavaleye, M.; Robert, K.; Stewart, H.; Van Rooij, D.; White, M.; Wilson, A.M.

    2016-01-01

    Submarine canyons are large geomorphological features that incise continental shelves and slopes around the world. They are often suggested to be biodiversity and biomass hotspots, although there is no consensus about this in the literature. Nevertheless, many canyons do host diverse faunal communit

  15. The Whittard Canyon – A case study of submarine canyon processes

    NARCIS (Netherlands)

    Amaro, T.; Huvenne, V.A.I.; Allcock, A.L.; Aslam, T.; Davies, J.S.; Danovaro, R.; de Stigter, H.C.; Duineveld, G.C.A.; Gambi, C.; Gooday, A.J.; Gunton, L.M.; Hall, R.; Howell, K.L.; Ingels, J.; Kiriakoulakis, K.; Kershaw, C.E.; Lavaleye, M.; Robert, K.; Stewart, H.; Van Rooij, D.; White, M.; Wilson, A.M.

    2016-01-01

    Submarine canyons are large geomorphological features that incise continental shelves and slopes around the world. They are often suggested to be biodiversity and biomass hotspots, although there is no consensus about this in the literature. Nevertheless, many canyons do host diverse faunal communit

  16. Phase I feasibility study for the Canyon disposition initiative (221-U facility)

    International Nuclear Information System (INIS)

    The objective of the Phase I Feasibility Study (FS) presented in this document is to provide decision makers sufficient information on the remedial alternatives specific to the disposition of the 221-U Canyon Building (221-U Facility) located at the Hanford Site, and to determine which alternatives are viable for further detailed analysis

  17. 75 FR 20381 - Glen Canyon Dam Adaptive Management Work Group (AMWG)

    Science.gov (United States)

    2010-04-19

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group (AMWG) AGENCY: Bureau of Reclamation... technical work group (TWG), a monitoring and research center, and independent review panels. The AMWG makes.... (PDT) to ensure that the connections work properly. The one hour test Web site is:...

  18. The effects of submarine canyons and the oxygen minimum zone on deep-sea fish assemblages off Hawai'i

    Science.gov (United States)

    De Leo, Fabio C.; Drazen, Jeffrey C.; Vetter, Eric W.; Rowden, Ashley A.; Smith, Craig R.

    2012-06-01

    Submarine canyons are reported to be sites of enhanced fish biomass and productivity on continental margins. However, little is known about the effects of canyons on fish biodiversity, in particular on oceanic islands, which are imbedded in regions of low productivity. Using submersibles and high-definition video surveys, we investigated demersal fish assemblages in two submarine canyons and slope areas off the island of Moloka'i, Hawai'i, at depths ranging from 314 to 1100 m. We addressed the interactions between the abundance, species richness and composition of the fish assemblage, and organic matter input and habitat heterogeneity, testing the hypotheses that heterogeneous bottom habitats and higher organic matter input in canyons enhance demersal fish abundance, and species density, richness and diversity, thereby driving differences in assemblage structure between canyons and slopes. Sediment type, substrate inclination, water-mass properties (temperature and dissolved oxygen) and organic matter input (modeled POC flux and percent detritus occurrence) were put into multivariate multiple regression models to identify potential drivers of fish assemblage structure. A total of 824 fish were recorded during ∼13 h of video yielding 55 putative species. Macrouridae was the most diverse family with 13 species, followed by Congridae (5), Ophidiidae (4) and Halosauridae (3). Assemblage structure changed markedly with depth, with the most abrupt change in species composition occurring between the shallowest stratum (314-480 m) and intermediate and deep strata (571-719 m, 946-1100 m). Chlorophthalmus sp. dominated the shallow stratum, macrourids and synaphobranchid eels at intermediate depths, and halosaurs in the deepest stratum. Assemblages only differed significantly between canyon and slope habitats for the shallow stratum, and the deep stratum at one site. Dissolved oxygen explained the greatest proportion of variance in the multivariate data, followed by POC

  19. TRAFFIC EMISSION TRANSPORTATION IN STREET CANYONS

    Institute of Scientific and Technical Information of China (English)

    XIE Xiao-min; WANG Jia-song; HUANG Zhen

    2009-01-01

    Spatial distributions of traffic-related pollutants in street canyons were investigated by field measurements and Computational Fluid Dynamics(CFD).Two typical street canyons were selected for field monitoring,and a three-dimensional numerical model was built based on Reynolds-averaged Navier-Stokes equations equipped with the standard k-ε turbulence models for CFD simulations.The study shows that the pollutant concentrations of vehicle emission correlate well with the traffic volume variation,wind direction and wind speed.The wind direction and speed at the roof level determine overwhellmingly the flow field and the distributions of pollutant concentrations in the street canyon.When the wind speed is equal to zero,the pollutant concentrations on the breath height of the both sides of the street canyon are almost the same.When the wind direction is perpendicular to the street,one main vortex is formed with a shape depending on the building structure on both sides of the street,the pollutant is accumulated on the leeward side,and the pollutant concentrations at the breath height on the leeward side are 2 to 3 times as those at the breath height on the windward side.If the wind direction makes some angles with the street canyon,the pollutant concentration will be higher on the leeward side because one main vortex will also be formed in the vertical section of the canyon by the perpendicular component of the wind.But pollutant concentrations decrease in the canyon because pollutants are dispersed along the axis of the street.Pollutants at different heights of the vertical section decrease with height,i.e.there are concentration gradients in the vertical section,and the pollutant concentrations on the leeward side of the upstream building are much higher than those on the windward side of the downstream building.

  20. Long-term surveillance plan for the Burro Canyon disposal cell Slick Rock, Colorado

    International Nuclear Information System (INIS)

    This long-term surveillance plan (LTSP) describes the U.S. Department of Energy (DOE) long-term care program for the Uranium Mill Tailings Remedial Action (UMTRA) Project Burro Canyon disposal cell in San Miguel County, Colorado. The U.S. Nuclear Regulatory Commission (NRC) developed regulations for the issuance of a general license for the custody and long-term care of UMTRA Project disposal sites in 10 CFR Part 40. The purpose of this general license is to ensure that the UMTRA Project disposal sites are cared for in a manner that protects the public health and safety and the environment. Before each disposal site is licensed, the NRC requires the DOE to submit a site-specific LTSP. The DOE prepared this LTSP to meet this requirement for the Burro Canyon disposal cell. The general license becomes effective when the NRC concurs with the DOE's determination that remedial action is complete at the Burro Canyon disposal cell and the NRC formally accepts this LTSP. Attachment 1 contains the concurrence letters from NRC. This LTSP describes the long-term surveillance program the DOE has implemented to ensure that the Burro Canyon disposal cell performs as designed. The program is based on site inspections to identify threats to disposal cell integrity. Ground water monitoring will not be required at the Burro Canyon disposal cell because the ground water protection strategy is supplemental standards based on low yield from the uppermost aquifer. The LTSP is based on the UMTRA Project's long-term surveillance program guidance and meets the requirements of 10 CFR 40.27(b) and 40 CFR 192.03

  1. Possible sources of archaeological maize found in Chaco Canyon and Aztec Ruin, New Mexico

    Science.gov (United States)

    Benson, L.V.; Stein, J.R.; Taylor, H.E.

    2009-01-01

    Maize played a major role in Chaco's interaction with outlying communities in the southern Colorado Plateau. This paper seeks to determine where archaeological corn cobs brought to Chaco Canyon were grown. Strontium-isotope and trace-metal ratios of 180 soil-water and 18 surface-water sites in the Southern Colorado Plateau have revealed possible source areas for some of 37 archaeological corn cobs from Chaco Canyon and 10 archaeological corn cobs from Aztec Ruin, New Mexico. The most probable source areas for cobs that predate the middle-12th-century drought include several Upper Rio Chaco sites (not including Chaco Canyon). There are many potential source areas for cobs that date to the late A.D. 1100s and early 1200s, all of which lie in the eastern part of the study area. Some Athapascan-age cobs have potential source areas in the Totah, Lobo Mesa, and Dinetah regions. One Gallo Cliff Dwelling cob has a strontium-isotope ratio that exceeds all measured soil-water values. Field sites for this cob may exist in association with Paleozoic and Precambrian rocks found 80-90 km from Chaco Canyon. Potential source areas for most Aztec Ruin cobs (many of which were found in rooms dating to the first half of the 13th-century) appear to be associated with a loess deposit that blankets the Mesa Verde and McElmo Dome regions.

  2. Geologic map of the Paintbrush Canyon Area, Yucca Mountain, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Dickerson, R.P. [Geological Survey, Denver, CO (United States); Drake, R.M. II [Pacific Western Technologies, Ltd., Lakewood, CO (United States)

    1998-11-01

    This geologic map is produced to support site characterization studies of Yucca Mountain, Nevada, site of a potential nuclear waste storage facility. The area encompassed by this map lies between Yucca Wash and Fortymile Canyon, northeast of Yucca Mountain. It is on the southern flank of the Timber Mountain caldera complex within the southwest Nevada volcanic field. Miocene tuffs and lavas of the Calico Hills Formation, the Paintbrush Group, and the Timber Mountain Group crop out in the area of this map. The source vents of the tuff cones and lava domes commonly are located beneath the thickest deposits of pyroclastic ejecta and lava flows. The rocks within the mapped area have been deformed by north- and northwest-striking, dominantly west-dipping normal faults and a few east-dipping normal faults. Faults commonly are characterized by well developed fault scarps, thick breccia zones, and hanging-wall grabens. Latest movement as preserved by slickensides on west-dipping fault scarps is oblique down towards the southwest. Two of these faults, the Paintbrush Canyon fault and the Bow Ridge fault, are major block-bounding faults here and to the south at Yucca Mountain. Offset of stratigraphic units across faults indicates that faulting occurred throughout the time these volcanic units were deposited.

  3. Tectonic activity and the evolution of submarine canyons: The Cook Strait Canyon system, New Zealand

    Science.gov (United States)

    Micallef, Aaron; Mountjoy, Joshu; Barnes, Philip; Canals, Miquel; Lastras, Galderic

    2016-04-01

    Submarine canyons are Earth's most dramatic erosional features, comprising steep-walled valleys that originate in the continental shelf and slope. They play a key role in the evolution of continental margins by transferring sediments into deep water settings and are considered important biodiversity hotspots, pathways for nutrients and pollutants, and analogues of hydrocarbon reservoirs. Although comprising only one third of continental margins worldwide, active margins host more than half of global submarine canyons. We still lack of thorough understanding of the coupling between active tectonics and submarine canyon processes, which is necessary to improve the modelling of canyon evolution in active margins and derive tectonic information from canyon morphology. The objectives of this study are to: (i) understand how tectonic activity influences submarine canyon morphology, processes, and evolution in an active margin, and (2) formulate a generalised model of canyon development in response to tectonic forcing based on morphometric parameters. We fulfil these objectives by analysing high resolution geophysical data and imagery from Cook Strait Canyon system, offshore New Zealand. Using these data, we demonstrate that tectonic activity, in the form of major faults and structurally-generated tectonic ridges, leaves a clear topographic signature on submarine canyon location and morphology, in particular their dendritic and sinuous planform shapes, steep and linear longitudinal profiles, and cross-sectional asymmetry and width. We also report breaks/changes in canyon longitudinal slope gradient, relief and slope-area regression models at the intersection with faults. Tectonic activity gives rise to two types of knickpoints in the Cook Strait Canyon. The first type consists of low slope gradient, rounded and diffusive knickpoints forming as a result of short wavelength folds or fault break outs and being restored to an equilibrium profile by upstream erosion and

  4. Nomograms for calculating pollution within street canyons

    Science.gov (United States)

    Buckland, A. T.; Middleton, D. R.

    The Environment Act 1995 has introduced the notion of local air quality management which requires that air quality in towns be reviewed and assessed. There is a need to identify those streets that are worst affected by vehicular pollutants. Such worst cases are likely to be narrow congested streets with tall buildings on each side. A nomogram presented here allows rapid screening of pollution in congested street canyons. The strong dependence on wind direction is reduced to the two extremes, namely wind along and wind across the canyon. Then canyon concentrations are estimated according to street geometry and traffic flow. The nomogram is designed for use by local authorities, is quick and easy to use, and paper or computer versions are available. It is suggested that detailed monitoring or modelling may only be required when simple screening methods predict high air pollution.

  5. 78 FR 21415 - Glen Canyon Dam Adaptive Management Work Group

    Science.gov (United States)

    2013-04-10

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group..., the AMWG, a technical work group, a Grand Canyon Monitoring and Research Center, and...

  6. 77 FR 9265 - Glen Canyon Dam Adaptive Management Work Group

    Science.gov (United States)

    2012-02-16

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group... Federal advisory committee, the AMWG, a technical work group (TWG), a Grand Canyon Monitoring and...

  7. 77 FR 43117 - Glen Canyon Dam Adaptive Management Work Group

    Science.gov (United States)

    2012-07-23

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group... Federal advisory committee, the AMWG, a technical work group (TWG), a Grand Canyon Monitoring and...

  8. 27 CFR 9.152 - Malibu-Newton Canyon.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Malibu-Newton Canyon. 9... Malibu-Newton Canyon. (a) Name. The name of the viticultural area described in this petition is “Malibu-Newton Canyon.” (b) Approved maps. The appropriate map for determining the boundary of the...

  9. Radionuclide contaminant analysis of small mammels, plants and sediments within Mortandad Canyon, 1994

    International Nuclear Information System (INIS)

    Small mammals, plants and sediments were sampled at one upstream location (Site 1) and two downstream locations (Site 2 and Site 3) from the National Pollution Discharge Elimination System outfall number-sign 051-051 in Mortandad Canyon, Los Alamos County, New Mexico. The purpose of the sampling was to identify radionuclides potentially present, to quantitatively estimate and compare the amount of radionuclide uptake at specific locations (Site 2 and Site 3) within Mortandad Canyon to an upstream site (Site 1), and to identify the primary mode (inhalation ingestion, or surface contact) of contamination to small mammals. Three composite samples of at least five animals per sample were collected at each site. Pelts and carcasses of each animal were separated and analyzed independently. In addition, three composite samples were also collected for plants and sediments at each site. Samples were analyzed for 241Am, 90Sr, 238Pu, 239Pu, and total U. With the exception of total U, all mean radionuclide concentrations in small mammal carcasses and sediments were significantly higher at Site 2 than Site 1 or Site 3. No differences were detected in the mean radionuclide concentration of plant samples between sites. However, some radionuclide concentrations found at all three sites were higher than regional background. No differences were found between mean carcass radionuclide concentrations and mean pelt radionuclide concentrations, indicating that the two primary modes of contamination may be equally occurring

  10. Let's Bet on Sediments! Hudson Canyon Cruise--Grades 9-12. Focus: Sediments of Hudson Canyon.

    Science.gov (United States)

    National Oceanic and Atmospheric Administration (DOC), Rockville, MD.

    These activities are designed to teach about the sediments of Hudson Canyon. Students investigate and analyze the patterns of sedimentation in the Hudson Canyon, observe how heavier particles sink faster than finer particles, and learn that submarine landslides are avalanches of sediment in deep ocean canyons. The activity provides learning…

  11. Geohydrology of White Rock Canyon of the Rio Grande from Otowi to Frijoles Canyon

    International Nuclear Information System (INIS)

    Twenty-seven springs discharge from the Totavi Lentil and Tesuque Formation in White Rock Canyon. Water generally acquires its chemical characteristics from rock units that comprise the spring aquifer. Twenty-two of the springs are separated into three groups of similar aquifer-related chemical quality. The five remaining springs make up a fourth group with a chemical quality that differs due to localized conditions in the aquifer. Localized conditions may be related to recharge or discharge in or near basalt intrusion or through faults. Streams from Pajarito, Ancho, and Frijoles Canyons discharge into the Rio Grande in White Rock Canyon. The base flow in the streams is from springs. Sanitary effluent in Mortandad Canyon from the treatment plant at White Rock also reaches the Rio Grande

  12. Examinations of samples of Bell Canyon Test 1-FF grout

    International Nuclear Information System (INIS)

    Portland cement grout identified as BCT-1-FF (Bell Canyon Test 1-FF) was used in borehole plugging experiments of the Bell Canyon Tests in Holl AEC-7 at the Waste Isolation Pilot Plant site in New Mexico during September 1979 and February 1980. This grout was made with fresh water. A study of this grout was begun in August 1979 in the laboratory to evauate the possible effects of temperature, pressure, and storage in fresh water or simulated groundwater (brine) on its phase composition and compressive strength at early ages. Phase composition was determined by X-ray diffraction. Temperatures ranged up to about 1500F and included elevation at a few hours age after mixing; pressure was as high as 1500 psi; specimens were stored in simulated groundwater (brine) or in fresh water. Data from 1 to 90 days showed: (a) Higher temperature accelerated early strength gain. These differences essentially vanished by 90 days age. (b) Hydration products as identified by X-ray diffraction were normal; this indicated that a temperature range of 78 to 1530F was not significant. (c) Pressure did not affect composition. (d) Storage in simulated groundwater (brine) or fresh water had no detectable effect. (e) Since the BCT-1-FF grout mixture contained added sulfate, it formed more ettringite as judged by X-ray diffraction than comparable portland cement mixtures without added sulfate

  13. Multidimensional analysis of Drosophila wing variation in Evolution Canyon

    Indian Academy of Sciences (India)

    Vincent Debat; Raphael Cornette; Abraham B. Koral; Eviatar Nevo; David Soulet; Jean R. David

    2008-12-01

    Environmental stress has been suggested to be a major evolutionary force, both through inducing strong selection and because of its direct impact on developmental buffering processes that alter the evolvability of organisms. In particular, temperature has attracted much attention because of its importance as an ecological feature and the relative ease with which it can be experimentally manipulated in the lab. Evolution Canyon, Lower Nahal Oren, Israel, is a well studied natural site where ecological parameters are suspected to drive evolutionary differentiation. In this study, using Drosophila melanogaster isofemale lines derived from wild flies collected on both slopes of the canyon, we investigated the effect of developmental temperature upon the different components of phenotypic variation of a complex trait: the wing. Combining geometric and traditional morphometrics, we find only limited evidence for a differentiation among slopes. Investigating simultaneously phenotypic plasticity, genetic variation among isofemale lines, variation among individuals and fluctuating asymmetry, we could not identify a consistent effect of the stressful conditions encountered on the south facing slope. The prevailing structuring effect is that of the experimentally manipulated temperature which clearly influences wing mean size and shape. Variability, in contrast, is not consistently affected by temperature. Finally, we investigated the specific relationship between individual variation and fluctuating asymmetry. Using metric multi-dimensional scaling we show that the related patterns of wing shape variation are not identical, supporting the view that the underlying developmental processes are to a certain extent different.

  14. 78 FR 7775 - Boulder Canyon Project

    Science.gov (United States)

    2013-02-04

    .... \\1\\ 75 FR 57912 (September 23, 2010). \\2\\ 133 FERC ] 62,229. The proposed BCP electric service base... in power rate adjustments (10 CFR part 903) were published on September 18, 1985 (50 FR 87835... Area Power Administration Boulder Canyon Project AGENCY: Western Area Power Administration, DOE....

  15. ACUMEN 2012: Atlantic Canyons Undersea Mapping Expeditions

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Between February and August 2012, a team of NOAA and external partners will conduct a mapping ‘blitz’ focused on deepwater canyons off the northeastern...

  16. Anatomy of La Jolla submarine canyon system; offshore southern California

    Science.gov (United States)

    Paull, C.K.; Caress, D.W.; Lundsten, E.; Gwiazda, R.; Anderson, K.; McGann, M.; Conrad, J.; Edwards, B.; Sumner, E.J.

    2013-01-01

    An autonomous underwater vehicle (AUV) carrying a multibeam sonar and a chirp profiler was used to map sections of the seafloor within the La Jolla Canyon, offshore southern California, at sub-meter scales. Close-up observations and sampling were conducted during remotely operated vehicle (ROV) dives. Minisparker seismic-reflection profiles from a surface ship help to define the overall geometry of the La Jolla Canyon especially with respect to the pre-canyon host sediments. The floor of the axial channel is covered with unconsolidated sand similar to the sand on the shelf near the canyon head, lacks outcrops of the pre-canyon host strata, has an almost constant slope of 1.0° and is covered with trains of crescent shaped bedforms. The presence of modern plant material entombed within these sands confirms that the axial channel is presently active. The sand on the canyon floor liquefied during vibracore collection and flowed downslope, illustrating that the sediment filling the channel can easily fail even on this gentle slope. Data from the canyon walls help constrain the age of the canyon and extent of incision. Horizontal beds of moderately cohesive fine-grained sediments exposed on the steep canyon walls are consistently less than 1.232 million years old. The lateral continuity of seismic reflectors in minisparker profiles indicate that pre-canyon host strata extend uninterrupted from outside the canyon underneath some terraces within the canyon. Evidence of abandoned channels and point bar-like deposits are noticeably absent on the inside bend of channel meanders and in the subsurface of the terraces. While vibracores from the surface of terraces contain thin (< 10 cm) turbidites, they are inferred to be part of a veneer of recent sediment covering pre-canyon host sediments that underpin the terraces. The combined use of state of the art seafloor mapping and exploration tools provides a uniquely detailed view of the morphology within an active submarine canyon.

  17. Colorado River campsite monitoring, Grand Canyon National Park, Arizona, 1998-2012

    Science.gov (United States)

    Kaplinski, Matt; Hazel, Joe; Parnell, Rod; Hadley, Daniel R.; Grams, Paul

    2014-01-01

    River rafting trips and hikers use sandbars along the Colorado River in Marble and Grand Canyons as campsites. The U.S. Geological Survey evaluated the effects of Glen Canyon Dam operations on campsite areas on sandbars along the Colorado River in Grand Canyon National Park. Campsite area was measured annually from 1998 to 2012 at 37 study sites between Lees Ferry and Diamond Creek, Arizona. The primary purpose of this report is to present the methods and results of the project. Campsite area surveys were conducted using total station survey methods to outline the perimeter of camping area at each study site. Campsite area is defined as any region of smooth substrate (most commonly sand) with no more than an 8 degree slope and little or no vegetation. We used this definition, but relaxed the slope criteria to include steeper areas near boat mooring locations where campers typically establish their kitchens. The results show that campsite area decreased over the course of the study period, but at a rate that varied by elevation zone and by survey period. Time-series plots show that from 1998 to 2012, high stage-elevation (greater than the 25,000 ft3/s stage-elevation) campsite area decreased significantly, although there was no significant trend in low stage-elevation (15,000–20,000 ft3/s) campsite area. High stage-elevation campsite area increased after the 2004 and 2008 high flows, but decreased in the intervals between high flows. Although no overall trend was detected for low stage-elevation campsite areas, they did increase after high-volume dam releases equal to or greater than about 20,000 ft3/s. We conclude that dam operations have not met the management objectives of the Glen Canyon Adaptive Management program to increase the size of camping beaches in critical and non-critical reaches of the Colorado River between Glen Canyon Dam and Lake Mead.

  18. A Simplified Simulation Model for Predicting Radiative Transfer in Long Street Canyons under High Solar Radiation Conditions

    Directory of Open Access Journals (Sweden)

    Carlos Rubio-Bellido

    2015-12-01

    Full Text Available Modeling solar radiation in street canyons is crucial to understanding the solar availability of building façades. This article describes the implementation of a simulation routine, developed in the Matlab® computer language, which is aimed at predicting solar access for building façades located in dense urban conglomerates comprising deep long street canyons, under high solar radiation conditions, typical in southern countries of Europe. Methodology is primarily based on the configuration factor theory, also aided by computer simulation, which enables to assess the interplay between the surfaces that compose the so-called street canyon. The results of the theoretical model have been cross-checked and verified by on-site measurements in two real case studies, two streets in Cadiz and Seville. The simplified simulation reproduces the shape of the curve for on-site measured values and weighted errors for the whole model do not surpass 10%, with a maximum of 9.32% and a mean values of 6.31%. As a result, a simplified predictive model that takes into account direct, diffuse and reflected solar radiation from the surfaces that enclose the canyon, has been devised. The authors consider that this research provides further improvement, as well as a handy alternative approach, to usual methods used for the calculation of available solar radiation in urban canyons, such as the Sky View Factor or the ray tracing.

  19. The Bayo Canyon/radioactive lanthanum (RaLa) program

    Energy Technology Data Exchange (ETDEWEB)

    Dummer, J.E.; Taschner, J.C.; Courtright, C.C.

    1996-04-01

    LANL conducted 254 radioactive lanthanum (RaLa) implosion experiments Sept. 1944-March 1962, in order to test implosion designs for nuclear weapons. High explosives surrounding common metals (surrogates for Pu) and a radioactive source containing up to several thousand curies of La, were involved in each experiment. The resulting cloud was deposited as fallout, often to distances of several miles. This report was prepared to summarize existing records as an aid in evaluating the off-site impact, if any, of this 18-year program. The report provides a historical setting for the program, which was conducted in Technical Area 10, Bayo Canyon about 3 miles east of Los Alamos. A description of the site is followed by a discussion of collateral experiments conducted in 1950 by US Air Force for developing an airborne detector for tracking atmospheric nuclear weapons tests. All known off-site data from the RaLa program are tabulated and discussed. Besides the radiolanthanum, other potential trace radioactive material that may have been present in the fallout is discussed and amounts estimated. Off-site safety considerations are discussed; a preliminary off-site dose assessment is made. Bibliographical data on 33 persons important to the program are presented as footnotes.

  20. Results from the Bell Canyon borehole plugging test

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, C. L.

    1980-01-01

    The BHP is an integrated program involving consequence assessment and plug performance calculations, materials evaluation, instrumentation development and field testing, and interfaces directly with other WIPP-related activities. This paper describes an in situ test conducted under the BHP Field Test Task. The Bell Canyon Test was conducted to evaluate candidate grout plugging mixes and plug emplacement techniques, and to assess plug performance under in-situ cure conditions. Laboratory testing of the brine-grout/rock combination revealed an adverse reaction between the brine-grout and the anhydrite. This discovery permitted a timely change to an additional laboratory compatibility testing program with an alternate fresh-water mix to permit maintenance of the test schedule with little delay. While cement emplacement technology is generally adequate to satisfy repository plugging requirements, plug compatibility with the host rock must be carefully assessed for each repository site. Generally accepted laboratory cement-testing techniques need to include flow characteristics and geochemical stability.

  1. Evaluation of air quality and noise impact assessments, Davis Canyon

    International Nuclear Information System (INIS)

    In this report, several issues are identified regarding the air quality and noise assessments presented in the final salt repository environmental assessment (EA) prepared by the US Department of Energy for the Davis Canyon, Utah, site. Necessary revisions to the data and methods used to develop the EA impact assessment are described. Then, a comparative evaluation is presented in which estimated impacts based upon the revised data and methods are compared with the impacts published in the EA. The evaluation indicates that the conclusions of the EA air quality and noise impact sections would be unchanged. Consequently, the guideline findings presented in Chapter 6 of the EA are also unchanged by the revised analysis. 50 refs., 16 tabs

  2. Surprise and opportunity for learning in Grand Canyon: the Glen Canyon Dam Adaptive Management Program

    Science.gov (United States)

    Melis, Theodore S.; Walters, Carl; Korman, Josh

    2015-01-01

    With a focus on resources of the Colorado River ecosystem below Glen Canyon Dam, the Glen Canyon Dam Adaptive Management Program has included a variety of experimental policy tests, ranging from manipulation of water releases from the dam to removal of non-native fish within Grand Canyon National Park. None of these field-scale experiments has yet produced unambiguous results in terms of management prescriptions. But there has been adaptive learning, mostly from unanticipated or surprising resource responses relative to predictions from ecosystem modeling. Surprise learning opportunities may often be viewed with dismay by some stakeholders who might not be clear about the purpose of science and modeling in adaptive management. However, the experimental results from the Glen Canyon Dam program actually represent scientific successes in terms of revealing new opportunities for developing better river management policies. A new long-term experimental management planning process for Glen Canyon Dam operations, started in 2011 by the U.S. Department of the Interior, provides an opportunity to refocus management objectives, identify and evaluate key uncertainties about the influence of dam releases, and refine monitoring for learning over the next several decades. Adaptive learning since 1995 is critical input to this long-term planning effort. Embracing uncertainty and surprise outcomes revealed by monitoring and ecosystem modeling will likely continue the advancement of resource objectives below the dam, and may also promote efficient learning in other complex programs.

  3. NO2 photolysis frequencies in street canyons

    Science.gov (United States)

    Koepke, P.; Garhammer, M.; Hess, M.; Roeth, E.-P.

    2010-08-01

    Photolysis frequencies for NO2 are modeled for the conditions in urban streets, which are taken into account as canyons with variable height and width. The effect of a street canyon is presented with absolute values and as a ratio RJ of the photolysis frequency within the street compared to that with free horizon. This allows further use of the existing photolysis parameterizations. Values are presented for variable solar elevation and azimuth angles, varying atmospheric conditions and different street properties. The NO2 photolysis frequency in a street depends strongly on the relative width of the street and its orientation towards the sun. Averaged over atmospheric conditions and street orientation, the NO2 photolysis frequency is reduced in comparison with the values for free horizon: to less than 20% for narrow skyscraper streets, to about 40% for typical urban streets, and only to about 80% for garden streets. A parameterization with the global solar irradiance is given for the averaged RJ values.

  4. NO2 photolysis frequencies in street canyons

    Directory of Open Access Journals (Sweden)

    E.-P. Roeth

    2010-05-01

    Full Text Available Photolysis frequencies for NO2 are modeled for the conditions in urban streets, which are taken into account as canyons with variable height and width. The effect of a street canyon is presented with absolute values and as a ratio RJ of the photolysis frequency within the street against those with free horizon, which allows further use of the existing photolysis parameterizations. Values are presented for variable solar elevation and azimuth angles, varying atmospheric conditions and different street properties. The NO2 photolysis frequency in the street, averaged over atmospheric conditions and street orientation, is reduced to less than 20% for narrow streets, to about 40% for typical urban streets, and only to about 80% for garden streets, each with about ±5% uncertainty. A parameterization of RJ with the global solar irradiance is given for values that are averaged over the meteorological conditions and the street orientation.

  5. Turbulent ventilation of a street canyon

    DEFF Research Database (Denmark)

    Nielsen, Morten

    2000-01-01

    A selection of turbulence data corresponding to 185 days of field measurements has een analysed. The non-ideal building geometry influenced the circulation patterns in the street canyon and the largest average vertical velocities were observed in the wake of an unbroken line of buildings. The...... small, and this suggests that most of the velocity fluctuations were fairly local and not caused by unsteady street vortices. The observed velocities scaled with the ambient wind speed except under low-wind conditions....

  6. “SHANGRI-LA” IN NUJIANG CANYON

    Institute of Scientific and Technical Information of China (English)

    李晓勤

    2004-01-01

    A few hours' drive took me to a place called Bingzhongluo,the largest piece of flatland in the canyon,where the Nujiang River takes two abrupt turns, forming the first bend on the Nujiang River,which is a best known scenic spot in China. At the side of the river there is a tablet of pure white marble inscribed with words painted in bright red,reading:“Bingzhongluo,the Shangri-La.”

  7. Aquatic macroinvertebrates and water quality of Sandia Canyon, Los Alamos National Laboratory, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Cross, S.; Nottelman, H.

    1997-01-01

    The Biology Team of ESH-20 (the Ecology Group) at Los Alamos National Laboratory (LANL) has collected samples from the stream within Sandia Canyon since the summer of 1990. These field studies measure water quality parameters and collect aquatic macroinvertebrates from sampling sites within the upper canyon stream. Reports by Bennett and Cross discuss previous aquatic studies in Sandia Canyon. This report updates and expands the previous findings. The Biology Team collected water quality data and aquatic macroinvertebrates monthly at three sampling stations within Sandia Canyon in 1995. The two upstream stations occur near a cattail (Typha latifolia) dominated marsh downstream from outfalls that discharge industrial and sanitary waste effluent into the stream, thereby maintaining year-round flow. The third station is approximately 1.5 miles downstream from the outfalls within a mixed conifer forest. All water chemistry parameters measured in Sandia Canyon during 1995 fell within acceptable State limits and scored in the {open_quotes}good{close_quotes} or {open_quotes}excellent{close_quotes} ranges when compared to an Environmental Quality Index. However, aquatic macroinvertebrates habitats have been degraded by widespread erosion, channelization, loss of wetlands due to deposition and stream lowering, scour, limited acceptable substrates, LANL releases and spills, and other stressors. Macroinvertebrate communities at all the stations had low diversities, low densities, and erratic numbers of individuals. These results indicate that although the stream possesses acceptable water chemistry, it has reduced biotic potential. The best developed aquatic community occurs at the sampling station with the best habitat and whose downstream location partially mitigates the effects of upstream impairments.

  8. Deep-sea foraminifera from the Cassidaigne Canyon (NW Mediterranean): Assessing the environmental impact of bauxite red mud disposal

    NARCIS (Netherlands)

    Fontanier, C.; Fabri, M.-C.; Buscail, R.; Biscara, L.; Koho, K.A.; Reichart, G.-J.; Cossa, D.; Galaup, S.; Chabaud, G.; Pigot, L.

    2012-01-01

    Benthic foraminiferal assemblages were investigated from two sites along the axis of the Cassidaigne Canyon (NW Mediterranean Sea). Both areas are contaminated by bauxite red mud enriched in iron, titanium, vanadium and chromium. These elemental enrichments are related to bauxite-derived minerals an

  9. Typhoon associated hyperpycnal turbidity current in a submarine canyon off a river mouth

    Science.gov (United States)

    Hsu, R. T.; Liu, J. T.

    2013-12-01

    Canyon bathy contour (From Center for Space and Remote Sensing Research-CSRSR, National Central University, Taiwan). The pink line illustrated the thalweg of the submarine canyon. Two mooring's locations were pointed out by red circle in the thalweg. Another red circle was the weather buoy site maintained by CWB.

  10. 2007 Weather and Aeolian Sand-Transport Data from the Colorado River Corridor, Grand Canyon, Arizona

    Science.gov (United States)

    Draut, Amy E.; Andrews, Timothy; Fairley, Helen C.; Brown, Christopher R.

    2009-01-01

    Weather data constitute an integral part of ecosystem monitoring in the Colorado River corridor and are particularly valuable for understanding processes of landscape change that contribute to the stability of archeological sites. Data collected in 2007 are reported from nine weather stations in the Colorado River corridor through Grand Canyon, Ariz. The stations were deployed in February and March 2007 to measure wind speed and direction, rainfall, air temperature, relative humidity, and barometric pressure. Sand traps near each weather station collect windblown sand, from which daily aeolian sand-transport rates are calculated. The data reported here were collected as part of an ongoing study to test and evaluate methods for quantifying processes that affect the physical integrity of archeological sites along the river corridor; as such, these data can be used to identify rainfall events capable of causing gully incision and to predict likely transport pathways for aeolian sand, two landscape processes integral to the preservation of archeological sites. Weather data also have widespread applications to other studies of physical, cultural, and biological resources in Grand Canyon. Aeolian sand-transport data reported here, collected in the year before the March 2008 High-Flow Experiment (HFE) at Glen Canyon Dam, represent baseline data against which the effects of the 2008 HFE on windblown sand will be compared in future reports.

  11. Ventilation Processes in a Three-Dimensional Street Canyon

    Science.gov (United States)

    Nosek, Štěpán; Kukačka, Libor; Kellnerová, Radka; Jurčáková, Klára; Jaňour, Zbyněk

    2016-05-01

    The ventilation processes in three different street canyons of variable roof geometry were investigated in a wind tunnel using a ground-level line source. All three street canyons were part of an urban-type array formed by courtyard-type buildings with pitched roofs. A constant roof height was used in the first case, while a variable roof height along the leeward or windward walls was simulated in the two other cases. All street-canyon models were exposed to a neutrally stratified flow with two approaching wind directions, perpendicular and oblique. The complexity of the flow and dispersion within the canyons of variable roof height was demonstrated for both wind directions. The relative pollutant removals and spatially-averaged concentrations within the canyons revealed that the model with constant roof height has higher re-emissions than models with variable roof heights. The nomenclature for the ventilation processes according to quadrant analysis of the pollutant flux was introduced. The venting of polluted air (positive fluctuations of both concentration and velocity) from the canyon increased when the wind direction changed from perpendicular to oblique, irrespective of the studied canyon model. Strong correlations (>0.5) between coherent structures and ventilation processes were found at roof level, irrespective of the canyon model and wind direction. This supports the idea that sweep and ejection events of momentum bring clean air in and detrain the polluted air from the street canyon, respectively.

  12. Benthic foraminiferal thanatocoenoses from the Cap-Ferret Canyon area (NE Atlantic): A complex interplay between hydro-sedimentary and biological processes

    Science.gov (United States)

    Duros, P.; Jorissen, F. J.; Cesbron, F.; Zaragosi, S.; Schmidt, S.; Metzger, E.; Fontanier, C.

    2014-06-01

    Benthic foraminiferal thanatocoenoses from the Cap-Ferret Canyon area were studied in the >150-μm fraction of 4-5 cm deep sediment levels, at 13 stations. The shallowest station (151 m depth) is located at the shelf break, close to the canyon head. All other stations are located along two bathymetric transects: seven stations along the canyon axis between 300 and 3000 m depth, and five stations from 300 m to 2000 m depth along the southern flank of the canyon. The comparison between the live (Rose-Bengal-stained) and dead assemblages shows that biological (i.e. population dynamic) and taphonomic processes (i.e. test destruction, transport) generate important discrepancies between live and dead assemblages. An important question is, to what degree post-mortem transport and redeposition of foraminiferal tests contribute to the difference between living and dead assemblages? The composition of the thanatocoenoses (shells >150 μm from the inner continental shelf to the Cap-Ferret Canyon axis. However, transport of tests from outer shelf or upper canyon axis towards deeper sites occurs, as indicated by an increase of diversity indices of the dead fauna along the canyon axis. Moreover, some species (e.g., Cassidulina carinata) are observed in the living fauna restricted to the shallow sites, but occur in important amounts in the dead fauna at deeper stations, suggesting that these taxa have been transported from upper canyon stations toward deeper sites. Since Cap-Ferret Canyon is inactive in terms of massive sediment transport (i.e. gravity events), downslope transport of foraminiferal tests probably takes place in nepheloid layers. Downslope transports of foraminiferal tests may create important biases for the utilisation of paleoceanographic proxies using the assemblage characteristics and/or the geochemical composition of selected species. However, the study of dead assemblages along a canyon axis can give important clues about the sedimentary dynamics, especially

  13. Anti-plane deformations around arbitrary-shaped canyons on a wedge-shape half-space: moment method solutions

    Institute of Scientific and Technical Information of China (English)

    Nazaret Dermendjian; Vincent W. Lee; Jianwen Liang(梁建文)

    2003-01-01

    The wave propagation behavior in an elastic wedge-shaped medium with an arbitrary shaped cylindrical canyon at its vertex has been studied. Nunerical computation of the wave displacement field is carried out on and near the canyon surfaces using weighted-residuals (moment method). The wave displacement fields are computed by the residual mcthod for the cases of elliptic, circular, rounded-rectangular and flat-elliptic canyons. The analysis demonstrates that thc resulting surface displacemcnt depends, as in similar previous analyses, on several factors including, but not limited, to the angle of thc wedge, thc geometry of thc vertex, the frcquencies of thc incident waves, the angles of incidence, and the material properties of the media. The analysis provides intriguing results that help to explain geophysical observations regarding the amplification of seismic energy as a function of site conditions.

  14. Ascension Submarine Canyon, California - Evolution of a multi-head canyon system along a strike-slip continental margin

    Science.gov (United States)

    Nagel, D.K.; Mullins, H.T.; Greene, H. Gary

    1986-01-01

    Ascension Submarine Canyon, which lies along the strike-slip (transform) dominated continental margin of central California, consists of two discrete northwestern heads and six less well defined southeastern heads. These eight heads coalesce to form a single submarine canyon near the 2700 m isobath. Detailed seismic stratigraphic data correlated with 19 rock dredge hauls from the walls of the canyon system, suggest that at least one of the two northwestern heads was initially eroded during a Pliocene lowstand of sea level ???3.8 m.y. B.P. Paleogeographic reconstructions indicate that at this time, northwestern Ascension Canyon formed the distal channel of nearby Monterey Canyon and has subsequently been offset by right-lateral, strike-slip faulting along the San Gregorio fault zone. Some of the six southwestern heads of Ascension Canyon may also have been initially eroded as the distal portions of Monterey Canyon during late Pliocene-early Pleistocene sea-level lowstands (???2.8 and 1.75 m.y. B.P.) and subsequently truncated and offset to the northwest. There have also been a minimum of two canyon-cutting episodes within the past 750,000 years, after the entire Ascension Canyon system migrated to the northwest past Monterey Canyon. We attribute these late Pleistocene erosional events to relative lowstands of sea level 750,000 and 18,000 yrs B.P. The late Pleistocene and Holocene evolution of the six southeastern heads also appears to have been controlled by structural uplift of the Ascension-Monterey basement high at the southeastern terminus of the Outer Santa Cruz Basin. We believe that uplift of this basement high sufficiently oversteepened submarine slopes to induce gravitational instability and generate mass movements that resulted in the erosion of the canyon heads. Most significantly, though, our results and interpretations support previous proposals that submarine canyons along strike-slip continental margins can originate by tectonic trunction and lateral

  15. Grand Canyon 10 x 20 NTMS area: Arizona. Data report

    International Nuclear Information System (INIS)

    This data report presents results of ground water and stream/surface sediment reconnaissance in the National Topographic Map Series (NTMS) Grand Canyon 10 x 20 quadrangle. Surface samples (sediment) were collected from 1013 sites. The target sampling density was one site per 16 square kilometers (six square miles). Ground water samples were collected at 84 sites. Neutron activation analysis (NAA) results are given for uranium and 16 other elements in sediments, and for uranium and 9 other elements in ground water. Mass spectrometry results are given for helium in ground water. Field measurements and observations are reported for each site. Analytical data and field measurements are presented in tables and maps. Statistical summaries of data and a brief description of results are given. A generalized geologic map and a summary of the geology of the area are included. Data from ground water sites (on microfiche in pocket) include (1) water chemistry measurements (pH, conductivity, and alkalinity), (2) physical measurements where applicable (water temperature, well description, and scintillometer reading), and (3) elemental analyses (U, Al, Br, Cl, Dy, F, He, Mg, Mn, Na, and V). Data from sediment sites (also on microfiche in pocket) include (1) stream water chemistry measurements (pH, conductivity, and alkalinity), and (2) elemental analyses for sediment samples (U, Th, Hf, Al, Ce, Dy, Eu, Fe, La, Lu, Mn, Sc, Sm, Na, Ti, V, and Yb). Sample site descriptors (stream characteristics, vegetation, etc.) are also tabulated. Areal distribution maps, histograms, and cumulative frequency plots for most elements, U/Th, U/Hf, and Th/La ratios, and scintillometer readings for sediment samples are included on the microfiche

  16. Site selection

    International Nuclear Information System (INIS)

    The conditions and criteria for selecting a site for a nuclear weapons test at the Nevada Test Site are summarized. Factors considered are: (1) scheduling of drill rigs, (2) scheduling of site preparation (dirt work, auger hole, surface casing, cementing), (3) schedule of event (when are drill hole data needed), (4) depth range of proposed W.P., (5) geologic structure (faults, Pz contact, etc.), (6) stratigraphy (alluvium, location of Grouse Canyon Tuff, etc.), (7) material properties (particularly montmorillonite and CO2 content), (8) water table depth, (9) potential drilling problems (caving), (10) adjacent collapse craters and chimneys, (11) adjacent expended but uncollapsed sites, (12) adjacent post-shot or other small diameter holes, (13) adjacent stockpile emplacement holes, (14) adjacent planned events (including LANL), (15) projected needs of Test Program for various DOB's and operational separations, and (16) optimal use of NTS real estate

  17. Flow structures and sandbar dynamics in a canyon river during a controlled flood, Colorado River, Arizona

    Science.gov (United States)

    Wright, S.A.; Kaplinski, M.

    2011-01-01

    In canyon rivers, debris fan constrictions create rapids and downstream pools characterized by secondary flow structures that are closely linked to channel morphology. In this paper we describe detailed measurements of the three-dimensional flow structure and sandbar dynamics of two pools along the Colorado River in the Grand Canyon during a controlled flood release from Glen Canyon Dam. Results indicate that the pools are characterized by large lateral recirculation zones (eddies) resulting from flow separation downstream from the channel constrictions, as well as helical flow structures in the main channel and eddy. The lateral recirculation zones are low-velocity areas conducive to fine sediment deposition, particularly in the vicinity of the separation and reattachment points and are thus the dominant flow structures controlling sandbar dynamics. The helical flow structures also affect morphology but appear secondary in importance to the lateral eddies. During the controlled flood, sandbars in the separation and reattachment zones at both sites tended to build gradually during the rising limb and peak flow. Deposition in shallow water on the sandbars was accompanied by erosion in deeper water along the sandbar slope at the interface with the main channel. Erosion occurred via rapid mass failures as well as by gradual boundary shear stress driven processes. The flow structures and morphologic links at our study sites are similar to those identified in other river environments, in particular sharply curved meanders and channel confluences where the coexistence of lateral recirculation and helical flows has been documented. Copyright 2011 by the American Geophysical Union.

  18. 78 FR 7810 - Glen Canyon Dam Adaptive Management Work Group

    Science.gov (United States)

    2013-02-04

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group.... L. 102-575) of 1992. The AMP includes a Federal advisory committee, the AMWG, a technical work...

  19. 76 FR 24516 - Glen Canyon Dam Adaptive Management Work Group

    Science.gov (United States)

    2011-05-02

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Glen Canyon Dam Adaptive Management Work Group...-575) of 1992. The AMP includes a Federal advisory committee, the AMWG, a technical work group (TWG),...

  20. 75 FR 34476 - Glen Canyon Dam Adaptive Management Work Group

    Science.gov (United States)

    2010-06-17

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation... Interior (Secretary) is renewing the charter for the Glen Canyon Dam Adaptive Management Work Group. The purpose of the Adaptive Management Work Group is to advise and to provide recommendations to the...

  1. 36 CFR 7.4 - Grand Canyon National Park.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Grand Canyon National Park. 7.4 Section 7.4 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.4 Grand Canyon National Park. (a)...

  2. Modeling the Effect of Wider Canyons on Urban Heating

    Directory of Open Access Journals (Sweden)

    Rizwan Ahmed Memon

    2011-04-01

    Full Text Available The k-? turbulence model is adopted in this study to simulate the impact of street canyon AR (Aspect Ratios on heating within street canyon. The two-dimensional model was validated for RANS (Reynolds Averaged Navier Stokes and energy transport equations. The validation process confirms that the results of the model for airtemperature and wind speed could be trusted. The application of the said model is carried out to ideal street canyons of ARs (ratio of building-height-to-street-width from 0.4 to 2 with the same boundary conditions. Notably, street canyon aspect ratio was calculated by varying the street width while keeping the building height constant. Results show that the weighted-average-air-temperature within AR 0.4 was around 0.8% (i.e. 2.4K higher than that within AR 2.0. Conversely, there was strong correlation (i.e., R2>0.9 between air temperature within the street canyon and street canyon AR. Results demonstrate stronger influence of vertical velocity on heating within street canyon. Evidently, increased vertical velocity decreased the temperatures. Conversely, temperatures were higher along the leeward side of the canyon in lower ARs.

  3. Big Canyon Creek Ecological Restoration Strategy.

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, Lynn; Richardson, Shannon

    2007-10-01

    He-yey, Nez Perce for steelhead or rainbow trout (Oncorhynchus mykiss), are a culturally and ecologically significant resource within the Big Canyon Creek watershed; they are also part of the federally listed Snake River Basin Steelhead DPS. The majority of the Big Canyon Creek drainage is considered critical habitat for that DPS as well as for the federally listed Snake River fall chinook (Oncorhynchus tshawytscha) ESU. The Nez Perce Soil and Water Conservation District (District) and the Nez Perce Tribe Department of Fisheries Resources Management-Watershed (Tribe), in an effort to support the continued existence of these and other aquatic species, have developed this document to direct funding toward priority restoration projects in priority areas for the Big Canyon Creek watershed. In order to achieve this, the District and the Tribe: (1) Developed a working group and technical team composed of managers from a variety of stakeholders within the basin; (2) Established geographically distinct sub-watershed areas called Assessment Units (AUs); (3) Created a prioritization framework for the AUs and prioritized them; and (4) Developed treatment strategies to utilize within the prioritized AUs. Assessment Units were delineated by significant shifts in sampled juvenile O. mykiss (steelhead/rainbow trout) densities, which were found to fall at fish passage barriers. The prioritization framework considered four aspects critical to determining the relative importance of performing restoration in a certain area: density of critical fish species, physical condition of the AU, water quantity, and water quality. It was established, through vigorous data analysis within these four areas, that the geographic priority areas for restoration within the Big Canyon Creek watershed are Big Canyon Creek from stream km 45.5 to the headwaters, Little Canyon from km 15 to 30, the mainstem corridors of Big Canyon (mouth to 7km) and Little Canyon (mouth to 7km). The District and the Tribe

  4. Failure of Tapo Canyon Tailings Dam

    OpenAIRE

    Harder, Leslie F Jr; Stewart, Jonathan P.

    1996-01-01

    The failure of the Tapo Canyon tailings dam was one of the most striking failures of an earth structure to result from the January 17, 1994 Northridge, California earthquake. The failure involved a 60-m-wide breach of a tailings dam with a maximum height of 24 m, and 60 and 90 m downstream displacements of two sections of the dam. The failure resulted from liquefaction of the impounded tailings and possibly of the embankment materials. A significant volume of liquefied tailings passed through...

  5. The Black Canyon of the Gunnison: Today and Yesterday

    Science.gov (United States)

    Hansen, Wallace R.

    1965-01-01

    Since the early visit of Captain John William Gunnison in the middle of the last century, the Black Canyon of the Gunnison has stirred mixed apprehension and wonder in the hearts of its viewers. It ranks high among the more awesome gorges of North America. Many great western canyons are as well remembered for their brightly colored walls as for their airy depths. Not so the Black Canyon. Though it is assuredly not black, the dark-gray tones of its walls and the hazy shadows of its gloomy depths join together to make its name well deserved. Its name conveys an impression, not a picture. After the first emotional impact of the canyon, the same questions come to the minds of most reflective viewers and in about the following order: How deep is the Black Canyon, how wide, how does it compare with other canyons, what are the rocks, how did it form, and how long did it take? Several western canyons exceed the Black Canyon in overall size. Some are longer; some are deeper; some are narrower; and a few have walls as steep. But no other canyon in North American combines the depth, narrowness, sheerness, and somber countenance of the Black Canyon. In many places the Black Canyon is as deep as it is wide. Between The Narrows and Chasm View in the Black Canyon of the Gunnison National Monument (fig. 15) it is much deeper than wide. Average depth in the monument is about 2,000 feet, ranging from a maximum of about 2,700 feet, north of Warner Point (which also is the greatest depth anywhere in the canyon), to a minimum of about 1,750 feet at The Narrows. The stretch of canyon between Pulpit Rock and Chasm View, including The Narrows, though the shallowest in the monument, is also the narrowest, has some of the steepest walls, and is, therefore, among the most impressive segments of the canyon (fig. 3). Profiles of several well-known western canyons are shown in figure 1. Deepest of these by far is Hells Canyon of the Snake, on the Idaho-Oregon border. Clearly, it dwarfs the

  6. Algal and Water-Quality Data for Rapid Creek and Canyon Lake near Rapid City, South Dakota, 2007

    Science.gov (United States)

    Hoogestraat, Galen K.; Putnam, Larry D.; Graham, Jennifer L.

    2008-01-01

    This report summarizes the results of algae and water-quality sampling on Rapid Creek and Canyon Lake during May and September 2007. The overall purpose of the study was to determine the algal community composition of Rapid Creek and Canyon Lake in relation to organisms that are known producers of unwanted tastes and odors in drinking-water supplies. Algal assemblage structure (phytoplankton and periphyton) was examined at 16 sites on Rapid Creek and Canyon Lake during May and September 2007, and actinomycetes bacteria were sampled at the Rapid City water treatment plant intake in May 2007, to determine if taste-and-odor producing organisms were present. During the May 2007 sampling, 3 Rapid Creek sites and 4 Canyon Lake sites were quantitatively sampled for phytoplankton in the water column, 7 Rapid Creek sites were quantitatively sampled for attached periphyton, and 4 lake and retention pond sites were qualitatively sampled for periphyton. Five Rapid Creek sites were sampled for geosmin and 2-methylisoborneol, two common taste-and-odor causing compounds known to affect water supplies. During the September 2007 sampling, 4 Rapid Creek sites were quantitatively sampled for attached periphyton, and 3 Canyon Lake sites were qualitatively sampled for periphyton. Water temperature, dissolved oxygen, pH, and specific conductance were measured during each sampling event. Methods of collection and sample analysis are presented for the various types of biological and chemical constituent samples. Diatoms comprised 91-100 percent of the total algal biovolume in periphyton samples collected during May and September. Cyanobacteria (also called blue-green algae) were detected in 7 of the 11 quantitative periphyton samples and ranged from 0.01 to 2.0 percent of the total biovolume. Cyanobacteria were present in 3 of the 7 phytoplankton samples collected in May, but the relative biovolumes were small (0.01-0.2 percent). Six of seven qualitative samples collected from Canyon Lake

  7. Hanging canyons of Haida Gwaii, British Columbia, Canada: Fault-control on submarine canyon geomorphology along active continental margins

    Science.gov (United States)

    Harris, Peter T.; Barrie, J. Vaughn; Conway, Kim W.; Greene, H. Gary

    2014-06-01

    Faulting commonly influences the geomorphology of submarine canyons that occur on active continental margins. Here, we examine the geomorphology of canyons located on the continental margin off Haida Gwaii, British Columbia, that are truncated on the mid-slope (1200-1400 m water depth) by the Queen Charlotte Fault Zone (QCFZ). The QCFZ is an oblique strike-slip fault zone that has rates of lateral motion of around 50-60 mm/yr and a small convergent component equal to about 3 mm/yr. Slow subduction along the Cascadia Subduction Zone has accreted a prism of marine sediment against the lower slope (1500-3500 m water depth), forming the Queen Charlotte Terrace, which blocks the mouths of submarine canyons formed on the upper slope (200-1400 m water depth). Consequently, canyons along this margin are short (4-8 km in length), closely spaced (around 800 m), and terminate uniformly along the 1400 m isobath, coinciding with the primary fault trend of the QCFZ. Vertical displacement along the fault has resulted in hanging canyons occurring locally. The Haida Gwaii canyons are compared and contrasted with the Sur Canyon system, located to the south of Monterey Bay, California, on a transform margin, which is not blocked by any accretionary prism, and where canyons thus extend to 4000 m depth, across the full breadth of the slope.

  8. PG and E Diablo canyon nuclear power plant, plant information management system, integrated communications system

    International Nuclear Information System (INIS)

    This paper presents the architecture, design and implementation of a plant-wide industrial network for Pacific Gas and Electric Company's (PG and E) Diablo Canyon Nuclear Power Plant (DCPP). The network is referred to as the Integrated Communications System (ICS) and provides a broadband backbone cable plant and communications infrastructure that are capable of reliably carrying data, video, telemetry, image and voice information throughout the plant site. It is used to interconnect 400-800 IBM 3270 PC workstations to the site's numerous computer systems, as well as providing workstation users with several value-added applications

  9. Large wave-shaped bedforms in the axial channel of Monterey Submarine Canyon: Monterey Bay, California

    Science.gov (United States)

    Paull, C. K.; Normark, W. R.; Ussler, W.; Caress, D. W.; Keaten, R.; Barry, J.; Xu, J.; Smith, D.; Covault, J. A.; Maier, K. L.

    2007-12-01

    Multibeam bathymetric data show that large wave-shaped bedforms exist on the seafloor within the axial channel of Monterey Submarine Canyon offshore northern California (Smith et al., 2006). These features have wavelengths up to 70 m, amplitudes up to 2 m, and distinct asymmetrical crests that are roughly perpendicular to the channel. Comparisons of repetitive multibeam surveys since 2004 shows that the bedforms are active features because their positions change between surveys. Three complementary studies are underway to understand the origin of these features: (1) Vibracoring - In June 2007, the ROV Ventana collected 18 vibracores up to 2 m in length along a 130-m transect in ~285 m water depth that spanned the crests of two and the flanks of three waves. Sediment in these cores is composed of one or more sequences of coarse gravel or multicolored clay-clasts that fine upward into sand. Sometimes individual gravel-clasts or clay-chips occur within sand. The internal stratigraphy of these waves shows they resemble classic gravity-flow deposits. (2) Sediment Movement - A pilot study was conducted to assess whether sediment within the canyon floor moves by traction from currents or mass transport. On February 8, 2007, three acoustic beacons were deployed in ~290 m water depth within the canyon axis using Ventana. The beacons were placed within recesses in 50-cm-high ~45 kg poured-concrete monuments. These boulder-sized monuments were buried leaving only the top of the beacon standing ~6 cm above the sediment surface. Thus, the monuments were largely entombed within the seafloor. We also placed 3 acoustic beacons mounted on trapezoidal frames at the edge of a terrace on the canyon's lower flank. On February 12th, we returned to the area and determined that all three monuments had moved ~150 m down canyon. Two trapezoidal frames were found on their sides entwined with each other 50 and 75 m down canyon from their deployment site. The third frame was never located. A

  10. NO2 photolysis frequencies in street canyons

    Directory of Open Access Journals (Sweden)

    E.-P. Roeth

    2010-08-01

    Full Text Available Photolysis frequencies for NO2 are modeled for the conditions in urban streets, which are taken into account as canyons with variable height and width. The effect of a street canyon is presented with absolute values and as a ratio RJ of the photolysis frequency within the street compared to that with free horizon. This allows further use of the existing photolysis parameterizations. Values are presented for variable solar elevation and azimuth angles, varying atmospheric conditions and different street properties. The NO2 photolysis frequency in a street depends strongly on the relative width of the street and its orientation towards the sun. Averaged over atmospheric conditions and street orientation, the NO2 photolysis frequency is reduced in comparison with the values for free horizon: to less than 20% for narrow skyscraper streets, to about 40% for typical urban streets, and only to about 80% for garden streets. A parameterization with the global solar irradiance is given for the averaged RJ values.

  11. Capability to Recover Plutonium-238 in H-Canyon/HB-Line - 13248

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, Kenneth S. Jr.; Smith, Robert H. Jr.; Goergen, Charles R. [Savannah River Nuclear Solutions, LLC, Savannah River Site, Aiken, SC 29802 (United States)

    2013-07-01

    Plutonium-238 is used in Radioisotope Thermoelectric Generators (RTGs) to generate electrical power and in Radioisotope Heater Units (RHUs) to produce heat for electronics and environmental control for deep space missions. The domestic supply of Pu-238 consists of scrap material from previous mission production or material purchased from Russia. Currently, the United States has no significant production scale operational capability to produce and separate new Pu-238 from irradiated neptunium-237 targets. The Department of Energy - Nuclear Energy is currently evaluating and developing plans to reconstitute the United States capability to produce Pu-238 from irradiated Np-237 targets. The Savannah River Site had previously produced and/or processed all the Pu-238 utilized in Radioisotope Thermoelectric Generators (RTGs) for deep space missions up to and including the majority of the plutonium for the Cassini Mission. The previous full production cycle capabilities included: Np- 237 target fabrication, target irradiation, target dissolution and Np-237 and Pu-238 separation and purification, conversion of Np-237 and Pu-238 to oxide, scrap recovery, and Pu-238 encapsulation. The capability and equipment still exist and could be revitalized or put back into service to recover and purify Pu-238/Np-237 or broken General Purpose Heat Source (GPHS) pellets utilizing existing process equipment in HB-Line Scrap Recovery, and H-Canyon Frame Waste Recovery processes. The conversion of Np-237 and Pu-238 to oxide can be performed in the existing HB-Line Phase-2 and Phase- 3 Processes. Dissolution of irradiated Np-237 target material, and separation and purification of Np-237 and Pu-238 product streams would be possible at production rates of ∼2 kg/month of Pu-238 if the existing H-Canyon Frames Process spare equipment were re-installed. Previously, the primary H-Canyon Frames equipment was removed to be replaced: however, the replacement project was stopped. The spare equipment

  12. Late Quaternary vegetation history of Rough Canyon, south-central New Mexico, USA

    Science.gov (United States)

    Betancourt, J.L.; Aasen, Rylander K.; Penalba, C.; McVickar, J.L.

    2001-01-01

    South-central New Mexico, USA, at the junction of the Rocky Mountains, High Plains and Chihuahuan Desert, is one of the better known regions in the late Quaternary of North America. Plant macrofossils and pollen from a packrat midden series in Rough Canyon, New Mexico allows refinement of plant distributions and paleoclimates in this transitional area since full glacial times. From 17000 to 12000 14C yr BP, Pinus edulis-Juniperus scopulorum woodlands dominated limestone substrates between 1800 and 1490 m, with Pseudotsuga menziesii and other mixed-conifer species restricted to shady, north-facing slopes. Juniperus deppeana, the dominant juniper today above 2000 m in southern New Mexico, is conspicuously absent from glacial middens and must have been displaced south of the US-Mexico border. The minimum climatic conditions for P. edulis-J. scopulorum woodlands are ca 20% wetter and 3.5-5??C cooler (July mean maximum temperatures) than the modern climate at Rough Canyon. Holocene warming/drying may have started as early as 12000 14C yr BP with the extirpation of J. scopulorum from Rough Canyon, and was completed by at least 10540 14C yr BP. The record for arrivals of some desert species is confounded by traces of pollen and macrofossils in some of the glacial middens, which could signify either earliest occurrence or temporal mixing (contamination) of assemblages. AMS 14C dating can discriminate between early arrival and contamination in midden macrofossils but not in pollen. AMS dates show that Choisya dumosa, presently near its northern (cold) limits at Rough Canyon, endured late glacial winters, possibly as clonal populations. Some Larrea tridentata leaves and pollen occur in middens dominated by conifers and oaks no longer at the site; an AMS date of 3205 14C yr BP on Larrea leaves from one midden indicates contamination. Evidence for some macrofossil contamination, however, does not rule out the possibility that pollen of desert elements (e.g. Larrea, Prosopis

  13. Aquatic macroinvertebrates and water quality of Sandia Canyon, Los Alamos National Laboratory, November 1993--October 1994

    Energy Technology Data Exchange (ETDEWEB)

    Cross, S.

    1995-08-01

    The Ecological Studies Team (EST) of ESH-20 at Los Alamos National Laboratory (LANL) has collected samples from the stream within Sandia Canyon since the summer of 1990. These field studies gather water quality measurements and collect aquatic macroinvertebrates from permanent sampling sites. Reports by Bennett (1994) and Cross (1994) discuss previous EST aquatic studies in Sandia Canyon. This report updates and expands those findings. EST collected water quality data and aquatic macroinvertebrates at five permanent stations within the canyon from November 1993 through October 1994. The two upstream stations are located below outfalls that discharge industrial and sanitary waste effluent into the stream, thereby maintaining year-round flow. Some water quality parameters are different at the first three stations from those expected of natural streams in the area, indicating degraded water quality due to effluent discharges. The aquatic habitat at the upper stations has also been degraded by sedimentation and channelization. The macroinvertebrate communities at these stations are characterized by low diversities and unstable communities. In contrast, the two downstream stations appear to be in a zone of recovery, where water quality parameters more closely resemble those found in natural streams of the area. The two lower stations have increased macroinvertebrate diversity and stable communities, further indications of downstream water quality improvement.

  14. The C6 Program: Monitoring Climatic Changes in Canyons and Caves Involving Scientific Istitutions, Environmental NGOs and Mountain Sport Associations

    Science.gov (United States)

    di Pietro, R.; Casamento, G.; Interlandi, M.; Madonia, P.

    2007-12-01

    The acronym "C6" means "Climatic Changes and Carbon Cycle in Canyons and Caves". The project was born in 2005, joining under the scientific supervision of the Palermo branch of the Istituto Nazionale di Geofisica e Vulcanologia two different programs both active since 1999; the first was due to the initiative of the Italian Canyoning Association, a no-profit association aimed to the diffusion of the canyoning sport practise in Italy, the second one, developed by the NGO Legambiente Sicilia and funded by the Regione Siciliana-Assessorato Territorio e Ambiente (Sicilian Regional Government, Territorial and Environmental Department), managing the natural reserves of Santa Ninfa, Carburangeli and Sant'Angelo Muxaro caves (Sicily), was focused to verify the existence of a possible environmental negative feedback of human fruition. In 2005 the Royal Society for the Conservation of Nature of Jordan joined the program, and a new site was established inside the Shagher Daghleh Canyon in the Wadi Dana Reserve. In October 2006 the Caver Federation of Bosnia Herzegovina joined the C6 program and another observational site was instituted into a cave close to Sarajevo. Preliminary data acquired indicate how canyons play a very important role in biodiversity preservation in arid and semi-arid environments, whereas caves are extraordinary natural laboratories for the study of carbon dioxide partition between atmosphere and lithosphere, of the effect of rain dynamic on the underground aquifer recharge and, last but not least, of the monitoring of climatic changes. The success of the initiative is based on the very different nature of the co-participants. Caver and canyoning associations guarantee the safe accessibility to difficult environments, like canyons and caves. The selection as measuring sites of natural reserves managed by NGOs, whose activity is essentially based on volunteers, ensure on one hand their environmental stability on a long term perspective, on the other hand

  15. Understanding how gravity flows shape deep-water channels. The Rhone delta canyon (Lake Geneva, Switzerland/France)

    Science.gov (United States)

    Corella, Juan Pablo; Loizeau, Jean Luc; Hilbe, Michael; le Dantec, Nicolas; Sastre, Vincent; Girardclos, Stéphanie

    2014-05-01

    top layer above a stiffer substratum. This soft layer, which increases in thickness towards distal areas, may act as a basal surface for hydroplaning, and might have allowed the debrite to be transported ~9 km away from the source of the scarp failure. The rapid sediment loading, slope undercutting and oversteepening, and increased pore pressure due to high methane concentrations are the main factors for the slope instability and subsequent scarp failure. This study highlights how large mass movements in proximal sites influence the morphology of distal areas by damming the channel and, eventually, forming short-term meanders susceptible to further erosion, as revealed by multibeam bathymetries acquired in AD 2012 in the distal area of the subaquatic canyon.

  16. Remedial Action Plan and Site Design for Stabilization of the Inactive Uranium Mill Tailings Sites at Slick Rock, Colorado: Appendix B to Attachment 3, Lithologic logs and monitor well construction information. Final report

    International Nuclear Information System (INIS)

    This volume contains lithology logs and monitor well construction information for: NC processing site; UC processing site; and Burro Canyon disposal site. This information pertains to the ground water hydrology investigations which is attachment 3 of this series of reports

  17. Floodplain persistence and dynamic-equilibrium conditions in a canyon environment

    Science.gov (United States)

    Tranmer, Andrew W.; Tonina, Daniele; Benjankar, Rohan; Tiedemann, Matthew; Goodwin, Peter

    2015-12-01

    Canyon river systems are laterally constrained by steep walls, strath terraces, and bedrock intrusions; however, semialluvial reaches are nested within these environments as discontinuous floodplains along the river margins. These semialluvial floodplains provide an example of dynamic-equilibrium set within high-energy fluvial systems, marking areas where the river is free to alter its boundary conditions. Most research has focused on hydraulic conditions necessary for floodplain formation and persistence in unconfined systems, whereas little is known about canyon streams. This paper focuses on (1) characterizing dynamic-equilibrium, (2) describing the controls on floodplain formation and distribution, and (3) evaluating the performance of extremal hypotheses to identify dynamic-equilibrium and floodplain persistence in high-energy, semiconfined canyon environments. These objectives were addressed with field and numerical data derived from a one-dimensional hydraulic model for bankfull and 100-year return interval flood events, supported by closely spaced cross sections for the lower 38-km canyon reach of the Deadwood River (Idaho). Under bankfull conditions, critical energy thresholds for equilibrium floodplain persistence at this study site present the upper limits of: slope = 0.018, shear stress = 175 N/m2, and specific stream power = 400 W/m2. Channel and floodplains near equilibrium, quantified with a near-zero sediment transport divergence (Exner equation), were successfully identified by the minimum unit stream power extremal hypothesis and to a lesser degree by the other extremal hypotheses that minimize energy expenditure (minimum specific stream power, minimum total stream power, and minimum Froude number), provided backwater environments and major tributaries could be identified. Extremal results were compared to hydraulic geometry relations to evaluate how closely equilibrium floodplains approached values for unconfined alluvial river systems.

  18. Pollen taphonomy in a canyon stream

    Science.gov (United States)

    Fall, Patricia L.

    1987-11-01

    Surface soil samples from the forested Chuska Mountains to the arid steppe of the Chinle Valley, Northeastern Arizona, show close correlation between modern pollen rain and vegetation. In contrast, modern alluvium is dominated by Pinus pollen throughout the canyon; it reflects neither the surrounding floodplain nor plateau vegetation. Pollen in surface soils is deposited by wind; pollen grains in alluvium are deposited by a stream as sedimentary particles. Clay-size particles correlate significantly with Pinus, Quercus, and Populus pollen. These pollen types settle, as clay does, in slack water. Chenopodiaceae- Amaranthus, Artemisia, other Tubuliflorae, and indeterminate pollen types correlate with sand-size particles, and are deposited by more turbulent water. Fluctuating pollen frequencies in alluvial deposits are related to sedimentology and do not reflect the local or regional vegetation where the sediments were deposited. Alluvial pollen is unreliable for reconstruction of paleoenvironments.

  19. Recent Canyon Heads at the Bosphorus Outlet

    Science.gov (United States)

    Lericolais, G.; Le Drezen, E.; Nouze, H.; Gillet, H.; Ergun, M.; Cific, G.; Avci, M.; Dondurur, D.; Okay, S.

    2002-12-01

    The Black and Marmara Seas have witnessed increased scientific interest in last decade due to improved cooperation between the riparian countries and western scientific institutions but also due to the controversy existing about the origin of the reconnection of the Black Sea and Mediterranean seas after the last Glacial Maximum and its ensuing sea level rise. The Black Sea is linked to the global ocean only through the Bosphorus-Dardanelles system of straits. The Bosphorus is narrow (0.76 to 3.6 km wide) and shallow (32 m) at the sill, restricting the two-way water exchange between the brackish Black Sea and the very saline Mediterranean Sea. The Bosphorus sill was responsible for the behaviour of the Black Sea during the global glaciations and deglaciations, during which the Black Sea level followed the global sea level changes as long as they were higher than the sill. When global sea level was lower than the Bosphorus sill the variations of the Black Sea level reflected specific regional climate conditions without being coupled to the ocean changes. Recent studies suggest that a rapid flooding event may have occurred in the Black Sea during the Holocene. In 1998, a French-Romanian survey collected 4500 km of high-resolution seismic profiles, multibeam bathymetry, and sediment cores on the northern margin of the Black Sea where the shelf is sufficiently wide to preserve ancient shorelines in the vicinity of the shelf edge. If rapid flooding occurred through the Bosphorus Strait to drown these shorelines, it should have created a cataract. In August 2002, the French research vessel "Le Suroit" equipped with a EM 300 multibeam echosounder and a TritonElics Chirp Sonar mapped the Bosphorus outlet at the shelf edge. The results show a large retrogressive canyon deeply incised into the shelf which can be followed landward towards the Bosphorus outlet. Coring on the shelf and in the canyon revealed mega-ripples of shell debris of recent origin.

  20. Nearshore thermal gradients of the Colorado River near the Little Colorado River confluence, Grand Canyon National Park, Arizona, 2010

    Science.gov (United States)

    Ross, Rob; Grams, Paul E.

    2013-01-01

    Construction and operation of Glen Canyon Dam has dramatically impacted the flow of the Colorado River through Glen, Marble, and Grand Canyons. Extremes in both streamflow and water temperature have been suppressed by controlled releases from the dam. Trapping of sediment in Lake Powell, the reservoir formed by Glen Canyon Dam, has also dramatically reduced the supply of suspended sediment entering the system. These changes have altered the riverine ecosystem and the habitat of native species, including fish such as the endangered humpback chub (Gila cypha). Most native fish are adapted to seasonally warm water, and the continuous relatively cold water released by the dam is one of the factors that is believed to limit humpback chub growth and survival. While average mainstem temperatures in the Colorado River are well documented, there is limited understanding of temperatures in the nearshore environments that fish typically occupy. Four nearshore geomorphic unit types were studied between the confluence of the Colorado and Little Colorado Rivers and Lava Canyon in the summer and fall of 2010, for study periods of 10 to 27 days. Five to seven sites were studied during each interval. Persistent thermal gradients greater than the 0.2 °C accuracy of the instruments were not observed in any of the sampled shoreline environments. Temperature gradients between the shoreline and mainstem on the order of 4 °C, believed to be important to the habitat-seeking behavior of native or nonnative fishes, were not detected.

  1. Habitat Mapping Cruise - Hudson Canyon (HB0904, EK60)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Objectives are to: 1) perform multibeam mapping of transitional and deepwater habitats in Hudson Canyon (off New Jersey) with the National Institute of Undersea...

  2. BackscatterC [7125]--Monterey Canyon and Vicinity, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the acoustic-backscatter map of Monterey Canyon and Vicinity map area, California. Backscatter data are provided as separate...

  3. BackscatterB [EM300]--Monterey Canyon and Vicinity, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the acoustic-backscatter map of Monterey Canyon and Vicinity map area, California. Backscatter data are provided as separate...

  4. Ecological-geochemical assessment of soil of the Dniester canyon.

    Directory of Open Access Journals (Sweden)

    Zorin D.O.

    2008-05-01

    Full Text Available An method of calculation of background and anomalous heavy metals, petroleum products and pesticides in soil of the Dniester canyon area for the environmental assessment of the future national park.

  5. Folds--Monterey Canyon and Vicinity Map Area, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the folds for the geologic and geomorphic map of Monterey Canyon and Vicinity, California. The vector data file is included in...

  6. Faults--Monterey Canyon and Vicinity Map Area, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the faults for the geologic and geomorphic map of Monterey Canyon and Vicinity, California. The vector data file is included...

  7. Paleoshorelines--Monterey Canyon and Vicinity Map Area, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the paleoshorelines for the geologic and geomorphic map of Monterey Canyon and Vicinity, California. The vector data file is...

  8. The Trail Inventory of Leslie Canyon NWR [Cycle 2

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of this report is to create a baseline inventory of all non-motorized trails on Leslie Canyon National Wildlife Refuge. Trails in this inventory are...

  9. Establishing a pre-mining geochemical baseline at a uranium mine near Grand Canyon National Park, USA

    Science.gov (United States)

    Naftz, David L.; Walton-Day, Katie

    2016-01-01

    During 2012, approximately 404,000 ha of Federal Land in northern Arizona was withdrawn from consideration of mineral extraction for a 20-year period to protect the Grand Canyon watershed from potentially adverse effects of U mineral exploration and development. The development, operation, and reclamation of the Canyon Mine during the withdrawal period provide an excellent field site to understand and document off-site migration of radionuclides within the withdrawal area. As part of the Department of Interior's (DOI's) study plan for the exclusion area, the objective of our study is to utilize pre-defined decision units (DUs) in areas within and surrounding the Canyon Mine to demonstrate how newly established incremental sampling methodologies (ISM) combined with multivariate statistical methods can be used to document a repeatable and statistically defensible measure of pre-mining baseline conditions in surface soils and stream sediment samples prior to ore extraction. During the survey in June 2013, the highest pre-mining 95% upper confidence level (UCL) concentrations with respect to As, Mo, U, and V were found in the triplicate samples collected from surface soils in the mine site DU designated as M1. Gamma activities were slightly elevated in soils within the M1 DU (up to 28 μR/h); however, off-site gamma activities in soil and stream-sediment samples were lower (national park.

  10. Analysis of dust samples collected from spent nuclear fuel interim storage containers at Hope Creek, Delaware, and Diablo Canyon, California.

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, Charles R.; Enos, David George

    2014-07-01

    Potentially corrosive environments may form on the surface of spent nuclear fuel dry storage canisters by deliquescence of deposited dusts. To assess this, samples of dust were collected from in-service dry storage canisters at two near-marine sites, the Hope Creek and Diablo Canyon storage installations, and have been characterized with respect to mineralogy, chemistry, and texture. At both sites, terrestrially-derived silicate minerals, including quartz, feldspars, micas, and clays, comprise the largest fraction of the dust. Also significant at both sites were particles of iron and iron-chromium metal and oxides generated by the manufacturing process. Soluble salt phases were minor component of the Hope Creek dusts, and were compositionally similar to inland salt aerosols, rich in calcium, sulfate, and nitrate. At Diablo Canyon, however, sea-salt aerosols, occurring as aggregates of NaCl and Mg-sulfate, were a major component of the dust samples. The seasalt aerosols commonly occurred as hollow spheres, which may have formed by evaporation of suspended aerosol seawater droplets, possibly while rising through the heated annulus between the canister and the overpack. The differences in salt composition and abundance for the two sites are attributed to differences in proximity to the open ocean and wave action. The Diablo Canyon facility is on the shores of the Pacific Ocean, while the Hope Creek facility is on the shores of the Delaware River, several miles from the open ocean.

  11. Street canyon ventilation control by proper planning and development

    Directory of Open Access Journals (Sweden)

    Balakin Vladimir Vasil'evich

    2014-05-01

    Full Text Available The objective of street canyon ventilation control in major streets is a tool of air pollution prevention in them, protection of housing areas from excessive wind or preservation and intensification of existing wind speed in case of insufficient ventilation. The maximum permissible concentration of car exhaust pollutants with wind speed within comfortable and permissible values by physiological and hygienic criteria, are ensured as from 40 to 70 % of thoroughfares in major cities. The dependence of air pollution level on wind speed is comparable to its dependence on traffic intensity and ratio of buildings height (H to street width. But one has to take into account that, if the wind blows across the street, vortices form within the street canyon, which results in higher concentration of car exhaust pollutants near the downwind buildings. The objective of this work is to find the functional dependences of wind speed in a major street on its width and density of buildings, and also to find out which street configurations are favorable for formation of closed air circulation within it, resulting in insufficient aeration. The experimental research was done on a site for large-scale modeling of built-up urban territory, using cup anemometers. The coefficients of dependence of wind speed within a street on the types of buildings and on the street width were obtained. Characteristics of street layouts for control of aeration were determined. Building density rates for maximizing or optimizing the wind speed were determined. Street layouts are considered where stable vortices form between the buildings. For example, vortices within the street canyon’s cross-section appear when buildings squarish in ground plan situated far apart are replaced by oblong ones with the minimum allowed intervals of 15 meters between them (for 5-storeyed buildings; or intervals equal to the buildings’ height, or where the buildings are long and close together. With

  12. Diablo Canyon plant information management system and integrated communication system

    Energy Technology Data Exchange (ETDEWEB)

    Stanley, J.W.; Groff, C.

    1990-06-01

    The implementation of a comprehensive maintenance system called the plant information management system (PIMS) at the Diablo Canyon plant, together with its associated integrated communication system (ICS), is widely regarded as the most comprehensive undertaking of its kind in the nuclear industry. This paper provides an overview of the program at Diablo Canyon, an evaluation of system benefits, and highlights the future course of PIMS.

  13. Damming Grand Canyon: The 1923 USGS Colorado River Expedition

    OpenAIRE

    Boyer, Diane E.; Webb, Robert H.

    2007-01-01

    In 1923, America paid close attention, via special radio broadcasts, newspaper headlines, and cover stories in popular magazines, as a government party descended the Colorado to survey Grand Canyon. Fifty years after John Wesley Powell's journey, the canyon still had an aura of mystery and extreme danger. At one point, the party was thought lost in a flood. Something important besides adventure was going on. Led by Claude Birdseye and including colorful characters such as early river-runner E...

  14. Safety Evaluation for Packaging (onsite) T Plant Canyon Items

    Energy Technology Data Exchange (ETDEWEB)

    OBRIEN, J.H.

    2000-07-14

    This safety evaluation for packaging (SEP) evaluates and documents the ability to safely ship mostly unique inventories of miscellaneous T Plant canyon waste items (T-P Items) encountered during the canyon deck clean off campaign. In addition, this SEP addresses contaminated items and material that may be shipped in a strong tight package (STP). The shipments meet the criteria for onsite shipments as specified by Fluor Hanford in HNF-PRO-154, Responsibilities and Procedures for all Hazardous Material Shipments.

  15. Safety Evaluation for Packaging (onsite) T Plant Canyon Items

    International Nuclear Information System (INIS)

    This safety evaluation for packaging (SEP) evaluates and documents the ability to safely ship mostly unique inventories of miscellaneous T Plant canyon waste items (T-P Items) encountered during the canyon deck clean off campaign. In addition, this SEP addresses contaminated items and material that may be shipped in a strong tight package (STP). The shipments meet the criteria for onsite shipments as specified by Fluor Hanford in HNF-PRO-154, Responsibilities and Procedures for all Hazardous Material Shipments

  16. CAPABILITY TO RECOVER PLUTONIUM-238 IN H-CANYON/HB-LINE

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, Kenneth S. Jr.; Smith, Robert H. Jr.; Goergen, Charles R.

    2013-01-09

    Plutonium-238 is used in Radioisotope Thermoelectric Generators (RTGs) to generate electrical power and in Radioisotope Heater Units (RHUs) to produce heat for electronics and environmental control for deep space missions. The domestic supply of Pu-238 consists of scrap material from previous mission production or material purchased from Russia. Currently, the United States has no significant production scale operational capability to produce and separate new Pu-238 from irradiated neptunium-237 targets. The Department of Energy - Nuclear Energy is currently evaluating and developing plans to reconstitute the United States capability to produce Pu-238 from irradiated Np-237 targets. The Savannah River Site had previously produced and/or processed all the Pu-238 utilized in Radioisotope Thermoelectric Generators (RTGs) for deep space missions up to and including the majority of the plutonium for the Cassini Mission. The previous full production cycle capabilities included: Np-237 target fabrication, target irradiation, target dissolution and Np-237 and Pu-238 separation and purification, conversion of Np-237 and Pu-238 to oxide, scrap recovery, and Pu-238 encapsulation. The capability and equipment still exist and could be revitalized or put back into service to recover and purify Pu-238/Np-237 or broken General Purpose Heat Source (GPHS) pellets utilizing existing process equipment in HB-Line Scrap Recovery, and H-anyon Frame Waste Recovery processes. The conversion of Np-237 and Pu-238 to oxide can be performed in the existing HB-Line Phase-2 and Phase-3 Processes. Dissolution of irradiated Np-237 target material, and separation and purification of Np-237 and Pu-238 product streams would be possible at production rates of ~ 2 kg/month of Pu-238 if the existing H-Canyon Frames Process spare equipment were re-installed. Previously, the primary H-Canyon Frames equipment was removed to be replaced: however, the replacement project was stopped. The spare equipment is

  17. Unsaturated Groundwater Flow Beneath Upper Mortandad Canyon, Los Alamos, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Dander, D.C.

    1998-10-15

    Mortandad Canyon is a discharge site for treated industrial effluents containing radionuclides and other chemicals at Los Alamos National Laboratory, New Mexico. This study was conducted to develop an understanding of the unsaturated hydrologic behavior below the canyon floor. The main goal of this study was to evaluate the hypothetical performance of the vadose zone above the water table. Numerical simulations of unsaturated groundwater flow at the site were conducted using the Finite Element Heat and Mass Transfer (FEHM) code. A two-dimensional cross-section along the canyon's axis was used to model flow between an alluvial groundwater system and the regional aquifer approximately 300 m below. Using recharge estimated from a water budget developed in 1967, the simulations showed waters from the perched water table reaching the regional aquifer in 13.8 years, much faster than previously thought. Additionally, simulations indicate that saturation is occurring in the Guaje pumice bed an d that the Tshirege Unit 1B is near saturation. Lithologic boundaries between the eight materials play an important role in flow and solute transport within the system. Horizontal flow is shown to occur in three thin zones above capillary barriers; however, vertical flow dominates the system. Other simulations were conducted to examine the effects of changing system parameters such as varying recharge inputs, varying the distribution of recharge, and bypassing fast-path fractured basalt of uncertain extent and properties. System sensitivity was also explored by changing model parameters with respect to size and types of grids and domains, and the presence of dipping stratigraphy.

  18. Geology of the Hamm Canyon quadrangle, Colorado

    Science.gov (United States)

    Cater, Fred W.

    1953-01-01

    The Hamm Canyon quadrangle is on eof eighteen 7 1/2-minute quadrangles covering the principal carnotite-producing area of southwestern Colorado. The geology of these quadrangles was mapped by the U.S. Geological Survey for the Atomic Energy Commission as part of a comprehensive study of carnotite deposits. The rocks exposed in the eighteen quadrangles consist of crystalline rocks of pre-Cambrian age and sedimentary rocks that range in age from late Paleozoic to Quaternary. Over much of the area the sedimentary rocks are flat lying, but in places the rocks are disrupted by high-angle faults, and northwest-trending folds. Conspicuous among the folds are large anticlines having cores of intrusive salt and gypsum. Most of the carnotite deposits are confined to the Salt Wash sandstone member of the Jurassic Morrison formation. Within this sandstone, most of the deposits are spottily distributed through an arcuate zone known as the "Uravan Mineral Belt". Individual deposits range in size from irregular masses containing only a few tons of ore to large, tabular masses containing many thousands of tons. The ore consists largely of sandstone selectively impregnated and in part replaced by uranium and vanadium minerals. Most of the deposits appear to be related to certain sedimentary structures in sandstones of favorable composition.

  19. Discovery of two new large submarine canyons in the Bering Sea

    Science.gov (United States)

    Carlson, P.R.; Karl, Herman A.

    1984-01-01

    The Beringian continental margin is incised by some of the world's largest submarine canyons. Two newly discovered canyons, St. Matthew and Middle, are hereby added to the roster of Bering Sea canyons. Although these canyons are smaller and not cut back into the Bering shelf like the five very large canyons, they are nonetheless comparable in size to most of the canyons that have been cut into the U.S. eastern continental margin and much larger than the well-known southern California canyons. Both igneous and sedimentary rocks of Eocene to Pliocene age have been dredged from the walls of St. Matthew and Middle Canyons as well as from the walls of several of the other Beringian margin canyons, thus suggesting a late Tertiary to Quaternary genesis of the canyons. We speculate that the ancestral Yukon and possibly Anadyr Rivers were instrumental in initiating the canyon-cutting processes, but that, due to restrictions imposed by island and subsea bedrock barriers, cutting of the two newly discovered canyons may have begun later and been slower than for the other five canyons. ?? 1984.

  20. Variability in rainfall at monitoring stations and derivation of a long-term rainfall intensity record in the Grand Canyon Region, Arizona, USA

    Science.gov (United States)

    Caster, Joshua; Sankey, Joel B.

    2016-04-11

    In this study, we examine rainfall datasets of varying temporal length, resolution, and spatial distribution to characterize rainfall depth, intensity, and seasonality for monitoring stations along the Colorado River within Marble and Grand Canyons. We identify maximum separation distances between stations at which rainfall measurements might be most useful for inferring rainfall characteristics at other locations. We demonstrate a method for applying relations between daily rainfall depth and intensity, from short-term high-resolution data to lower-resolution longer-term data, to synthesize a long-term record of daily rainfall intensity from 1950–2012. We consider the implications of our spatio-temporal characterization of rainfall for understanding local landscape change in sedimentary deposits and archaeological sites, and for better characterizing past and present rainfall and its potential role in overland flow erosion within the canyons. We find that rainfall measured at stations within the river corridor is spatially correlated at separation distances of tens of kilometers, and is not correlated at the large elevation differences that separate stations along the Colorado River from stations above the canyon rim. These results provide guidance for reasonable separation distances at which rainfall measurements at stations within the Grand Canyon region might be used to infer rainfall at other nearby locations along the river. Like other rugged landscapes, spatial variability between rainfall measured at monitoring stations appears to be influenced by canyon and rim physiography and elevation, with preliminary results suggesting the highest elevation landform in the region, the Kaibab Plateau, may function as an important orographic influence. Stations at specific locations within the canyons and along the river, such as in southern (lower) Marble Canyon and eastern (upper) Grand Canyon, appear to have strong potential to receive high-intensity rainfall that

  1. Survey of plutonium and uranium atom ratios and activity levels in Mortandad Canyon

    Energy Technology Data Exchange (ETDEWEB)

    Gallaher, B.M.; Benjamin, T.M.; Rokop, D.J.; Stoker, A.K.

    1997-09-22

    For more than three decades Mortandad Canyon has been the primary release area of treated liquid radioactive waste from the Los Alamos National Laboratory (Laboratory). In this survey, six water samples and seven stream sediment samples collected in Mortandad Canyon were analyzed by thermal ionization mass spectrometry (TIMS) to determine the plutonium and uranium activity levels and atom ratios. Be measuring the {sup 240}Pu/{sup 239}Pu atom ratios, the Laboratory plutonium component was evaluated relative to that from global fallout. Measurements of the relative abundance of {sup 235}U and {sup 236}U were also used to identify non-natural components. The survey results indicate the Laboratory plutonium and uranium concentrations in waters and sediments decrease relatively rapidly with distance downstream from the major industrial sources. Plutonium concentrations in shallow alluvial groundwater decrease by approximately 1000 fold along a 3000 ft distance. At the Laboratory downstream boundary, total plutonium and uranium concentrations were generally within regional background ranges previously reported. Laboratory derived plutonium is readily distinguished from global fallout in on-site waters and sediments. The isotopic ratio data indicates off-site migration of trace levels of Laboratory plutonium in stream sediments to distances approximately two miles downstream of the Laboratory boundary.

  2. Influence of topographic complexity on solar insolation estimates for the Colorado River, Grand Canyon, AZ

    Science.gov (United States)

    Yard, M.D.; Bennett, G.E.; Mietz, S.N.; Coggins, L.G., Jr.; Stevens, L.E.; Hueftle, S.; Blinn, D.W.

    2005-01-01

    Rugged topography along the Colorado River in Glen and Grand Canyons, exemplifies features common to canyon-bound streams and rivers of the arid southwest. Physical relief influences regulated river systems, especially those that are altered, and have become partially reliant on aquatic primary production. We measured and modeled instantaneous solar flux in a topographically complex environment to determine where differences in daily, seasonal and annual solar insolation occurred in this river system. At a system-wide scale, topographic complexity generates a spatial and temporal mosaic of varying solar insolation. This solar variation is a predictable consequence of channel orientation, geomorphology, elevation angles and viewshed. Modeled estimates for clear conditions corresponded closely with observed measurements for both instantaneous photosynthetic photon flux density (PPFD: ??mol m-2 s-1) and daily insolation levels (relative error 2.3%, CI ??0.45, S.D. 0.3, n = 29,813). Mean annual daily insolation levels system-wide were estimated to be 36 mol m-2 d -1 (17.5 S.D.), and seasonally varied on average from 13.4-57.4 mol m-2 d-1, for winter and summer, respectively. In comparison to identical areas lacking topographic effect (idealized plane), mean daily insolation levels were reduced by 22% during summer, and as much as 53% during winter. Depending on outlying topography, canyon bound regions having east-west (EW) orientations had higher seasonal variation, averaging from 8.1 to 61.4 mol m-2 d-1, for winter and summer, respectively. For EW orientations, 70% of mid-channel sites were obscured from direct incidence during part of the year; and of these sites, average diffuse light conditions persisted for 19.3% of the year (70.5 days), and extended upwards to 194 days. This predictive model has provided an initial quantitative step to estimate and determine the importance of autotrophic production for this ecosystem, as well as a broader application for other

  3. Spatial Vegetation Data for Canyon De Chelly National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The Canyon de Chelly National Monument Vegetation Map Database was developed as a primary product in the Canyon de Chelly National Monument Vegetation...

  4. Software Configuration Management Plan for the B-Plant Canyon Ventilation Control System

    Energy Technology Data Exchange (ETDEWEB)

    MCDANIEL, K.S.

    1999-08-31

    Project W-059 installed a new B Plant Canyon Ventilation System. Monitoring and control of the system is implemented by the Canyon Ventilation Control System (CVCS). This Software Configuration Management Plan provides instructions for change control of the CVCS.

  5. 76 FR 22670 - Black Hills National Forest, Hell Canyon Ranger District, South Dakota, Vestal Project

    Science.gov (United States)

    2011-04-22

    ... Forest Service Black Hills National Forest, Hell Canyon Ranger District, South Dakota, Vestal Project..., District Ranger, Black Hills National Forest, Hell Canyon Ranger District, 330 Mount Rushmore Road, Custer, South Dakota 57730. Telephone Number: (605) 673- 4853. E-mail:...

  6. Samples from the Georges Bank Canyons acquired in 1936 (STETSON36 shapefile)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Submarine canyons cut into the edge of the continental shelf and the continental slope along much of the U.S. Atlantic coast. Three canyons along the southern edge...

  7. 2011 Pacific Gas and Electric Diablo Canyon Power Plant (DCPP): Los Osos, CA Central Coast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Diablo Canyon Power Plant (DCPP) LiDAR and Imagery datasets are comprised of three separate LiDAR surveys: Diablo Canyon (2010), Los Osos (2011), and San Simeon...

  8. 2013 Pacific Gas and Electric Diablo Canyon Power Plant (DCPP): San Simeon, CA Central Coast

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Diablo Canyon Power Plant (DCPP) LiDAR and Imagery datasets are comprised of three separate LiDAR surveys: Diablo Canyon (2010), Los Osos (2011), and San Simeon...

  9. Data from Oceanographer, Lydonia, and Gilbert Canyons acquired in 1965 (SCHWARTZ65 shapefile)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Submarine canyons occur at the edge of the continental shelf and cut across the slope and rise along the U.S. east coast. Three of these canyons (Oceanographer,...

  10. Digital geologic map of the Thirsty Canyon NW quadrangle, Nye County, Nevada

    Science.gov (United States)

    Minor, S.A.; Orkild, P.P.; Sargent, K.A.; Warren, R.G.; Sawyer, D.A.; Workman, J.B.

    1998-01-01

    This digital geologic map compilation presents new polygon (i.e., geologic map unit contacts), line (i.e., fault, fold axis, dike, and caldera wall), and point (i.e., structural attitude) vector data for the Thirsty Canyon NW 7 1/2' quadrangle in southern Nevada. The map database, which is at 1:24,000-scale resolution, provides geologic coverage of an area of current hydrogeologic and tectonic interest. The Thirsty Canyon NW quadrangle is located in southern Nye County about 20 km west of the Nevada Test Site (NTS) and 30 km north of the town of Beatty. The map area is underlain by extensive layers of Neogene (about 14 to 4.5 million years old [Ma]) mafic and silicic volcanic rocks that are temporally and spatially associated with transtensional tectonic deformation. Mapped volcanic features include part of a late Miocene (about 9.2 Ma) collapse caldera, a Pliocene (about 4.5 Ma) shield volcano, and two Pleistocene (about 0.3 Ma) cinder cones. Also documented are numerous normal, oblique-slip, and strike-slip faults that reflect regional transtensional deformation along the southern part of the Walker Lane belt. The Thirsty Canyon NW map provides new geologic information for modeling groundwater flow paths that may enter the map area from underground nuclear testing areas located in the NTS about 25 km to the east. The geologic map database comprises six component ArcINFO map coverages that can be accessed after decompressing and unbundling the data archive file (tcnw.tar.gz). These six coverages (tcnwpoly, tcnwflt, tcnwfold, tcnwdike, tcnwcald, and tcnwatt) are formatted here in ArcINFO EXPORT format. Bundled with this database are two PDF files for readily viewing and printing the map, accessory graphics, and a description of map units and compilation methods.

  11. Macro- and megafauna recorded in the submarine Bari Canyon (southern Adriatic, Mediterranean Sea using different tools

    Directory of Open Access Journals (Sweden)

    G. D'ONGHIA

    2015-01-01

    Full Text Available Macro- and megafauna were recorded in the submarine Bari Canyon (southern Adriatic Sea, Mediterranean Sea during an oceanographic cruise carried out in May-June 2012 and an experimental fishing survey conducted in November 2013. During the former, a total of 20 benthic samples were taken using a Van Veen grab at depths between 268 and 770 m and 4 deployments of a baited lander, for about 43 hours of video records, were carried out at depths between 443 and 788 m. During the latter, 8 longline fishing operations were conducted from 338 down to 612 m. Eighty-five living benthic and benthopelagic species were recorded: 29 Porifera, 1 Cnidaria, 2 Mollusca, 11 Annelida, 1 Arthropoda, 19 Bryozoa, 3 Echinodermata and 19 Chordata. A total of 51 species are new records for the Bari Canyon, 29 new records for the Adriatic Sea. Among the Porifera Cerbaris curvispiculifer is a new addition for the Italian Sponge Fauna. The first certain record of living specimens for the bryozoan Crisia tenella longinodata is reported. A total of 6 Mediterranean endemic species have been identified: 4 Porifera and 2 Annelida. The bathymetric range of some species has been extended. New information acquired for deep sea species confirms their importance in the structure of cold-water coral communities. This study has updated the knowledge on the biodiversity of the Adriatic Sea, as well as of the Bari Canyon in particular, one of the sites designated as “jewels of the Mediterranean” for which urgent conservation measures are needed.

  12. Regional economic impacts of Grand Canyon river runners.

    Science.gov (United States)

    Hjerpe, Evan E; Kim, Yeon-Su

    2007-10-01

    Economic impact analysis (EIA) of outdoor recreation can provide critical social information concerning the utilization of natural resources. Outdoor recreation and other non-consumptive uses of resources are viewed as environmentally friendly alternatives to extractive-type industries. While outdoor recreation can be an appropriate use of resources, it generates both beneficial and adverse socioeconomic impacts on rural communities. The authors used EIA to assess the regional economic impacts of rafting in Grand Canyon National Park. The Grand Canyon region of northern Arizona represents a rural US economy that is highly dependent upon tourism and recreational expenditures. The purpose of this research is twofold. The first is to ascertain the previously unknown regional economic impacts of Grand Canyon river runners. The second purpose is to examine attributes of these economic impacts in terms of regional multipliers, leakage, and types of employment created. Most of the literature on economic impacts of outdoor recreation has focused strictly on the positive economic impacts, failing to illuminate the coinciding adverse and constraining economic impacts. Examining the attributes of economic impacts can highlight deficiencies and constraints that limit the economic benefits of recreation and tourism. Regional expenditure information was obtained by surveying non-commercial boaters and commercial outfitters. The authors used IMPLAN input-output modeling to assess direct, indirect, and induced effects of Grand Canyon river runners. Multipliers were calculated for output, employment, and income. Over 22,000 people rafted on the Colorado River through Grand Canyon National Park in 2001, resulting in an estimated $21,100,000 of regional expenditures to the greater Grand Canyon economy. However, over 50% of all rafting-related expenditures were not captured by the regional economy and many of the jobs created by the rafting industry are lower-wage and seasonal. Policy

  13. 76 FR 54487 - Charter Renewal, Glen Canyon Dam Adaptive Management Work Group

    Science.gov (United States)

    2011-09-01

    ... Bureau of Reclamation Charter Renewal, Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of... the Glen Canyon Dam Adaptive Management Work Group. The purpose of the Adaptive Management Work Group... of the Glen Canyon Dam Adaptive Management Work Group is in the public interest in connection...

  14. 78 FR 54482 - Charter Renewal, Glen Canyon Dam Adaptive Management Work Group

    Science.gov (United States)

    2013-09-04

    ... Bureau of Reclamation Charter Renewal, Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of... the Glen Canyon Dam Adaptive Management Work Group. The purpose of the Adaptive Management Work Group... Canyon Dam Adaptive Management Work Group is in the public interest in connection with the performance...

  15. Marine geophysical investigations across the submarine canyon (Swatch-of-No-Ground), northern Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Subrahmanyam, V.; Krishna, K.S.; Ramana, M.V.; Murthy, K.S.R.

    ., the morphology of the canyon is vice versa. The anatomy of the canyon suggests that the turbidity sediments flow in a semi-circular manner within it. When the muddy sediments strike the flank within the canyon, a part gets bounced-off in an orthogonal direction...

  16. Review of the Diablo Canyon probabilistic risk assessment

    Energy Technology Data Exchange (ETDEWEB)

    Bozoki, G.E.; Fitzpatrick, R.G.; Bohn, M.P. [Sandia National Lab., Albuquerque, NM (United States); Sabek, M.G. [Atomic Energy Authority, Nuclear Regulatory and Safety Center, Cairo (Egypt); Ravindra, M.K.; Johnson, J.J. [EQE Engineering, San Francisco, CA (United States)

    1994-08-01

    This report details the review of the Diablo Canyon Probabilistic Risk Assessment (DCPRA). The study was performed under contract from the Probabilistic Risk Analysis Branch, Office of Nuclear Reactor Research, USNRC by Brookhaven National Laboratory. The DCPRA is a full scope Level I effort and although the review touched on all aspects of the PRA, the internal events and seismic events received the vast majority of the review effort. The report includes a number of independent systems analyses sensitivity studies, importance analyses as well as conclusions on the adequacy of the DCPRA for use in the Diablo Canyon Long Term Seismic Program.

  17. Thermopower signatures and spectroscopy of the canyon of conductance suppression

    Science.gov (United States)

    Kiršanskas, G.; Hammarberg, S.; Karlström, O.; Wacker, A.

    2016-07-01

    Interference effects in quantum dots between different transport channels can lead to a strong suppression of conductance, which cuts like a canyon through the common conductance plot [Phys. Rev. Lett. 104, 186804 (2010), 10.1103/PhysRevLett.104.186804]. In the present work we consider the thermoelectric transport properties of the canyon of conductance suppression using the second-order von Neumann approach. We observe a characteristic signal for the zeros of the thermopower. This demonstrates that thermoelectric measurements are an interesting complimentary tool to study complex phenomena for transport through confined systems.

  18. Sediment Transport During Three Controlled-Flood Experiments on the Colorado River Downstream from Glen Canyon Dam, with Implications for Eddy-Sandbar Deposition in Grand Canyon National Park

    Science.gov (United States)

    Topping, David J.; Rubin, David M.; Grams, Paul E.; Griffiths, Ronald E.; Sabol, Thomas A.; Voichick, Nicholas; Tusso, Robert B.; Vanaman, Karen M.; McDonald, Richard R.

    2010-01-01

    Three large-scale field experiments were conducted on the Colorado River downstream from Glen Canyon Dam in 1996, 2004, and 2008 to evaluate whether artificial (that is, controlled) floods released from the dam could be used in conjunction with the sand supplied by downstream tributaries to rebuild and sustainably maintain eddy sandbars in the river in Grand Canyon National Park. Higher suspended-sand concentrations during a controlled flood will lead to greater eddy-sandbar deposition rates. During each controlled flood experiment, sediment-transport and bed-sediment data were collected to evaluate sediment-supply effects on sandbar deposition. Data collection substantially increased in spatial and temporal density with each subsequent experiment. The suspended- and bed-sediment data collected during all three controlled-flood experiments are presented and analyzed in this report. Analysis of these data indicate that in designing the hydrograph of a controlled flood that is optimized for sandbar deposition in a given reach of the Colorado River, both the magnitude and the grain size of the sand supply must be considered. Because of the opposing physical effects of bed-sand area and bed-sand grain size in regulating suspended-sand concentration, larger amounts of coarser sand on the bed can lead to lower suspended-sand concentrations, and thus lower rates of sandbar deposition, during a controlled flood than can lesser amounts of finer sand on the bed. Although suspended-sand concentrations were higher at all study sites during the 2008 controlled-flood experiment (CFE) than during either the 1996 or 2004 CFEs, these higher concentrations were likely associated with more sand on the bed of the Colorado River in only lower Glen Canyon. More sand was likely present on the bed of the river in Grand Canyon during the 1996 CFE than during either the 2004 or 2008 CFEs. The question still remains as to whether sandbars can be sustained in the Colorado River in Grand

  19. Submarine canyons as important habitat for cetaceans, with special reference to the Gully: A review

    Science.gov (United States)

    Moors-Murphy, Hilary B.

    2014-06-01

    There has been much research interest in the use of submarine canyons by cetaceans, particularly beaked whales (family Ziphiidae), which appear to be especially attracted to canyon habitats in some areas. However, not all submarine canyons are associated with large numbers of cetaceans and the mechanisms through which submarine canyons may attract cetaceans are not clearly understood. This paper reviews some of the cetacean associations with submarine canyons that have been anecdotally described or presented in scientific literature and discusses the physical, oceanographic and biological mechanisms that may lead to enhanced cetacean abundance around these canyons. Particular attention is paid to the Gully, a large submarine canyon and Marine Protected Area off eastern Canada for which there exists some of the strongest evidence available for submarine canyons as important cetacean habitat. Studies demonstrating increased cetacean abundance in the Gully and the processes that are likely to attract cetaceans to this relatively well-studied canyon are discussed. This review provides some limited evidence that cetaceans are more likely to associate with larger canyons; however, further studies are needed to fully understand the relationship between the physical characteristics of canyons and enhanced cetacean abundance. In general, toothed whales (especially beaked whales and sperm whales) appear to exhibit the strongest associations with submarine canyons, occurring in these features throughout the year and likely attracted by concentrating and aggregating processes. By contrast, baleen whales tend to occur in canyons seasonally and are most likely attracted to canyons by enrichment and concentrating processes. Existing evidence thus suggests that at least some submarine canyons are important foraging areas for cetaceans, and should be given special consideration for cetacean conservation and protection.

  20. Rock fall simulation at Timpanogos Cave National Monument, American Fork Canyon, Utah, USA

    Science.gov (United States)

    Harp, Edwin L.; Dart, Richard L.; Reichenbach, Paola

    2011-01-01

    Rock fall from limestone cliffs at Timpanogos Cave National Monument in American Fork Canyon east of Provo, Utah, is a common occurrence. The cave is located in limestone cliffs high on the southern side of the canyon. One fatality in 1933 led to the construction of rock fall shelters at the cave entrance and exit in 1976. Numerous rock fall incidents, including a near miss in 2000 in the vicinity of the trail below the cave exit, have led to a decision to extend the shelter at the cave exit to protect visitors from these ongoing rock fall events initiating from cliffs immediately above the cave exit. Three-dimensional rock fall simulations from sources at the top of these cliffs have provided data from which to assess the spatial frequencies and velocities of rock falls from the cliffs and to constrain the design of protective measures to reduce the rock fall hazard. Results from the rock fall simulations are consistent with the spatial patterns of rock fall impacts that have been observed at the cave exit site.

  1. 36 CFR 7.92 - Bighorn Canyon National Recreation Area.

    Science.gov (United States)

    2010-07-01

    ... Recreation Area. 7.92 Section 7.92 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF... Recreation Area. (a) Aircraft-designated airstrip. (1) Fort Smith landing strip, located at approximate... Canyon National Recreation Area, except in the following areas: (i) In the gated area south of...

  2. Carbonaceous aerosol particles from common vegetation in the Grand Canyon

    Energy Technology Data Exchange (ETDEWEB)

    Hallock, K.A.; Mazurek, M.A. (Brookhaven National Lab., Upton, NY (United States)); Cass, G.R. (California Inst. of Tech., Pasadena, CA (United States). Dept. of Environmental Engineering Science)

    1992-05-01

    The problem of visibility reduction in the Grand Canyon due to fine organic aerosol particles in the atmosphere has become an area of increased environmental concern. Aerosol particles can be derived from many emission sources. In this report, we focus on identifying organic aerosols derived from common vegetation in the Grand Canyon. These aerosols are expected to be significant contributors to the total atmospheric organic aerosol content. Aerosol samples from living vegetation were collected by resuspension of surface wax and resin components liberated from the leaves of vegetation common to areas of the Grand Canyon. The samples were analyzed using high-resolution gas chromatography/mass spectrometry (GC/MS). Probable identification of compounds was made by comparison of sample spectra with National Institute of Standards and Technology (NIST) mass spectral references and positive identification of compounds was made when possible by comparison with authentic standards as well as NIST references. Using these references, we have been able to positively identify the presence of n-alkane and n-alkanoic acid homolog series in the surface waxes of the vegetation sampled. Several monoterpenes, sesquiterpenes, and diterpenes were identified also as possible biogenic aerosols which may contribute to the total organic aerosol abundance leading to visibility reduction in the Grand Canyon.

  3. Carbonaceous aerosol particles from common vegetation in the Grand Canyon

    International Nuclear Information System (INIS)

    The problem of visibility reduction in the Grand Canyon due to fine organic aerosol particles in the atmosphere has become an area of increased environmental concern. Aerosol particles can be derived from many emission sources. In this report, we focus on identifying organic aerosols derived from common vegetation in the Grand Canyon. These aerosols are expected to be significant contributors to the total atmospheric organic aerosol content. Aerosol samples from living vegetation were collected by resuspension of surface wax and resin components liberated from the leaves of vegetation common to areas of the Grand Canyon. The samples were analyzed using high-resolution gas chromatography/mass spectrometry (GC/MS). Probable identification of compounds was made by comparison of sample spectra with National Institute of Standards and Technology (NIST) mass spectral references and positive identification of compounds was made when possible by comparison with authentic standards as well as NIST references. Using these references, we have been able to positively identify the presence of n-alkane and n-alkanoic acid homolog series in the surface waxes of the vegetation sampled. Several monoterpenes, sesquiterpenes, and diterpenes were identified also as possible biogenic aerosols which may contribute to the total organic aerosol abundance leading to visibility reduction in the Grand Canyon

  4. Submarine canyons as coral and sponge habitat on the eastern Bering Sea slope

    Directory of Open Access Journals (Sweden)

    Robert J. Miller

    2015-07-01

    Full Text Available Submarine canyons have been shown to positively influence pelagic and benthic biodiversity and ecosystem function. In the eastern Bering Sea, several immense canyons lie under the highly productive “green belt” along the continental slope. Two of these, Pribilof and Zhemchug canyons, are the focus of current conservation interest. We used a maximum entropy modeling approach to evaluate the importance of these two canyons, as well as canyons in general, as habitat for gorgonian (alcyonacean corals, pennatulacean corals, and sponges, in an area comprising most of the eastern Bering Sea slope and outer shelf. These invertebrates create physical structure that is a preferred habitat for many mobile species, including commercially important fish and invertebrates. We show that Pribilof canyon is a hotspot of structure-forming invertebrate habitat, containing over 50% of estimated high-quality gorgonian habitat and 45% of sponge habitat, despite making up only 1.7% of the total study area. The amount of quality habitat for gorgonians and sponges varied in other canyons, but canyons overall contained more high-quality habitat for structure-forming invertebrates compared to other slope areas. Bottom trawling effort was not well correlated with habitat quality for structure-forming invertebrates, and bottom-contact fishing effort in general, including longlining and trawling, was not particularly concentrated in the canyons examined. These results suggest that if conserving gorgonian coral habitat is a management goal, canyons, particularly Pribilof Canyon, may be a prime location to do this without excessive impact on fisheries.

  5. Canyons and gorges as potential geotourism destinations in Serbia: comparative analysis from two perspectives - general geotourists' and pure geotourists'

    Science.gov (United States)

    Božić, Sanja; Tomić, Nemanja

    2015-10-01

    Serbia represents one of those countries which have not yet differentiated themselves on the world tourism map. However, it has an immense but still unrevealed potential for geotourism development. In this paper we analyzed several remarkable canyons and gorges of great scientific importance and geotourism potential. These sites include the Djerdap Gorge and Lazar River Canyon, located in Eastern Serbia and the Ovcar-Kablar Gorge and Uvac Canyon located in Western Serbia. One of the main goals of this paper was to analyze and compare the current state and tourism potential of these geosites by using the M-GAM model for geosite assessment. However, the principal aim of the paper is to analyze how important is each subindicator in the assessment process for different market segments. In this paper, we also analyzed how giving different importance to subindicators can influence the position of the geosites in the matrix indicating different assessment done by two chosen market segments. The research showed that general geotourists appreciate considerably different values when assessing a geosite in comparison to pure geotourists. The paper can be used as framework for developing the tourism management strategy of geosites taking into consideration the needs and preferences of the target market segments.

  6. Methane Flux and Authigenic Carbonate in Shallow Sediments Overlying Methane Hydrate Bearing Strata in Alaminos Canyon, Gulf of Mexico

    Directory of Open Access Journals (Sweden)

    Joseph P. Smith

    2014-09-01

    Full Text Available In June 2007 sediment cores were collected in Alaminos Canyon, Gulf of Mexico across a series of seismic data profiles indicating rapid transitions between the presence of methane hydrates and vertical gas flux. Vertical profiles of dissolved sulfate, chloride, calcium, magnesium, and dissolved inorganic carbon (DIC concentrations in porewaters, headspace methane, and solid phase carbonate concentrations were measured at each core location to investigate the cycling of methane-derived carbon in shallow sediments overlying the hydrate bearing strata. When integrated with stable carbon isotope ratios of DIC, geochemical results suggest a significant fraction of the methane flux at this site is cycled into the inorganic carbon pool. The incorporation of methane-derived carbon into dissolved and solid inorganic carbon phases represents a significant sink in local carbon cycling and plays a role in regulating the flux of methane to the overlying water column at Alaminos Canyon. Targeted, high-resolution geochemical characterization of the biogeochemical cycling of methane-derived carbon in shallow sediments overlying hydrate bearing strata like those in Alaminos Canyon is critical to quantifying methane flux and estimating methane hydrate distributions in gas hydrate bearing marine sediments.

  7. Aquatic macroinvertebrates and water quality of Sandia Canyon, Los Alamos National Laboratory, December 1992--October 1993. Status report

    International Nuclear Information System (INIS)

    In the summer of 1990, an accidental spill from the TA-3 Power Plant Environment Tank released more than 3,785 liters of sulfuric acid into upper Sandia Canyon. The Biological Resource Evaluation Team (BRET) of EM-8 at Los Alamos National Laboratory (LANL) has collected aquatic samples from the stream within Sandia Canyon since then. These field studies gather water quality measurements and collect macroinvertebrates from permanent sampling sites. An earlier report by Bennett (1994) discusses previous BRET aquatic studies in Sandia Canyon. This report updates and expands Bennett's initial findings. During 1993, BRET collected water quality data and aquatic macroinvertebrates at five permanent stations within the canyon. The substrates of the upper three stations are largely sands and silts while the substrates of the two lower stations are largely rock and cobbles. The two upstream stations are located near outfalls that discharge industrial and sanitary waste effluent. The third station is within a natural cattail marsh, approximately 0.4 km (0.25 mi) downstream from Stations SC1 and SC2. Water quality parameters are slightly different at these first three stations from those expected of natural streams, suggesting slightly degraded water quality. Correspondingly, the macroinvertebrate communities at these stations are characterized by low diversities and poorly-developed community structures. The two downstream stations appear to be in a zone of recovery, where water quality parameters more closely resemble those found in natural streams of the area. Macroinvertebrate diversity increases and community structure becomes more complex at the two lower stations, which are further indications of improved water quality downstream

  8. Aquatic macroinvertebrates and water quality of Sandia Canyon, Los Alamos National Laboratory, December 1992--October 1993. Status report

    Energy Technology Data Exchange (ETDEWEB)

    Cross, S. [Ewing Technical Design, Inc., Albuquerque, NM (United States)

    1994-09-01

    In the summer of 1990, an accidental spill from the TA-3 Power Plant Environment Tank released more than 3,785 liters of sulfuric acid into upper Sandia Canyon. The Biological Resource Evaluation Team (BRET) of EM-8 at Los Alamos National Laboratory (LANL) has collected aquatic samples from the stream within Sandia Canyon since then. These field studies gather water quality measurements and collect macroinvertebrates from permanent sampling sites. An earlier report by Bennett (1994) discusses previous BRET aquatic studies in Sandia Canyon. This report updates and expands Bennett`s initial findings. During 1993, BRET collected water quality data and aquatic macroinvertebrates at five permanent stations within the canyon. The substrates of the upper three stations are largely sands and silts while the substrates of the two lower stations are largely rock and cobbles. The two upstream stations are located near outfalls that discharge industrial and sanitary waste effluent. The third station is within a natural cattail marsh, approximately 0.4 km (0.25 mi) downstream from Stations SC1 and SC2. Water quality parameters are slightly different at these first three stations from those expected of natural streams, suggesting slightly degraded water quality. Correspondingly, the macroinvertebrate communities at these stations are characterized by low diversities and poorly-developed community structures. The two downstream stations appear to be in a zone of recovery, where water quality parameters more closely resemble those found in natural streams of the area. Macroinvertebrate diversity increases and community structure becomes more complex at the two lower stations, which are further indications of improved water quality downstream.

  9. Thermal bioclimate in idealized urban street canyons in Campinas, Brazil

    Science.gov (United States)

    Abreu-Harbich, Loyde V.; Labaki, Lucila C.; Matzarakis, Andreas

    2014-01-01

    Among several urban design parameters, the height-to-width ratio (H/W) and orientation are important parameters strongly affecting thermal conditions in cities. This paper quantifies changes in thermal comfort due to typical urban canyon configurations in Campinas, Brazil, and presents urban guidelines concerning H/W ratios and green spaces to adapt urban climate change. The study focuses on thermal comfort issues of humans in urban areas and performs evaluation in terms of physiologically equivalent temperature (PET), based on long-term data. Meteorological data of air temperature, relative humidity, wind speed and solar radiation over a 7-year period (2003-2010) were used. A 3D street canyon model was designed with RayMan Pro software to simulate the influence of urban configuration on urban thermal climate. The following configurations and setups were used. The model canyon was 500 m in length, with widths 9, 21, and 44 m. Its height varied in steps of 2.5 m, from 5 to 40 m. The canyon could be rotated in steps of 15°. The results show that urban design parameters such as width, height, and orientation modify thermal conditions within street canyons. A northeast-southwest orientation can reduce PET during daytime more than other scenarios. Forestry management and green areas are recommended to promote shade on pedestrian areas and on façades, and to improve bioclimate thermal stress, in particular for H/W ratio less than 0.5. The method and results can be applied by architects and urban planners interested in developing responsive guidelines for urban climate issues.

  10. Fall Chinook Acclimation Project; Pittsburg Landing, Captain John Rapids, and Big Canyon, Annual Report 2003.

    Energy Technology Data Exchange (ETDEWEB)

    McLeod, Bruce

    2004-01-01

    Fisheries co-managers of U.S. v Oregon supported and directed the construction and operation of acclimation and release facilities for Snake River fall Chinook from Lyons Ferry Hatchery at three sites above Lower Granite Dam. In 1996, Congress instructed the U.S. Army Corps of Engineers (USCOE) to construct, under the Lower Snake River Compensation Plan (LSRCP), final rearing and acclimation facilities for fall Chinook in the Snake River basin to complement their activities and efforts in compensating for fish lost due to construction of the lower Snake River dams. The Nez Perce Tribe (NPT) played a key role in securing funding and selecting acclimation sites, then assumed responsibility for operation and maintenance of the facilities. In 1997, Bonneville Power Administrative (BPA) was directed to fund operations and maintenance (O&M) for the facilities. Two acclimation facilities, Captain John Rapids and Pittsburg Landing, were located on the Snake River between Asotin, WA and Hells Canyon Dam and one facility, Big Canyon, was located on the Clearwater River at Peck. The Capt. John Rapids facility is a single pond while the Pittsburg Landing and Big Canyon sites consist of portable fish rearing tanks assembled and disassembled each year. Acclimation of 450,000 yearling smolts (150,000 each facility) begins in March and ends 6 weeks later. When available, an additional 2,400,000 fall Chinook sub-yearlings may be acclimated for 6 weeks, following the smolt release. The project goal is to increase the naturally spawning population of Snake River fall Chinook salmon upstream of Lower Granite Dam. This is a supplementation project; in that hatchery produced fish are acclimated and released into the natural spawning habitat for the purpose of returning a greater number of spawners to increase natural production. Only Snake River stock is used and production of juveniles occurs at Lyons Ferry Hatchery. This is a long-term project, targeted to work towards achieving

  11. Fall Chinook Aclimation Project; Pittsburg Landing, Captain John Rapids, and Big Canyon, Annual Report 2001.

    Energy Technology Data Exchange (ETDEWEB)

    McLeod, Bruce

    2004-01-01

    Fisheries co-managers of U.S. v Oregon supported and directed the construction and operation of acclimation and release facilities for Snake River fall Chinook from Lyons Ferry Hatchery at three sites above Lower Granite Dam. In 1996, Congress instructed the U.S. Army Corps of Engineers (USCOE) to construct, under the Lower Snake River Compensation Plan (LSRCP), final rearing and acclimation facilities for fall Chinook in the Snake River basin to complement their activities and efforts in compensating for fish lost due to construction of the lower Snake River dams. The Nez Perce Tribe (NPT) played a key role in securing funding and selecting acclimation sites, then assumed responsibility for operation and maintenance of the facilities. In 1997, Bonneville Power Administrative (BPA) was directed to fund operations and maintenance (O&M) for the facilities. Two acclimation facilities, Captain John Rapids and Pittsburg Landing, are located on the Snake River between Asotin, WA and Hells Canyon Dam and one facility, Big Canyon, is located on the Clearwater River at Peck. The Capt. John Rapids facility is a single pond while the Pittsburg Landing and Big Canyon sites consist of portable fish rearing tanks assembled and disassembled each year. Acclimation of 450,000 yearling smolts (150,000 each facility) begins in March and ends 6 weeks later. When available, an additional 2,400,000 fall Chinook sub-yearlings may be acclimated for 6 weeks, following the smolt release. The project goal is to increase the naturally spawning population of Snake River fall Chinook salmon upstream of Lower Granite Dam. This is a supplementation project; in that hatchery produced fish are acclimated and released into the natural spawning habitat for the purpose of returning a greater number of spawners to increase natural production. Only Snake River stock is used and production of juveniles occurs at Lyons Ferry Hatchery. This is a long-term project, and will ultimately work towards achieving

  12. 2008 Weather and Aeolian Sand-Transport Data from the Colorado River Corridor, Grand Canyon, Arizona

    Science.gov (United States)

    Draut, Amy E.; Sondossi, Hoda A.; Hazel, Joseph E., Jr.; Andrews, Timothy; Fairley, Helen C.; Brown, Christopher R.; Vanaman, Karen M.

    2009-01-01

    This report presents measurements of weather parameters and aeolian (windblown) sand transport made in 2008 near selected archaeological sites in the Colorado River corridor through Grand Canyon, Ariz. The quantitative methods and data discussed here form a basis for monitoring ecosystem processes that affect archeological-site stability. Combined with forthcoming work to evaluate landscape evolution at nearby archaeological sites, these data can be used to document the relationship between physical processes, including weather and aeolian sand transport, and their effects on the physical integrity of archaeological sites. Data collected in 2008 reveal event- and seasonal-scale variations in rainfall, wind, temperature, humidity, and barometric pressure. Broad seasonal changes in aeolian sediment flux are also apparent at most study sites. The continuation of monitoring that began in 2007, and installation of equipment at several new sites in early 2008, allowed evaluation of the effects of the March 2008 high-flow experiment (HFE) on aeolian sand transport. At two of the nine sites studied, spring and summer winds reworked 2008 HFE sandbars to form new aeolian dunes, at which sand moved inland toward larger, well-established dune fields. At the other seven study sites, neither dune formation nor enhanced sand transport after the HFE were observed. At several of those sites, dominant wind directions in spring 2008 were not oriented such that much HFE sand would have moved inland; at other sites, lack of increased inland sand flux is attributable to lack of sandbar enlargement near the study sites or to inhibition of sand movement by vegetation or local topography.

  13. Holocene canyon activity under a combination of tidal and tectonic forcing

    Science.gov (United States)

    Mountjoy, Joshu; Micallef, Aaron; Stevens, Craig; Stirling, Mark

    2013-04-01

    The majority of submarine canyon systems that are active during sea level highstands are coupled to terrestrial or littoral sediment transport systems (e.g. high sediment-yield rivers, wave-base sediment disturbance). However, non-coupled canyon systems can also exhibit sedimentary activity. Characterising the nature, origin, and spatial and temporal influence of the processes responsible for this sedimentary activity is important to understand the extent of sediment and carbon transfer to the deep sea, the impact of sedimentary flows on biological colonisation and diversity, and the control of recent seafloor processes on canyon morphology. The Cook Strait canyon system, between the North and South islands of New Zealand, is a large (1800 km2), multi-branching, shelf-indenting canyon on an active subduction margin. The canyon comes within 1 km of the coast, but does not intercept fluvial or littoral sediment systems and is therefore defined as a non-terrestrially-coupled system. Sediment transport on the continental shelf, associated with a strong tidal stream, and seafloor disturbance related to numerous high-activity faults is known from previous studies. Little is known, however, about the rates of sedimentary activity in the canyon and the processes driving it. The canyon system therefore provides an excellent study area for understanding sediment transport in a non-coupled submarine canyon system. Analysis of EM300 multibeam bathymetry, gravity cores, 3.5 kHz seismic reflection profiles, camera and video transects and current meter data reveals a system where oceanographic (tidal) and tectonic (earthquake) processes are moving sediment from the continental shelf, through the upper canyon, and finally to the deep ocean. Sediment accumulation rates may reach several mm/yr in the upper canyons, with data suggesting minimum rates of 0.5 mm/yr. We demonstrate that tidal currents are sufficient to mobilise fine to medium sand around and within the upper canyon

  14. Headless submarine canyons and fluid flow on the toe of the Cascadia accretionary complex

    Science.gov (United States)

    Orange, D.L.; McAdoo, B.G.; Moore, J.C.; Tobin, H.; Screaton, E.; Chezar, H.; Lee, H.; Reid, M.; Vail, R.

    1997-01-01

    Headless submarine canyons with steep headwalls and shallowly sloping floors occur on both the second and third landward vergent anticlines on the toe of the Cascadia accretionary complex off central Oregon (45 ??N, 125?? 30??W). In September 1993, we carried out a series of nine deep tow camera sled runs and nine ALVIN dives to examine the relationship between fluid venting, structure and canyon formation. We studied four canyons on the second and third landward vergent anticlines, as well as the apparently unfailed intercanyon regions along strike. All evidence of fluid expulsion is associated with the canyons; we found no evidence of fluid flow between canyons. Even though all fluid seeps are related to canyons, we did not find seeps in all canyons, and the location of the seeps within the canyons differed. On the landward facing limb of the second landward vergent anticline a robust cold seep community occurs at the canyon's inflection point. This seep is characterized by chemosynthetic vent clams, tube worms and extensive authigenic carbonate. Fluids for this seep may utilize high-permeability flow paths either parallel to bedding within the second thrust ridge or along the underlying thrust fault before leaking into the overriding section. Two seaward facing canyons on the third anticlinal ridge have vent clam communities near the canyon mouths at approximately the intersection between the anticlinal ridge and the adjacent forearc basin. No seeps were found along strike at the intersection of the slope basin and anticlinal ridge. We infer that the lack of seepage along strike and the presence of seeps in canyons may be related to fluid flow below the forearc basin/slope unconformity (overpressured by the impinging thrust fault to the west?) directed toward canyons at the surface.

  15. Element concentrations in surface soils of the Coconino Plateau, Grand Canyon region, Coconino County, Arizona

    Science.gov (United States)

    Van Gosen, Bradley S.

    2016-09-15

    This report provides the geochemical analyses of a large set of background soils collected from the surface of the Coconino Plateau in northern Arizona. More than 700 soil samples were collected at 46 widespread areas, sampled from sites that appear unaffected by mineralization and (or) anthropogenic contamination. The soils were analyzed for 47 elements, thereby providing data on metal concentrations in soils representative of the plateau. These background concentrations can be used, for instance, for comparison to metal concentrations found in soils potentially affected by natural and anthropogenic influences on the Coconino Plateau in the Grand Canyon region of Arizona.The soil sampling survey revealed low concentrations for the metals most commonly of environmental concern, such as arsenic, cobalt, chromium, copper, mercury, manganese, molybdenum, lead, uranium, vanadium, and zinc. For example, the median concentrations of the metals in soils of the Coconino Plateau were found to be comparable to the mean values previously reported for soils of the western United States.

  16. 2010 weather and aeolian sand-transport data from the Colorado River corridor, Grand Canyon, Arizona

    Science.gov (United States)

    Dealy, Timothy P.; East, Amy E.; Fairley, Helen C.

    2014-01-01

    Measurements of weather parameters and aeolian sand transport were made in 2010 near selected archeological sites in the Colorado River corridor through Grand Canyon, Arizona. Data collected in 2010 indicate event- and seasonal-scale variations in rainfall, wind, temperature, humidity, and barometric pressure. Differences in weather patterns between 2009 and 2010 included a slightly later spring windy season, greater spring precipitation and annual rainfall totals, and a later onset and length of the reduced diurnal barometric-pressure fluctuations commonly associated with summer monsoon conditions. The increase in spring precipitation was consistent with the 2010 spring El Niño conditions compared to the 2009 spring La Niña conditions, whereas the subsequent transition to an El Niño-Southern Oscillation neutral phase appeared to delay the reduction in diurnal barometric fluctuations.

  17. Do urban canyons influence street level grass pollen concentrations?

    DEFF Research Database (Denmark)

    Peel, Robert George; Kennedy, Roy; Smith, Matt;

    2014-01-01

    to be statistically significant only in London. The ratio of street/roof level concentrations was compared with temperature, relative humidity, wind speed and direction, and solar radiation. Results indicated that the concentration ratio responds to wind direction with respect to relative canyon orientation and local......In epidemiological studies, outdoor exposure to pollen is typically estimated using rooftop monitoring station data, whilst exposure overwhelmingly occurs at street level. In this study the relationship between street level and roof level grass pollen concentrations was investigated for city centre...... street canyon environments in Aarhus, Denmark, and London, UK, during the grass pollen seasons of 2010 and 2011 respectively. For the period mid-day to late evening, street level concentrations in both cities tended to be lower than roof-level concentrations, though this difference was found...

  18. A review of proposed Glen Canyon Dam interim operating criteria

    Energy Technology Data Exchange (ETDEWEB)

    LaGory, K.; Hlohowskyj, I.; Tomasko, D.; Hayse, J.; Durham, L.

    1992-04-01

    Three sets of interim operating criteria for Glen Canyon Dam on the Colorado River have been proposed for the period of November 1991, to the completion of the record of decision for the Glen Canyon Dam environmental impact statement (about 1993). These criteria set specific limits on dam releases, including maximum and minimum flows, up-ramp and down-ramp rates, and maximum daily fluctuation. Under the proposed interim criteria, all of these parameters would be reduced relative to historical operating criteria to protect downstream natural resources, including sediment deposits, threatened and endangered fishes, trout, the aquatic food base, and riparian plant communities. The scientific bases of the three sets of proposed operating criteria are evaluated in the present report:(1) criteria proposed by the Research/Scientific Group, associated with the Glen Canyon Environmental Studies (GCES); (2) criteria proposed state and federal officials charged with managing downstream resources; and (3) test criteria imposed from July 1991, to November 1991. Data from Phase 1 of the GCES and other sources established that the targeted natural resources are affected by dam operations, but the specific interim criteria chosen were not supported by any existing studies. It is unlikely that irreversible changes to any of the resources would occur over the interim period if historical operating criteria remained in place. It is likely that adoption of any of the sets of proposed interim operating criteria would reduce the levels of sediment transport and erosion below Glen Canyon Dam; however, these interim criteria could result in some adverse effects, including the accumulation of debris at tributary mouths, a shift of new high-water-zone vegetation into more flood-prone areas, and further declines in vegetation in the old high water zone.

  19. A HYBRID APPROACH TO GPS IMPROVEMENT IN URBAN CANYONS

    OpenAIRE

    Ashwani Kumar Aggarwal *

    2015-01-01

    GPS has become important tool in everyday life for safe and convenient transportation of automobiles. Pedestrians use hand held smart devices to know their own position in a town, modern vehicles in intelligent transport systems use relatively sophisticated GPS receivers for estimating current position of vehicle for safe driving. However, in urban areas with canyon of buildings where the GPS satellites are occluded by tall buildings, trees and reflections of GPS signals from near...

  20. Numerical and Experimental Studies on Flow and Pollutant Dispersion in Urban Street Canyons

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In this study numerical simulations and water tank experiments were used to investigate the flow and pollutant dispersion in an urban street canyon. Two types of canyon geometry were tested. The studies indicate that in a step-up notch canyon (higher buildings on the downstream side of the canyon), the height and shape of the upstream lower buildings plays an important role in flow pattern and pollutant dispersion,while in a step-down notch canyon (lower buildings on the downstream side), the downstream lower buildings have little influence. The studies also show that the substitution of tall towers for parallelepiped buildings on one side of the canyon may enhance the street ventilation and decrease the pollutant concentration emitted by motor vehicles.

  1. Aquatic macroinvertebrates and water quality in Sandia Canyon

    International Nuclear Information System (INIS)

    In 1990, field studies of water quality and stream macroinvertebrate communities were initiated in Sandia Canyon at Los Alamos National Laboratory. The studies were designed to establish baseline data and to determine the effects of routine discharges of industrial and sanitary waste. Water quality measurements were taken and aquatic macroinvertebrates sampled at three permanent stations within the canyon. Two of the three sample stations are located where the stream regularly receives industrial and sanitary waste effluents. These stations exhibited a low diversity of macroinvertebrates and slightly degraded water quality. The last sample station, located approximately 0.4 km (0.25 mi) downstream from the nearest wastewater outfall, appears to be in a zone of recovery where water quality parameters more closely resemble those found in natural streams in the Los Alamos area. A large increase in macroinvertebrate diversity was also observed at the third station. These results indicate that effluents discharged into Sandia Canyon have a marked effect on water quality and aquatic macroinvertebrate communities

  2. Do urban canyons influence street level grass pollen concentrations?

    Science.gov (United States)

    Peel, Robert George; Kennedy, Roy; Smith, Matt; Hertel, Ole

    2014-08-01

    In epidemiological studies, outdoor exposure to pollen is typically estimated using rooftop monitoring station data, whilst exposure overwhelmingly occurs at street level. In this study the relationship between street level and roof level grass pollen concentrations was investigated for city centre street canyon environments in Aarhus, Denmark, and London, UK, during the grass pollen seasons of 2010 and 2011 respectively. For the period mid-day to late evening, street level concentrations in both cities tended to be lower than roof-level concentrations, though this difference was found to be statistically significant only in London. The ratio of street/roof level concentrations was compared with temperature, relative humidity, wind speed and direction, and solar radiation. Results indicated that the concentration ratio responds to wind direction with respect to relative canyon orientation and local source distribution. In the London study, an increase in relative humidity was linked to a significant decrease in street/roof level concentration ratio, and a possible causative mechanism involving moisture mediated pollen grain buoyancy is proposed. Relationships with the other weather variables were not found to be significant in either location. These results suggest a tendency for monitoring station data to overestimate exposure in the canyon environment. PMID:24037300

  3. THE INFLUENCE OF BUOYANCY ON FLOW AND POLLUTANT DISPERSION IN STREET CANYONS

    OpenAIRE

    Buccolieri, Riccardo; Pulvirenti, Beatrice; Di Sabatino, Silvana; Britter, Rex

    2008-01-01

    Abstract: In this paper, the effect of buoyancy on flow and pollutant dispersion within street canyons is studied by means of computational fluid dynamics simulations. We consider a neutral boundary layer approaching a 3D street canyon assuming a wind direction perpendicular to the street canyon. The Boussinesq hypothesis for incompressible fluids is chosen for modelling buoyancy. We distinguish three cases: leeward, ground and windward wall heating. Thermal effects on both the flow ...

  4. Trees in urban street canyons and their impact on the dispersion of automobile exhausts

    OpenAIRE

    Gromke, Christof; Ruck, Bodo

    2007-01-01

    The aim of the present study is to clarify the influence of trees on the dispersion of automobile exhausts in urban street canyons. For this purpose, measurements have been performed with a small scale wind tunnel model of an idealized, isolated street canyon with model trees placed along the canyon center axis. Sulfur hexafluoride (SF6) was released from a line source embedded in the street surface, simulating vehicle exhaust emissions. The influence of various tree planting arrangements on ...

  5. Safety-evaluation report related to the operation of Diablo Canyon Nuclear Power Plant, Units 1 and 2 (Docket Nos. 50-275 and 50-323). Supplement No. 16

    International Nuclear Information System (INIS)

    This supplement addresses certain allegations received by the staff concerning safety deficiencies at the Diablo Canyon project, specifically those relative to design aspects of the component cooling water system (CCWS), including its seismic classification, single failure considerations, and its heat removal capabilities. It is based on the staff's re-review of the Diablo Canyon Final Safety Analysis Report (FSAR); on a site walkdown conducted on January 12, 1983; on information obtained during meetings with the applicant dated March 15, 18, and 25, April 4, 7, and 15, and May 3 and 18, 1983

  6. Effects of Backpackers and Stock Use on Wilderness Water Quality in Sequoia & Kings Canyon National Parks

    Science.gov (United States)

    Forrester, H.; Roop, H. A.; Clow, D. W.

    2011-12-01

    Backpackers and pack animals, primarily horses and mules, may impair water quality in high-use zones of federally designated wilderness areas within Sequoia and Kings Canyon National Parks (SEKI). Impacts include erosion from trails, campsites and grazing sites, which increases suspended sediment concentrations and turbidity in downstream water bodies; and fecal matter that may be washed into surface waters during rainstorms or snowmelt periods. The fecal matter also may contain pathogenic bacteria such as Escherichia coli (E. coli) that can pose a health threat to humans. This study aims to establish a working methodology to document and assess effects from backpackers and stock use on physical, chemical and biological water quality parameters. In July 2010, monitoring stations were established within the high-use Crabtree Ranger Station zone. Sites were selected to represent high backpacker use, high pack-animal use, and background conditions. Monitoring stations are instrumented to continuously record water level, temperature, and turbidity and to automatically collect storm samples. Water samples are analyzed for dissolved and particulate nutrients, suspended sediment, and E. coli concentrations. Preliminary data show E. coli counts averaged 4.5 Colony Forming Units/100ml (CFUs) at the high backpacker use, 29.0 CFUs at the high-pack animal use, and 3.4 CFUs at the background sites. Results from the nutrients and suspended sediment analyses are pending. Data collection continued throughout the 2011 field season, with the objective of better quantifying differences in water quality among the study sites.

  7. Compilation of PRF Canyon Floor Pan Sample Analysis Results

    Energy Technology Data Exchange (ETDEWEB)

    Pool, Karl N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Minette, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wahl, Jon H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Greenwood, Lawrence R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Coffey, Deborah S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McNamara, Bruce K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bryan, Samuel A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Scheele, Randall D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Delegard, Calvin H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sinkov, Sergey I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Soderquist, Chuck Z. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fiskum, Sandra K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Brown, Garrett N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Clark, Richard A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-06-30

    On September 28, 2015, debris collected from the PRF (236-Z) canyon floor, Pan J, was observed to exhibit chemical reaction. The material had been transferred from the floor pan to a collection tray inside the canyon the previous Friday. Work in the canyon was stopped to allow Industrial Hygiene to perform monitoring of the material reaction. Canyon floor debris that had been sealed out was sequestered at the facility, a recovery plan was developed, and drum inspections were initiated to verify no additional reactions had occurred. On October 13, in-process drums containing other Pan J material were inspected and showed some indication of chemical reaction, limited to discoloration and degradation of inner plastic bags. All Pan J material was sealed back into the canyon and returned to collection trays. Based on the high airborne levels in the canyon during physical debris removal, ETGS (Encapsulation Technology Glycerin Solution) was used as a fogging/lock-down agent. On October 15, subject matter experts confirmed a reaction had occurred between nitrates (both Plutonium Nitrate and Aluminum Nitrate Nonahydrate (ANN) are present) in the Pan J material and the ETGS fixative used to lower airborne radioactivity levels during debris removal. Management stopped the use of fogging/lock-down agents containing glycerin on bulk materials, declared a Management Concern, and initiated the Potential Inadequacy in the Safety Analysis determination process. Additional drum inspections and laboratory analysis of both reacted and unreacted material are planned. This report compiles the results of many different sample analyses conducted by the Pacific Northwest National Laboratory on samples collected from the Plutonium Reclamation Facility (PRF) floor pans by the CH2MHill’s Plateau Remediation Company (CHPRC). Revision 1 added Appendix G that reports the results of the Gas Generation Rate and methodology. The scope of analyses requested by CHPRC includes the determination of

  8. F-Canyon Sludge Physical Properties

    International Nuclear Information System (INIS)

    The Site Deactivation and Decommissioning (SDD) Organization is evaluating options to disposition the 800 underground tanks (including removal of the sludge heels from these tanks). To support this effort, DandD requested assistance from Savannah River National Laboratory (SRNL) personnel to determine the pertinent physical properties to effectively mobilize the sludge from these tanks (Tanks 804, 808, and 809). SDD provided SRNL with samples of the sludge from Tanks 804, 808, and 809. The authors measured the following physical properties for each tank: particle settling rate, shear strength (i.e., settled solids yield stress), slurry rheology (i.e., yield stress and consistency), total solids concentration in the sludge, soluble solids concentration of the sludge, sludge density, and particle size distribution

  9. Ecology and Taxonomy of Water Canyon, Canadian County, Oklahoma, Master's Thesis, University of Oklahoma 1961 [Revised 2013

    Directory of Open Access Journals (Sweden)

    Constance E. Taylor

    2014-03-01

    Full Text Available Numerous canyons have been cut into the Rush Springs Sandstone of Permian age in West Central Oklahoma and subsequently refilled. Some of these canyons have been partly exposed by erosion of the sediment fill. Fossils collected indicate the canyon fill is sub-Pleistocene to geologically recent. The microclimate of these canyons is more mesic compared to the dryer prairie uplands. Sugar maple (Acer saccharum persists there, far west of its other locations in very eastern Oklahoma. Beginning in 1932 several of these sediment-filled canyons began a process of rapid erosion, exposing the rock walls of the canyons. This study is a comparison of Water Canyon and two of its branches: Water Branch Canyon, a stable canyon wooded with mature vegetation including sugar maple and Activity Branch Canyon, a newly excavated canyon branch that began eroding after excessive rainfall in 1932. This study was completed in 1960. Six transects are used to show the distribution of the 233 plant species found in the Water Canyon complex. Herbaceous species generally were unique to each canyon type.

  10. 2008 High-Flow Experiment at Glen Canyon Dam-Morphologic Response of Eddy-Deposited Sandbars and Associated Aquatic Backwater Habitats along the Colorado River in Grand Canyon National Park

    Science.gov (United States)

    Grams, Paul E.; Schmidt, John C.; Andersen, Matthew E.

    2010-01-01

    The March 2008 high-flow experiment (HFE) at Glen Canyon Dam resulted in sandbar deposition and sandbar reshaping such that the area and volume of associated backwater aquatic habitat in Grand Canyon National Park was greater following the HFE. Analysis of backwater habitat area and volume for 116 locations at 86 study sites, comparing one month before and one month after the HFE, shows that total habitat area increased by 30 percent to as much as a factor of 3 and that volume increased by 80 percent to as much as a factor of 15. These changes resulted from an increase in the area and elevation of sandbars, which isolate backwaters from the main channel, and the scour of eddy return-current channels along the bank where the habitat occurs. Because of this greater relief on the sandbars, backwaters were present across a broader range of flows following the HFE than before the experiment. Reworking of sandbars during diurnal fluctuating flow operations in the first 6 months following the HFE caused sandbar erosion and a reduction of backwater size and abundance to conditions that were 5 to 14 percent greater than existed before the HFE. In the months following the HFE, erosion of sandbars and deposition in eddy return-current channels caused reductions of backwater area and volume. However, sandbar relief was still greater in October 2008 such that backwaters were present across a broader range of discharges than in February 2008. Topographic analyses of the sandbar and backwater morphologic data collected in this study demonstrate that steady flows are associated with a greater amount of continuously available backwater habitat than fluctuating flows, which result in a greater amount of intermittently available habitat. With the exception of the period immediately following the HFE, backwater habitat in 2008 was greater for steady flows associated with dam operations of relatively lower monthly volume (about 227 m3/s) than steady flows associated with dam operations

  11. Restoring Anadromous Fish Habitat in Big Canyon Creek Watershed, 2004-2005 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, Lynn (Nez Perce Soil and Conservation District, Lewiston, ID)

    2006-07-01

    The ''Restoring Anadromous Fish Habitat in the Big Canyon Creek Watershed'' is a multi-phase project to enhance steelhead trout in the Big Canyon Creek watershed by improving salmonid spawning and rearing habitat. Habitat is limited by extreme high runoff events, low summer flows, high water temperatures, poor instream cover, spawning gravel siltation, and sediment, nutrient and bacteria loading. Funded by the Bonneville Power Administration (BPA) as part of the Northwest Power Planning Council's Fish and Wildlife Program, the project assists in mitigating damage to steelhead runs caused by the Columbia River hydroelectric dams. The project is sponsored by the Nez Perce Soil and Water Conservation District. Target fish species include steelhead trout (Oncorhynchus mykiss). Steelhead trout within the Snake River Basin were listed in 1997 as threatened under the Endangered Species Act. Accomplishments for the contract period September 1, 2004 through October 31, 2005 include; 2.7 riparian miles treated, 3.0 wetland acres treated, 5,263.3 upland acres treated, 106.5 riparian acres treated, 76,285 general public reached, 3,000 students reached, 40 teachers reached, 18 maintenance plans completed, temperature data collected at 6 sites, 8 landowner applications received and processed, 14 land inventories completed, 58 habitat improvement project designs completed, 5 newsletters published, 6 habitat plans completed, 34 projects installed, 2 educational workshops, 6 displays, 1 television segment, 2 public service announcements, a noxious weed GIS coverage, and completion of NEPA, ESA, and cultural resources requirements.

  12. Export of terrigenous organic carbon along submarine canyons driven by dense shelf water cascading

    Science.gov (United States)

    Tesi, T.; Puig, P.; Goni, M.; Canals, M.; Langone, L.; Palanques, A.; Miserocchi, S.; Heussner, S.; Trincardi, F.; Calafat, A.; Turchetto, M.; Fabres, J.; Durrieu de Madron, X.; Boldrin, A.

    2008-12-01

    At current highstand in sea level, shelves are considered major sites of terrigenous organic carbon (OCterr) accumulation with relatively little connectivity to the ocean interior. In recent years, the process of dense water cascading from the continental shelf, which occurs in numerous places around the world, has been suggested as carrier for OCterr to the deep ocean. The land-locked Mediterranean Sea is characterized by intense and recurrent cascades of dense shelf water. In winter, cold and dry winds cause the formation of dense water over the shelf that may overflow it and travel down to the outer margin and basin. Moored instruments were deployed in the canyons of the Gulf of Lion (France-Spain) and the Adriatic Sea (Italy) to intercept particulate material escaping the shelf and to investigate hydrodynamic and physical properties of the water column. Surface sediments along the shelves were also sampled to evaluate their contribution to the particle fluxes. The relative fractions of autochthonous and advected OC in sediment trap samples were investigated using biogeochemical proxies including alkaline CuO oxidation products (lignin phenols, dicarboxylic acids, and fatty acids), radiocarbon measurements (Ä14C), and elemental and carbon stable isotope (ä13C) compositions. Lignin-derived CuO products were a powerful biogeochemical tool that allowed us to identify the provenance of the material from the continental margin and to assess the amount of OCterr transferred across the slope in both Mediterranean regions. The results indicate that the composition of OC escaping the shelf through submarine canyons depends on the geomorphological setting. At the present sea level stage, cascading on a broad shelf limits the transport of OCterr, promoting instead the down-slope export of material accumulated in the mid- and outer-shelf. In contrast, cascade events on narrow shelves lead to the efficient export of OCterr from shallower regions of the margin along with

  13. Restoring Anadromous Fish Habitat in Big Canyon Creek Watershed; Anadromous Fish Habitat Restoration in the Nichols Canyon Subwatershed, 2000 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Koziol, Deb (Nez Perce Soil and Water Conservation District, Lewiston, ID)

    2001-02-01

    Nez Perce Soil & Water Conservation District (NPSWCD) undertook the Nichols Canyon Subwatershed Steelhead Trout Habitat Improvement Project in the spring of 1999 with funding from a grant through the Bonneville Power Administration. The Project's purpose is to install and implement agricultural best management practices (MBPS) and riparian restorations with the goal of improving steelhead trout spawning and rearing habitat in the subwatershed. Improvements to fish habitat in the Big Canyon Creek tributaries enhances natural production of the species in Big Canyon Creek and ultimately the Clearwater River. This report is a summation of the progress made by the NPSWCD in the Project's second year.

  14. Impact of bottom trawling on deep-sea sediment properties along the flanks of a submarine canyon.

    Directory of Open Access Journals (Sweden)

    Jacobo Martín

    Full Text Available The offshore displacement of commercial bottom trawling has raised concerns about the impact of this destructive fishing practice on the deep seafloor, which is in general characterized by lower resilience than shallow water regions. This study focuses on the flanks of La Fonera (or Palamós submarine canyon in the Northwestern Mediterranean, where an intensive bottom trawl fishery has been active during several decades in the 400-800 m depth range. To explore the degree of alteration of surface sediments (0-50 cm depth caused by this industrial activity, fishing grounds and control (untrawled sites were sampled along the canyon flanks with an interface multicorer. Sediment cores were analyzed to obtain vertical profiles of sediment grain-size, dry bulk density, organic carbon content and concentration of the radionuclide 210Pb. At control sites, surface sediments presented sedimentological characteristics typical of slope depositional systems, including a topmost unit of unconsolidated and bioturbated material overlying sediments progressively compacted with depth, with consistently high 210Pb inventories and exponential decaying profiles of 210Pb concentrations. Sediment accumulation rates at these untrawled sites ranged from 0.3 to 1.0 cm y-1. Sediment properties at most trawled sites departed from control sites and the sampled cores were characterized by denser sediments with lower 210Pb surface concentrations and inventories that indicate widespread erosion of recent sediments caused by trawling gears. Other alterations of the physical sediment properties, including thorough mixing or grain-size sorting, as well as organic carbon impoverishment, were also visible at trawled sites. This work contributes to the growing realization of the capacity of bottom trawling to alter the physical properties of surface sediments and affect the seafloor integrity over large spatial scales of the deep-sea.

  15. The influence of the San Gregorio fault on the morphology of Monterey Canyon

    Science.gov (United States)

    McHugh, C.M.G.; Ryan, William B. F.; Eittreim, S.; Donald, Reed

    1998-01-01

    A side-scan sonar survey was conducted of Monterey Canyon and the San Gregorio fault zone, off shore of Monterey Bay. The acoustic character and morphology of the sonar images, enhanced by SeaBeam bathymetry, show the path of the San Gregorio fault zone across the shelf, upper slope, and Monterey Canyon. High backscatter linear features a few kilometers long and 100 to 200 m wide delineate the sea-floor expression of the fault zone on the shelf. Previous studies have shown that brachiopod pavements and carbonate crusts are the source of the lineations backscatter. In Monterey Canyon, the fault zone occurs where the path of the canyon makes a sharp bend from WNW to SSW (1800 m). Here, the fault is marked by NW-SE-trending, high reflectivity lineations that cross the canyon floor between 1850 m and 1900 m. The lineations can be traced to ridges on the northwestern canyon wall where they have ~ 15 m of relief. Above the low-relief ridges, bowl-shaped features have been excavated on the canyon wall contributing to the widening of the canyon. We suggest that shear along the San Gregorio fault has led to the formation of the low-relief ridges near the canyon wall and that carbonate crusts, as along the shelf, may be the source of the high backscatter features on the canyon floor. The path of the fault zone across the upper slope is marked by elongated tributary canyons with high backscatter floors and 'U'-shaped cross-sectional profiles. Linear features and stepped scarps suggestive of recent crustal movement and mass-wasting, occur on the walls and floors of these canyons. Three magnitude-4 earthquakes have occurred within the last 30 years in the vicinity of the canyons that may have contributed to the observed features. As shown by others, motion along the fault zone has juxtaposed diverse lithologies that outcrop on the canyon walls. Gully morphology and the canyon's drainage patterns have been influenced by the substrate into which the gullies have formed.

  16. Unusually high food availability in Kaikoura Canyon linked to distinct deep-sea nematode community

    Science.gov (United States)

    Leduc, D.; Rowden, A. A.; Nodder, S. D.; Berkenbusch, K.; Probert, P. K.; Hadfield, M. G.

    2014-06-01

    Kaikoura Canyon, on the eastern New Zealand continental margin, is the most productive, non-chemosynthetic deep-sea habitat described to date, with megafaunal biomass 100-fold higher than those of other deep-sea habitats. The present study, which focused on free-living nematodes, provides the first comparison of faunal community structure and diversity between Kaikoura Canyon and nearby open slope habitats. Results show substantially higher food availability in the canyon relative to open slope sediments, which probably reflects greater levels of primary productivity above the canyon, coupled with downwelling and/or topographically-induced channelling, which serves to concentrate surface-derived organic matter along the canyon axis. This high food availability appears to be responsible for the elevated nematode biomass in Kaikoura Canyon, with values exceeding all published nematode biomass data from canyons elsewhere. There was also markedly lower local species diversity of nematodes inside the canyon relative to the open slope habitat, as well as a distinct community structure. The canyon community was dominated by species, such as Sabateria pulchra, which were absent from the open slope and are typically associated with highly eutrophic and/or disturbed environments. The presence of these taxa, as well as the low observed diversity, is likely to reflect the high food availability, and potentially the high levels of physically and biologically induced disturbance within the canyon. Kaikoura Canyon is a relatively small habitat characterised by different environmental conditions that makes a disproportionate contribution to deep-sea diversity in the region, despite its low species richness.

  17. Water chemistry of surface waters affected by the Fourmile Canyon wildfire, Colorado, 2010-2011

    Science.gov (United States)

    McCleskey, R. Blaine; Writer, Jeffrey H.; Murphy, Sheila F.

    2012-01-01

    In September 2010, the Fourmile Canyon fire burned about 23 percent of the Fourmile Creek watershed in Boulder County, Colo. Water-quality sampling of Fourmile Creek began within a month after the wildfire to assess its effects on surface-water chemistry. Water samples were collected from five sites along Fourmile Creek (above, within, and below the burned area) monthly during base flow, twice weekly during snowmelt runoff, and at higher frequencies during storm events. Stream discharge was also monitored. Water-quality samples were collected less frequently from an additional 6 sites on Fourmile Creek, from 11 tributaries or other inputs, and from 3 sites along Boulder Creek. The pH, electrical conductivity, temperature, specific ultraviolet absorbance, total suspended solids, and concentrations (dissolved and total) of major cations (calcium, magnesium, sodium, and potassium), anions (chloride, sulfate, alkalinity, fluoride, and bromide), nutrients (nitrate, ammonium, and phosphorus), trace metals (aluminum, arsenic, boron, barium, beryllium, cadmium, cobalt, chromium, copper, iron, mercury, lithium, manganese, molybdenum, nickel, lead, rubidium, antimony, selenium, strontium, vanadium, and zinc), and dissolved organic carbon are here reported for 436 samples collected during 2010 and 2011.

  18. Exploring the processes governing roadside pollutant concentrations in urban street canyon.

    Science.gov (United States)

    Galatioto, Fabio; Bell, Margaret C

    2013-07-01

    This paper describes an in-depth analysis to investigate the huge variation in the measured roadside air-pollutant concentrations of carbon monoxide and nitrogen dioxide in terms of the traffic flow levels, the orientation of the street to the prevailing wind, the wind speed, temperature and barometric pressure. The work has attempted to develop generic parameters that can be applied to other urban areas. However, in the absence of a measure of congestion at the site in Palermo (Italy), the methodological approach proposed used the simultaneous noise measurements, in units of decibels (B), to help parameterise a generic congestion indicator in terms of the traffic flow. The potential transferability of the approach was demonstrated for a site in Marylebone Road, London (UK), given the similarity of the two study sites, canyon shape, traffic characteristics and road orientation. The results showed that, within the range of data available, noise levels could be used as a proxy for flow change on the shoulders of the peak hour and hence congestion and a generic relationship with factors statistically significant at 99% confidence allows roadside concentrations due to traffic to be estimated with a regression coefficient of R(2) = 0.73 (R = 0.85). The research demonstrates that whilst there are indeed underlying relationships that can explain the roadside concentrations based on traffic and meteorological conditions, evidence is presented that confirms the complexity of the physical and chemical processes that govern roadside concentrations.

  19. Electrical Resistivity Investigation of Gas Hydrate Distribution in Mississippi Canyon Block 118, Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Dunbar, John

    2012-12-31

    Electrical methods offer a geophysical approach for determining the sub-bottom distribution of hydrate in deep marine environments. Methane hydrate is essentially non-conductive. Hence, sediments containing hydrate are more resistive than sediments without hydrates. To date, the controlled source electromagnetic (CSEM) method has been used in marine hydrates studies. This project evaluated an alternative electrical method, direct current resistivity (DCR), for detecting marine hydrates. DCR involves the injection of direct current between two source electrodes and the simultaneous measurement of the electric potential (voltage) between multiple receiver electrodes. The DCR method provides subsurface information comparable to that produced by the CSEM method, but with less sophisticated instrumentation. Because the receivers are simple electrodes, large numbers can be deployed to achieve higher spatial resolution. In this project a prototype seafloor DCR system was developed and used to conduct a reconnaissance survey at a site of known hydrate occurrence in Mississippi Canyon Block 118. The resulting images of sub-bottom resistivities indicate that high-concentration hydrates at the site occur only in the upper 50 m, where deep-seated faults intersect the seafloor. Overall, there was evidence for much less hydrate at the site than previously thought based on available seismic and CSEM data alone.

  20. Design of a sediment-monitoring gaging network on ephemeral tributaries of the Colorado River in Glen, Marble, and Grand Canyons, Arizona

    Science.gov (United States)

    Griffiths, Ronald E.; Topping, David J.; Anderson, Robert S.; Hancock, Gregory S.; Melis, Theodore S.

    2014-01-01

    stations beginning in 2000 on the larger of the previously ungaged tributaries of the Colorado River downstream from Glen Canyon Dam. The sediment-monitoring gaging stations consist of a downward-looking stage sensor and passive suspended-sediment samplers. Two stations are equipped with automatic pump samplers to collect suspended-sediment samples during flood events. Directly measuring discharge and collecting suspended-sediment samples in these remote ephemeral streams during significant sediment-transporting events is nearly impossible; most significant run-off events are short-duration events (lasting minutes to hours) associated with summer thunderstorms. As the remote locations and short duration of these floods make it prohibitively expensive, if not impossible, to directly measure the discharge of water or collect traditional depth-integrated suspended-sediment samples, a method of calculating sediment loads was developed that includes documentation of stream stages by field instrumentation, modeling of discharges associated with these stages, and automatic suspended-sediment measurements. The approach developed is as follows (1) survey and model flood high-water marks using a two-dimensional hydrodynamic model, (2) create a stage-discharge relation for each site by combining the modeled flood flows with the measured stage record, (3) calculate the discharge record for each site using the stage-discharge relation and the measured stage record, and (4) calculate the instantaneous and cumulative sediment loads using the discharge record and suspended-sediment concentrations measured from samples collected with passive US U-59 samplers and ISCOTM pump samplers. This paper presents the design of the gaging network and briefly describes the methods used to calculate discharge and sediment loads. The design and methods herein can easily be used at other remote locations where discharge and sediment loads are required.

  1. Aerodynamic effects of trees on pollutant concentration in street canyons.

    Science.gov (United States)

    Buccolieri, Riccardo; Gromke, Christof; Di Sabatino, Silvana; Ruck, Bodo

    2009-09-15

    This paper deals with aerodynamic effects of avenue-like tree planting on flow and traffic-originated pollutant dispersion in urban street canyons by means of wind tunnel experiments and numerical simulations. Several parameters affecting pedestrian level concentration are investigated, namely plant morphology, positioning and arrangement. We extend our previous work in this novel aspect of research to new configurations which comprise tree planting of different crown porosity and stand density, planted in two rows within a canyon of street width to building height ratio W/H=2 with perpendicular approaching wind. Sulfur hexafluoride was used as tracer gas to model the traffic emissions. Complementary to wind tunnel experiments, 3D numerical simulations were performed with the Computational Fluid Dynamics (CFD) code FLUENT using a Reynolds Stress turbulence closure for flow and the advection-diffusion method for concentration calculations. In the presence of trees, both measurements and simulations showed considerable larger pollutant concentrations near the leeward wall and slightly lower concentrations near the windward wall in comparison with the tree-less case. Tree stand density and crown porosity were found to be of minor importance in affecting pollutant concentration. On the other hand, the analysis indicated that W/H is a more crucial parameter. The larger the value of W/H the smaller is the effect of trees on pedestrian level concentration regardless of tree morphology and arrangement. A preliminary analysis of approaching flow velocities showed that at low wind speed the effect of trees on concentrations is worst than at higher speed. The investigations carried out in this work allowed us to set up an appropriate CFD modelling methodology for the study of the aerodynamic effects of tree planting in street canyons. The results obtained can be used by city planners for the design of tree planting in the urban environment with regard to air quality issues

  2. Effect of Fetch on a Mechanism for Pollutant Removal from a Two-Dimensional Street Canyon

    Science.gov (United States)

    Michioka, Takenobu; Takimoto, Hiroshi; Ono, Hiroki; Sato, Ayumu

    2016-07-01

    Large-eddy simulation is conducted to investigate the effect of fetch on the pollutant-removal mechanism from a two-dimensional street canyon with a building-height to street-width (aspect) ratio of 1. The line sources were placed within the first, second, third, fifth, seventh and tenth canyons, and the six tracer gases are simultaneously released by a ground-level continuous pollutant line source placed parallel to the spanwise axis at the canyons. The mean concentration and the deviation of the concentration fluctuation within the canyon roughly reach a near-constant value downwind of the seventh canyon, which is similar to the behaviour of the turbulent intensities. In the first canyon, pollutant removal is affected by both advective flow and turbulent flow; however, the turbulent motions mainly affect pollutant removal from the top of the canyon as the fetch increases. In the first and third canyons, the low-momentum fluid does not always affect pollutant removal, but does so gradually as the fetch increases.

  3. 78 FR 42799 - Glen Canyon Dam Adaptive Management Work Group Meetings

    Science.gov (United States)

    2013-07-17

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group Meetings AGENCY: Bureau of... AMWG, a technical work group (TWG), a Grand Canyon Monitoring and Research Center, and independent.... Dated: July 11, 2013. Glen Knowles, Chief, Adaptive Management Work Group, Upper Colorado...

  4. 75 FR 44809 - Glen Canyon Dam Adaptive Management Work Group (AMWG)

    Science.gov (United States)

    2010-07-29

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group (AMWG) AGENCY: Bureau of Reclamation.... L. 102-575) of 1992. The AMP includes a Federal advisory committee, the Adaptive Management Work Group (AMWG), a technical work group (TWG), a Grand Canyon Monitoring and Research Center,...

  5. 76 FR 584 - Glen Canyon Dam Adaptive Management Program Work Group (AMWG)

    Science.gov (United States)

    2011-01-05

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Program Work Group (AMWG) AGENCY: Bureau of... Management Work Group (AMWG), a technical work group (TWG), a Grand Canyon Monitoring and Research Center... addition, there will be updates from the Charter Ad Hoc Group and a follow up report on the work done...

  6. 75 FR 439 - Glen Canyon Dam Adaptive Management Work Group (AMWG)

    Science.gov (United States)

    2010-01-05

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group (AMWG) AGENCY: Bureau of Reclamation.... L. 102-575) of 1992. The AMP includes a Federal advisory committee, the Adaptive Management Work Group (AMWG), a Technical Work Group (TWG), a Grand Canyon Monitoring and Research Center,...

  7. 33 CFR 165.1155 - Security Zone; Diablo Canyon Nuclear Power Plant, Avila Beach, California.

    Science.gov (United States)

    2010-07-01

    ... Nuclear Power Plant, Avila Beach, California. 165.1155 Section 165.1155 Navigation and Navigable Waters... Coast Guard District § 165.1155 Security Zone; Diablo Canyon Nuclear Power Plant, Avila Beach... surface to bottom, within a 2,000 yard radius of Diablo Canyon Nuclear Power Plant centered at position...

  8. 75 FR 10838 - Pacific Gas and Electric Company; Diablo Canyon Power Plant; Exemption

    Science.gov (United States)

    2010-03-09

    ... COMMISSION Pacific Gas and Electric Company; Diablo Canyon Power Plant; Exemption 1.0 Background Pacific Gas... DPR-82, which authorize operation of the Diablo Canyon Power Plant, Units Nos. 1 and 2 (DCPP). The... materials,'' Section 73.55, ``Requirements for physical protection of licensed activities in nuclear...

  9. 75 FR 8152 - Pacific Gas and Electric Company; Diablo Canyon Power Plant Environmental Assessment and Finding...

    Science.gov (United States)

    2010-02-23

    ... COMMISSION Pacific Gas and Electric Company; Diablo Canyon Power Plant Environmental Assessment and Finding... Pacific Gas and Electric Company (PG&E, the licensee), for operation of the Diablo Canyon Power Plant... Part 73 as discussed in a Federal Register notice dated March 27, 2009 (74 FR 13926). There will be...

  10. 77 FR 7211 - Pacific Gas and Electric Company, Diablo Canyon Independent Spent Fuel Storage Installation...

    Science.gov (United States)

    2012-02-10

    ... COMMISSION Pacific Gas and Electric Company, Diablo Canyon Independent Spent Fuel Storage Installation... Manager, Division of Spent Fuel Storage and Transportation, Office of Nuclear Material Safety and... Pacific Gas and Electric Company (PG&E) for the Diablo Canyon (DC) Independent Spent Fuel...

  11. 75 FR 12315 - Pacific Gas and Electric Company; Diablo Canyon Independent Spent Fuel Storage Installation...

    Science.gov (United States)

    2010-03-15

    ... COMMISSION Pacific Gas and Electric Company; Diablo Canyon Independent Spent Fuel Storage Installation..., Division of Spent Fuel Storage and Transportation, Office of Nuclear Material Safety and Safeguards, Mail... Gas and Electric Company (PG&E) for the Diablo Canyon Independent Spent Fuel Storage...

  12. 75 FR 26098 - Safety Zone; Under Water Clean Up of Copper Canyon, Lake Havasu, AZ

    Science.gov (United States)

    2010-05-11

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Under Water Clean Up of Copper Canyon, Lake... vessels. Basis and Purpose The Lake Havasu Divers Association is sponsoring the Under Water Copper Canyon Clean up, which will involve 40 divers cleaning the river bottom in Lake Havasu. The Coast Guard...

  13. Captured in Stone: Women in the Rock Art of Canyon de Chelly.

    Science.gov (United States)

    Travis, Tara

    1997-01-01

    Describes the pictographs (painted images on stone) and petroglyphs (pecked images on stone) found in the Canyon de Chelly National Monument in Arizona. Canyon de Chelly includes one of the largest concentrations of American Indian rock art in the southwest. Discusses the depiction of women in these images. (MJP)

  14. Las presas de Glen Canyon y Flaming Gorge

    Directory of Open Access Journals (Sweden)

    Goodman, D. L.

    1962-04-01

    Full Text Available El Bureau of Reclamation, con sede en Denver, Colorado (EE. UU., está actualmente construyendo dos presas, de hormigón y gran altura. Este Departamento desempeña una función similar a la que vienen desarrollando nuestras Confederaciones hidrográficas nacionales. Las dos presas son: la de Glen Canyon, de 216 m de altura, y la de Flaming Gorge, de 153, que son las más importantes en cuanto a almacenamiento y reserva se refiere.

  15. An exhumed Late Paleozoic canyon in the rocky mountains

    Science.gov (United States)

    Soreghan, G.S.; Sweet, D.E.; Marra, K.R.; Eble, C.F.; Soreghan, M.J.; Elmore, R.D.; Kaplan, S.A.; Blum, M.D.

    2007-01-01

    Landscapes are thought to be youthful, particularly those of active orogenic belts. Unaweep Canyon in the Colorado Rocky Mountains, a large gorge drained by two opposite-flowing creeks, is an exception. Its origin has long been enigmatic, but new data indicate that it is an exhumed late Paleozoic landform. Its survival within a region of profound late Paleozoic orogenesis demands a reassessment of tectonic models for the Ancestral Rocky Mountains, and its form and genesis have significant implications for understanding late Paleozoic equatorial climate. This discovery highlights the utility of paleogeomorphology as a tectonic and climatic indicator. ?? 2007 by The University of Chicago. All rights reserved.

  16. Bathymetry and Canyons of the western Solomon Sea

    Science.gov (United States)

    Davies, H. L.; Keene, J. B.; Hashimoto, K.; Joshima, M.; Stuart, J. E.; Tiffin, D. L.

    1986-12-01

    The floor of the western Solomon Sea (for new bathymetric map see inside back cover of this issue) is dominated by the arched and ridged basement of the Solomon Sea Basin, the partly-sediment-filled New Britain Trench, and a more completely filled trench, the Trobriand Trough. There is a deep basin where the trenches join (149° Embayment), and a silled basin west of the New Britain Trench (Finsch Deep). Submarine canyons descend from the west and south to the 149° Embayment. Abyssal fans and plains are structurally defined and locally disturbed by young faults. Probable submerged pinnacle reefs stand in water depths as great as 1,200 m.

  17. Exploration of the canyon-incised continental margin of the northeastern United States reveals dynamic habitats and diverse communities

    Science.gov (United States)

    Quattrini, Andrea; Nizinski, Martha S.; Chaytor, Jason; Demopoulos, Amanda; Roark, E. Brendan; France, Scott; Moore, Jon A.; Heyl, Taylor P.; Auster, Peter J.; Ruppel, Carolyn; Elliott, Kelley P.; Kennedy, Brian R.C.; Lobecker, Elizabeth A.; Skarke, Adam; Shank, Timothy M.

    2015-01-01

    The continental margin off the northeastern United States (NEUS) contains numerous, topographically complex features that increase habitat heterogeneity across the region. However, the majority of these rugged features have never been surveyed, particularly using direct observations. During summer 2013, 31 Remotely-Operated Vehicle (ROV) dives were conducted from 494 to 3271 m depth across a variety of seafloor features to document communities and to infer geological processes that produced such features. The ROV surveyed six broad-scale habitat features, consisting of shelf-breaching canyons, slope-sourced canyons, inter-canyon areas, open-slope/landslide-scar areas, hydrocarbon seeps, and Mytilus Seamount. Four previously unknown chemosynthetic communities dominated by Bathymodiolus mussels were documented. Seafloor methane hydrate was observed at two seep sites. Multivariate analyses indicated that depth and broad-scale habitat significantly influenced megafaunal coral (58 taxa), demersal fish (69 taxa), and decapod crustacean (34 taxa) assemblages. Species richness of fishes and crustaceans significantly declined with depth, while there was no relationship between coral richness and depth. Turnover in assemblage structure occurred on the middle to lower slope at the approximate boundaries of water masses found previously in the region. Coral species richness was also an important variable explaining variation in fish and crustacean assemblages. Coral diversity may serve as an indicator of habitat suitability and variation in available niche diversity for these taxonomic groups. Our surveys added 24 putative coral species and three fishes to the known regional fauna, including the black coral Telopathes magna, the octocoral Metallogorgia melanotrichosand the fishes Gaidropsarus argentatus, Guttigadus latifrons, and Lepidion guentheri. Marine litter was observed on 81% of the dives, with at least 12 coral colonies entangled in debris. While initial

  18. Exploration of the Canyon-Incised Continental Margin of the Northeastern United States Reveals Dynamic Habitats and Diverse Communities.

    Science.gov (United States)

    Quattrini, Andrea M; Nizinski, Martha S; Chaytor, Jason D; Demopoulos, Amanda W J; Roark, E Brendan; France, Scott C; Moore, Jon A; Heyl, Taylor; Auster, Peter J; Kinlan, Brian; Ruppel, Carolyn; Elliott, Kelley P; Kennedy, Brian R C; Lobecker, Elizabeth; Skarke, Adam; Shank, Timothy M

    2015-01-01

    The continental margin off the northeastern United States (NEUS) contains numerous, topographically complex features that increase habitat heterogeneity across the region. However, the majority of these rugged features have never been surveyed, particularly using direct observations. During summer 2013, 31 Remotely-Operated Vehicle (ROV) dives were conducted from 494 to 3271 m depth across a variety of seafloor features to document communities and to infer geological processes that produced such features. The ROV surveyed six broad-scale habitat features, consisting of shelf-breaching canyons, slope-sourced canyons, inter-canyon areas, open-slope/landslide-scar areas, hydrocarbon seeps, and Mytilus Seamount. Four previously unknown chemosynthetic communities dominated by Bathymodiolus mussels were documented. Seafloor methane hydrate was observed at two seep sites. Multivariate analyses indicated that depth and broad-scale habitat significantly influenced megafaunal coral (58 taxa), demersal fish (69 taxa), and decapod crustacean (34 taxa) assemblages. Species richness of fishes and crustaceans significantly declined with depth, while there was no relationship between coral richness and depth. Turnover in assemblage structure occurred on the middle to lower slope at the approximate boundaries of water masses found previously in the region. Coral species richness was also an important variable explaining variation in fish and crustacean assemblages. Coral diversity may serve as an indicator of habitat suitability and variation in available niche diversity for these taxonomic groups. Our surveys added 24 putative coral species and three fishes to the known regional fauna, including the black coral Telopathes magna, the octocoral Metallogorgia melanotrichos and the fishes Gaidropsarus argentatus, Guttigadus latifrons, and Lepidion guentheri. Marine litter was observed on 81% of the dives, with at least 12 coral colonies entangled in debris. While initial exploration

  19. Variability in turbidity current frequency within a central Portuguese margin canyon

    Science.gov (United States)

    Allin, Joshua R.; Talling, Peter J.; Hunt, James E.; Clare, Michael E.; Pope, Ed

    2015-04-01

    Submarine canyons constitute one of the most important pathways for sediment transport into ocean basins. For this reason, understanding canyon architecture and sedimentary processes has significance for oil and gas reservoir characterisation, carbon budgets and geohazard assessment. Canyon sedimentation in the form of turbidity-currents is known to operate on a variety of scales and result from a number of different processes, including landslides, river-derived hyperpycnal flows and tidal or storm resuspension. Despite the expanding knowledge of turbidity current triggers, the spatial variability in turbidity current frequency within most canyon systems is not well defined. Here, new chronologies from cores in the lower reaches of Nazaré Canyon illustrate changes in turbidity current frequency and their relationship to sea level. These flows were relatively frequent during the last glacial maximum and the last deglaciation, with an average recurrence interval of ~70 years. Mid to early Holocene slowdown in activity (avg. recurrence of 1625 years) appears to occur later than other systems along the Iberian margin. Cores from the Iberian Abyssal Plain also provide the first recurrence interval estimates for large run-out turbidity currents from the central Portuguese margin. These large turbidity currents have an average recurrence interval of 2750 years, broadly comparable to modern turbidity flow events in the lower Nazaré Canyon. This indicates that Nazaré Canyon acted as a depocentre, capturing large volumes of sediment during glacial periods prior to large scale canyon flushing events. However, this sediment capture has largely been restricted to the middle and upper canyon since stabilisation of Holocene sea level. Recurrence intervals suggest that large turbidity flows which flush the canyon operate on a timescale independent of the sea level forcing evident in the lower canyon. While instability-triggered landsliding and tidal/storm resuspension are

  20. 76 FR 47237 - Notice of Public Meeting for the Glen Canyon Dam Adaptive Management Work Group Federal Advisory...

    Science.gov (United States)

    2011-08-04

    ... Bureau of Reclamation Notice of Public Meeting for the Glen Canyon Dam Adaptive Management Work Group... Canyon Dam Adaptive Management Work Group (AMWG) makes recommendations to the Secretary of the Interior..., the AMWG, a technical work group (TWG), a Grand Canyon Monitoring and Research Center, and...

  1. Large eddy simulation of flow in a street canyon with tree planting under various atmospheric instability conditions

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this work, a large eddy simulation (LES) model, which includes momentum and heat source (or sink) inside the tree planting layer, is proposed for the simulation of flow in a street canyon with tree planting. Vegetation canopy layer simulation shows that this model can be used to simulate the velocity distribution and temperature variation inside the canopy layer. Effects of atmospheric instability on flow and pollutant distribution in a street canyon with tree planting of an aspect ratio of 0.5 are studied. Results show that compared with the canyon with no tree planting (or the exposed street canyon), the canyon with tree planting shows a reduced wind circulation and pollutant exchange rate (PER) at the top layer of the street canyon, which induces the increase in the pollutant concentrations near road surface, leeward wall and windward wall. When street canyon atmosphere is under a strongly unstable condition, wind velocity decreases while pollutant concentration is increased in the areas near the street canyon top, road surface, leeward and windward walls, compared with the wind velocity in the street canyon with the neutral stratification. When street canyon atmosphere is under a weakly unstable condition, wind velocity weakens near the street canyon top and windward wall, but strengthens near the road surface and leeward wall, and pollutant concentration is decreased near the leeward and windward walls and is increased between the two rows of trees. When the street canyon atmosphere is under an unstable condition, PER is lower than that under the neutral stratification.

  2. Preliminary Thermal Modeling of HI-STORM 100 Storage Modules at Diablo Canyon Power Plant ISFSI

    Energy Technology Data Exchange (ETDEWEB)

    Cuta, Judith M.; Adkins, Harold E.

    2014-04-17

    Thermal analysis is being undertaken at Pacific Northwest National Laboratory (PNNL) in support of inspections of selected storage modules at various locations around the United States, as part of the Used Fuel Disposition Campaign of the U.S. Department of Energy, Office of Nuclear Energy (DOE-NE) Fuel Cycle Research and Development. This report documents pre-inspection predictions of temperatures for two modules at the Diablo Canyon Power Plant ISFSI identified as candidates for inspection. These are HI-STORM 100 modules of a site-specific design for storing PWR 17x17 fuel in MPC-32 canisters. The temperature predictions reported in this document were obtained with detailed COBRA-SFS models of these storage systems, with the following boundary conditions and assumptions. • storage module overpack configuration based on FSAR documentation of HI-STORM100S-218, Version B; due to unavailability of site-specific design data for Diablo Canyon ISFSI modules • Individual assembly and total decay heat loadings for each canister, based on at-loading values provided by PG&E, “aged” to time of inspection using ORIGEN modeling o Special Note: there is an inherent conservatism of unquantified magnitude – informally estimated as up to approximately 20% -- in the utility-supplied values for at-loading assembly decay heat values • Axial decay heat distributions based on a bounding generic profile for PWR fuel. • Axial location of beginning of fuel assumed same as WE 17x17 OFA fuel, due to unavailability of specific data for WE17x17 STD and WE 17x17 Vantage 5 fuel designs • Ambient conditions of still air at 50°F (10°C) assumed for base-case evaluations o Wind conditions at the Diablo Canyon site are unquantified, due to unavailability of site meteorological data o additional still-air evaluations performed at 70°F (21°C), 60°F (16°C), and 40°F (4°C), to cover a range of possible conditions at the time of the inspection. (Calculations were also performed at

  3. Comparing the Grand Canyon of the East to the Western one

    Science.gov (United States)

    Gorom, J.; Martinez-Hackert, B.

    2007-12-01

    The Grand Canyon of the West (GCW) is an internationally well-known geological world wonder of the South Western United States' Colorado Plateau. The Grand Canyon of the East is a similarly beautiful, less well-known, smaller canyon in the Devonian/Silurian sedimentary rocks of the western part of New York State in the Eastern United States. For the purpose of creating a comparative database to be used in the field, classroom and public education settings, features of New York's canyon, better known as Letchworth State Park (LSP) to Arizona's canyon, were collected, obtained, and recorded. We compared various numbers on rock formations, ages of the units, stream volume, and depth and age of canyon formation, erosion processes and other interesting geological features between the two canyons. The sedimentary rocks of both canyons tell the story of the conditions under which the rocks were laid onto the Earth's surface at the time. This study includes an evaluation of how the two canyons have formed including features we see in the strata. Literature research revealed that LSP is on the order of 10 times smaller than the Grand Canyon in various aspects. Genesee river is up to only 4 m deep while the Colorado River reaches depths of up to 30 m. The Genesee extends 25.3 km within its canyon, paling at the majestic 445.79km of the Colorado within its canyon. The depths of the two canyons also show how small LSP is in comparison to the GCW Letchworth canyon's depth is 0.17 km while GCW is 1.61 km. The width of LSP's canyon is 0.1 km while the Grand Canyons' is 28.97 km at their widest locations. Fieldwork in both canyons allowed for some comparison of the natural waterfall features within the canyons. With help from a laser range finder measurements were taken from the most prominent waterfalls of LSP and the Havasu creek. Rock formations were compared. While the periods of Precambrian to the middle Permian time are found in the GCW, the Silurian/Devonian formations are

  4. Remedial action plan and site design for stabilization of the inactive uranium processing site at Naturita, Colorado. Appendix A of Attachment 3: Calculations, Final

    Energy Technology Data Exchange (ETDEWEB)

    1994-03-01

    This report contains calculations for: hydraulic gradients for Alluvial Aquifer and Salt Wash Aquifer; slug test analysis to determine hydraulic conductivity for Alluvial Aquifer and Salt Wash Aquifer; average linear groundwater velocity for Alluvial Aquifer and Salt Wash Aquifer; statistical analysis of the extent of existing groundwater contamination; hydraulic gradients for Dakota/Burro Canyon Formation and Salt Wash Aquifer; slug test analysis to determine hydraulic conductivity for Dakota/Burro Canyon Formation and Perched Salt Wash Aquifer; determination of hydraulic conductivity of the Dakota/Burro Canyon Formation from Packer Tests; average linear groundwater velocity for Dakota/Burro Canyon and Salt Wash Aquifer; chemical and mineralogical characterization of core samples from the Dry Flats Disposal Site; and demonstration of low groundwater yield from Uppermost Aquifer.

  5. Xenophyophores (Rhizaria, Foraminifera) from the Nazaré Canyon (Portuguese margin, NE Atlantic)

    Science.gov (United States)

    Gooday, A. J.; Aranda da Silva, A.; Pawlowski, J.

    2011-12-01

    Xenophyophores are abundant on a terrace of the lower Nazaré Canyon (4300 m water depth) on the Portuguese margin. Here, the most abundant species, Reticulammina cerebreformis sp. nov., occurs in densities of up to 21 individuals/m 2. This large species has a soft, friable hemispherical test up to 10 cm in diameter consisting of curved, sinuous plates (lamellae) that branch and anastomose. The plates are separated by deep furrows and other depressions to form a distinctive 'brain-like' structure. The outer test layer is thin, weakly cemented and is dominated by fine sediment particles; the internal xenophyae include a higher proportion of larger mineral grains. The second new species at the 4300-m site, Nazareammina tenera gen. et sp. nov., is much less common. The test is basically plate-like, but towards the interior it is perforated by oval spaces, which typically merge into complex system of bar-like features, sometimes with irregular excrescences. The granellare system (cell body and its organic envelope) is packed with tiny mineral grains of various sizes and shapes, including titanium-bearing particles. Also common at this deep site are clusters, with a maximum diameter up to 10 cm or occasionally more, of irregular tubes belonging to Aschemonella ramuliformis Brady 1884, a species previously known mainly from isolated tubes. Rather than being single individuals, these clusters comprise a large number of separate branched tubes. Finally, Syringammina fragillissima Brady 1883, a well-known species that is widely distributed on the NW European margin, occurred on steep sediment-covered slopes at a shallower (1555 m water depth) site in the upper canyon. Almost complete SSU rDNA gene sequences obtained from A. ramuliformis and R. cerebreformis confirm that these xenophyophores are foraminifera. Together with two previously sequenced xenophophores ( Shinkaia lindsayi Lecroq, Gooday, Tsuchiya, Pawlowski 2009 and Syringammina corbicula Richardson 2001), and the

  6. Environmental assessment, Deaf Smith County site, Texas

    Energy Technology Data Exchange (ETDEWEB)

    1986-05-01

    The Nuclear Waste Policy Act of 1982 (42 USC sections 10101-10226) requires the environmental assessment of a proposed site to include a statement of the basis for nominating a site as suitable for characterization. Volume 2 provides a detailed statement evaluating the site suitability of the Deaf Smith County Site under DOE siting guidelines, as well as a comparison of the Deaf Smith County Site to the other sites under consideration. The evaluation of the Deaf Smith County Site is based on the impacts associated with the reference repository design, but the evaluation will not change if based on the Mission Plan repository concept. The second part of this document compares the Deaf Smith County Site to Davis Canyon, Hanford, Richton Dome and Yucca Mountain. This comparison is required under DOE guidelines and is not intended to directly support subsequent recommendation of three sites for characterization as candidate sites. 259 refs., 29 figs., 66 refs. (MHB)

  7. Environmental assessment, Deaf Smith County site, Texas

    International Nuclear Information System (INIS)

    The Nuclear Waste Policy Act of 1982 (42 USC sections 10101-10226) requires the environmental assessment of a proposed site to include a statement of the basis for nominating a site as suitable for characterization. Volume 2 provides a detailed statement evaluating the site suitability of the Deaf Smith County Site under DOE siting guidelines, as well as a comparison of the Deaf Smith County Site to the other sites under consideration. The evaluation of the Deaf Smith County Site is based on the impacts associated with the reference repository design, but the evaluation will not change if based on the Mission Plan repository concept. The second part of this document compares the Deaf Smith County Site to Davis Canyon, Hanford, Richton Dome and Yucca Mountain. This comparison is required under DOE guidelines and is not intended to directly support subsequent recommendation of three sites for characterization as candidate sites. 259 refs., 29 figs., 66 refs

  8. Are deep-sea organisms dwelling within a submarine canyon more at risk from anthropogenic contamination than those from the adjacent open slope? A case study of Blanes canyon (NW Mediterranean)

    Science.gov (United States)

    Koenig, Samuel; Fernández, Pilar; Company, Joan B.; Huertas, David; Solé, Montserrat

    2013-11-01

    Due to their geomorphological structure and proximity to the coastline, submarine canyons may act as natural conduit routes for anthropogenic contaminants that are transported from surface waters to the deep-sea. Organisms dwelling in these canyon environments might thus be at risk of experiencing adverse health effects due to higher pollution exposure. To address this question, chemical and biochemical analyses were conducted on two of the most abundant deep-sea fish species in the study area, namely Alepocephalus rostratus and Lepidion lepidion, and the most abundant deep-sea commercial decapod crustacean Aristeus antennatus sampled inside Blanes canyon (BC) and on the adjacent open slope (OS). Persistent organic pollutants (POPs) levels, including polychlorinated biphenyl (PCB), dichlorodiphenyltrichloroethane (DDT) and derivatives, hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB) were determined in muscle tissue of selected samples from 900 m and 1500 m depth. Potential effects resulting from contaminant exposure were determined using hepatic biomarkers such as ethoxyresorufin-O-deethylase (EROD), pentoxyresorufin-O-deethylase (PROD), catalase (CAT), carboxylesterase (CbE), glutathione-S-transferase (GST), total glutathione peroxidase (GPX), glutathione reductase (GR) and superoxide-dismutase (SOD) enzyme activities and lipid peroxidation levels (LP). L. lepidion and A. antennatus tissues exhibited higher POP levels inside BC compared to the OS at 900 m depth. These findings were consistent with biomarker data (i.e. enzymatic response to presence of contaminant agents). Elevated xenobiotic-metabolizing (EROD and PROD) and antioxidant enzymes (CAT and GPX) indicated higher contaminant exposure in both species caught within BC. No difference in POP accumulation between sites was observed in L. lepidion at 1500 m depth, nor in biomarker data, suggesting that the pollution gradient was less pronounced at greater depths. This trend was further corroborated

  9. Bathymetry and acoustic backscatter of the mid and outer continental shelf, head of De Soto Canyon, northeastern Gulf of Mexico

    Science.gov (United States)

    Gardner, James V.; Hughes-Clarke, John E.; Meyer, Larry A.

    2002-01-01

    The mid to outer continental shelf off Mississippi-Alabama and off northwest Florida were the focus of US Geological Survey (USGS) multibeam echosounder (MBES) mapping cruises in 2000 and 2001, respectively. These areas were mapped to investigate the extent of "deep-water reefs" first suggested by Ludwick and Walton (1957). The reefs off Mississippi and Alabama were initially described in water depths of 60 to 120 m (Ludwick and Walton, 1957) but the 2000 mapping found reef and hardgrounds to be much more extensive than previously thought (Gardner et al., 2001). The persistent trend of reef-like features along the outer shelf of Mississippi-Alabama suggested the trend might continue along the northwest Florida mid and outer shelf so a MBES-mapping effort was mounted in 2001 to test this suggestion. It is critical to determine the accurate location, geomorphology, and types of the ridges and reefs that occur in this region to understand the Quaternary history of the area and to assess their importance as benthic habitats for fisheries. The 2001 survey found a series of shelf-depth platforms with ridges (possibly reefs) constructed on their surfaces (Gardner et al., 2002). The area known as the "head of De Soto Canyon" is the large unmapped region between the 2000 and 2001 mapped areas. The head of De Soto Canyon is an outer shelf zone with a relatively steep western wall and a much gentler eastern wall. It was unknown prior to this cruise whether the reefs of the Mississippi-Alabama shelf continue eastward into the head of De Soto Canyon and connect with the ridges and reefs mapped on the northwest Florida outer shelf. The existence of carbonate-cemented latest Quaternary to Holocene sandstones along the western wall of the head of De Soto Canyon (Shipp and Hopkins, 1978; Benson et al., 1997; W.W. Schroeder, personnel comm., 2002) is of interest because of the potential benthic habitats they may represent. Precisely georeferenced high-resolution mapping of

  10. Fall Chinook Acclimation Project; Pittsburg Landing, Captain John Rapids, and Big Canyon, Annual Report 2002.

    Energy Technology Data Exchange (ETDEWEB)

    McLeod, Bruce

    2003-01-01

    Fisheries co-managers of U.S. v Oregon supported and directed the construction and operation of acclimation and release facilities for Snake River fall Chinook from Lyons Ferry Hatchery at three sites above Lower Granite Dam. In 1996, Congress instructed the U.S. Army Corps of Engineers (USCOE) to construct, under the Lower Snake River Compensation Plan (LSRCP), final rearing and acclimation facilities for fall Chinook in the Snake River basin to complement their activities and efforts in compensating for fish lost due to construction of the lower Snake River dams. The Nez Perce Tribe (NPT) played a key role in securing funding and selecting acclimation sites, then assumed responsibility for operation and maintenance of the facilities. In 1997, Bonneville Power Administrative (BPA) was directed to fund operations and maintenance (O&M) for the facilities. Two acclimation facilities, Captain John Rapids and Pittsburg Landing, are located on the Snake River between Asotin, WA and Hells Canyon Dam and one facility, Big Canyon, is located on the Clearwater River at Peck. The Capt. John Rapids facility is a single pond while the Pittsburg Landing and Big Canyon sites consist of portable fish rearing tanks assembled and disassembled each year. Acclimation of 450,000 yearling smolts (150,000 each facility) begins in March and ends 6 weeks later. When available, an additional 2,400,000 fall Chinook sub-yearlings may be acclimated for 6 weeks, following the smolt release. The project goal is to increase the naturally spawning population of Snake River fall Chinook salmon upstream of Lower Granite Dam. This is a supplementation project; in that hatchery produced fish are acclimated and released into the natural spawning habitat for the purpose of returning a greater number of spawners to increase natural production. Only Snake River stock is used and production of juveniles occurs at Lyons Ferry Hatchery. This is a long-term project, targeted to work towards achieving

  11. Megafauna of vulnerable marine ecosystems in French mediterranean submarine canyons: Spatial distribution and anthropogenic impacts

    Science.gov (United States)

    Fabri, M.-C.; Pedel, L.; Beuck, L.; Galgani, F.; Hebbeln, D.; Freiwald, A.

    2014-06-01

    Vulnerable Marine Ecosystems (VME) in the deep Mediterranean Sea have been identified by the General Fisheries Commission for the Mediterranean as consisting of communities of Scleractinia (Lophelia pertusa and Madrepora oculata), Pennatulacea (Funiculina quadrangularis) and Alcyonacea (Isidella elongata). This paper deals with video data recorded in the heads of French Mediterranean canyons. Quantitative observations were extracted from 101 video films recorded during the MEDSEACAN cruise in 2009 (Aamp/Comex). Qualitative information was extracted from four other cruises (two Marum/Comex cruises in 2009 and 2011 and two Ifremer cruises in 1995 and 2010) to support the previous observations in the Cassidaigne and Lacaze-Duthiers canyons. All the species, fishing impacts and litter recognized in the video films recorded from 180 to 700 m depth were mapped using GIS. The abundances and distributions of benthic fishing resources (marketable fishes, Aristeidae, Octopodidae), Vulnerable Marine Species, trawling scars and litter of 17 canyons were calculated and compared, as was the open slope between the Stoechades and Toulon canyons. Funiculina quadrangularis was rarely observed, being confined for the most part to the Marti canyon and, I. elongata was abundant in three canyons (Bourcart, Marti, Petit-Rhône). These two cnidarians were encountered in relatively low abundances, and it may be that they have been swept away by repeated trawling. The Lacaze-Duthiers and Cassidaigne canyons comprised the highest densities and largest colony sizes of scleractinian cold-water corals, whose distribution was mapped in detail. These colonies were often seen to be entangled in fishing lines. The alcyonacean Callogorgia verticillata was observed to be highly abundant in the Bourcart canyon and less abundant in several other canyons. This alcyonacean was also severely affected by bottom fishing gears and is proposed as a Vulnerable Marine Species. Our studies on anthropogenic

  12. Effects of hydropower operations on recreational use and nonuse values at Glen Canyon and Flaming Gorge Dams

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, J.L.

    1995-03-01

    Increases in streamflows are generally positively related to the use values of angling and white-water boating, and constant flows tend to increase the use values more than fluctuating flows. In most instances, however, increases in streamflows beyond some threshold level cause the use values to decrease. Expenditures related to angling and white-water boating account for about $24 million of activity in the local economy around Glen Canyon Dam and $24.8 million in the local economy around flaming Gorge Dam. The range of operational scenarios being considered in the Western Area Power Administration`s Electric Power Marketing Environmental Impact Statement, when use rates are held constant, could change the combined use value of angling and white-water boating below Glen Canyon Dam, increasing it by as much as 50%, depending on prevailing hydrological conditions. Changes in the combined use value below Flaming Gorge Dam could range from a decrease of 9% to an increase of 26%. Nonuse values, such as existence and bequest values, could also make a significant contribution to the total value of each site included in this study; however, methodological and data limitations prevented estimating how each operational scenario could change nonuse values.

  13. Floodplain Assessment for the Proposed Engineered Erosion Controls at TA-72 in Lower Sandia Canyon, Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Hathcock, Charles D. [Los Alamos National Laboratory

    2012-08-27

    Los Alamos National Laboratory (LANL) is preparing to implement engineering controls in Sandia Canyon at Technical Area (TA) 72. Los Alamos National Security (LANS) biologists conducted a floodplain determination and this project is located within a 100-year floodplain. The proposed project is to rehabilitate the degraded channel in lower Sandia Canyon where it crosses through the outdoor firing range at TA-72 to limit the loss of sediment and dissipate floodwater leaving LANL property (Figure 1). The proposed construction of these engineered controls is part of the New Mexico Environment Department's (NMED) approved LANL Individual Storm Water Permit. The purpose of this project is to install storm water controls at Sandia Watershed Site Monitoring Area 6 (S-SMA-6). Storm water controls will be designed and installed to meet the requirements of NPDES Permit No. NM0030759, commonly referred to as the LANL Individual Storm Water Permit (IP). The storm water control measures address storm water mitigation for the area within the boundary of Area of Concern (AOC) 72-001. This action meets the requirements of the IP for S-SMA-6 for storm water controls by a combination of: preventing exposure of upstream storm water and storm water generated within the channel to the AOC and totally retaining storm water falling outside the channel but within the AOC.

  14. Strontium concentrations in chamisa (Chrysothamnus nauseosus) shrub plants growing in a former liquid waste disposal area in Bayo Canyon

    International Nuclear Information System (INIS)

    Chamisa (Chrysothamnus nauseosus) shrub plants growing in a former liquid waste disposal site Solid Waste Management Unit [SWMU] 10-003(c) in Bayo Canyon at Los Alamos National Laboratory (LANL) were collected and analyzed for strontium (90Sr) and total uranium. Surface soil samples were also collected from below (understory) and between (interspace) shrub canopies. Both chamisa plants growing over SWMU 10-003(c) contained significantly higher concentrations of 90Sr than a control plant -- one plant, in particular, contained 90, 500 pCi 90Sr g-1 ash in top-growth material. Similarly, soil surface samples collected underneath and between plants contained 90Sr concentrations above background and LANL screening action levels; this probably occurred as a result of chamisa plant leaf fall contaminating the soil understory area followed by water and/or winds moving 90Sr to the soil interspace area. Although some soil surface migration of 90Sr from SWMU 10-003(c) has occurred, the level of 90Sr in sediments collected downstream of SWMU 10-003(c) at the Bayo Canyon/State Road 5 intersection was still within regional (background) concentrations

  15. Klondike III/Biglow Canyon Wind Integration Project; Final Environmental Impact Statement, September 2006.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration

    2006-09-01

    BPA has been asked by PPM Energy, Inc. to interconnect 300 megawatts (MW) of electricity generated from the proposed Klondike III Wind Project to the Federal Columbia River Transmission System. Orion Energy LLC has also asked BPA to interconnect 400 MW of electricity from its proposed Biglow Canyon Wind Farm, located north and east of the proposed Klondike III Wind Project. (Portland General Electric recently bought the rights to develop the proposed Biglow Canyon Wind Farm from Orion Energy, LLC.) Both wind projects received Site Certificates from the Oregon Energy Facility Siting Council on June 30, 2006. To interconnect these projects, BPA would need to build and operate a 230-kV double-circuit transmission line about 12 miles long, expand one substation and build one new substation. The wind projects would require wind turbines, substation(s), access roads, and other facilities. Two routes for the transmission line are being considered. Both begin at PPM's Klondike Schoolhouse Substation then travel north (Proposed Action) or north and westerly (Middle Alternative) to a new BPA 230-kV substation next to BPA's existing John Day 500-kV Substation. BPA is also considering a No Action Alternative in which BPA would not build the transmission line and would not interconnect the wind projects. The proposed BPA and wind projects would be located on private land, mainly used for agriculture. If BPA decides to interconnect the wind projects, construction of the BPA transmission line and substation(s) could commence as early as the winter of 2006-07. Both wind projects would operate for much of each year for at least 20 years. The proposed projects would generally create no or low impacts. Wildlife resources and local visual resources are the only resources to receive an impact rating other than ''none'' or ''low''. The low to moderate impacts to wildlife are from the expected bird and bat mortality and the cumulative

  16. Scattering and diffraction of plane SH-waves by periodically distributed canyons

    Science.gov (United States)

    Ba, Zhenning; Liang, Jianwen; Zhang, Yanju

    2016-06-01

    A new method is presented to study the scattering and diffraction of plane SH-waves by periodically distributed canyons in a layered half-space. This method uses the indirect boundary element method combined with Green's functions of uniformly distributed loads acting on periodically distributed inclined lines. The periodicity feature of the canyons is exploited to limit the discretization effort to a single canyon, which avoids errors induced by the truncation of the infinite boundary, and the computational complexity and the demand on memory can be significantly reduced. Furthermore, the total wave fields are decomposed into the free field and scattered field in the process of calculation, which means that the method has definite physical meaning. The implementation of the method is described in detail and its accuracy is verified. Parametric studies are performed in the frequency domain by taking periodically distributed canyons of semi-circular and semi-elliptic cross-sections as examples. Numerical results show that the dynamic responses of periodically distributed canyons can be quite different from those for a single canyon and significant dynamic interactions exist between the canyons.

  17. The World's Largest Submarine Canyon—Kroenke Canyon in the Western Equatorial Pacific

    Science.gov (United States)

    Coffin, M. F.; Adams, N.; Whittaker, J. M.; Lucieer, V.; Heckman, M.; Ketter, T.; Neale, J. F.; Reyes, A.; Travers, A.

    2015-12-01

    Kroenke Canyon lies on the Ontong Java Plateau (OJP) in the western Equatorial Pacific, between the Solomon Islands and the Federated States of Micronesia. In late 2014 aboard the Schmidt Ocean Institute's RV Falkor, we mapped, albeit incompletely, the Canyon for the first time, revealing that it is both the longest (>700 km) and the most voluminous (>6800 km3) submarine canyon yet discovered on Earth. Kroenke Canyon appears to originate in the vicinity of Ontong Java (Solomon Islands) and Nukumanu (Papua New Guinea) atolls, and presumably began to develop when the atolls were high-standing volcanic islands surmounting the ~120 Ma igneous basement of the OJP. The Canyon is characterised by numerous tributaries and significant mass wasting. Kroenke Canyon incises the layer-cake stratigraphy of OJP sediment and sedimentary rock, mostly carbonate with some interbedded chert, which has provided numerous slip surfaces for submarine landslides. The carbonate compensation depth (CCD) roughly coincides with the depth of the transition between the OJP and the neighbouring Nauru Basin. As a result, despite the large volume of sediment eroded and transported by canyon-forming processes, only a minor fan is evident in the Nauru Basin because most of the carbonate has dissolved.

  18. Modelled transport of benthic marine microplastic pollution in the Nazaré Canyon

    Science.gov (United States)

    Ballent, A.; Pando, S.; Purser, A.; Juliano, M. F.; Thomsen, L.

    2013-12-01

    With knowledge of typical hydrodynamic behavior of waste plastic material, models predicting the dispersal of benthic plastics from land sources within the ocean are possible. Here we investigated the hydrodynamic behavior (density, settling velocity and resuspension characteristics) of non-buoyant preproduction plastic pellets in the laboratory. From these results we used the MOHID modelling system to predict what would be the likely transport and deposition pathways of such material in the Nazaré Canyon (Portugal) during the spring/summer months of 2009 and the autumn/winter months of 2011. Model outputs indicated that non-buoyant plastic pellets would likely be transported up and down canyon as a function of tidal forces, with only a minor net down canyon movement resulting from tidal action. The model indicated that transport down canyon was likely greater during the autumn/winter, primarily as a result of occasional mass transport events related to storm activity and internal wave action. Transport rates within the canyon were not predicted to be regular throughout the canyon system, with stretches of the upper canyon acting more as locations of pellet deposition than conduits of pellet transport. Topography and the depths of internal wave action are hypothesized to contribute to this lack of homogeneity in predicted transport.

  19. OPTIMIZING LAYOUT OF URBAN STREET CANYON USING NUMERICAL SIMULATION COUPLING WITH MATHEMATICAL OPTIMIZATION

    Institute of Scientific and Technical Information of China (English)

    WANG Jia-song; ZHAO Bao-qing; YE Chun; YANG De-qing; HUANG Zhen

    2006-01-01

    Optimizing the layout of the urban street canyon to achieve the maximum environmental benefits should become a new idea for modern urban street design and planning. This paper aims to find out the optimized street canyon from a viewpoint of environmental protection by using the two-dimensional numerical simulation model with the turbulence model, coupling with the mathematical optimization method. The total pollutant concentration within and at top of the specific street canyons was taken as the objective function, and the height of one side of the canyon as the constrained condition. A nonlinearly improved constrained variable metric solver was used. The effect of the height of the leeward building and windward building on the integrated pollutant dispersion was studied to achieve the most beneficial configuration of the urban geometry. The optimization of layout for an asymmetrical street canyon was obtained. It is further found that the step-down street canyon with a large height difference is generally a good layout favoring to reduce the concentration accumulation in the street canyon.

  20. Gully monitoring at two locations in the Grand Canyon National Park, Arizona, 1996-2010, with emphasis on documenting effects of the March 2008 high-flow experiment

    Science.gov (United States)

    Schott, Nathan D.; Hazel, Joseph E., Jr.; Fairley, Helen C.; Kaplinski, Matt; Parnell, Roderic A.

    2014-01-01

    Many archeological sites in the Grand Canyon are being impacted by gully incision. In March 2008, a high-flow experiment (2008 HFE) was conducted with the intention of redistributing fine sediment (sand, silt, and clay) from the bed of the Colorado River to higher elevations along the channel margin. Deposition of fine sediment in gully mouths has been hypothesized to slow gully erosion rates and lessen impacts to archeological sites. The effects of the 2008 HFE on gullies were evaluated by comparing the topographic changes of three gullies at two study sites before and after the 2008 HFE. Comparison results indicated that sediment was deposited in gully mouths during the 2008 HFE, and that the inundated areas nearest to the river can be extensively altered by mainstream flow during high-flow events. Additionally, the history of gully evolution at the two study sites was examined between 1996 and 2010 and indicated that gullies have been subjected to thalweg incision and gully widening processes over a decadal timescale. Although the small sample size precludes extrapolating the results to other gullies, the findings contribute to the understanding of gully erosion in archeologically significant areas and have implications for future monitoring of gully erosion and evaluating the effectiveness of check dams intended to mitigate that erosion at archaeological sites in the Grand Canyon National Park.

  1. Facies and depositional model of Almada Canyon, Almada Basin, Bahia, Brazil; Facies e modelo deposicional do Canyon de Almada, Bacia de Almada, Bahia

    Energy Technology Data Exchange (ETDEWEB)

    D' Avila, Roberto Salvador Francisco; Souza Cruz, Carlos Emanoel de; Oliveira Filho, Jose Souto; Jesus, Candida Menezes de; Cesero, Pedro de; Dias Filho, Dorval Carvalho; Lima, Claudio Coelho de; Queiroz, Claudia Lima de; Santos, Saulo Ferreira; Ferreira, Eduardo Araripe [PETROBRAS, Santos, SP (Brazil). Unidade de Negocio de Exploracao]. E-mail: rdavila@petrobras.com.br

    2004-11-01

    In the continental portion of the Almada Basin outcrops of canyon filling deposits are represented by turbidite channels and associated facies from Urucutuca Formation. The canyon - semi-exhumated - eroded basement and pre-Cenomanian sedimentary rocks. The field study of the outcrops and cores obtained in adjacent perforations lead to the understanding of the facies and processes that controlled the deposition of these channeled turbidite that can be compared to the reservoirs of many oil fields in Brazil. The Almada canyon is a submarine conduct of tectonic origin that was enlarged by the repeated passing of turbidity currents. During the rift phase and the Albian period, compressive events reactivated old N E and N W faults in the basement as trans current fault systems. The continuation of these stresses, from the Cenomanian to the Maastrichtian, developed normal faults that controlled a submarine canyon that connected the continent, where an estuary was formed between the mountains, to the deep marine region of the basin. The canyon has received sediments brought by catastrophic fluvial floods coming from the surrounding mountains, which formed hyperpicnal flows that have evolved as turbidity currents, thus causing erosion of the substrate and carrying a huge volume of sediments to the basin. A part of that load was deposited in the canyon and formed turbidite channels filled by conglomerates, sandstones and shales. These moderately to highly efficient turbidite are intercalated to pro delta pelites and low density turbid plumes deposits, which have mostly been re mobilized as slump and debris flows (chaotic deposits). Pelites were accumulated mainly in the normal fluvial sedimentation phases, when the sandy sediment was retained next to the canyon head and were reworked by the tides on the upper part of the estuary. (author)

  2. NUMERICAL STUDIES ON AIRFLOW AND POLLUTANT DISPERSION IN URBAN STREET CANYONS FORMED BY SLANTED ROOF BUILDINGS

    Institute of Scientific and Technical Information of China (English)

    HUANG Yuan-dong; JIN Ming-xia; SUN Ya-nan

    2007-01-01

    Based on the CFD technique, fifteen cases were evaluated for the airflows and pollutant dispersions inside urban street canyons formed by slanted roof buildings. The simulated wind fields and concentration contours show that W/H, W/h and h/H (where W is the street width, and H and h are the heights of buildings at the leeward and windward sides of the street, respectively) are the crucial factors in determining the vortex structure and pollutant distribution within a canyon. It is concluded that (1) in a symmetrical canyon, at W/H =0.5 two vortices (an upper clockwise vortex between the slanted roofs and a lower counter-clockwise one) are developed and pollutants accumulate on the windward side of the street, whereas at W/H=2.0 only one clockwise vortex is generated and thus pollution piles up on the leeward side, (2) in a step-up canyon with W/H =0.5 to 2.0 (at h/H =1.5 to 2.0)and a step-down canyon with W/h=1.0 (at h/H =0.5 to 0.667), the pollution level close to the lower building is higher than that close to the taller building since a clockwise vortex is generated in the step-up canyon and a counter-clockwise one in the step-down canyon, (3) in a narrow step-down canyon with W/h=0.5 (at h/H =0.667) very poor ventilation properties is detected, and inside a wider step-down canyon with W/h=2.0 the vortex structure and consequently pollutant distribution varies greatly with h/H.

  3. Exposure pathways and biological receptors: baseline data for the canyon uranium mine, Coconino County, Arizona

    Science.gov (United States)

    Hinck, Jo E.; Linder, Greg L.; Darrah, Abigail J.; Drost, Charles A.; Duniway, Michael C.; Johnson, Matthew J.; Méndez-Harclerode, Francisca M.; Nowak, Erika M.; Valdez, Ernest W.; Van Riper, Charles; Wolff, S.W.

    2014-01-01

    Recent restrictions on uranium mining within the Grand Canyon watershed have drawn attention to scientific data gaps in evaluating the possible effects of ore extraction to human populations as well as wildlife communities in the area. Tissue contaminant concentrations, one of the most basic data requirements to determine exposure, are not available for biota from any historical or active uranium mines in the region. The Canyon Uranium Mine is under development, providing a unique opportunity to characterize concentrations of uranium and other trace elements, as well as radiation levels in biota, found in the vicinity of the mine before ore extraction begins. Our study objectives were to identify contaminants of potential concern and critical contaminant exposure pathways for ecological receptors; conduct biological surveys to understand the local food web and refine the list of target species (ecological receptors) for contaminant analysis; and collect target species for contaminant analysis prior to the initiation of active mining. Contaminants of potential concern were identified as arsenic, cadmium, chromium, copper, lead, mercury, nickel, selenium, thallium, uranium, and zinc for chemical toxicity and uranium and associated radionuclides for radiation. The conceptual exposure model identified ingestion, inhalation, absorption, and dietary transfer (bioaccumulation or bioconcentration) as critical contaminant exposure pathways. The biological survey of plants, invertebrates, amphibians, reptiles, birds, and small mammals is the first to document and provide ecological information on .200 species in and around the mine site; this study also provides critical baseline information about the local food web. Most of the species documented at the mine are common to ponderosa pine Pinus ponderosa and pinyon–juniper Pinus–Juniperus spp. forests in northern Arizona and are not considered to have special conservation status by state or federal agencies; exceptions

  4. Effects of a covering layer in a circular-arc canyon on incident plane SV waves

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    An analytical solution for scattering of incident plane SV waves by a circular-arc canyon with a covering layer was derived by Fourier-Bessel series expansion technique, and the solution was utilized to analyze the effects of the covering layer on incident plane SV waves. It was shown that the covering layer in a canyon, even if it is very thin, amplifies incident plane SV waves tremendously, and the amplification can be two and half times more than that for a simple canyon; the stiffness and thickness of the covering layer also have great effects on incident plane SV waves.

  5. Comparative study of measured and modelled number concentrations of nanoparticles in an urban street canyon

    DEFF Research Database (Denmark)

    Kumar, Prashant; Garmory, Andrew; Ketzel, Matthias;

    2009-01-01

    This study presents a comparison between measured and modelled particle number concentrations (PNCs) in the 10-300 nm size range at different heights in a canyon. The PNCs were modelled using a simple modelling approach (modified Box model, including vertical variation), an Operational Street...... entire height of the canyon, showing a well-mixed region up to first ≈2 m and then decreasing PNCs with increased height. The CFD profiles do correctly reproduce the increase from road level to a height of ≈2 m; however, they do not predict the measured PNC decrease higher in the canyon. The PNC...

  6. Nearshore temperature findings for the Colorado River in Grand Canyon, Arizona: possible implications for native fish

    Science.gov (United States)

    Ross, Robert P.; Vernieu, William S.

    2013-01-01

    Since the completion of Glen Canyon Dam, Arizona, in 1963, downstream water temperatures in the main channel of the Colorado River in Glen, Marble, and Grand Canyons are much colder in summer. This has negatively affected humpback chub (Gila cypha) and other native fish adapted to seasonally warm water, reducing main-channel spawning activity and impeding the growth and development of larval and juvenile fish. Recently published studies by U.S. Geological Survey scientists found that under certain conditions some isolated nearshore environments in Grand Canyon allow water to become separated from the main-channel current and to warm, providing refuge areas for the development of larval and juvenile fish.

  7. 2009 weather and aeolian sand-transport data from the Colorado River corridor, Grand Canyon, Arizona

    Science.gov (United States)

    Draut, Amy E.; Sondossi, Hoda A.; Dealy, Timothy P.; Hazel, Joseph E., Jr.; Fairley, Helen C.; Brown, Christopher R.

    2010-01-01

    This report presents measurements of weather parameters and aeolian sand transport made in 2009 near selected archeological sites in the Colorado River corridor through Grand Canyon, Ariz. The quantitative methods and data discussed here form a basis for monitoring ecosystem processes that affect archeological-site stability. Combined with forthcoming work to evaluate landscape evolution at nearby archeological sites, these data can be used to document the relation between physical processes, including weather and aeolian sand transport, and their effects on the physical integrity of archeological sites. Data collected in 2009 reveal event- and seasonal-scale variations in rainfall, wind, temperature, humidity, and barometric pressure. Broad seasonal changes in aeolian sediment flux are also apparent at most study sites. Differences in weather patterns between 2008 and 2009 included an earlier spring windy season, greater spring precipitation even though 2009 annual rainfall totals were in general substantially lower than in 2008, and earlier onset of the reduced diurnal barometric-pressure fluctuations commonly associated with summer monsoon conditions. Weather patterns in middle to late 2009 were apparently affected by a transition of the ENSO cycle from a neutral phase to the El Ni?o phase. The continuation of monitoring that began in 2007, and installation of additional equipment at several new sites in early 2008, allowed evaluation of the effects of the March 2008 high-flow experiment (HFE) on aeolian sand transport. As reported earlier, at 2 of the 9 sites studied, spring and summer winds in 2008 reworked the HFE sandbars to form new aeolian dunes, where sand moved inland toward larger, well-established dune fields. Observations in 2009 showed that farther inland migration of the dune at one of those two sites is likely inhibited by vegetation. At the other location, the new aeolian dune form was found to have moved 10 m inland toward older, well

  8. National uranium resource evaluation, Marble Canyon Quadrangle, Arizona and Utah

    International Nuclear Information System (INIS)

    The Marble Canyon Quadrangle (20), northeast Arizona, was evaluated to a depth of 1500 m for uranium favorability using National Uranium Resource Evaluation criteria. Known mines and prospects were examined; field reconnaissance was done in selected areas of the quadrangle; and a ground-water geochemical survey was made in the southeast third of the quadrangle. The Shinarump and Petrified Forest Members of the Triassic Chinle Formation, which is exposed in the western and northeastern parts of the quadrangle and is present beneath the surface of much of the quadrangle, were found favorable for channel-sandstone uranium deposits. A portion of the Cretaceous Toreva Formation in the southeast part of the quadrangle was found favorable for peneconcordant-sandstone uranium deposits. The western part of the quadrangle was found favorable for uranium concentrations in breccia pipes

  9. Achieving quality excellence at the Diablo Canyon Nuclear Power Plant

    International Nuclear Information System (INIS)

    Quality assurance methods at the Diablo Canyon plant were transformed from the then typical industry practices that often alienated professional and technical people, as well as craftsmen and their foremen, to a cooperative method that allowed plant personnel to work together as a team. It has created an attitude to do it right the first time. The roles of quality professionals were expanded to include teaching and coaching to facilitate enhanced communication between and within functional organizations. This included regular presentations to managers and line personnel in an informal group participative atmosphere. These presentations have become widely known at the plant as quality awareness tailboard sessions. These presentations are intended to increase personnel sensitivity to the subject of quality and quality management. Economic achievement of excellence in quality is essential to remain competitive in today's marketplace. The proactive team-oriented approach of quality assurance achieves the bottom line of high quality with concurrently enhanced productivity and cost-effectiveness

  10. Web-based Interactive Landform Simulation Model - Grand Canyon

    Science.gov (United States)

    Luo, W.; Pelletier, J. D.; Duffin, K.; Ormand, C. J.; Hung, W.; Iverson, E. A.; Shernoff, D.; Zhai, X.; Chowdary, A.

    2013-12-01

    Earth science educators need interactive tools to engage and enable students to better understand how Earth systems work over geologic time scales. The evolution of landforms is ripe for interactive, inquiry-based learning exercises because landforms exist all around us. The Web-based Interactive Landform Simulation Model - Grand Canyon (WILSIM-GC, http://serc.carleton.edu/landform/) is a continuation and upgrade of the simple cellular automata (CA) rule-based model (WILSIM-CA, http://www.niu.edu/landform/) that can be accessed from anywhere with an Internet connection. Major improvements in WILSIM-GC include adopting a physically based model and the latest Java technology. The physically based model is incorporated to illustrate the fluvial processes involved in land-sculpting pertaining to the development and evolution of one of the most famous landforms on Earth: the Grand Canyon. It is hoped that this focus on a famous and specific landscape will attract greater student interest and provide opportunities for students to learn not only how different processes interact to form the landform we observe today, but also how models and data are used together to enhance our understanding of the processes involved. The latest development in Java technology (such as Java OpenGL for access to ubiquitous fast graphics hardware, Trusted Applet for file input and output, and multithreaded ability to take advantage of modern multi-core CPUs) are incorporated into building WILSIM-GC and active, standards-aligned curricula materials guided by educational psychology theory on science learning will be developed to accompany the model. This project is funded NSF-TUES program.

  11. Brittle deformation and hoodoo development in Bryce Canyon National Park

    Science.gov (United States)

    Haddon, E. K.; Webb, C.; McNitt, J.; Pollock, G. L.; Davis, L.; MacLean, J. S.

    2015-12-01

    Bryce Canyon is a dramatic southeast-facing escarpment located in the transition zone between the Basin and Range Province and the Colorado Plateau. Stream erosion of the Paleocene-to-Eocene Claron Formation generates vast amphitheaters and alcoves replete with elaborate fins, windowed walls, and hoodoos from Fairyland to Bryce Point. Geomorphic models of hoodoo development describe the influence of differential weathering and ice wedging along systematic vertical fractures formed during uplift of the Colorado Plateau. Conjugate shear fractures in the footwall of the south-vergent Rubys Inn thrust fault may provide additional preexisting weaknesses intersecting the predominantly flat-lying strata. During a summer 2015 GeoCorpsTM America internship, we investigated the contribution of joint sets to focused erosion of exposed fins and hoodoo development in Bryce Canyon National Park. Our field mapping documents the nature and spatial distribution of known fractures as well as a previously undocumented third generation characterized by steeply-dipping conjugates and zones of distributed deformation. Evidence for normal reactivation of contractional structures in the Sevier River drainage (MacLean, 2014) suggests that distributed deformation evolved during Basin and Range extension, possibly associated with the nearby Paunsaugunt fault. Cross-cutting relations among fracture sets suggest modest uplift and vertical jointing prior to collapse of the Marysvale volcanic complex (~22-20 Ma) and more recent Basin and Range extension. Spatial trends in fracture density illustrate a systematic increase in vertical, shear fractures, and reactivated zones to the north, proximal to thrust faulting. The increase in fracture density leads to accelerated weathering and erosion, with a corresponding increase in windows, hoodoos, and gentle slopes. While erosional windows commonly develop along vertical fractures intersecting relatively weak lithologies, approximately 60% of the 130

  12. MOBILIZATION, POISONING, AND FILTRATION OF F-CANYON TANK 804 SLUDGE

    Energy Technology Data Exchange (ETDEWEB)

    Poirier, M; Thomas Peters, T; Samuel Fink, S

    2006-05-04

    The Savannah River Site (SRS) Deactivation and Decommissioning (SDD) Organization is evaluating options to disposition the F-Canyon 800 series underground tanks (including removal of the sludge heels from these tanks) and requested assistance from Savannah River National Laboratory (SRNL) personnel to develop methods to effectively mobilize the sludge from these tanks (i.e., Tanks 804, 808, and 809). Because of the high plutonium content in Tank 804 (estimated to be as much as 1500 g), SDD needs to add a neutron poison to the sludge. They considered manganese and boron as potential poisons. Because of the large amount of manganese needed and the very slow filtration rate of the sludge/manganese slurry, SDD requested that SRNL investigate the impact of using boron rather than manganese as the poison. SRNL performed a series of experiments to help determine the disposal pathway of the material currently located in Tank 804. The objectives of this work are: (1) Determine the mobility of Tank 804 sludge when mixed with 10-15 parts sodium hydroxide as a function of pH between 10 and 14. (2) Determine the solubility of boron in sodium hydroxide solution with a free hydroxide concentration between 1 x 10{sup -4} and 2.0 M. (3) Recommend a filter pore size for SDD such that the filtrate contains no visible solids. (4) Determine whether a precipitate forms when the filtrate pH is adjusted to 12, 7, or 2 with nitric acid.

  13. Synthetic Seismograms Derived from Oceanographic Data in the Campeche Canyon, Deepwater Gulf of Mexico

    Science.gov (United States)

    Gonzalez-Orduno, A.; Fucugauchi, J. U.; Monreal, M.; Perez-Cruz, G.; Salas de León, D. A.

    2013-05-01

    The seismic reflection method has been successfully applied worldwide to investigate subsurface conditions to support important business decisions in the oil industry. When applied in the marine environment, useful reflection information is limited to events on and below the sea floor; Information from the water column, if any, is disregarded. Seismic oceanography is emerging as a new technique that utilize the reflection information within the water column to infer thermal-density contrasts associated with oceanographic processes, such as cyclonic-anticyclonic eddies, ascending-descending water flows, and water flows related to rapid topographic changes on the sea floor. A seismic investigation to infer such oceanographic changes in one sector of the Campeche Canyon is in progress as a research matter at the Instituto de Ciencias del Mar y Limnologia from the University of Mexico (UNAM). First steps of the investigation consisted of creating synthetic seismograms based on oceanographic information (temperature and density) derived from direct observation on a series of close spaced depth points along vertical profiles. Details of the selected algorithms used for the transformation of the oceanographic data to acoustic impedances data sets and further construction of synthetic seismograms on each site and their representation as synthetic seismic sections, are presented in this work, as well as the road ahead in the investigation.

  14. Spatial Vegetation Data for Sequoia and Kings Canyon National Parks Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — High resolution vegetation polygons mapped by the National Park Service. The Vegetation Map of Sequoia and Kings Canyon National Parks was produced over an eight...

  15. Collembolan species diversity of calcareous canyons in the Republic of Moldova.

    Science.gov (United States)

    Buşmachiu, Galina; Bedos, Anne; Deharveng, Louis

    2015-01-01

    The study of collembolan communities from the Vîşcăuți canyon in Moldova revealed 63 species belonging to 41 genera and 12 families, including four species new for the fauna of the Republic of Moldova. A checklist of collembolan species identified in the five calcareous canyons sampled so far in Moldova is included, with data on habitats, life form, occurrence and comments of distribution of most remarkable species. Of the 98 recognized species of these calcareous canyons, only 38 were shared by Vîşcăuți and the other canyons. The richness of calcareous habitats together with the high heterogeneity in faunal composition suggests that further significant increase in the species richness of the region may be expected.

  16. BackscatterA [USGS SWATH]--Monterey Canyon and Vicinity, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the acoustic-backscatter map of Monterey Canyon and Vicinity map area, California. Backscatter data are provided as separate...

  17. BackscatterD [CSUMB Swath]--Monterey Canyon and Vicinity, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the acoustic-backscatter map of Monterey Canyon and Vicinity map area, California. Backscatter data are provided as separate...

  18. Field Plot Points for Canyon De Chelly National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The Canyon de Chelly National Monument Classification Relevé Location executable shapefile (cachplot.exe) was developed as a Geographic Information Systems (GIS)...

  19. Accuracy Assessment Points for Canyon De Chelly National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The Canyon de Chelly National Monument Accuracy Assessment Observation Location executable shapefile (cachaa.exe) was developed as a Geographic Information Systems...

  20. Spatial Vegetation Data for Walnut Canyon National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This metadata is for the vegetation and land-use geo-spatial database for Walnut Canyon National Monument and surrounding areas. The project is authorized as part...

  1. Geology and geomorphology--Monterey Canyon and Vicinity Map Area, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the geologic and geomorphic map of Monterey Canyon and Vicinity, California. The vector data file is included in...

  2. Data Quality Objectives Summary Report for the 221-U Canyon Disposition Alternatives

    International Nuclear Information System (INIS)

    The 221-U Canyon Disposition Alternatives Data Quality Objective (DQO) Process identifies the sampling and analytical requirements necessary to support future detailed evaluation of alternatives via the CERCLA process, for final disposition of the 221-U Canyon Facility. Viable alternatives for the disposition of the 221-U Facility have been identified in a CERCLA Phase I Feasibility Study (FS) (DOE-RL 1997) for the Canyon Disposition Initiative (CDI). The scope of this DQO Process is limited to the 221-U Process Canyon Building and equipment contained within the facility. Associated stacks, filters, solvent handling, vaults, and storage facilities external to the 221-U Building are not addressed in this DQO. This DQO focuses on the 221-U Building because it provides the greatest potential source of contaminant volumes and concentrations and the physical structure poses the greatest challenge for disposition decisions

  3. 76 FR 23335 - Wilderness Stewardship Plan/Environmental Impact Statement, Sequoia and Kings Canyon National...

    Science.gov (United States)

    2011-04-26

    ... proper food storage; party size; camping and campsites; human waste management; stock use; meadow... National Park Service Wilderness Stewardship Plan/Environmental Impact Statement, Sequoia and Kings Canyon... Intent to Prepare Environmental Impact Statement for Wilderness Stewardship Plan, Sequoia and...

  4. Formation of Box Canyon, Idaho, by megaflood: implications for seepage erosion on Earth and Mars.

    Science.gov (United States)

    Lamb, Michael P; Dietrich, William E; Aciego, Sarah M; Depaolo, Donald J; Manga, Michael

    2008-05-23

    Amphitheater-headed canyons have been used as diagnostic indicators of erosion by groundwater seepage, which has important implications for landscape evolution on Earth and astrobiology on Mars. Of perhaps any canyon studied, Box Canyon, Idaho, most strongly meets the proposed morphologic criteria for groundwater sapping because it is incised into a basaltic plain with no drainage network upstream, and approximately 10 cubic meters per second of seepage emanates from its vertical headwall. However, sediment transport constraints, 4He and 14C dates, plunge pools, and scoured rock indicate that a megaflood (greater than 220 cubic meters per second) carved the canyon about 45,000 years ago. These results add to a growing recognition of Quaternary catastrophic flooding in the American northwest, and may imply that similar features on Mars also formed by floods rather than seepage erosion.

  5. 75 FR 27550 - Electrical Interconnection of the Juniper Canyon I Wind Project

    Science.gov (United States)

    2010-05-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Bonneville Power Administration Electrical Interconnection of the Juniper Canyon I Wind Project AGENCY: Bonneville Power Administration (BPA), Department of Energy (DOE). ACTION: Notice of Availability of...

  6. San Bernardino and Leslie Canyon National Wildlife Refuges : Comprehensive Management Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In this CCP for San Bernadino and Leslie Canyons NWRs, an ecosystem approach is adopted to achieve the goals of the refuges over a 15-year timespan. Much emphasis...

  7. Accuracy Assessment Points for Walnut Canyon National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This spatial dataset in ESRI Coverage format maps accuracy assessment point locations for the vegetation map at Walnut Canyon National Monument and in the...

  8. Deepwater Canyons 2012: Pathways to the Abyss on NOAA Ship Nancy Foster between 20120815 and 20121001

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Mid-Atlantic Deep-Water Canyons project is co-funded by the Bureau of Ocean Energy Management (BOEM) and NOAA's Office of Ocean Exploration and Research (which...

  9. The Trail Inventory of Leslie Canyon National Wildlife Refuge [Cycle 1

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of this report is to create a baseline inventory of all non-motorized trails on Leslie Canyon National Wildlife Refuge. Trails in this inventory are...

  10. Water quality and quantity of selected springs and seeps along the Colorado River corridor, Utah and Arizona: Arches National Park, Canyonlands National Park, Glen Canyon National Recreation Area, and Grand Canyon National Park, 1997-98

    Science.gov (United States)

    Taylor, Howard E.; Spence, John R.; Antweiler, Ronald C.; Berghoff, Kevin; Plowman, Terry I.; Peart, Dale B.; Roth, David A.

    2004-01-01

    The U.S. Geological Survey, in cooperation with the National Park Service conducted an intensive assessment of selected springs along the Colorado River Corridor in Arches National Park, Canyonlands National Park, Glen Canyon National Recreation Area, and Grand Canyon National Park in 1997 and 1998, for the purpose of measuring and evaluating the water quality and quantity of the resource. This study was conducted to establish baseline data for the future evaluation of possible effects from recreational use and climate change. Selected springs and seeps were visited over a study period from 1997 to 1998, during which, discharge and on-site chemical measurements were made at selected springs and seeps, and samples were collected for subsequent chemical laboratory analysis. This interdisciplinary study also includes simultaneous studies of flora and fauna, measured and sampled coincidently at the same sites. Samples collected during this study were transported to U.S. Geological Survey laboratories in Boulder, Colorado, where analyses were performed using state-of-the-art laboratory technology. The location of the selected springs and seeps, elevation, geology, aspect, and onsite measurements including temperature, discharge, dissolved oxygen, pH, and specific conductance, were recorded. Laboratory analyses include determinations for alkalinity, aluminum, ammonium (nitrogen), antimony, arsenic, barium, beryllium, bismuth, boron, bromide, cadmium, calcium, cerium, cesium, chloride, chromium, cobalt, copper, dissolved inorganic carbon, dissolved organic carbon, dysprosium, erbium, europium, fluoride, gadolinium, holmium, iodine, iron, lanthanum, lead, lithium, lutetium, magnesium, manganese, mercury, molybdenum, neodymium, nickel, nitrate (nitrogen), nitrite (nitrogen), phosphate, phosphorus, potassium, praseodymium, rhenium, rubidium, samarium, selenium, silica, silver, sodium, strontium, sulfate, tellurium, terbium, thallium, thorium, thulium, tin, titanium, tungsten

  11. Refraction tomography mapping of near-surface dipping layers using landstreamer data at East Canyon Dam, Utah

    Science.gov (United States)

    Ivanov, J.; Miller, R.D.; Markiewicz, R.D.; Xia, J.

    2008-01-01

    We apply the P-wave refraction-tomography method to seismic data collected with a landstreamer. Refraction-tomography inversion solutions were determined using regularization parameters that provided the most realistic near-surface solutions that best matched the dipping layer structure of nearby outcrops. A reasonably well matched solution was obtained using an unusual set of optimal regularization parameters. In comparison, the use of conventional regularization parameters did not provide as realistic results. Thus, we consider that even if there is only qualitative a-priori information about a site (i.e., visual) - in the case of the East Canyon Dam, Utah - it might be possible to minimize the refraction nonuniqueness by estimating the most appropriate regularization parameters.

  12. Colorado Canyons National Conservation Area 2003 visitor use survey: Completion report

    Science.gov (United States)

    Ponds, Phadrea; Gillette, Shana C.; Koontz, Lynne

    2004-01-01

    This report represents the analysis of research conducted by the U.S. Geological Survey (USGS) for the Bureau of Land Management (BLM). The purpose is to provide socio-economic and recreational use information that can be used in the development of a Resource Management Plan (RMP) for the Colorado Canyons National Conservation Area (CCNCA). The results reported here deal primarily with recreation-based activities in four areas: Kokopelli Loops, Rabbit Valley, Loma Boat Launch, and Devil’s Canyon.

  13. Impact of aspect ratio and solar heating on street canyon air temperature

    International Nuclear Information System (INIS)

    The results obtained from RNG (Re-Normalization Group) version of k-and turbulence model are reported in this study. The model is adopted to elucidate the impact of different building aspect ratios (i.e., ratio of building-height-to-street-canyon-width) and solar heating on temperatures in street canyon. The validation of Navier-Stokes and energy an sport equations showed that the model prediction for air-temperature and ambient wind provides reasonable accuracy. The model was applied on AR (Aspect Ratios) one to eight and surface temperature difference (delta and theta/sub s-a/)) of 2 -8. Notably, air-temperatures were higher in high AR street canyons in particular on the leeward side of the street canyon. Further investigation showed that the difference between the air-temperature 'high and low AR street canyons (AR) was positive and high with higher delta and theta/sub s-a/) conversely, the AR become negative and low gradually with lower values of delta and theta(/sub s-a/). These results could be very beneficial for the city and regional planners, civil engineers Id HVAC experts who design street canyons and strive for human thermal comfort with minimum possible energy requirements. (author)

  14. Near-inertial motions in the DeSoto Canyon during Hurricane Georges

    Science.gov (United States)

    Jordi, Antoni; Wang, Dong-Ping; Hamilton, Peter

    2016-09-01

    Hurricane Georges passed directly over an array of 13 moorings deployed in the DeSoto Canyon in the northern Gulf of Mexico on 27-28 September 1998. Current velocity data from the mooring array were analyzed together with a primitive-equation model simulation with realistic hurricane forcing, to characterize the generation and propagation of the hurricane-generated near-inertial waves. The model successfully reproduces the observed mean (sub-inertial) and near-inertial motions. The upper ocean response is strongly impacted by the canyon 'wall': a strong jet is formed along the slope, and the near-inertial motions on the shelf are rapidly suppressed. The model results moreover suggest that strong near-inertial waves in the mixed layer are mostly trapped in an energy flux recirculating gyre around the canyon. This gyre retains the near-inertial energy in the canyon region and enhances the transfer of near-inertial energy below the mixed layer. Additional simulations with idealized topographies show that the presence of a steep slope rather than the canyon is fundamental for the generation of this recirculating gyre. The near-inertial wave energy budget shows that during the study period the wind generated an input of 6.79 × 10-2 Wm-2 of which about 1/3, or 2.43 × 10-2 Wm-2, was transferred below the mixed layer. The horizontal energy flux into and out of the canyon region, in contrast, was relatively weak.

  15. California State Waters Map Series—Monterey Canyon and vicinity, California

    Science.gov (United States)

    Dartnell, Peter; Maier, Katherine L.; Erdey, Mercedes D.; Dieter, Bryan E.; Golden, Nadine E.; Johnson, Samuel Y.; Hartwell, Stephen R.; Cochrane, Guy R.; Ritchie, Andrew C.; Finlayson, David P.; Kvitek, Rikk G.; Sliter, Ray W.; Greene, H. Gary; Davenport, Clifton W.; Endris, Charles A.; Krigsman, Lisa M.; Dartnell, Peter; Cochran, Susan A.

    2016-06-10

    IntroductionIn 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration, interpretation, and visualization of swath bathymetry data, acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles, and bottom-sediment sampling data. The map products display seafloor morphology and character, identify potential marine benthic habitats, and illustrate both the surficial seafloor geology and shallow subsurface geology.The Monterey Canyon and Vicinity map area lies within Monterey Bay in central California. Monterey Bay is one of the largest embayments along the west coast of the United States, spanning 36 km from its northern to southern tips (in Santa Cruz and Monterey, respectively) and 20 km along its central axis. Not only does it contain one of the broadest sections of continental shelf along California’s coast, it also contains Monterey Canyon, one of the largest and deepest submarine canyons in the world. Note that the California’s State Waters limit extends farther offshore between Santa Cruz and Monterey so that it encompasses all of Monterey Bay.The coastal area within the map area is lightly populated. The community of Moss Landing (population, 204) hosts the largest commercial fishing fleet in Monterey Bay in its harbor. The map area also includes parts of the cities of Marina (population, about 20,000) and Castroville (population, about 6,500). Fertile lowlands of the Salinas River and Pajaro River valleys largely occupy the inland part of the map area, and land use is primarily agricultural.The offshore part of the map area lies completely within the Monterey Bay National Marine Sanctuary. The

  16. Macrofaunal Patterns in and around du Couedic and Bonney Submarine Canyons, South Australia.

    Directory of Open Access Journals (Sweden)

    Kathleen E Conlan

    Full Text Available Two South Australian canyons, one shelf-incising (du Couedic and one slope-limited (Bonney were compared for macrofaunal patterns on the shelf and slope that spanned three water masses. It was hypothesized that community structure would (H1 significantly differ by water mass, (H2 show significant regional differences and (H3 differ significantly between interior and exterior of each canyon. Five hundred and thirty-one species of macrofauna ≥ 1 mm were captured at 27 stations situated in depth stratified transects inside and outside the canyons from 100 to 1500 m depth. The macrofauna showed a positive relationship to depth in abundance, biomass, species richness and community composition while taxonomic distinctness and evenness remained high at all depths. Biotic variation on the shelf was best defined by variation in bottom water primary production while sediment characteristics and bottom water oxygen, temperature and nutrients defined biotic variation at greater depth. Community structure differed significantly (p<0.01 among the three water masses (shelf-flowing South Australian current, upper slope Flinders current and lower slope Antarctic Intermediate Water (H1. Although community differences between the du Couedic and Bonney regions were marginally above significance at p = 0.05 (H2, over half of the species captured were unique to each region. This supports the evidence from fish and megafaunal distributions that the du Couedic and Bonney areas are in different bioregions. Overall, the canyon interiors were not significantly different in community composition from the exterior (H3. However, both canyons had higher abundance and/or biomass, increased species dominance, different species composition and coarser sediments near the canyon heads compared to outside the canyons at the same depth (500 m, suggestive of heightened currents within the canyons that influence community composition there. At 1000-1500 m, the canyon interiors were

  17. Large-Eddy Simulation of Ventilation and Pollutant Removal in Neutrally and Unstably Stratified Street Canyons

    Science.gov (United States)

    Liu, C.; Cheng, W.; Leung, D. Y.

    2009-12-01

    Large-eddy simulation model was developed to study the ventilation and pollutant removal of urban street canyons in neutral and unstable stratifications. Street canyons of unity building-height-to-street-width ratio were considered. For the case with unstable stratification, the ground was heated up to a Richardson number Rb (= gh/Uh2(Θh-Θ0)/Θref) of -10, where g is the gravitational acceleration, h the building height, Uh the roof-level velocity scale, Θref the reference temperature, Θh the roof-level temperature and Θ0 the ground temperature. The gaseous pollutant was modeled as a passive scalar. Ground-level area sources with uniform pollutant concentrations were used to model traffic emission. In neutral stratification, skimming flow and poor pollutant removal are observed. A primary recirculation is developed in the street canyon core by the prevalent wind (Fig 1a). It occupies nearly all the space inside the street canyon leaving three small secondary recirculations at the ground-level leeward, ground-level windward and roof-level leeward corners. The pollutant emitted from the street is mostly trapped inside the street canyon hence elevated pollutant concentration is observed. Unstable stratification modifies the flow pattern significantly that enhances the pollutant removal. An enlarged secondary recirculation is observed at the ground-level windward corner (Fig 1b). It pushes the primary recirculation upward which eventually extends over the roof level of street canyon immersing into the shear layer aloft. The sizes of the two small recirculations on the leeward side shrink instead. The wind speed inside the street canyon increases that enhances the pollutant mixing. As a result, the overall pollutant concentration is lower compared with that in neutral stratification. In contrast to a roof-level thin layer of pollutant in neutral stratification, pollutant is carried upward by the convective updraft moving from the building roof level into the shear

  18. Numerical Simulation of Recent Turbidity Currents in the Monterey Canyon System, Offshore California

    Science.gov (United States)

    Heimsund, S.; Xu, J.; Nemec, W.

    2007-12-01

    The method of computational fluid dynamics (CFD) has been used, in the form of a 3D numerical model (Flow- 3D®), to perform a full-scale simulation of turbidity currents measured in December 2002 by three moorings in the Soquel and Monterey canyons. The model was verified by simulation of laboratory flows, and was upscaled to the Monterey Canyon system on the basis of high-resolution bathymetric data and flow measurements. The measured velocity profiles were sufficient to assess the flow thickness, initial velocity and duration in the canyon head zone. A computational grid with a highest feasible resolution was used, and both bathymetry and hydrostatic pressure were accounted for. The volumetric sediment concentration and exact grain- size composition of the flows were unknown, and thus a range of values for the initial concentration and bed roughness were assumed and assessed on a trial-and-error basis. The simulations reveal the behavior of a turbidity current along its descent path, including its local hydraulic characteristics (the 3D field of velocity, sediment concentration, shear stress, strain rate, and dynamic viscosity, as well as the magnitude of velocity and turbulent shear). The results confirm that the velocity structure of turbidity current is highly sensitive to variation in seafloor topography. The December 17th flow in the Soquel Canyon appears to have lost capacity by dilution over a relatively short distance and shown significant velocity fluctuations, which is attributed to the rugged topography of the canyon floor. A major loss of momentum occurred when the flow plunged at high angle into the Monterey Canyon, crashing against its bend's southern wall. The December 20th flow in the Monterey Canyon, in contrast, developed a considerably longer body and strongly accelerated towards the canyon's sharp second bend before crashing against its western wall. The mooring data show a down-canyon decline of velocity and suggest gradual waning, but the

  19. Combining Wind-Tunnel and Field Measurements of Street-Canyon Flow via Stochastic Estimation

    Science.gov (United States)

    Perret, Laurent; Blackman, Karin; Savory, Eric

    2016-06-01

    We demonstrate how application of the stochastic estimation method can be employed to combine spatially well-resolved wind-tunnel particle image velocimetry measurements with instantaneous velocity signals from a limited number of sensors (six sonic anemometers located within the canyon in the present case) to predict full-scale flow dynamics in an entire street-canyon cross-section. The investigated configuration corresponds to a street-canyon flow in a neutrally stratified atmospheric boundary layer with the oncoming flow being perpendicular to the main canyon axis. Data were obtained during both full-scale and 1:200-scale wind-tunnel experiments. The performance of the proposed method is investigated using both wind-tunnel data and signals from five sonic anemometers to predict the velocity from the sixth one. In particular, based on analysis of the influence of the high-frequency velocity fluctuations on the quality of the reconstruction, it is shown that stochastic estimation is able to correctly reproduce the large-scale temporal features of the flow with the present set-up. The full dataset is then used to spatially extrapolate the instantaneous flow measured by the six sonic anemometers and perform detailed analysis of instantaneous flow features. The main features of the flow, such as the presence of the shear layer that develops over the canyon and the intermittent ejection and penetration events across the canyon opening, are well predicted by stochastic estimation. In addition, thanks to the high spatial resolution made possible by the technique, the intermittency of the main vortical structure existing within the canyon is demonstrated, as well as its meandering motion in the canyon cross-section. It is also shown that the canyon flow, particularly its spanwise component, is affected by large-scale fluctuations of low temporal frequency along the canyon axis. Finally, the proposed techniques based on wind-tunnel data can prove useful for a priori

  20. Application of a Lagrangian transport model to organo-mineral aggregates within the Nazaré canyon

    OpenAIRE

    S. Pando; Juliano, M. F.; García, R.; P. A. de Jesus Mendes; Thomsen, L.

    2013-01-01

    In this study, a hydrodynamic model was applied to the Nazaré submarine canyon with boundary forcing provided by an operational forecast model for the west Iberian coast for the spring of 2009. After validation, a lagrangian transport model was coupled to the hydrodynamic model to study and compare the transport patterns of three different classes of organo-mineral aggregates along the Nazaré canyon. The results show that the transport in the canyon is neither constant, nor ...

  1. Preliminary assessment of freshwater crayfish as environmental indicators of human impacts in canyons of the Blue Mountains, Australia

    OpenAIRE

    Hardiman, Nigel; Burgin, Shelley

    2010-01-01

    Canyoning has become a popular recreation activity in the Greater Blue Mountains World Heritage Area (Australia), and park management consider that the activity is having an impact on the local fauna of the fragile canyon ecosystems. Although only limited data exist on the native freshwater crayfish populations that inhabit these canyons, it has been suggested that freshwater crayfish have the potential to act as a rapid bioindicator of human impacts. As a preliminary assessment, we sampled c...

  2. An Investigation of Amphitheater-Headed Canyon Distribution, Morphology Variation, and Longitudinal Profile Controls in Escalante and Tarantula Mesa, Utah.

    Science.gov (United States)

    Ryan, A. J.; Whipple, K. X.

    2014-12-01

    Amphitheater-headed canyons are primarily distinguished from typical fluvial channels by their abrupt headwall terminations. A key goal in the study of river canyons is to establish a reliable link between form and formation processes. This is of particular significance for Mars, where, if such links can be established, amphitheater-headed canyons could be used to determine ancient erosion mechanisms and, by inference, climate conditions. Type examples in arid regions on Earth, such as in Escalante River, Utah, previously have been interpreted as products of groundwater seepage erosion. We investigate amphitheater-headed canyons in Escalante and Tarantula Mesa where variations in canyon head morphology may hold clues for the relative roles of rock properties and fluvial and groundwater processes. In lower Escalante, amphitheaters are only present where canyons have breached the Navajo Sandstone - Kayenta Formation contact. In some canyons, amphitheater development appears to have been inhibited by an abundance of coarse bedload. In Tarantula Mesa, canyons have a variety of headwalls, from amphitheaters to stepped knickzones. Headwall morphology distribution is directly related to the spatially variable presence of knickpoint-forming, fine-grained interbeds within cliff-forming sandstones. Amphitheaters only form where the sandstone unit is undisrupted by these interbeds. Finally, most canyons in Escalante and Tarantula Mesa, regardless of substrate lithology, amphitheater presence, or groundwater spring intensity, are well described by a slope-area power law relationship with regionally constant concavity and normalized steepness indices. This suggests that all channels here are subject to the same erosion rates, independent of groundwater weathering intensity. Thus: 1) variations in canyon headwall form do not necessary relate to differences in fluvial history, 2) stratigraphic variations are clearly of importance in sedimentary canyon systems, and 3) although

  3. Stratigraphic and structural configuration of the Navajo (Jurassic) through Ouray (Mississippian-Devonian) formations in the vicinity of Davis and Lavender Canyons, southeastern Utah

    International Nuclear Information System (INIS)

    This study developed a three-dimensional computer model of stratigraphic and structural relationships within a 3497-km2 (1350-mi2) study area centered on the proposed site for a high-level nuclear waste repository in southeastern Utah. The model consists of a sequence of internally reconciled isopach and structure contour maps horizontally registered and stored in stratigraphic order. This model can be used to display cross sections, perspective block diagrams, or fence diagrams at any orientation; estimate depth of formation contacts and thicknesses for any new stratigraphic or hydrologic boreholes; facilitate ground-water modeling studies; and evaluate the structural and stratigraphic evolution of the study area. This study also includes limited evaluations of aquifer continuity in the Elephant Canyon and Honaker Trail Formations, and of salt dissolution and flowage features as interpreted from geophysical logs. The study identified a long history of movement in the fault system in the north-central part of the study area and a major salt flowage feature in the northeastern part. It describes the Elephant Canyon Formation aquifer as laterally limited, the Honaker Trail Formation aquifer as fairly continuous over the area, and Beef Basin in the southern part of the area as a probable dissolution feature. It also concludes that the Shay-Bridger Jack-Salt Creek Graben system is apparently a vertically continuous feature between the basement and ground surface. No stratigraphic or structural discontinuities were detected in the vicinity of Davis Canyon that appear to be detrimental to the siting of a waste repository

  4. Physical Experiments to Investigate the Effects of Street Bottom Heating and Inflow Turbulence on Urban Street-Canyon Flow

    Institute of Scientific and Technical Information of China (English)

    Jae-Jin KIM; Jong-Jin BAIK

    2005-01-01

    The effects of street bottom heating and inflow turbulence on urban street-canyon flow are experimentally investigated using a circulating water channel. Three experiments are carried out for a street canyon with a street aspect ratio of 1. Results from each experiment with bottom heating or inflow turbulence are compared with those without bottom heating and appreciable inflow turbulence. It is demonstrated that street bottom heating or inflow turbulence increases the intensity of the canyon vortex. A possible explanation on how street bottom heating or inflow turbulence intensifies the canyon vortex is given from a fluid dynamical viewpoint.

  5. Geology of the Red Canyon quadrangle, Montrose county, Colorado

    Science.gov (United States)

    McKay, E.J.; Jobin, D.A.

    1953-01-01

    The Red Canyon quadrangle is one of eighteen 7 1/2-minute quadrangles covering the principal carnotite-producing area of southwestern Colorado. The geology of these quadrangles was mapped by the U.S. Geological Survey for the Atomic Energy Commission as part of a comprehensive study of carnotite deposits. The rocks exposed in the eighteen quadrangles consist of crystalline rocks of pre-Cambrian age and sedimentary rocks that range in age from late Paleozoic to Quaternary. Over much of the area the sedimentary rocks are flat lying, but in places the rocks are disrupted by high-angle faults, and northwest-trending folds. Conspicuous among the folds are large anticlines having cores of intrusive salt and gypsum. Most of the carnotite deposits are confined to the Salt Wash sandstone member of the Jurassic Morrison formation. Within this sandstone, most of the deposits are spottily distributed through an arcuate zone known as the "Uruvan Mineral Belt". Individual deposits range in size from irregular masses containing only a few tons of ore to large, tabular masses containing many thousands of tons. The ore consists largely of sandstone selectively impregnated and in part replaced by uranium and vanadium, minerals. Most of the deposits appear to be related to certain sedimentary structures in sandstones of favorable composition.

  6. That very interesting dance in the Baltimore Canyon

    Energy Technology Data Exchange (ETDEWEB)

    Stuart, A.

    1978-09-11

    Pointing out that offshore oil and gas has been a marginal proposition until now--the only consistent moneymaker being the Federal government as leaser--it is hard to understand the feverish spasms that have swept the stock market for months, at the slightest hint of a discovery in Baltimore Canyon. Despite the dismal returns vs. risks up to the present, most of the oil industry believes it must continue offshore if it wants to stay in the oil and gas business. Most of these oil men widely share the belief that most of the large fields that remain to be discovered are in frontier areas of the continential shelf; and one ''big elephant'' discovered can easily erase a string of losses. Still another reason to keep playing is an astonishing advance in exploration technology known as ''bright spots''. Finally, oil men are lured into the offshore arena by a subtle mixture of perceived necessity, an innate if somewhat battered spirit of optimism, and an unabashed fascination with the game itself--the latter, little understood outside the industry according to Dick Palmer, Texaco's top exploration man, but ''a very interesting dance''.

  7. Shelf break exchange events near the De Soto Canyon

    Science.gov (United States)

    Hamilton, Peter; Speer, Kevin; Snyder, Richard; Wienders, Nicolas; Leben, Robert R.

    2015-11-01

    Observations of currents, temperature, sea-surface height, sea-surface temperature and ocean color, derived from moorings, surface and deep drifters, hydrographic surveys, and satellites, are used to characterize shelf-slope exchange events near the apex of the De Soto Canyon in the northeast Gulf of Mexico. During the winter of 2012-2013, shelf-break time series showed a number of events where cold shelf water extruded over the slope. These events were largely consistent with slope eddies of both signs influencing shelf break currents. Larger-scale circulations, derived from the Loop Current and a separating Loop Current eddy, strongly influenced circulation over the De Soto slope during summer 2012, with flow patterns consistent with potential vorticity conservation over shoaling topography. Statistical investigation into shelf-slope exchange using large numbers of surface drifters indicated that export from the shelf is larger than vice-versa, and is more uniformly distributed along the shelf break. Import onto the shelf appears to favor a region just east of the Mississippi Delta, which is also consistent with the observed onshore transport of surface oil from the Deepwater Horizon disaster.

  8. Pilot RCM application to the Diablo Canyon main stream system

    International Nuclear Information System (INIS)

    In 1986 Pacific Gas ampersand Electric Company (PG ampersand E) became extremely interested in reliability-centered maintenance (RCM) after the initial review of two successful Electric Power Research Institute sponsored projects. RCM was visualized as a methodology to common sensitize the burgeoning preventive maintenance (PM) program at the Diablo Canyon plant. RCM could further the uses of predictive and condition-monitoring techniques, as well as eliminate maintenance on components whose failures were noncritical. An extensive review of maintenance and operation experience data, in conjunction with plant staff recommendations and a prioritization according to maintenance expenditures and operational/safety significance, produced the selected system: the turbine main steam supply system (main steam). The pilot project segmented the main steam system into eight subsystems to aid in analysis: (a) main steam isolation valves, (b) auxiliary feedwater pump turbine, (c) overpressure protection (steam dump), (d) main feedwater pump turbines, (e) main steam, (f) main turbine, (g) steam blowdown, and (h) moisture separator reheaters. System analysis activities, including the preparation of functional failure analyses, failure modes and effects analyses, and logic model analyses, were conducted in parallel with corrective and preventive maintenance data-gathering activities to maximize project team personnel participation during the project. Results and lessons learned are summarized

  9. Effects of building roof greening on air quality in street canyons

    Science.gov (United States)

    Baik, Jong-Jin; Kwak, Kyung-Hwan; Park, Seung-Bu; Ryu, Young-Hee

    2012-12-01

    Building roof greening is a successful strategy for improving urban thermal environment. It is of theoretical interest and practical importance to study the effects of building roof greening on urban air quality in a systematic and quantitative way. In this study, we examine the effects of building roof greening on air quality in street canyons using a computational fluid dynamics (CFD) model that includes the thermodynamic energy equation and the transport equation of passive, non-reactive pollutants. For simplicity, building roof greening is represented by specified cooling. Results for a simple building configuration with a street canyon aspect ratio of one show that the cool air produced due to building roof greening flows into the street canyon, giving rise to strengthened street canyon flow. The strengthened street canyon flow enhances pollutant dispersion near the road, which decreases pollutant concentration there. Thus, building roof greening improves air quality near the road. The degree of air quality improvement near the road increases as the cooling intensity increases. In the middle region of the street canyon, the air quality can worsen when the cooling intensity is not too strong. Results for a real urban morphology also show that building roof greening improves air quality near roads. The degree of air quality improvement near roads due to building roof greening depends on the ambient wind direction. These findings provide a theoretical foundation for constructing green roofs for the purpose of improving air quality near roads or at a pedestrian level as well as urban thermal environment. Further studies using a CFD model coupled with a photochemistry model and a surface energy balance model are required to evaluate the effects of building roof greening on air quality in street canyons in a more realistic framework.

  10. Dense water cascading, bottom currents and sediment wave formation at the exit of the Bari canyon (Southern Adriatic Sea, Italy)

    Science.gov (United States)

    Langone, Leonardo; Miserocchi, Stefano; Boldrin, Alfredo; Turchetto, Margherita; Foglini, Federica; Trincardi, Fabio

    2010-05-01

    IMPACT-09 followed multiple directions: 1) stations along a bathymetric transect and sites studied in previous projects (HERMES, VECTOR, BIOFUN) were re-occupied in order to identify changes of biodiversity and ecosystem functioning; 2) a moored array instrumented with an automatic sediment trap, two current meters, a turbidity sensor and a conductivity and temperature recorder was deployed on the sediment wave field in order to monitor the seasonal variations of food supply and hydrodynamics. Furthermore, a short deployment of the mooring was carried out between 15-24 March, 2009 in order to optimize the position of the instrumented array. Here, we will show the first 6-month results of the mooring experiment, which is planned to last longer than two years. Aims are to verify is the consistence of present-day currents (speed and direction) with respect to the bedforms located at the exit of the canyon. Alternatively, these structures must be considered relict, evidencing past high-energy periods. Unfortunately (at least for this research), winter 2009 was mild and particularly wet. The Po river discharge remained relatively high through all the winter and peaked in late April-early May. Hence, the quantity and the characteristics of the produced NadDW made not likely the occurrence of dense water cascading in the Southern Adriatic. In fact, near-bottom currents at the mooring site were low, never exceeding 20 cm s-1. Currents were generally quasi-parallel to the bedform orientation (~135° N). Nevertheless, during peak periods, the current direction slightly shifted northward, becoming more oblique with respect to the sediment wave crests, the water turbidity showed small amplitude peaks, and the water temperatures recorded the lowest values of the time-series.

  11. Diversity and altitudinal distribution of Chrysomelidae (Coleoptera in Peregrina Canyon, Tamaulipas, Mexico

    Directory of Open Access Journals (Sweden)

    Uriel Jeshua Sánchez-Reyes

    2014-06-01

    Full Text Available The Chrysomelidae (Coleoptera is a highly speciose family that has been poorly studied at the regional level in Mexico. In the present study, we estimated species richness and diversity in oak-pine forest, Tamaulipan thorny scrub and in tropical deciduous forests in Peregrina Canyon within the Altas Cumbres Protected Area of the northeastern state of Tamaulipas, Mexico. Sampling of Chrysomelidae consisted of five sweep net samples (200 net sweeps within each of three sites during four sample periods: early dry season, late dry season, early wet season, and late wet season. Species were identified and total numbers per species were recorded for each sample. A total of 2,226 specimens were collected belonging to six subfamilies, 81 genera and 157 species of Chrysomelidae from the study area. Galerucinae was the most abundant subfamily with 1,828 specimens, representing 82.1% of total abundance in the study area. Lower abundance was recorded in Cassidinae (8.5%, Eumolpinae (3.6%, Cryptocephalinae (2.2%, Chrysomelinae (2.2%, and finally Criocerinae (1.3%. The highest species richness was also presented in the subfamily Galerucinae with 49% of the total obtained species followed by Cassidinae (20%, Cryptocephalinae (9.7%, Eumolpinae (9.7%, Chrysomelinae (6.5% and Criocerinae (5.2%. The most common species were Centralaphthona fulvipennis Jacoby (412 individuals, Centralaphthona diversa (Baly (248, Margaridisa sp.1 (219, Acallepitrix sp.1 (134, Longitarsus sp.1 (104, Heterispa vinula (Erichson (91, Epitrix sp.1 (84 and Chaetocnema sp.1 (72. Twenty-two species were doubletons (1.97% of total abundance and 52 were singletons (2.33%. The estimated overall density value obtained was 0.0037 individuals/m2. The greatest abundance and density of individuals were recorded at the lowest elevation site. However, alpha diversity increased with increasing altitude. Similarity values were less than 50% among the three sites indicating that each site had distinct

  12. Integrated analysis of well logs and seismic data to estimate gas hydrate concentrations at Keathley Canyon, Gulf of Mexico

    Science.gov (United States)

    Lee, M.W.; Collett, T.S.

    2008-01-01

    Accurately detecting and quantifying gas hydrate or free gas in sediments from seismic data require downhole well-log data to calibrate the physical properties of the gas hydrate-/free gas-bearing sediments. As part of the Gulf of Mexico Joint Industry Program, a series of wells were either cored or drilled in the Gulf of Mexico to characterize the physical properties of gas hydrate-bearing sediments, to calibrate geophysical estimates, and to evaluate source and transport mechanisms for gas within the gas hydrates. Downhole acoustic logs were used sparingly in this study because of degraded log quality due to adverse wellbore conditions. However, reliable logging while drilling (LWD) electrical resistivity and porosity logs were obtained. To tie the well-log information to the available 3-D seismic data in this area, a velocity log was calculated from the available resistivity log at the Keathley Canyon 151-2 well, because the acoustic log or vertical seismic data acquired at the nearby Keathley Canyon 151-3 well were either of poor quality or had limited depth coverage. Based on the gas hydrate saturations estimated from the LWD resistivity log, the modified Biot-Gassmann theory was used to generate synthetic acoustic log and a synthetic seismogram was generated with a fairly good agreement with a seismic profile crossing the well site. Based on the well-log information, a faintly defined bottom-simulating reflection (BSR) in this area is interpreted as a reflection representing gas hydrate-bearing sediments with about 15% saturation overlying partially gas-saturated sediments with 3% saturation. Gas hydrate saturations over 30-40% are estimated from the resistivity log in two distinct intervals at 220-230 and 264-300 m below the sea floor, but gas hydrate was not physically recovered in cores. It is speculated that the poor recovery of cores and gas hydrate morphology are responsible for the lack of physical gas hydrate recovery.

  13. Fluctuating helical asymmetry and morphology of snails (Gastropoda in divergent microhabitats at 'Evolution Canyons I and II,' Israel.

    Directory of Open Access Journals (Sweden)

    Shmuel Raz

    Full Text Available BACKGROUND: Developmental instability of shelled gastropods is measured as deviations from a perfect equiangular (logarithmic spiral. We studied six species of gastropods at 'Evolution Canyons I and II' in Carmel and the Galilee Mountains, Israel, respectively. The xeric, south-facing, 'African' slopes and the mesic, north-facing, 'European' slopes have dramatically different microclimates and plant communities. Moreover, 'Evolution Canyon II' receives more rainfall than 'Evolution Canyon I.' METHODOLOGY/PRINCIPAL FINDINGS: We examined fluctuating asymmetry, rate of whorl expansion, shell height, and number of rotations of the body suture in six species of terrestrial snails from the two 'Evolution Canyons.' The xeric 'African' slope should be more stressful to land snails than the 'European' slope, and 'Evolution Canyon I' should be more stressful than 'Evolution Canyon II.' Only Eopolita protensa jebusitica showed marginally significant differences in fluctuating helical asymmetry between the two slopes. Contrary to expectations, asymmetry was marginally greater on the 'European' slope. Shells of Levantina spiriplana caesareana at 'Evolution Canyon I,' were smaller and more asymmetric than those at 'Evolution Canyon II.' Moreover, shell height and number of rotations of the suture were greater on the north-facing slopes of both canyons. CONCLUSIONS/SIGNIFICANCE: Our data is consistent with a trade-off between drought resistance and thermoregulation in snails; Levantina was significantly smaller on the 'African' slope, for increasing surface area and thermoregulation, while Eopolita was larger on the 'African' slope, for reducing water evaporation. In addition, 'Evolution Canyon I' was more stressful than Evolution Canyon II' for Levantina.

  14. A Laboratory Model for the Flow in Urban Street Canyons Induced by Bottom Heating

    Institute of Scientific and Technical Information of China (English)

    刘辉志; 梁彬; 朱凤荣; 张伯寅; 桑建国

    2003-01-01

    Water tank experiments are carried out to investigate the convection flow induced by bottom heating and the effects of the ambient wind on the flow in non-symmetrical urban street canyons based on the PIV (Particle Image Visualization) technique. Fluid experiments show that with calm ambient wind,the flows in the street canyon are completely driven by thermal force, and the convection can reach the upper atmosphere of the street canyon. Horizontal and vertical motions also appear above the roofs of the buildings. These are the conditions which favor the exchange of momentum and air mass between the street canyon and its environment. More than two vortices are induced by the convection, and the complex circulation pattern will vary with time in a wider street canyon. However, in a narrow street canyon, just one vortex appears. With a light ambient wind, the bottom heating and the associated convection result in just one main vortex. As the ambient wind speed increases, the vortex becomes more organized and its center shifts closer to the leeward building.

  15. A review of the role of submarine canyons in deep-ocean exchange with the shelf

    Directory of Open Access Journals (Sweden)

    S. E. Allen

    2009-12-01

    Full Text Available Cross shelf-break exchange is limited by the tendency of geostrophic flow to follow bathymetric contours, not cross them. However, small scale topography, such as canyons, can reduce the local lengthscale of the flow and increase the local Rossby number. These higher Rossby numbers mean the flow is no longer purely geostrophic and significant cross-isobath flow can occur. This cross-isobath flow includes both upwelling and downwelling due to wind-driven shelf currents and the strong cascading flows of dense shelf-water into the ocean. Tidal currents usually run primarily parallel to the shelf-break topography. Canyons cut across these flows and thus are often regions of generation of strong baroclinic tides and internal waves. Canyons can also focus internal waves. Both processes lead to greatly elevated levels of mixing. Thus, through both advection and mixing processes, canyons can enhance Deep Ocean Shelf Exchange. Here we review the state of the science describing the dynamics of the flows and suggest further areas of research, particularly into quantifying fluxes of nutrients and carbon as well as heat and salt through canyons.

  16. Numerical Study of Traffic Pollutant Dispersion within Different Street Canyon Configurations

    Directory of Open Access Journals (Sweden)

    Yucong Miao

    2014-01-01

    Full Text Available The objective of this study is to numerically study flow and traffic exhaust dispersion in urban street canyons with different configurations to find out the urban-planning strategies to ease the air pollution. The Computational Fluid Dynamics (CFD model used in this study—Open Source Field Operation and Manipulation (OpenFOAM software package—was firstly validated against the wind-tunnel experiment data by using three different k-ε turbulence models. And then the patterns of flow and dispersion within three different kinds of street canyon configuration under the perpendicular approaching flow were numerically studied. The result showed that the width and height of building can dramatically affect the pollution level inside the street canyon. As the width or height of building increases, the pollution at the pedestrian level increases. And the asymmetric configuration (step-up or step-down street canyon could provide better ventilation. It is recommended to design a street canyon with nonuniform configurations. And the OpenFOAM software package can be used as a reliable tool to study flows and dispersions around buildings.

  17. On the Impact of Trees on Dispersion Processes of Traffic Emissions in Street Canyons

    Science.gov (United States)

    Gromke, Christof; Ruck, Bodo

    2009-04-01

    Wind-tunnel studies of dispersion processes of traffic exhaust in urban street canyons with tree planting were performed and tracer gas concentrations using electron capture detection (ECD) and flow fields using laser Doppler velocimetry (LDV) were measured. It was found that tree planting reduces the air exchange between street canyons and the ambience. In comparison to treeless street canyons, higher overall pollutant concentrations and lower flow velocities were measured. In particular, for perpendicular approaching wind, markedly higher concentrations at the leeward canyon wall and slightly lower concentrations at the windward canyon wall were observed. Furthermore, a new approach is suggested to model porous vegetative structures such as tree crowns for small-scale wind-tunnel applications. The approach is based on creating different model tree crown porosities by incorporating a certain amount of wadding material into a specified volume. A significant influence of the crown porosity on pollutant concentrations was found for high degrees of porosity, however, when it falls below a certain threshold, no further changes in pollutant concentrations were observed.

  18. Street canyon flow patterns in a horizontal plane : measurements from the Joint URBAN 2003 field experiment

    Energy Technology Data Exchange (ETDEWEB)

    Brown, M. J. (Michael J.); Khalsa, H. S. (Hari S.); Nelson, M. A. (Matthew Aaron); Boswell, D. (David)

    2004-01-01

    As part of the larger Joint URBAN 2003 tracer field experiment performed in Oklahoma City from June 29 to July 30, 2003, a collaborative team of government and university researchers instrumented a downtown street canyon with a high density of wind sensor instrumentation (Brown et al., 2003). The goal of the Park Avenue street canyon experiment was to garner flow field information in order to better understand the transport and dispersion of tracers released in the street canyon and to test and improve the next generation of urban dispersion models. In this paper, we focus on describing the mean flow patterns that developed in the street canyon in a horizontal plane near the surface. We look at the patterns that develop over entire Intensive Operating Periods (IOP's) lasting from 6-9 hours in length, and as a function of inflow wind direction. Most prior street canyon experiments have generally focused on the vertical structure of the flow; this work contributes to the understanding of the horizontal nature of the flow.

  19. Characterising the pollutant ventilation characteristics of street canyons using the tracer age and age spectrum

    Science.gov (United States)

    Lo, K. W.; Ngan, K.

    2015-12-01

    The age of air, which measures the time elapsed between the emission of a chemical constituent and its arrival at a receptor location, has many applications in urban air quality. Typically it has been estimated for special cases, e.g. the local mean age of air for a spatially homogeneous source. An alternative approach uses the response to a point source to determine the distribution of transit times or tracer ages connecting the source and receptor. The distribution (age spectrum) and first moment (mean tracer age) have proven to be useful diagnostics in stratospheric modelling because they can be related to observations and do not require a priori assumptions. The tracer age and age spectrum are applied to the pollutant ventilation of street canyons in this work. Using large-eddy simulations of flow over a single isolated canyon and an uneven, non-uniform canyon array, it is shown that the structure of the tracer age is dominated by the central canyon "vortex"; small variations in the building height have a significant influence on the structure of the tracer age and the pollutant ventilation. The age spectrum is broad, with a long exponential tail whose slope depends on the canyon geometry. The mean tracer age, which roughly characterises the ventilation strength, is much greater than the local mean age of air.

  20. Fault tree analysis of Project S-4404, Upgrade Canyon Exhaust System

    International Nuclear Information System (INIS)

    Project S-4404, Upgrade Canyon Exhaust Systems, is a $177 million project with the purpose of upgrading the Exhaust Systems for both F and H Canyon Facilities. This upgrade will replace major portions of the F and H-Canyon exhaust systems, downstream of their respective sand filters with higher capacity and more reliable systems. Because of the high cost, DOE requested Program Control ampersand Integration (PC ampersand I) to examine specific deletions to the project. PC ampersand I requested Nuclear Processes Safety Research (NPSR) to perform an analysis to compare failure rates for the existing F ampersand H Canyon exhaust systems with the proposed exhaust system and specific proposed exhaust system alternatives. The objective of this work was to perform an analysis and compare failure rates for the existing F ampersand H Canyon exhaust systems with the proposed project exhaust system and proposed project alternatives. Based on fault tree analysis, two conclusions are made. First, D ampersand D activities can be eliminated from the project with no significant decrease to exhaust system safety. Deletion of D ampersand D activities would result in a cost savings of $29 million. Second, deletion of DOE Order 6430.1A requirements regarding DBAs would decrease exhaust system safety by a factor of 12

  1. Macroinvertebrate diets reflect tributary inputs and turbidity-driven changes in food availability in the Colorado River downstream of Glen Canyon Dam

    Science.gov (United States)

    Wellard Kelly, Holly A.; Rosi-Marshall, Emma J.; Kennedy, Theodore A.; Hall, Robert O., Jr.; Cross, Wyatt F.; Baxter, Colden V.

    2013-01-01

    Physical changes to rivers associated with large dams (e.g., water temperature) directly alter macroinvertebrate assemblages. Large dams also may indirectly alter these assemblages by changing the food resources available to support macroinvertebrate production. We examined the diets of the 4 most common macroinvertebrate taxa in the Colorado River through Glen and Grand Canyons, seasonally, at 6 sites for 2.5 y. We compared macroinvertebrate diet composition to the composition of epilithon (rock and cliff faces) communities and suspended organic seston to evaluate the degree to which macroinvertebrate diets tracked downstream changes in resource availability. Diets contained greater proportions of algal resources in the tailwater of Glen Canyon Dam and more terrestrial-based resources at sites downstream of the 1st major tributary. As predicted, macroinvertebrate diets tracked turbidity-driven changes in resource availability, and river turbidity partially explained variability in macroinvertebrate diets. The relative proportions of resources assimilated by macroinvertebrates ranged from dominance by algae to terrestrial-based resources, despite greater assimilation efficiencies for algal than terrestrial C. Terrestrial resources were most important during high turbidity conditions, which occurred during the late-summer monsoon season (July–October) when tributaries contributed large amounts of organic matter to the mainstem and suspended sediments reduced algal production. Macroinvertebrate diets were influenced by seasonal changes in tributary inputs and turbidity, a result suggesting macroinvertebrate diets in regulated rivers may be temporally dynamic and driven by tributary inputs.

  2. Water-quality conditions near the confluence of the Snake and Boise Rivers, Canyon County, Idaho

    Science.gov (United States)

    Wood, Molly S.; Etheridge, Alexandra

    2011-01-01

    Total Maximum Daily Loads (TMDLs) have been established under authority of the Federal Clean Water Act for the Snake River-Hells Canyon reach, on the border of Idaho and Oregon, to improve water quality and preserve beneficial uses such as public consumption, recreation, and aquatic habitat. The TMDL sets targets for seasonal average and annual maximum concentrations of chlorophyll-a at 14 and 30 micrograms per liter, respectively. To attain these conditions, the maximum total phosphorus concentration at the mouth of the Boise River in Idaho, a tributary to the Snake River, has been set at 0.07 milligrams per liter. However, interactions among chlorophyll-a, nutrients, and other key water-quality parameters that may affect beneficial uses in the Snake and Boise Rivers are unknown. In addition, contributions of nutrients and chlorophyll-a loads from the Boise River to the Snake River have not been fully characterized. To evaluate seasonal trends and relations among nutrients and other water-quality parameters in the Boise and Snake Rivers, a comprehensive monitoring program was conducted near their confluence in water years (WY) 2009 and 2010. The study also provided information on the relative contribution of nutrient and sediment loads from the Boise River to the Snake River, which has an effect on water-quality conditions in downstream reservoirs. State and site-specific water-quality standards, in addition to those that relate to the Snake River-Hells Canyon TMDL, have been established to protect beneficial uses in both rivers. Measured water-quality conditions in WY2009 and WY2010 exceeded these targets at one or more sites for the following constituents: water temperature, total phosphorus concentrations, total phosphorus loads, dissolved oxygen concentration, pH, and chlorophyll-a concentrations (WY2009 only). All measured total phosphorus concentrations in the Boise River near Parma exceeded the seasonal target of 0.07 milligram per liter. Data collected

  3. Bell Canyon Test (BCT) cement grout development report

    International Nuclear Information System (INIS)

    Development of the cement grout for the Bell Canyon Test was accomplished at the US Army Engineer Waterways Experiment Station (WES), Vicksburg, Mississippi. Initial development work centered on a saltwater grout with Class H cement, fly ash, and an expansive additive. Testing of the saltwater grout showed suitable properties except for the interface between anhydrite rock and grout in small core samples. Higher than expected permeability occurred at the interface because of space between the grout and the anhydrite; the space was produced as a result of allowing the specimens to dry. A change to freshwater grout and proper care to prevent the specimens from drying alleviated this condition. The BCT-1FF freshwater grout mixture was used in both the plug ONE and ONEX field grouting operations. Testing of the development grout mixtures was also done at Dowell, Pennsylvania State University, and Oak Ridge National Laboratory. Results of the testing and evaluation by the four laboratories are included in the report. Field batching, mixing, and placement of the grout at the plug locations for both plug ONE and ONEX were satisfactory with adequate quality control. The freshwater grout mixture maintained adequate flow characteristics for pumpability for 3 1/2 h during each of the two field operations. Physical property and expansivity data for the field samples through 90 days' age are in general agreement with laboratory development data. A large number of samples were obtained for inclusion in the long-term durability studies and the geochemical programs. The high-density, low water-cement ratio expansive grout (BCT-1FF) is considered to be an excellent candidate for plugging boreholes at most locations

  4. Seismic stratigraphy of northern Green Canyon area, Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Mann, R.G.; Bryant, W.R.

    1986-05-01

    The Green Canyon area of the Gulf of Mexico is an active frontier exploration area of the continental slope underlain by relatively shallow salt or shale diapirs and ridges forming large intraslope basins and troughs. Analysis of more than 200 multichannel seismic profiles in this area show several seismic sequences within each basin or trough. The depositional history of the area is interpreted from the seismic sequences and seismic facies distribution within each basin. These facies are based on reflection configuration and include parallel to subparallel reflections, prograding clinoforms, hummocky clinoforms, chaotic zones, and acoustically semitransparent zones. Sigmoid and oblique progradational clinoforms are found at the shelf edge where outbuilding and aggradation occur. Hummocky clinoforms are widespread in each basin and occur in thick sequences. These grade vertically and laterally into parallel or semitransparent zones resulting in alternating reflection patterns. The parallel reflections can be interpreted as low-energy turbidites deposited during lower sea level. Chaotic zones show contorted stratal surfaces suggesting mass movement deposits. The evolution of each basin is unique. Structure and isopach maps of each sequence along with the facies distribution indicate several depositional mechanisms. These are possibly related to sea level fluctuations and shifting sediment supply. Correlation of sequences between basins and troughs is hampered in the western half of the area because of the presence of shallow subsurface diapirs and ridges, and large growth faults, and the absence of well data. Diapirs in the eastern half are less numerous and more isolated, with thicker sedimentary troughs between them because of the eastward migration of the Mississippi fan across this area in the Pliocene and Pleistocene.

  5. Sympatric speciation of spiny mice, Acomys, unfolded transcriptomically at Evolution Canyon, Israel.

    Science.gov (United States)

    Li, Kexin; Wang, Huihua; Cai, Zhenyuan; Wang, Liuyang; Xu, Qinqin; Lövy, Matěj; Wang, Zhenlong; Nevo, Eviatar

    2016-07-19

    Spiny mice, Acomys cahirinus, colonized Israel 30,000 y ago from dry tropical Africa and inhabited rocky habitats across Israel. Earlier, we had shown by mtDNA that A. cahirinus incipiently sympatrically speciates at Evolution Canyon I (EC I) in Mount Carmel, Israel because of microclimatic interslope divergence. The EC I microsite consists of a dry and hot savannoid "African" slope (AS) and an abutting humid and cool-forested "European" slope (ES). Here, we substantiate incipient SS in A. cahirinus at EC I based on the entire transcriptome, showing that multiple slope-specific adaptive complexes across the transcriptome result in two divergent clusters. Tajima's D distribution of the abutting Acomys interslope populations shows that the ES population is under stronger positive selection, whereas the AS population is under balancing selection, harboring higher genetic polymorphisms. Considerable sites of the two populations were differentiated with a coefficient of FST = 0.25-0.75. Remarkably, 24 and 37 putatively adaptively selected genes were detected in the AS and ES populations, respectively. The AS genes involved DNA repair, growth arrest, neural cell differentiation, and heat-shock proteins adapting to the local AS stresses of high solar radiation, drought, and high temperature. In contrast, the ES genes involved high ATP associated with energetics stress. The sharp ecological interslope divergence led to strong slope-specific selection overruling the interslope gene flow. Earlier tests suggested slope-specific mate choice. Habitat interslope-adaptive selection across the transcriptome and mate choice substantiate sympatric speciation (SS), suggesting its prevalence at EC I and commonality in nature. PMID:27370801

  6. High resolution Holocene sea ice records from Herald Canyon, Chukchi Sea

    Science.gov (United States)

    Pearce, Christof; Jakobsson, Martin; O'Regan, Matt; Rattray, Jayne; Barrientos, Natalia; Muchitiello, Francesco; Smittenburg, Rienk; Cronin, Tom; Coxall, Helen; Semiletov, Igor

    2016-04-01

    Arctic Ocean sea ice plays a critical role in the Earth's climate system because of the positive ice-albedo feedback mechanisms as well as its control on ocean-atmospheric heat exchange and potential influence on the thermohaline circulation. Key to improving our understanding of Arctic sea ice cover and its reaction to external forcing is the reconstruction of past variability through paleo-records such as marine sediment cores. Although the observed recent sea ice loss seems to be the strongest of the last millennia, it is still uncertain whether the shift from perennial to seasonal ice cover expected for the near future was unprecedented during the current interglacial. High resolution sea ice reconstructions from the Arctic Ocean are rare, and specifically records from the Russian Arctic are underrepresented. In this study, we present results from marine sediment cores from the Herald Canyon in the East Siberian Sea. The area is one of the major conduits of Pacific water entering the Arctic Ocean basin from the Bering Strait and is thus an ideal place to study past variability of the inflow of these nutrient rich waters. Radiocarbon dating of mollusks indicates very high sedimentation rates at the coring sites which allowed for analyses at centennial resolution up to decadal resolution in the late Holocene. Core samples were analyzed for the biomarker IP25, which is produced by diatoms living in sea ice and is used as a proxy of past seasonal sea ice concentrations. Preliminary results indicate the presence of seasonal sea ice during the entire Late Holocene and show a significant increase of sea ice concentrations during the last millennia.

  7. High resolution Holocene sea ice records from Herald Canyon, East Siberian Sea

    Science.gov (United States)

    Pearce, C.; Rattray, J.; Jakobsson, M.; Barrientos, N.; Muschitiello, F.; Smittenberg, R.; O'Regan, M.; Coxall, H.

    2015-12-01

    Arctic Ocean sea ice plays a critical role in the Earth's climate system because of the positive ice-albedo feedback mechanisms as well as its control on ocean-atmospheric heat exchange and potential influence on the thermohaline circulation. Key to improving our understanding of Arctic sea ice cover and its reaction to external forcing is the reconstruction of past variability through paleo-records such as marine sediment cores. Although the observed recent sea ice loss seems to be the strongest of the last millennia, it is still uncertain whether the shift from perennial to seasonal ice cover expected for the near future was unprecedented during the current interglacial. High resolution sea ice reconstructions from the Arctic Ocean are rare, and specifically records from the Russian Arctic are underrepresented. In this study, we present results from marine sediment cores from the Herald Canyon in the East Siberian Sea. The area is one of the major conduits of Pacific water entering the Arctic Ocean basin from the Bering Strait and is thus an ideal place to study past variability of the inflow of these nutrient rich waters. Radiocarbon dating of mollusks indicates very high sedimentation rates at the coring sites which allowed for analyses at centennial resolution up to decadal resolution in the late Holocene. Core samples were analyzed for the biomarker IP25, which is produced by diatoms living in sea ice and is used as a proxy of past seasonal sea ice concentrations. Preliminary results indicate the presence of seasonal sea ice during the entire Late Holocene and show a significant increase of sea ice concentrations during the last millennia.

  8. Parasites of native and nonnative fishes of the Little Colorado River, Grand Canyon, Arizona

    Science.gov (United States)

    Choudhury, A.; Hoffnagle, T.L.; Cole, R.A.

    2004-01-01

    A 2-yr, seasonal, parasitological study of 1,435 fish, belonging to 4 species of native fishes and 7 species of nonnative fishes from the lower Little Colorado River (LCR) and tributary creeks, Grand Canyon, Arizona, yielded 17 species of parasites. These comprised 1 myxozoan (Henneguya exilis), 2 copepods (Ergasilus arthrosis and Lernaea cyprinacea), 1 acarine (Oribatida gen. sp.), 1 piscicolid leech (Myzobdella lugubris), 4 monogeneans (Gyrodactylus hoffmani, Gyrodactylus sp., Dactylogyrus extensus, and Ligictaluridus floridanus), 4 nematodes (Contracaecum sp., Eustrongylides sp., Rhabdochona sp., and Truttaedacnitis truttae), 3 cestodes (Bothriocephalus acheilognathi, Corallobothrium fimbriatum, and Megathylacoides giganteum), and 2 trematodes (Ornithodiplostomum sp. and Posthodiplostomum sp.). Rhabdochona sp. was the only adult parasite native to the LCR. Infection intensities of Ornithodiplostomum sp. and B. acheilognathi were positively correlated with length of the humpback chub Gila cypha. Adult helminths showed a high degree of host specificity, except B. acheilognathi, which was recovered from all fish species examined but was most abundant in cyprinids. Abundance of B. acheilognathi in the humpback chub was highest in the fall and lowest in the summer in both reaches of the LCR. There was no major taxonomic difference in parasite assemblages between the 2 different reaches of the river (LC1 and LC2). Parasite community diversity was very similar in humpback chub, regardless of sampling site or time. The parasite fauna of the LCR is numerically dominated by B. acheilognathi and metacercariae of Ornithodiplostomum sp. The richest and most diverse component community occurred in a nonnative species, the channel catfish Ictalurus punctatus, but infracommunity species richness was highest in a native host, humpback chub.

  9. Final Technical Report - Modernization of the Boulder Canyon Hydroelectric Project

    Energy Technology Data Exchange (ETDEWEB)

    Taddeucci, Joe [Dept. of Public Works, Boulder, CO (United States). Utilities Division

    2013-03-29

    The Boulder Canyon Hydroelectric Project (BCH) was purchased by the City of Boulder, CO (the city) in 2001. Project facilities were originally constructed in 1910 and upgraded in the 1930s and 1940s. By 2009, the two 10 MW turbine/generators had reached or were nearing the end of their useful lives. One generator had grounded out and was beyond repair, reducing plant capacity to 10 MW. The remaining 10 MW unit was expected to fail at any time. When the BCH power plant was originally constructed, a sizeable water supply was available for the sole purpose of hydroelectric power generation. Between 1950 and 2001, that water supply had gradually been converted to municipal water supply by the city. By 2001, the water available for hydroelectric power generation at BCH could not support even one 10 MW unit. Boulder lacked the financial resources to modernize the facilities, and Boulder anticipated that when the single, operational historical unit failed, the project would cease operation. In 2009, the City of Boulder applied for and received a U.S. Department of Energy (DOE) grant for $1.18 million toward a total estimated project cost of $5.155 million to modernize BCH. The federal funding allowed Boulder to move forward with plant modifications that would ensure BCH would continue operation. Federal funding was made available through the American Recovery and Reinvestment Act (ARRA) of 2009. Boulder determined that a single 5 MW turbine/generator would be the most appropriate capacity, given the reduced water supply to the plant. Average annual BCH generation with the old 10 MW unit had been about 8,500 MW-hr, whereas annual generation with a new, efficient turbine could average 11,000 to 12,000 MW-hr. The incremental change in annual generation represents a 30% increase in generation over pre-project conditions. The old turbine/generator was a single nozzle Pelton turbine with a 5-to-1 flow turndown and a maximum turbine/generator efficiency of 82%. The new unit is a

  10. Effects of stock use and backpackers on water quality in wilderness in Sequoia and Kings Canyon National Parks, USA

    Science.gov (United States)

    Clow, David W.; Forrester, Harrison; Miller, Benjamin; Roop, Heidi; Sickman, James O.; Ryu, Hodon; Santo Domingo, Jorge

    2013-01-01

    During 2010-2011, a study was conducted in Sequoia and Kings Canyon National Parks (SEKI) to evaluate the influence of pack animals (stock) and backpackers on water quality in wilderness lakes and streams. The study had three main components: (1) a synoptic survey of water quality in wilderness areas of the parks, (2) paired water-quality sampling above and below several areas with differing types and amounts of visitor use, and (3) intensive monitoring at six sites to document temporal variations in water quality. Data from the synoptic water-quality survey indicated that wilderness lakes and streams are dilute and have low nutrient and Escherichia coli (E. coli) concentrations. The synoptic survey sites were categorized as minimal use, backpacker use, or mixed use (stock and backpackers), depending on the most prevalent type of use upstream from the sampling locations. Sites with mixed use tended to have higher concentrations of most constituents (including E.coli) than those categorized as minimal-use (p≤0.05); concentrations at backpacker-use sites were intermediate. Data from paired-site sampling indicated that E.coli, total coliform, and particulate phosphorus concentrations were greater in streams downstream from mixed-use areas than upstream from those areas (p≤0.05). Paired-site data also indicated few statistically significant differences in nutrient, E. coli, or total coliform concentrations in streams upstream and downstream from backpacker-use areas. The intensive-monitoring data indicated that nutrient and E. coli concentrations normally were low, except during storms, when notable increases in concentrations of E.coli, nutrients, dissolved organic carbon, and turbidity occurred. In summary, results from this study indicate that water quality in SEKI wilderness generally is good, except during storms; and visitor use appears to have a small, but statistically significant influence on stream water quality.

  11. 77 FR 55829 - Western Area Power Administration; Grapevine Canyon Wind Project Record of Decision (DOE/EIS-0427)

    Science.gov (United States)

    2012-09-11

    ... Area Power Administration; Grapevine Canyon Wind Project Record of Decision (DOE/EIS-0427) AGENCY... Grapevine Canyon Wind Project was published in the Federal Register (77 FR 34041). After considering the... proposed wind park would be built in one or more phases, dependent on one or more power sale contracts....

  12. 75 FR 18201 - Juniper Canyon Wind Power, LLC; Supplemental Notice That Initial Market-Based Rate Filing...

    Science.gov (United States)

    2010-04-09

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Juniper Canyon Wind Power, LLC; Supplemental Notice That Initial Market... supplemental notice in the above-referenced proceeding of Juniper Canyon Wind Power, LLC's application...

  13. 76 FR 9347 - Coyote Canyon Energy LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes...

    Science.gov (United States)

    2011-02-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Coyote Canyon Energy LLC; Supplemental Notice That Initial Market-Based Rate...-referenced proceeding of Coyote Canyon Energy LLC's application for market-based rate authority, with...

  14. 77 FR 32625 - William J. Stevenson, Estate of Lynn E. Stevenson, Black Canyon Bliss, LLC; Notice of Application...

    Science.gov (United States)

    2012-06-01

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission William J. Stevenson, Estate of Lynn E. Stevenson, Black Canyon Bliss, LLC... 23, 2012, William J. Stevenson, Estate of Lynn E. Stevenson (transferor) and Black Canyon Bliss,...

  15. 77 FR 61790 - Pacific Gas and Electric; Diablo Canyon Power Plant, Units 1 and 2; Application for Amendment to...

    Science.gov (United States)

    2012-10-11

    ... COMMISSION Pacific Gas and Electric; Diablo Canyon Power Plant, Units 1 and 2; Application for Amendment to... Gas and Electric (the licensee) to withdraw its application dated October 24, 2011 (ADAMS Accession No... amendment to Facility Operating License Nos. DPR-80 and DPR-82 for the Diablo Canyon Power Plant, Units...

  16. 75 FR 54920 - In the Matter of Pacific Gas & Electric Company (Diablo Canyon Nuclear Power Plant, Units 1 and 2...

    Science.gov (United States)

    2010-09-09

    ... COMMISSION In the Matter of Pacific Gas & Electric Company (Diablo Canyon Nuclear Power Plant, Units 1 and 2... proceeding concerns the November 23, 2009, application of Pacific Gas & Electric Company (PG&E) to renew Operating License Nos. DPR-80 and DPR-82 for the Diablo Canyon Nuclear Power Plant, Units 1 and 2, near...

  17. 76 FR 37843 - Pacific Gas and Electric Company, Diablo Canyon Power Plant, Unit 1 and 2; Exemption

    Science.gov (United States)

    2011-06-28

    ... COMMISSION Pacific Gas and Electric Company, Diablo Canyon Power Plant, Unit 1 and 2; Exemption 1.0 Background Pacific Gas and Electric Company (PG&E, the licensee) is the holder of Facility Operating License Nos. DPR-80 and DPR-82, which authorize operation of the Diablo Canyon Power Plant, Unit 1 and 2...

  18. 76 FR 23807 - Blue Canyon Windpower VI LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes...

    Science.gov (United States)

    2011-04-28

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Blue Canyon Windpower VI LLC; Supplemental Notice That Initial Market-Based... above-referenced proceeding of Blue Canyon Windpower VI LLC's application for market-based...

  19. 75 FR 26788 - Public Land Order No. 7742; Withdrawal of Public Land for the Manning Canyon Tailings Repository; UT

    Science.gov (United States)

    2010-05-12

    ... Tailings Repository; UT AGENCY: Bureau of Land Management, Interior. ACTION: Public Land Order. SUMMARY... laws for a period of 5 years to protect the integrity of the Manning Canyon Tailings Repository and... Canyon Tailings Repository. The Bureau of Land Management intends to evaluate the need for a...

  20. A study on soil–structure interaction analysis in canyon-shaped topographies

    Indian Academy of Sciences (India)

    Oguz Akin Duzgun; Ahmet Budak

    2010-06-01

    In this paper, a coupled finite and infinite element system is used to study the effects of canyon-shaped topography and geotechnical characteristics of the soil on the dynamic response of free surface and of 2- soil–structure systems under ground motion. A parametric study is carried out for canyon-shaped topographies. It is concluded that topographic conditions may have important effects on the ground motion along the canyon. Geotechnical properties of the soil also have significant amplification effects on the whole system motion, which cannot be neglected for design purposes. Thus, the dynamic response of both free surface and a soil–structure system are primarily affected by surface shapes and geotechnical properties of the soil. Location of the structure is another parameter affecting the whole system response.

  1. Characterization of a shallow canyon aquifer contaminated by mine tailings and suggestions for constructed wetlands treatment

    International Nuclear Information System (INIS)

    A shallow aquifer consisting of mine tailings mixed with alluvial sediments is being investigated by the University of Idaho. The shallow aquifer is located in the lower Canyon Creek drainage in the Coeur d'Alene Mining District of northern Idaho. Canyon Creek is a major contributor of dissolved heavy metal loads to the South Fork of the Coeur d'Alene River. Problem metals include zinc, lead, and cadmium. A total of 16 new monitoring wells were constructed in a 2.5 by .5 mile study area during summer of 1993 to map the water table configuration and collect water samples. A monitoring network of wells have been established in the Lower Canyon Creek valley which includes these 16 new monitoring wells, 5 monitoring wells installing previously, 10 domestic wells, and 7 wells located near tailing ponds. Water quality analyses for ground and surface water samples collected during low creek flow conditions are presented along with geologic, geophysical and geohydrological information

  2. Heavy mineral sorting in downwards injected Palaeocene sandstone, Siri Canyon, Danish North Sea

    DEFF Research Database (Denmark)

    Kazerouni, Afsoon Moatari; Friis, Henrik; Svendsen, Johan Byskov;

    2011-01-01

    Post-depositional remobilization and injection of sand are often seen in deep-water clastic systems and has been recently recognised as a significant modifier of deep-water sandstone geometry. Large-scale injectite complexes have been interpreted from borehole data in the Palaeocene Siri Canyon...... of depositional structures in deep-water sandstones, the distinction between "in situ" and injected or remobilised sandstones is often ambiguous. Large scale heavy mineral sorting (in 10 m thick units) is observed in several reservoir units in the Siri Canyon and has been interpreted to represent the depositional...... sorting. In this study we describe an example of effective shear-zone sorting of heavy minerals in a thin downward injected sandstone dyke which was encountered in one of the cores in the Cecilie Field, Siri Canyon. Differences in sorting pattern of heavy minerals are suggested as a tool for petrographic...

  3. Numerical Studies on Flow Fields Around Buildings in an Urban Street Canyon and Cross-Road

    Institute of Scientific and Technical Information of China (English)

    CHENG Xueling; HU Fei

    2005-01-01

    The questions on how vortices are constructed and on the relationship between the flow patterns and concentration distributions in real street canyons are the most pressing questions in pollution control studies. In this paper, the very large eddy simulation (VLES) and large eddy simulation (LES) are applied to calculate the flow and pollutant concentration fields in an urban street canyon and a cross-road respectively. It is found that the flow separations are not only related to the canyon aspect ratios, but also with the flow velocities and wall temperatures. And the turbulent dispersions are so strongly affected by the flow fields that the pollutant concentration distributions can be distinguished from the different aspect ratios, flow velocities and wall temperatures.

  4. Grain-size evolution in suspended sediment and deposits from the 2004 and 2008 controlled-flood experiments in Marble and Grand Canyons, Arizona

    Science.gov (United States)

    Draut, Amy E.; Topping, David J.; Rubin, David M.; Wright, Scott A.; Schmidt, John C.

    2010-01-01

    Since the closure of Glen Canyon Dam in 1963, the hydrology, sediment supply, and distribution and size of modern alluvial deposits in the Colorado River through Grand Canyon have changed substantially (e.g., Howard and Dolan, 1981; Johnson and Carothers, 1987; Webb et al., 1999; Rubin et al., 2002; Topping et al., 2000, 2003; Wright et al., 2005; Hazel et al., 2006). The dam has reduced the fluvial sediment supply at the upstream boundary of Grand Canyon National Park by about 95 percent. Regulation of river discharge by dam operations has important implications for the storage and redistribution of sediment in the Colorado River corridor. In the absence of natural floods, sediment is not deposited at elevations that regularly received sediment before dam closure. There has been a systemwide decrease in the size and number of subaerially exposed fluvial sand deposits since the 1960s, punctuated by episodic aggradation during the exceptional high-flow intervals in the early 1980s and by sediment input from occasional tributary floods (Beus and others, 1985; Schmidt and Graf, 1990; Kearsley et al., 1994; Schmidt et al., 2004; Wright et al., 2005; Hazel et al., 2006). Fluvial sandbars are an important component of riparian ecology that, among other functions, enclose eddy backwaters that form native-fish habitat, provide a source for eolian sand that protects some archaeological sites, and are used as campsites by thousands of river-runners annually (Rubin et al., 1990; Kearsley et al., 1994; Neal et al., 2000; Wright et al., 2005; Draut and Rubin, 2008).

  5. Spatial scale-dependent habitat heterogeneity influences submarine canyon macrofaunal abundance and diversity off the Main and Northwest Hawaiian Islands

    Science.gov (United States)

    De Leo, Fabio C.; Vetter, Eric W.; Smith, Craig R.; Rowden, Ashley A.; McGranaghan, Matthew

    2014-06-01

    The mapping of biodiversity on continental margins on landscape scales is highly relevant to marine spatial planning and conservation. Submarine canyons are widespread topographic features on continental and island margins that enhance benthic biomass across a range of oceanic provinces and productivity regimes. However, it remains unclear whether canyons enhance faunal biodiversity on landscape scales relevant to marine protected area (MPA) design. Furthermore, it is not known which physical attributes and heterogeneity metrics can provide good surrogates for large-scale mapping of canyon benthic biodiversity. To test mechanistic hypotheses evaluating the role of different canyon-landscape attributes in enhancing benthic biodiversity at different spatial scales we conducted 34 submersible dives in six submarine canyons and nearby slopes in the Hawaiian archipelago, sampling infaunal macrobenthos in a depth-stratified sampling design. We employed multivariate multiple regression models to evaluate sediment and topographic heterogeneity, canyon transverse profiles, and overall water mass variability as potential drivers of macrobenthic community structure and species richness. We find that variables related to habitat heterogeneity at medium (0.13 km2) and large (15-33 km2) spatial scales such as slope, backscatter reflectivity and canyon transverse profiles are often good predictors of macrobenthic biodiversity, explaining 16-30% of the variance. Particulate organic carbon (POC) flux and distance from shore are also important variables, implicating food supply as a major predictor of canyon biodiversity. Canyons off the high Main Hawaiian Islands (Oahu and Moloka'i) are significantly affected by organic enrichment, showing enhanced infaunal macrobenthos abundance, whereas this effect is imperceptible around the low Northwest Hawaiian Islands (Nihoa and Maro Reef). Variable canyon alpha-diversity and high rates of species turnover (beta-diversity), particularly for

  6. Safety analysis -- 200 Area Savannah River Plant, F-Canyon Operations. Supplement 4

    Energy Technology Data Exchange (ETDEWEB)

    Beary, M.M.; Collier, C.D.; Fairobent, L.A.; Graham, R.F.; Mason, C.L.; McDuffee, W.T.; Owen, T.L.; Walker, D.H.

    1986-02-01

    The F-Canyon facility is located in the 200 Separations Area and uses the Purex process to recover plutonium from reactor-irradiated uranium. The irradiated uranium is normally in the form of solid or hollow cylinders called slugs. These slugs are encased in aluminum cladding and are sent to the F-Canyon from the Savannah River Plant (SRP) reactor areas or from the Receiving Basin for Offsite Fuels (RBOF). This Safety Analysis Report (SAR) documents an analysis of the F-Canyon operations and is an update to a section of a previous SAR. The previous SAR documented an analysis of the entire 200 Separations Area operations. This SAR documents an analysis of the F-Canyon and is one of a series of documents for the Separations Area as specified in the Savannah River Implementation Plans. A substantial amount of the information supporting the conclusions of this SAR is found in the Systems Analysis. Some F-Canyon equipment has been updated during the time between the Systems Analysis and this SAR and a complete description of this equipment is included in this report. The primary purpose of the analysis was to demonstrate that the F-Canyon can be operated without undue risk to onsite or offsite populations and to the environment. In this report, risk is defined as the expected frequency of an accident, multiplied by the resulting radiological consequence in person-rem. The units of risk for radiological dose are person-rem/year. Maximum individual exposure values have also been calculated and reported.

  7. Temperature and human thermal comfort effects of street trees across three contrasting street canyon environments

    Science.gov (United States)

    Coutts, Andrew M.; White, Emma C.; Tapper, Nigel J.; Beringer, Jason; Livesley, Stephen J.

    2016-04-01

    Urban street trees provide many environmental, social, and economic benefits for our cities. This research explored the role of street trees in Melbourne, Australia, in cooling the urban microclimate and improving human thermal comfort (HTC). Three east-west (E-W) oriented streets were studied in two contrasting street canyon forms (deep and shallow) and between contrasting tree canopy covers (high and low). These streets were instrumented with multiple microclimate monitoring stations to continuously measure air temperature, humidity, solar radiation, wind speed and mean radiant temperature so as to calculate the Universal Thermal Climate Index (UTCI) from May 2011 to June 2013, focusing on summertime conditions and heat events. Street trees supported average daytime cooling during heat events in the shallow canyon by around 0.2 to 0.6 °C and up to 0.9 °C during mid-morning (9:00-10:00). Maximum daytime cooling reached 1.5 °C in the shallow canyon. The influence of street tree canopies in the deep canyon was masked by the shading effect of the tall buildings. Trees were very effective at reducing daytime UTCI in summer largely through a reduction in mean radiant temperature from shade, lowering thermal stress from very strong (UTCI > 38 °C) down to strong (UTCI > 32 °C). The influence of street trees on canyon air temperature and HTC was highly localized and variable, depending on tree cover, geometry, and prevailing meteorological conditions. The cooling benefit of street tree canopies increases as street canyon geometry shallows and broadens. This should be recognized in the strategic placement, density of planting, and species selection of street trees.

  8. A study of sound absorption by street canyon boundaries and asphalt rubber concrete pavement

    Science.gov (United States)

    Drysdale, Graeme Robert

    A sound field model, based on a classical diffusion equation, is extended to account for sound absorption in a diffusion parameter used to model sound energy in a narrow street canyon. The model accounts for a single sound absorption coefficient, separate accommodation coefficients and a combination of separate absorption and accommodation coefficients from parallel canyon walls. The new expressions are compared to the original formula through numerical simulations to reveal the effect of absorption on sound diffusion. The newly established analytical formulae demonstrate satisfactory agreement with their predecessor under perfect reflection. As well, the influence of the extended diffusion parameter on normalized sound pressure levels in a narrow street canyon is in agreement with experimental data. The diffusion parameters are used to model sound energy density in a street canyon as a function of the sound absorption coefficient of the street canyon walls. The acoustic and material properties of conventional and asphalt rubber concrete (ARC) pavement are also studied to assess how the crumb rubber content influences sound absorption in street canyons. The porosity and absolute permeability of compacted specimens of asphalt rubber concrete are measured and compared to their normal and random incidence sound absorption coefficients as a function of crumb rubber content in the modified binder. Nonlinear trends are found between the sound absorption coefficients, porosity and absolute permeability of the compacted specimens and the percentage of crumb rubber in the modified binders. The cross-sectional areas of the air voids on the surfaces of the compacted specimens are measured using digital image processing techniques and a linear relationship is obtained between the average void area and crumb rubber content. The measured material properties are used to construct an empirical formula relating the average porosity, normal incidence noise reduction coefficients and

  9. Subaqueous grain flows at the head of Carmel Submarine Canyon, California

    Science.gov (United States)

    Dingler, J.R.; Anima, R.J.

    1989-01-01

    Very coarse sand is the predominate material on the beach, adjacent shelf, and upper canyon-head slopes, while silt and clay cover the surface below a water depth at about 35 m. On angle-of-repose slopes in the upper canyon head, downslope-coarsening deposits are similar to a type of sediment gravity flow deposit formed by grain flows (sand avalanches). Using three sand fractions that were dyed different fluorescent colors, scuba divers generated sand avalanches that produced deposits similar to the natural deposits. -from Authors

  10. An analysis of background noise in selected canyons of Los Alamos County

    Energy Technology Data Exchange (ETDEWEB)

    Huchton, K.; Koch, S.W.; Robinson, R.

    1997-10-01

    The authors recorded background noise levels in six canyons within Los Alamos County in order to establish a baseline for future comparisons and to discover what noises animals are exposed to. Noise level measurements were taken within each canyon, beginning at an established starting point and at one-mile intervals up to four miles. The primary source of noise above 55 dBA was vehicular traffic. One clap of thunder provided the highest recorded noise level (76 dBA). In general, the level of noise, once away from highways and parking lots, was well below 60 dBA.

  11. Attachments for fire modeling for Building 221-T, T Plant canyon deck and railroad tunnel

    Energy Technology Data Exchange (ETDEWEB)

    Oar, D.L. [Westinghouse Hanford Co., Richland, WA (United States)

    1995-01-23

    The purpose of this attachment is to provide historical information and documentation for Document No. WHC-SD-CP-ANAL-008 Rev 0, ``Fire Modeling for Building 221-T--T Plant Canyon Deck and Railroad Tunnel``, dated September 29, 1994. This data compilation contains the following: Resumes of the Technical Director, Senior Engineer and Junior Engineer; Review and Comment Record; Software Files; CFAST Input and Output Files; Calculation Control Sheets; and Estimating Sprinkler Actuation Time in the Canyon and Railroad Tunnel. The T Plant was originally a fuel reprocessing facility. It was modified later to decontaminate and repair PuRex process equipment.

  12. Il Canyon di Caprera: un hot spot di cetacei nel Mar Tirreno centrale? = Is the Caprera Canyon an hot spot of cetaceans within the central Tyrrhenian Sea?

    OpenAIRE

    Bittau, Luca; Manconi, Renata

    2011-01-01

    Presence of cetaceans was monitored using a platform of opportunity (whale watching) off north eastern Sardinia, jrom summer 2010 to winter 2011. The monitoring consisted in seventeen surveys covering a total of 1930 km. Six cetacean species have been observed, totalizing 49 sightings. Striped dolphin was the most abundant species in the continental slope area. The waters in the Caprera Canyon appear as a potential hot spot of cetaceans and will be surveyed by dedicated campaigns. Moreover...

  13. Difference in full-filled time and its controlling factors in the Central Canyon of the Qiongdongnan Basin

    Institute of Scientific and Technical Information of China (English)

    SHANG Zhilei; XIE Xinong; LI Xushen; ZHANG Daojun; HE Yunlong; YANG Xing; CUI Mingzhe

    2015-01-01

    Based on the interpretation of high resolution 2D/3D seismic data, sedimentary filling characteristics and full-filled time of the Central Canyon in different segments in the Qiongdongnan Basin of northwestern South China Sea have been studied. The research results indicate that the initial formation age of the Central Canyon is traced back to 11.6 Ma (T40), at which the canyon began to develop due to the scouring of turbidity currents from west to east. During the period of 11.6–8.2 Ma (T40–T31), strong downcutting by gravity flow occurred, which led to the formation of the canyon. The canyon fillings began to form since 8.2 Ma (T31) and were dominated by turbidite deposits, which constituted of lateral migration and vertical superposition of turbidity channels during the time of 8.2–5.5 Ma. The interbeds of turbidity currents deposits and mass transport deposits (MTDs) were developed in the period of 5.5–3.8 Ma (T30–T28). After then, the canyon fillings were primarily made up of large scale MTDs, interrupted by small scale turbidity channels and thin pelagic mudstones. The Central Canyon can be divided into three types according to the main controlling factors, geomorphology-controlled, fault-controlled and intrusion-modified canyons. Among them, the geomorphology-controlled canyon is developed at the Ledong, Lingshui, Songnan and western Baodao Depressions, situated in a confined basin center between the northern slope and the South Uplift Belt along the Central Depression Belt. The fault-controlled canyon is developed mainly along the deep-seated faults in the Changchang Depression and eastern Baodao Depression. Intrusion-modified canyon is only occurred in the Songnan Low Uplift, which is still mainly controlled by geomorphology, the intrusion just modified seabed morphology. The full-filled time of the Central Canyon differs from west to east, displaying a tendency of being successively late eastward. The geomorphology-controlled canyon was

  14. California State Waters Map Series--Hueneme Canyon and vicinity, California

    Science.gov (United States)

    Johnson, Samuel Y.; Dartnell, Peter; Cochrane, Guy R.; Golden, Nadine E.; Phillips, Eleyne L.; Ritchie, Andrew C.; Kvitek, Rikk G.; Greene, H. Gary; Krigsman, Lisa M.; Endris, Charles A.; Clahan, Kevin B.; Sliter, Ray W.; Wong, Florence L.; Yoklavich, Mary M.; Normark, William R.

    2012-01-01

    In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California's State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration, interpretation, and visualization of swath sonar data, acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles, and bottom-sediment sampling data. The map products display seafloor morphology and character, identify potential marine benthic habitats, and illustrate both the surficial seafloor geology and shallow (to about 100 m) subsurface geology. The Hueneme Canyon and vicinity map area lies within the eastern Santa Barbara Channel region of the Southern California Bight. The area is part of the Western Transverse Ranges geologic province, which is north of the California Continental Borderland. Significant clockwise rotation - at least 90° - since the early Miocene has been proposed for the Western Transverse Ranges, and the region is presently undergoing north-south shortening. This geologically complex region forms a major biogeographic transition zone, separating the cold-temperate Oregonian province north of Point Conception from the warm-temperate California province to the south. The map area, which is offshore of the Oxnard plain and west of and along the trend of the south flank of the Santa Monica Mountains, lies at the east end of the Santa Barbara littoral cell, characterized by west-to-east littoral transport of sediment derived mainly from coastal watersheds. The Hueneme Canyon and vicinity map area in California's State Waters is characterized by two major physiographic features: (1) the nearshore continental shelf, and (2) the Hueneme and Mugu Submarine Canyon system, which, in the map area, includes Hueneme Canyon and parts

  15. Nutrient Enrichment Effects on Benthic Biodiversity by the Mississippi River and Submarine Canyon of the Northern Gulf of Mexico

    Science.gov (United States)

    Wei, C.; Rowe, G. T.

    2008-12-01

    Biodiversity is measured by (1) α diversity: number of species in relation to a standardized number of individual within a define habitat; (2) β diversity: compositional change or turnover of species between two or more spatial units; and (3) γ diversity: total number of species in a large geographic area. The pattern of biodiversity is usually driven by various physico-chemical conditions. In the deep sea, a cross-isobath parabolic diversity pattern has been well-documented for benthic macrofauna and the cause has been attributed to a dynamic equilibrium between population growth and competition exclusion along a gradient of declining food resources with depth (Rex 1981). Both nutrient-enriched (dominated by opportunistic species) and oligotrophic conditions (slow growth rate) could depress diversity, while the highest diversity can be reached by competitive equilibrium within communities at intermediate resource conditions. In the Gulf of Mexico (GoM), the discharge of Mississippi River can enhance the organic flux to the seafloor adjacent to the mouth of Mississippi River and Mississippi Canyon. The goal of this study was to test Rex's (1981) dynamic equilibrium model between depth-transects that were exposed to different levels of organic enrichment. Four treatments contrasted along the upper slope (250m to 1500m) included (1) Mississippi Canyon (active canyon), (2) De Soto Canyon (inactive canyon), (3) central slope transect (in proximity to Mississippi Canyon), and (4) the west and east slope transects (away from the influence of the Mississippi River). SeaWifs satellite data confirmed that the head of Mississippi Canyon experience highest surface primary production and export POC flux. The lowest α diversity of benthic macrofauna (collecting between 2000 and 2002) was observed at the head of the Mississippi Canyon where γ diversity was relatively high. This suggested that the canyon head was dominated by opportunistic species due the high POC flux but

  16. Final Technical Report - Modernization of the Boulder Canyon Hydroelectric Project

    Energy Technology Data Exchange (ETDEWEB)

    Taddeucci, Joe [Dept. of Public Works, Boulder, CO (United States). Utilities Division

    2013-03-29

    The Boulder Canyon Hydroelectric Project (BCH) was purchased by the City of Boulder, CO (the city) in 2001. Project facilities were originally constructed in 1910 and upgraded in the 1930s and 1940s. By 2009, the two 10 MW turbine/generators had reached or were nearing the end of their useful lives. One generator had grounded out and was beyond repair, reducing plant capacity to 10 MW. The remaining 10 MW unit was expected to fail at any time. When the BCH power plant was originally constructed, a sizeable water supply was available for the sole purpose of hydroelectric power generation. Between 1950 and 2001, that water supply had gradually been converted to municipal water supply by the city. By 2001, the water available for hydroelectric power generation at BCH could not support even one 10 MW unit. Boulder lacked the financial resources to modernize the facilities, and Boulder anticipated that when the single, operational historical unit failed, the project would cease operation. In 2009, the City of Boulder applied for and received a U.S. Department of Energy (DOE) grant for $1.18 million toward a total estimated project cost of $5.155 million to modernize BCH. The federal funding allowed Boulder to move forward with plant modifications that would ensure BCH would continue operation. Federal funding was made available through the American Recovery and Reinvestment Act (ARRA) of 2009. Boulder determined that a single 5 MW turbine/generator would be the most appropriate capacity, given the reduced water supply to the plant. Average annual BCH generation with the old 10 MW unit had been about 8,500 MW-hr, whereas annual generation with a new, efficient turbine could average 11,000 to 12,000 MW-hr. The incremental change in annual generation represents a 30% increase in generation over pre-project conditions. The old turbine/generator was a single nozzle Pelton turbine with a 5-to-1 flow turndown and a maximum turbine/generator efficiency of 82%. The new unit is a

  17. Geomorphic response of sandbars to the March 2008 high-flow experiment on the Colorado River downstream from Glen Canyon Dam

    Science.gov (United States)

    Grams, Paul E.; Hazel, Joseph E.; Schmidt, John C.; Kaplinski, Matt; Wright, Scott A.; Topping, David J.; Melis, Theodore S.

    2010-01-01

    The completion of Glen Canyon Dam in 1963 drastically altered the downstream flow regime and resulted in more than a 90 percent reduction of sand supply to the Colorado River in Grand Canyon National Park. Sandbars that were maintained by annual floods and a large sediment supply are now fewer in number and smaller in area and volume. Efforts to maintain sandbars in the current era of dam management utilize controlled floods timed to occur during brief periods of sediment enrichment that result from tributary floods. Repeat surveys of 22 sandbars made before and after controlled floods conducted in 1996, 2004, and 2008 document changes in sandbar volume; and repeat surveys at more than 100 sites document changes in sandbar elevation and morphology for the 2008 event. Each of the controlled floods resulted in sandbar deposition that was followed by erosion in the 6-month post-flood period. Erosion rates are positively correlated with post-flood dam release volumes and negatively correlated with post-flood tributary sediment supply volume. October 2008 sandbar volume was similar or larger than sandbar volume in February 1996, before the first of the three controlled floods. Deposition during the 2008 controlled flood was also associated with increases in the quantity of backwater habitat, which is used by native and non-native fish.

  18. Correcting acoustic Doppler current profiler discharge measurement bias from moving-bed conditions without global positioning during the 2004 Glen Canyon Dam controlled flood on the Colorado River

    Science.gov (United States)

    Gartner, J.W.; Ganju, N.K.

    2007-01-01

    Discharge measurements were made by acoustic Doppler current profiler at two locations on the Colorado River during the 2004 controlled flood from Glen Canyon Dam, Arizona. Measurement hardware and software have constantly improved from the 1980s such that discharge measurements by acoustic profiling instruments are now routinely made over a wide range of hydrologic conditions. However, measurements made with instruments deployed from moving boats require reliable boat velocity data for accurate measurements of discharge. This is normally accomplished by using special acoustic bottom track pings that sense instrument motion over bottom. While this method is suitable for most conditions, high current flows that produce downstream bed sediment movement create a condition known as moving bed that will bias velocities and discharge to lower than actual values. When this situation exists, one solution is to determine boat velocity with satellite positioning information. Another solution is to use a lower frequency instrument. Discharge measurements made during the 2004 Glen Canyon controlled flood were subject to moving-bed conditions and frequent loss of bottom track. Due to site conditions and equipment availability, the measurements were conducted without benefit of external positioning information or lower frequency instruments. This paper documents and evaluates several techniques used to correct the resulting underestimated discharge measurements. One technique produces discharge values in good agreement with estimates from numerical model and measured hydrographs during the flood. ?? 2007, by the American Society of Limnology and Oceanography, Inc.

  19. Erosion during extreme flood events dominates Holocene canyon evolution in northeast Iceland.

    Science.gov (United States)

    Baynes, Edwin R C; Attal, Mikaël; Niedermann, Samuel; Kirstein, Linda A; Dugmore, Andrew J; Naylor, Mark

    2015-02-24

    Extreme flood events have the potential to cause catastrophic landscape change in short periods of time (10(0) to 10(3) h). However, their impacts are rarely considered in studies of long-term landscape evolution (>10(3) y), because the mechanisms of erosion during such floods are poorly constrained. Here we use topographic analysis and cosmogenic (3)He surface exposure dating of fluvially sculpted surfaces to determine the impact of extreme flood events within the Jökulsárgljúfur canyon (northeast Iceland) and to constrain the mechanisms of bedrock erosion during these events. Surface exposure ages allow identification of three periods of intense canyon cutting about 9 ka ago, 5 ka ago, and 2 ka ago during which multiple large knickpoints retreated large distances (>2 km). During these events, a threshold flow depth was exceeded, leading to the toppling and transportation of basalt lava columns. Despite continuing and comparatively large-scale (500 m(3)/s) discharge of sediment-rich glacial meltwater, there is no evidence for a transition to an abrasion-dominated erosion regime since the last erosive event because the vertical knickpoints have not diffused over time. We provide a model for the evolution of the Jökulsárgljúfur canyon through the reconstruction of the river profile and canyon morphology at different stages over the last 9 ka and highlight the dominant role played by extreme flood events in the shaping of this landscape during the Holocene.

  20. FRESHWATER ALGAE OF RAE LAKES BASIN, KINGS CANYON NATIONAL PARK (CALIFORNIA)

    Science.gov (United States)

    This report illustrates and characterizes algae (exclusive of diatoms) found in Kings Canyon National Park, California and describes their distribution among the Rae Lakes within. It is the first taxonomic study of the freshwater algae for the southern Sierra Nevada and the most ...

  1. Flushing of a dense fluid from an urban canyon part 1: Steady state measurements

    Science.gov (United States)

    Kaye, Nigel; Baratian, Zahra

    2011-11-01

    We consider the role of buoyancy on the vertical transport of a dense gas due to a horizontal wind flow above a street canyon. The density of the pollutant suppresses vertical mixing as the turbulent shear flow at the top of the canyon must do work to raise the dense gas up above the canyon top. We present results of a series of experiments to measure the rate of removal of a dense miscible fluid from a two dimensional square canyon open at the top. The cavity is formed by square blocks up- and down-stream. Dense fluid is introduced at a constant rate at the base of the cavity and is removed by mixing with the flow passing over the top of the cavity. Two different steady flows are observed. For higher Richardson numbers, a two layer stratification develops in which there is a relatively sharp interface. In this case the mixing is parameterized in terms of an entrainment velocity across the interface that is a function of the Richardson number and the fractional depth of the interface below the cavity top. For lower Richardson numbers no interface is observed and the buoyancy increases linearly with height above the cavity base. We also found a range of Richardson numbers for which both steady stratifications are possible and for which the steady flow depends on the initial conditions.

  2. English Writing Placement Recommendations at College of the Canyons: An Analysis of Disproportionate Impact.

    Science.gov (United States)

    Gerda, Joseph

    A study was undertaken at California's College of the Canyons (CoC) to determine whether evidence existed of disproportionate impact in English course placement based on student ethnicity, gender, or age. Data were compiled for all 4,309 students tested between spring 1993 and fall 1995, while the standard for disproportionate impact was taken…

  3. English Reading Placement Recommendations at College of the Canyons: An Analysis of Disproportionate Impact.

    Science.gov (United States)

    Gerda, Joseph

    A study was undertaken at California's College of the Canyons (CC) to determine whether evidence existed of disproportionate impact in English reading course placement based on student ethnicity, gender, or age. Data were compiled for all 4,312 students tested between spring 1993 and fall 1995, while the standard for disproportionate impact was…

  4. Seasonal dependence of the urban heat island on the street canyon aspect ratio

    NARCIS (Netherlands)

    Theeuwes, N.E.; Steeneveld, G.J.; Ronda, R.J.; Heusinkveld, B.G.; Hove, van L.W.A.; Holtslag, A.A.M.

    2014-01-01

    In this paper we study the relation between the urban heat island (UHI) in the urban canyon and street geometry, in particular the aspect ratio. Model results and observations show that two counteracting processes govern the relation between the nocturnal UHI and the building aspect ratio: i.e. trap

  5. Ground motions around a semicircular canyon with a dipping edge under SH plane wave incidence

    Science.gov (United States)

    Chang, Kao-Hao; Tsaur, Deng-How; Wang, Jeen-Hwa

    2016-01-01

    In order to explore the spatial distribution and temporal variation of ground motions near a semicircular canyon with a dipping edge, a simplified mathematical model is constructed. Based on the region-matching technique, a Fourier-Bessel series solution for the plane SH-wave excitation is derived and then applied to theoretically simulate the seismic response of the canyon. The use of the adequate wavefunctions and a newly derived Graf's addition formula can solve the unknown expansion coefficients. Parametric analyses with respect to the frequency of input motion, angle of incidence, and canyon geometry are illustrated. Both frequency- and time-domain computations are presented. The canonical case, a completed semicircular canyon, which has the exact analytical solution, and the horizontally truncated case analyzed in previous works are considered as particular cases of the proposed general model. Comparisons with boundary-element solutions show good agreement. Steady-state results show that the phenomenon of wave focusing tends to be significant when the incident angle bends toward the horizontal ground surface. Propagation and attenuation of scattered waves that originated from the surficial anomaly are exhibited in transient-state simulations.

  6. 76 FR 29280 - Diablo Canyon Independent Spent Fuel Storage Installation; Notice of Docketing for Amendment...

    Science.gov (United States)

    2011-05-20

    ... COMMISSION Diablo Canyon Independent Spent Fuel Storage Installation; Notice of Docketing for Amendment...: John M. Goshen, Project Manager, Licensing Branch, Division of Spent Fuel Storage and Transportation..., possession, storage and transfer of spent fuel, reactor-related Greater than Class C waste and...

  7. Numerical modeling of flow and pollutant dispersion in street canyons with tree planting

    Energy Technology Data Exchange (ETDEWEB)

    Balczo, Marton [Budapest Univ. of Technology and Economics (Hungary). Theodore von Karman Wind Tunnel Lab.; Gromke, Christof; Ruck, Bodo [Karlsruhe Univ. (Germany). Lab. of Building- and Environmental Aerodynamics

    2009-04-15

    Numerical simulations of the impact of tree planting on airflow and traffic pollutant dispersion in urban street canyons have been performed using the commercial CFD (Computational Fluid Dynamics) code MISKAM. A {kappa}-{epsilon} turbulence model including additional terms for the treatment of vegetation, has been employed to close the Reynolds-averaged-Navier-Stokes (RANS) equations. The numerical results were compared to wind tunnel data. In the case of the investigated wind direction perpendicular to the street axis, the presence of trees lead to increased pollutant concentrations inside the canyon. Concentrations increased strongly on the upstream side of the canyon, while on the downstream side a small concentration decrease could be observed. Lower flow velocities and higher pollutant concentrations were found in the numerical simulations when directly compared to the experimental results. However, the impact of tree planting on airflow and concentration fields when compared to the treeless street canyon as a reference configuration were simulated quite well, meaning that relative changes were similar in the wind tunnel investigations and numerical computations. This feature qualifies MISKAM for use as a tool for assessing the impacts of vegetation on local air quality. (orig.)

  8. 75 FR 41232 - Deer Flat National Wildlife Refuge, Canyon, Owyhee, Payette, and Washington Counties, ID; Malheur...

    Science.gov (United States)

    2010-07-15

    ... Fish and Wildlife Service Deer Flat National Wildlife Refuge, Canyon, Owyhee, Payette, and Washington...), intend to prepare a comprehensive conservation plan (CCP) for Deer Flat National Wildlife Refuge (Refuge....gov . Fax: Attn: Refuge Manager, (208) 467-1019. U.S. Mail: Refuge Manager, Deer Flat...

  9. 78 FR 16523 - Deer Flat National Wildlife Refuge, Canyon, Payette, Owyhee, and Washington Counties, ID, and...

    Science.gov (United States)

    2013-03-15

    ... Fish and Wildlife Service Deer Flat National Wildlife Refuge, Canyon, Payette, Owyhee, and Washington... comprehensive conservation plan and environmental impact statement (Draft CCP/EIS) for the Deer Flat National... may request hard copies or a CD-ROM of the documents. Email: deerflat@fws.gov . Include ``Deer...

  10. Influence of photochemical processes on traffic-related airborne pollutants in urban street canyon

    Science.gov (United States)

    Střižík, Michal; Zelinger, Zdeněk; Kubát, Pavel; Civiš, Svatopluk; Bestová, Iva; Nevrlý, Václav; Kadeřábek, Petr; Čadil, Jan; Berger, Pavel; Černý, Alexandr; Engst, Pavel

    2016-09-01

    The urban street canyon of Legerova Street is part of the north-south trunk road that passes through the centre of Prague and remains an unresolved environmental issue for the capital of the Czech Republic. As many as one hundred thousand cars move through this region per day, and mortality has increased as a result of dust, NOx and other exhaust pollutants. The spatial distribution of pollutants (i.e., NO2, NO, and O3) during a day was measured by combined DIAL/SODAR techniques and spot analyzers that were appropriately located near the bottom of the street canyon. The measurements were performed under different meteorological conditions (autumn versus summer period). A purely physical approach does not provide a true description of reality due to photochemical processes that take place in the street canyon atmosphere. Sunlight in the summer triggers the production of ozone and thereby influences the concentration of NO2. The formation of an inverse non-diffuse vertical concentration distribution of NO2 in the morning hours was found to be related to the direct emission of O3 in the street and its background concentration. Rapid changes of NO2 concentrations were observed over time and in the vertical profile. An approach using a photochemical reactor to describe processes in a street canyon atmosphere was developed and verified as a useful tool for prediction purposes.

  11. The urban canyon and building energy use: Urban density versus daylight and passive solar gains

    DEFF Research Database (Denmark)

    Strømann-Andersen, Jakob Bjørn; Sattrup, Peter Andreas

    2011-01-01

    The link between urban density and building energy use is a complex balance between climatic factors and the spatial, material and use patterns of urban spaces and the buildings that constitute them. This study uses the concept of the urban canyon to investigate the ways that the energy performan...

  12. 78 FR 3370 - Proposed Establishment of the Ballard Canyon Viticultural Area

    Science.gov (United States)

    2013-01-16

    ... the name ``Ballard Canyon'' in a brand name, including a trademark, or in another label reference as..., and pulp of the grape which contribute to the color, flavor, and aroma of the wine. Temperature The... producing thicker skins, lower juice-to-skin ratios during ferment, and wines of deeper color and...

  13. Assessment of tight-gas resources in Canyon sandstones of the Val Verde Basin, Texas, 2016

    Science.gov (United States)

    Schenk, Christopher J.; Tennyson, Marilyn E.; Klett, Timothy R.; Mercier, Tracey J.; Brownfield, Michael E.; Gaswirth, Stephanie B.; Hawkins, Sarah J.; Leathers-Miller, Heidi M.; Marra, Kristen R.; Finn, Thomas M.; Pitman, Janet K.

    2016-07-08

    Using a geology-based assessment methodology, the U.S. Geological Survey assessed mean resources of 5 trillion cubic feet of gas and 187 million barrels of natural gas liquids in tight-gas assessment units in the Canyon sandstones of the Val Verde Basin, Texas.

  14. A refined astronomically calibrated 40Ar/39Ar age for Fish Canyon sanidine

    NARCIS (Netherlands)

    Rivera, T.A.; Storey, M.; Zeeden, C.; Hilgen, F.J.; Kuiper, K.

    2011-01-01

    Intercalibration between the astronomical and radio-isotopic dating methods provides a means to improving accuracy and reducing uncertainty of an integrated, multi-chronometer geologic timescale. Here we report a high-precision 40Ar/39Ar age for the FishCanyon sanidine (FCs) neutron fluence monitor,

  15. Seasonal pathways of organic matter within the Avilés submarine canyon: Food web implications

    Science.gov (United States)

    Romero-Romero, Sonia; Molina-Ramírez, Axayacatl; Höfer, Juan; Duineveld, Gerard; Rumín-Caparrós, Aitor; Sanchez-Vidal, Anna; Canals, Miquel; Acuña, José Luis

    2016-11-01

    The transport and fate of organic matter (OM) sources within the Avilés submarine canyon (Cantabrian Sea, Southern Bay of Biscay) were studied using carbon and nitrogen stable isotope ratios. The isotopic composition of settling particles and deep bottom sediments closely resembled that of surface particulate OM, and there were no marked differences in the isotopic composition of settling particles inside and outside of the AC. This indicates that the Avilés Canyon (AC) receives inputs of sinking OM mostly from the upper water column and less through advective near-bottom down-canyon transport. Sinking OM fluxes are of marine and terrestrial origin in proportions which vary seasonally. Analysis of δ13C in the canyon fauna indicates a dependence on OM mainly produced by marine phytoplankton. A tight coupling of isotopic signatures between pelagic organisms and benthic suspension feeders reflects an active biological vertical transport of OM from the surface to the deep-sea. The food web presented seasonal variations in the trophic niche width and the amplitude of the primary carbon sources, reflecting seasonality in the availability of fresh particulate OM. Those seasonal changes are larger for benthic organisms of lower trophic levels.

  16. Final environmental statement related to the Plateau Resources Limited Shootering Canyon Uranium Project (Garfield County, Utah)

    International Nuclear Information System (INIS)

    The proposed action is the issuance of a Source Material License to Plateau Resources, Ltd., for the construction and operation of the proposed Shootering Canyon Uranium Project with a product (U3O8) production limited to 2.2 x 105 kg (4.9 x 105 lb) per year. Impacts to the area from the operation of the Shootering Canyon Uranium Project will include the following: alterations of up to 140 ha (350 acres) that will be occupied by the mill, mill facilities, borrow areas, tailings areas, and roads; an increase in the existing background radiation levels of the mill area as a result of continuous but small releases of uranium, radium, radon, and other, radioactive materials during construction and operation; socioeconomic effects on the local area, particularly the proposed community of Ticaboo, where the majority of workers will be housed during project construction and operation; and production of solid waste material (tailings) from the mill at a rate of about 680 MT (750 tons) per day and deposition as a slurry in an onsite impoundment area; construction and operation of the Shootering Canyon mill will provide employment and induced economic benefits for the region but may also result in some socioeconomic stress. On the basis of the analysis and evaluation set forth in this Environmental Statement, it is proposed that any license issued for the Shootering Canyon mill should be subject to certain conditions for the protection of the environment. A list is included. Nine appendices are also included

  17. The timing of sediment transport down Monterey Submarine Canyon, offshore California

    DEFF Research Database (Denmark)

    Stevens, Thomas; Paull, C.K.; Ussler, W., III;

    2014-01-01

    to demonstrate relatively rapid, decadal-scale sand transport to at least 1.1 km depth and more variable decadal- to millennial-scale transport to a least 3.5 km depth on the fan. Significant differences between the time sand was last exposed at the canyon head (OSL age) and the timing of deposition of the sand...

  18. Remote sensing approach to map riparian vegetation of the Colorado River Ecosystem, Grand Canyon area, Arizona

    Science.gov (United States)

    Nguyen, U.; Glenn, E.; Nagler, P. L.; Sankey, J. B.

    2015-12-01

    Riparian zones in the southwestern U.S. are usually a mosaic of vegetation types at varying states of succession in response to past floods or droughts. Human impacts also affect riparian vegetation patterns. Human- induced changes include introduction of exotic species, diversion of water for human use, channelization of the river to protect property, and other land use changes that can lead to deterioration of the riparian ecosystem. This study explored the use of remote sensing to map an iconic stretch of the Colorado River in the Grand Canyon National Park, Arizona. The pre-dam riparian zone in the Grand Canyon was affected by annual floods from spring run-off from the watersheds of Green River, the Colorado River and the San Juan River. A pixel-based vegetation map of the riparian zone in the Grand Canyon, Arizona, was produced from high-resolution aerial imagery. The map was calibrated and validated with ground survey data. A seven-step image processing and classification procedure was developed based on a suite of vegetation indices and classification subroutines available in ENVI Image Processing and Analysis software. The result was a quantitative species level vegetation map that could be more accurate than the qualitative, polygon-based maps presently used on the Lower Colorado River. The dominant woody species in the Grand Canyon are now saltcedar, arrowweed and mesquite, reflecting stress-tolerant forms adapted to alternated flow regimes associated with the river regulation.

  19. Disturbance, productivity and diversity in deep-sea canyons: A worm's eye view

    NARCIS (Netherlands)

    Paterson, G.L.J.; Glover, A.G.; Cunha, M.R.; Neal, L.; de Stigter, H.C.; Kiriakoulakis, K.; Billett, D.S.M.; Wolff, G.A.; Tiago, A.; Ravara, A.; Lamont, P.; Tyler, P.

    2011-01-01

    The abundance, diversity and assemblage structure of polychaetes from the Nazare, Setubal and Cascais Canyons along the Iberian Margin were studied as part of the EU project HERMES. A Dynamic Equilibrium Model (DEM) was used to identify the main environmental factors structuring the assemblages. Box

  20. Influence of roadside hedgerows on air quality in urban street canyons

    Science.gov (United States)

    Gromke, Christof; Jamarkattel, Nabaraj; Ruck, Bodo

    2016-08-01

    Understanding pollutant dispersion in the urban environment is an important aspect of providing solutions to reduce personal exposure to vehicle emissions. To this end, the dispersion of gaseous traffic pollutants in urban street canyons with roadside hedges was investigated. The study was performed in an atmospheric boundary layer wind tunnel using a reduced-scale (M = 1:150) canyon model with a street-width-to-building-height ratio of W/H = 2 and a street-length-to-building-height ratio of L/H = 10. Various hedge configurations of differing height, permeability and longitudinal segmentation (continuous over street length L or discontinuous with clearings) were investigated. Two arrangements were examined: (i) two eccentric hedgerows sidewise of the main traffic lanes and (ii) one central hedgerow between the main traffic lanes. In addition, selected configurations of low boundary walls, i.e. solid barriers, were examined. For a perpendicular approach wind and in the presence of continuous hedgerows, improvements in air quality in the center area of the street canyon were found in comparison to the hedge-free reference scenario. The pollutant reductions were greater for the central hedge arrangements than for the sidewise arrangements. Area-averaged reductions between 46 and 61% were observed at pedestrian head height level on the leeward side in front of the building for the centrally arranged hedges and between 18 and 39% for the two hedges arranged sidewise. Corresponding area-averaged reductions ranging from 39 to 55% and from 1 to 20% were found at the bottom of the building facades on the leeward side. Improvements were also found in the areas at the lateral canyon ends next to the crossings for the central hedge arrangements. For the sidewise arrangements, increases in traffic pollutants were generally observed. However, since the concentrations in the end areas were considerably lower compared to those in the center area, an overall improvement remained

  1. Structure-forming corals and sponges and their use as fish habitat in Bering Sea submarine canyons.

    Directory of Open Access Journals (Sweden)

    Robert J Miller

    Full Text Available Continental margins are dynamic, heterogeneous settings that can include canyons, seamounts, and banks. Two of the largest canyons in the world, Zhemchug and Pribilof, cut into the edge of the continental shelf in the southeastern Bering Sea. Here currents and upwelling interact to produce a highly productive area, termed the Green Belt, that supports an abundance of fishes and squids as well as birds and marine mammals. We show that in some areas the floor of these canyons harbors high densities of gorgonian and pennatulacean corals and sponges, likely due to enhanced surface productivity, benthic currents and seafloor topography. Rockfishes, including the commercially important Pacific ocean perch, Sebastes alutus, were associated with corals and sponges as well as with isolated boulders. Sculpins, poachers and pleuronectid flounders were also associated with corals in Pribilof Canyon, where corals were most abundant. Fishes likely use corals and sponges as sources of vertical relief, which may harbor prey as well as provide shelter from predators. Boulders may be equivalent habitat in this regard, but are sparse in the canyons, strongly suggesting that biogenic structure is important fish habitat. Evidence of disturbance to the benthos from fishing activities was observed in these remote canyons. Bottom trawling and other benthic fishing gear has been shown to damage corals and sponges that may be very slow to recover from such disturbance. Regulation of these destructive practices is key to conservation of benthic habitats in these canyons and the ecosystem services they provide.

  2. Structure-forming corals and sponges and their use as fish habitat in Bering Sea submarine canyons.

    Science.gov (United States)

    Miller, Robert J; Hocevar, John; Stone, Robert P; Fedorov, Dmitry V

    2012-01-01

    Continental margins are dynamic, heterogeneous settings that can include canyons, seamounts, and banks. Two of the largest canyons in the world, Zhemchug and Pribilof, cut into the edge of the continental shelf in the southeastern Bering Sea. Here currents and upwelling interact to produce a highly productive area, termed the Green Belt, that supports an abundance of fishes and squids as well as birds and marine mammals. We show that in some areas the floor of these canyons harbors high densities of gorgonian and pennatulacean corals and sponges, likely due to enhanced surface productivity, benthic currents and seafloor topography. Rockfishes, including the commercially important Pacific ocean perch, Sebastes alutus, were associated with corals and sponges as well as with isolated boulders. Sculpins, poachers and pleuronectid flounders were also associated with corals in Pribilof Canyon, where corals were most abundant. Fishes likely use corals and sponges as sources of vertical relief, which may harbor prey as well as provide shelter from predators. Boulders may be equivalent habitat in this regard, but are sparse in the canyons, strongly suggesting that biogenic structure is important fish habitat. Evidence of disturbance to the benthos from fishing activities was observed in these remote canyons. Bottom trawling and other benthic fishing gear has been shown to damage corals and sponges that may be very slow to recover from such disturbance. Regulation of these destructive practices is key to conservation of benthic habitats in these canyons and the ecosystem services they provide. PMID:22470486

  3. Submarine canyons on the north of Chiwei Island:influenced by recent extension of the southern Okinawa Trough

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yuexia; LIU Baohua; LI Xishuang; LIU Chenguang; WU Jinlong; WANG Kuiyang

    2008-01-01

    Based on new multibeam bathymetric data and about 300 km long single seismic profiles,three topographic units were identified:the canyons,fractural valley and submarine terrace on the north of Chiwei Island where is a structural transition zone between the southern trough and the middle trough.The Chiwei Canyon and the North Chiwei Canyon are two of the largest canyons in the East China Sea (ECS) slope.Topographic features and architectures of them are described.The study shows that both of them are originated along faults.The evolution and spatial distribution of topographic units in the study area are controlled mainly by three groups of faults which were formed and reactive in the recent extensional phase of Okinawa Trough.The Chiwei Canyon was initia-ted during the middle Pleistocene and guided by F4 that is a N-S trending fault on the slope and F1,a large NW-SE trending fault on the trough.The pathway migration from the remnant channel to the present one of Chiwei Canyon is the result of uplift of tilted fault block that is coupled to the recent extension movements of the southern trough.The submarine terrace is detached from the ECS slope by the NEE-trending fault.The North Chiwei Canyon,developing during the late Pleistocene,is guided by F5,a N-S trending fault,diverted and blocked by the submarine terrace.

  4. Preliminary geologic map of Black Canyon and surrounding region, Nevada and Arizona

    Science.gov (United States)

    Felger, Tracey J.; Beard, L. Sue; Anderson, Zachary W.; Fleck, Robert J.; Wooden, Joseph L.; Seixas, Gustav B.

    2014-01-01

    Thermal springs in Black Canyon of the Colorado River, downstream of Hoover Dam, are important recreational, ecological, and scenic features of the Lake Mead National Recreation Area. This report presents the results from a U.S. Geological Survey study of the geologic framework of the springs. The study was conducted in cooperation with the National Park Service and funded by both the National Park Service and National Cooperative Geologic Mapping Program of the U.S. Geological Survey. The report has two parts: A, a 1:48,000-scale geologic map created from existing geologic maps and augmented by new geologic mapping and geochronology; and B, an interpretive report that presents results based on a collection of fault kinematic data near springs within Black Canyon and construction of 1:100,000-scale geologic cross sections that extend across the western Lake Mead region. Exposures in Black Canyon are mostly of Miocene volcanic rocks, underlain by crystalline basement composed of Miocene plutonic rocks or Proterozoic metamorphic rocks. The rocks are variably tilted and highly faulted. Faults strike northwest to northeast and include normal and strike-slip faults. Spring discharge occurs along faults intruded by dacite dikes and plugs; weeping walls and seeps extend away from the faults in highly fractured rock or relatively porous volcanic breccias, or both. Results of kinematic analysis of fault data collected along tributaries to the Colorado River indicate two episodes of deformation, consistent with earlier studies. The earlier episode formed during east-northeast-directed extension, and the later during east-southeast-directed extension. At the northern end of the study area, pre-existing fault blocks that formed during the first episode were rotated counterclockwise along the left-lateral Lake Mead Fault System. The resulting fault pattern forms a complex arrangement that provides both barriers and pathways for groundwater movement within and around Black

  5. The surface sediment distribution and sedimentary environment of the Pearl River Submarine Canyon

    Science.gov (United States)

    Han, X.; Chu, F.; Li, J.; Xu, D.; Zhang, W.

    2012-12-01

    The grain size composition, particle size parameters, clay mineral, and detrital mineral of surface sediment of this The Pearl River Submarine Canyon (the PRSC, for short) area have been measured and analyzed, which were took sampling in 2005 and 2006 in the northern South China Sea. The results show that the isolines distribution features of these parameters have very good corresponding relation with the geomorphology of the PRSC. On the continental-shelf slope break of the PRSC head (123m-1500m water depth), the close interval isolines of the surface sediment particle size percentage content and size parameters nearly parallel with the water depth isolines. The data of sand percentage content and mean grain size, sorting coefficient and skewness decreases with the increase of water depth. The other way around, the silt and clay percentage content and kurtosis value increase with deeper water. These show that in the canyon head sediment distribution was controlled by the material source (mainly comes from the Pearl River), slope and the northern South China Sea offshore current. In the main PRSC area, the surface sediment grain size composition content and grain size parameter numerical isolines have become a isoline platform which has the similar shape with the main PRSC and extended to the northeast and southwest deep sea basin. This means that the sedimentary environment of main canyon is apparently different with the head environment, that is affected by the high-temperature and high-salt the South China Sea Branch of by the Kuroshio along the 3500 m water depth isoline and alone the canyon to bending. The 25% percentage content isoline of the calcium biological and 45% percentage content isoline of the light mineral show a broadband distribution along the head and upside of the PRSC, and reduces in the entrance with the water depth isolines, apparently influenced by the South China Sea Branch of the Kuroshio. A high value area of the silt, clay mineral, light

  6. Fluid mechanical dispersion of airborne pollutants inside urban street canyons subjecting to multi-component ventilation and unstable thermal stratifications.

    Science.gov (United States)

    Mei, Shuo-Jun; Liu, Cheng-Wei; Liu, Di; Zhao, Fu-Yun; Wang, Han-Qing; Li, Xiao-Hong

    2016-09-15

    The pedestrian level pollutant transport in street canyons with multiple aspect ratios (H/W) is numerically investigated in the present work, regarding of various unstable thermal stratification scenarios and plain surrounding. Non-isothermal turbulent wind flow, temperature field and pollutant spread within and above the street canyons are solved by the realizable k-ε turbulence model along with the enhanced wall treatment. One-vortex flow regime is observed for shallow canyons with H/W=0.5, whereas multi-vortex flow regime is observed for deep canyons with H/W=2.0. Both one-vortex and multi-vortex regimes could be observed for the street canyons with H/W=1.0, where the secondary vortex could be initiated by the flow separation and intensified by unstable thermal stratification. Air exchange rate (AER) and pollutant retention time are adopted to respectively evaluate the street canyon ventilation and pollutant removal performance. A second-order polynomial functional relationship is established between AER and Richardson number (Ri). Similar functional relationship could be established between retention time and Ri, and it is only valid for canyons with one-vortex flow regime. In addition, retention time could be prolonged abruptly for canyons with multi-vortex flow regime. Very weak secondary vortex is presented at the ground level of deep canyons with mild stratification, where pollutants are highly accumulated. However, with the decrease of Ri, pollutant concentration adjacent to the ground reduces accordingly. Present research could be applied to guide the urban design and city planning for enhancing pedestrian environment. PMID:27262984

  7. Wildlife Protection, Mitigation, and Enhancement Plans, Anderson Ranch and Black Canyon Facilities: Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Meuleman, G. Allyn

    1987-06-01

    Under direction of the Pacific Northwest Electric Power Planning and Conservation Act of 1980, and the subsequent Northwest Power Planning Council's Columbia River Basin Fish and Wildlife Program, projects have been developed in Idaho to mitigate the impacts to wildlife habitat and production due to the development and operation of the Anderson Ranch and Black Canyon Facilities (i.e., dam, power plant, and reservoir areas). The Anderson Ranch Facility covered about 4812 acres of wildlife habitat while the Black Canyon Facility covered about 1115 acres. These acreages include dam and power plant staging areas. A separate mitigation plan has been developed for each facility. A modified Habitat Evaluation Procedure (HEP) was used to assess the benefits of the mitigation plans to wildlife. The interagency work group used the target species Habitat Units (HU's) lost at each facility as a guideline during the mitigation planning process, while considering the needs of wildlife in the areas. Totals of 9619 and 2238 target species HU's were estimated to be lost in the Anderson Ranch and Black Canyon Facility areas, respectively. Through a series of projects, the mitigation plans will provide benefits of 9620 target species HU's to replace Anderson Ranch wildlife impacts and benefits of 2195 target species HU's to replace Black Canyon wildlife impacts. Target species to be benefited by the Anderson Ranch and/or Black Canyon mitigation plans include the mallard, Canada goose, mink, yellow warbler, black-capped chickadee, ruffed grouse, mule deer, blue grouse, sharp-tailed grouse, ring-necked pheasant, and peregrine falcon.

  8. Growth and asymmetry of soil microfungal colonies from "Evolution Canyon," Lower Nahal Oren, Mount Carmel, Israel.

    Directory of Open Access Journals (Sweden)

    Shmuel Raz

    Full Text Available BACKGROUND: Fluctuating asymmetry is a contentious indicator of stress in populations of animals and plants. Nevertheless, it is a measure of developmental noise, typically obtained by measuring asymmetry across an individual organism's left-right axis of symmetry. These individual, signed asymmetries are symmetrically distributed around a mean of zero. Fluctuating asymmetry, however, has rarely been studied in microorganisms, and never in fungi. OBJECTIVE AND METHODS: We examined colony growth and random phenotypic variation of five soil microfungal species isolated from the opposing slopes of "Evolution Canyon," Mount Carmel, Israel. This canyon provides an opportunity to study diverse taxa inhabiting a single microsite, under different kinds and intensities of abiotic and biotic stress. The south-facing "African" slope of "Evolution Canyon" is xeric, warm, and tropical. It is only 200 m, on average, from the north-facing "European" slope, which is mesic, cool, and temperate. Five fungal species inhabiting both the south-facing "African" slope, and the north-facing "European" slope of the canyon were grown under controlled laboratory conditions, where we measured the fluctuating radial asymmetry and sizes of their colonies. RESULTS: Different species displayed different amounts of radial asymmetry (and colony size. Moreover, there were highly significant slope by species interactions for size, and marginally significant ones for fluctuating asymmetry. There were no universal differences (i.e., across all species in radial asymmetry and colony size between strains from "African" and "European" slopes, but colonies of Clonostachys rosea from the "African" slope were more asymmetric than those from the "European" slope. CONCLUSIONS AND SIGNIFICANCE: Our study suggests that fluctuating radial asymmetry has potential as an indicator of random phenotypic variation and stress in soil microfungi. Interaction of slope and species for both growth rate

  9. Local Mass Transfer Coefficient for Idealized 2D Urban Street Canyon Models

    Science.gov (United States)

    Leung, Ka Kit; Liu, Chun-Ho

    2011-09-01

    Human activities in urban areas is one of the major sources of anthropogenic releases in the atmospheric boundary layer (ABL). The mechanism of urban morphology for the heat and mass transfer in built environment is thus an attractive topic in the research community. In this paper, a series of laboratory measurements is conducted to elucidate the mass transfer from hypothetical urban roughness constructed by idealized 2D street canyons. The experiments are carried out in the wind tunnel in the University of Hong Kong. The urban ABL structure inside the wind tunnel is controlled by placing small cubic Styrofoam blocks upstream of the test section. The street canyons are fabricated by movable rectangular acrylic blocks so that different building height to street width (aspect) ratios are examined. The height of building blocks is kept minimum to make sure that the urban ABL over the street canyons is high enough for fully developed turbulent flows. The prevailing wind is normal to the street axis, demonstrating the scenario of least pollutant removal from the street canyons to the urban ABL. The sample street canyon is covered by soaked filter papers to represent uniform mass concentrations on the building facades and ground surface. The wet bulb temperature of the filter papers is continuously monitored to ensure saturated conditions. Their weight before and after an experiment is used to measure the amount of water evaporated. Preliminary results illustrate the local mass transfer coefficient distribution for aspect ratios 1/4, 1/2, 1, and 2, which are comparable with those available in literuatre.

  10. The Glen Canyon Dam adaptive management program: progress and immediate challenges

    Science.gov (United States)

    Hamill, John F.; Melis, Theodore S.

    2012-01-01

    Adaptive management emerged as an important resource management strategy for major river systems in the United States (US) in the early 1990s. The Glen Canyon Dam Adaptive Management Program (‘the Program’) was formally established in 1997 to fulfill a statutory requirement in the 1992 Grand Canyon Protection Act (GCPA). The GCPA aimed to improve natural resource conditions in the Colorado River corridor in the Glen Canyon National Recreation Area and Grand Canyon National Park, Arizona that were affected by the Glen Canyon dam. The Program achieves this by using science and a variety of stakeholder perspectives to inform decisions about dam operations. Since the Program started the ecosystem is now much better understood and several biological and physical improvements have been achieved. These improvements include: (i) an estimated 50% increase in the adult population of endangered humpback chub (Gila cypha) between 2001 and 2008, following previous decline; (ii) a 90% decrease in non-native rainbow trout (Oncorhynchus mykiss), which are known to compete with and prey on native fish, as a result of removal experiments; and (iii) the widespread reappearance of sandbars in response to an experimental high-flow release of dam water in March 2008.Although substantial progress has been made, the Program faces several immediate challenges. These include: (i) defining specific, measurable objectives and desired future conditions for important natural, cultural and recreational attributes to inform science and management decisions; (ii) implementing structural and operational changes to improve collaboration among stakeholders; (iii) establishing a long-term experimental programme and management plan; and (iv) securing long-term funding for monitoring programmes to assess ecosystem and other responses to management actions. Addressing these challenges and building on recent progress will require strong and consistent leadership from the US Department of the Interior

  11. Analysis of F-Canyon Effluents During the Dissolution Cycle with a Fourier Transform Infrared Spectrometer/Multipath Cell

    International Nuclear Information System (INIS)

    Air samples from F-Canyon effluents were collected at the F-Canyon stack and transported to a laboratory at the Savannah River Technology Center (SRTC) for analysis using a Fourier transform infrared spectrometer in conjunction with a multipath cell. Air samples were collected during the decladding and acid cuts of the dissolution of the irradiated aluminum-cladded slugs. The FTIR analyses of the air samples show the presence of NO2, NO, HNO2, N2O, SF6, and 85Kr during the dissolution cycle. The concentration time profiles of these effluents corresponded with expected release rates from the F-Canyon operations

  12. Southwestern Regional Partnership For Carbon Sequestration (Phase 2) Pump Canyon CO2- ECBM/Sequestration Demonstration, San Juan Basin, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Advanced Resources International

    2010-01-31

    Within the Southwest Regional Partnership on Carbon Sequestration (SWP), three demonstrations of geologic CO{sub 2} sequestration are being performed -- one in an oilfield (the SACROC Unit in the Permian basin of west Texas), one in a deep, unmineable coalbed (the Pump Canyon site in the San Juan basin of northern New Mexico), and one in a deep, saline reservoir (underlying the Aneth oilfield in the Paradox basin of southeast Utah). The Pump Canyon CO{sub 2}-enhanced coalbed methane (CO{sub 2}/ECBM) sequestration demonstration project plans to demonstrate the effectiveness of CO{sub 2} sequestration in deep, unmineable coal seams via a small-scale geologic sequestration project. The site is located in San Juan County, northern New Mexico, just within the limits of the high-permeability fairway of prolific coalbed methane production. The study area for the SWP project consists of 31 coalbed methane production wells located in a nine section area. CO{sub 2} was injected continuously for a year and different monitoring, verification and accounting (MVA) techniques were implemented to track the CO{sub 2} movement inside and outside the reservoir. Some of the MVA methods include continuous measurement of injection volumes, pressures and temperatures within the injection well, coalbed methane production rates, pressures and gas compositions collected at the offset production wells, and tracers in the injected CO{sub 2}. In addition, time-lapse vertical seismic profiling (VSP), surface tiltmeter arrays, a series of shallow monitoring wells with a regular fluid sampling program, surface measurements of soil composition, CO{sub 2} fluxes, and tracers were used to help in tracking the injected CO{sub 2}. Finally, a detailed reservoir model was constructed to help reproduce and understand the behavior of the reservoir under production and injection operation. This report summarizes the different phases of the project, from permitting through site closure, and gives the

  13. Isotropic, anisotropic, and borehole washout analyses in Gulf of Mexico Gas Hydrate Joint Industry Project Leg II, Alaminos Canyon well 21-A

    Science.gov (United States)

    Lee, Myung W.

    2012-01-01

    Through the use of three-dimensional seismic amplitude mapping, several gas hydrate prospects were identified in the Alaminos Canyon area of the Gulf of Mexico. Two of the prospects were drilled as part of the Gulf of Mexico Gas Hydrate Joint Industry Program Leg II in May 2009, and a suite of logging-while-drilling logs was acquired at each well site. Logging-while-drilling logs at the Alaminos Canyon 21–A site indicate that resistivities of approximately 2 ohm-meter and P-wave velocities of approximately 1.9 kilometers per second were measured in a possible gas-hydrate-bearing target sand interval between 540 and 632 feet below the sea floor. These values are slightly elevated relative to those measured in the hydrate-free sediment surrounding the sands. The initial well log analysis is inconclusive in determining the presence of gas hydrate in the logged sand interval, mainly because large washouts in the target interval degraded well log measurements. To assess gas-hydrate saturations, a method of compensating for the effect of washouts on the resistivity and acoustic velocities is required. To meet this need, a method is presented that models the washed-out portion of the borehole as a vertical layer filled with seawater (drilling fluid). Owing to the anisotropic nature of this geometry, the apparent anisotropic resistivities and velocities caused by the vertical layer are used to correct measured log values. By incorporating the conventional marine seismic data into the well log analysis of the washout-corrected well logs, the gas-hydrate saturation at well site AC21–A was estimated to be in the range of 13 percent. Because gas hydrates in the vertical fractures were observed, anisotropic rock physics models were also applied to estimate gas-hydrate saturations.

  14. Southwestern Regional Partnership For Carbon Sequestration (Phase 2): Pump Canyon CO2-ECBM/Sequestration Demonstration, San Juan Basin, New Mexico

    International Nuclear Information System (INIS)

    Within the Southwest Regional Partnership on Carbon Sequestration (SWP), three demonstrations of geologic CO2 sequestration are being performed -- one in an oilfield (the SACROC Unit in the Permian basin of west Texas), one in a deep, unmineable coalbed (the Pump Canyon site in the San Juan basin of northern New Mexico), and one in a deep, saline reservoir (underlying the Aneth oilfield in the Paradox basin of southeast Utah). The Pump Canyon CO2-enhanced coalbed methane (CO2/ECBM) sequestration demonstration project plans to demonstrate the effectiveness of CO2 sequestration in deep, unmineable coal seams via a small-scale geologic sequestration project. The site is located in San Juan County, northern New Mexico, just within the limits of the high-permeability fairway of prolific coalbed methane production. The study area for the SWP project consists of 31 coalbed methane production wells located in a nine section area. CO2 was injected continuously for a year and different monitoring, verification and accounting (MVA) techniques were implemented to track the CO2 movement inside and outside the reservoir. Some of the MVA methods include continuous measurement of injection volumes, pressures and temperatures within the injection well, coalbed methane production rates, pressures and gas compositions collected at the offset production wells, and tracers in the injected CO2. In addition, time-lapse vertical seismic profiling (VSP), surface tiltmeter arrays, a series of shallow monitoring wells with a regular fluid sampling program, surface measurements of soil composition, CO2 fluxes, and tracers were used to help in tracking the injected CO2. Finally, a detailed reservoir model was constructed to help reproduce and understand the behavior of the reservoir under production and injection operation. This report summarizes the different phases of the project, from permitting through site closure, and gives the results of the different MVA techniques.

  15. California State Waters Map Series—Monterey Canyon and vicinity, California

    Science.gov (United States)

    Dartnell, Peter; Maier, Katherine L.; Erdey, Mercedes D.; Dieter, Bryan E.; Golden, Nadine E.; Johnson, Samuel Y.; Hartwell, Stephen R.; Cochrane, Guy R.; Ritchie, Andrew C.; Finlayson, David P.; Kvitek, Rikk G.; Sliter, Ray W.; Greene, H. Gary; Davenport, Clifton W.; Endris, Charles A.; Krigsman, Lisa M.; Dartnell, Peter; Cochran, Susan A.

    2016-06-10

    IntroductionIn 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration, interpretation, and visualization of swath bathymetry data, acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles, and bottom-sediment sampling data. The map products display seafloor morphology and character, identify potential marine benthic habitats, and illustrate both the surficial seafloor geology and shallow subsurface geology.The Monterey Canyon and Vicinity map area lies within Monterey Bay in central California. Monterey Bay is one of the largest embayments along the west coast of the United States, spanning 36 km from its northern to southern tips (in Santa Cruz and Monterey, respectively) and 20 km along its central axis. Not only does it contain one of the broadest sections of continental shelf along California’s coast, it also contains Monterey Canyon, one of the largest and deepest submarine canyons in the world. Note that the California’s State Waters limit extends farther offshore between Santa Cruz and Monterey so that it encompasses all of Monterey Bay.The coastal area within the map area is lightly populated. The community of Moss Landing (population, 204) hosts the largest commercial fishing fleet in Monterey Bay in its harbor. The map area also includes parts of the cities of Marina (population, about 20,000) and Castroville (population, about 6,500). Fertile lowlands of the Salinas River and Pajaro River valleys largely occupy the inland part of the map area, and land use is primarily agricultural.The offshore part of the map area lies completely within the Monterey Bay National Marine Sanctuary. The

  16. Nitrogen Eutrophication on the Colorado Plateau: Using Biological Indicators to Detect Nutrient Enrichment in the Grand Canyon Region

    Science.gov (United States)

    Kenkel, J. A.; Johnson, N.; Hultine, K. R.; Sesnie, S.; Sisk, T.

    2012-12-01

    Human activities have more than doubled the availability of biologically reactive forms of nitrogen (N) since the industrial and agricultural revolutions. Though N is an important plant nutrient, increased deposition initiates a cascade of deleterious effects including ecosystem acidification, biodiversity loss, and increased smog and haze. Atmospheric pollution continues to threaten the air quality of the 16 Class 1 Wilderness areas on the Colorado Plateau, including Grand Canyon National Park (GCNP). However, the ecological impacts of N deposition in these historically N-limited, nutrient sensitive arid regions, are little- known. Here, we report baseline atmospheric and terrestrial responses to anthropogenic N deposition derived from vehicular exhaust in GCNP and long-range deposition from a local coal-fired power plant, the Navajo Generating Station (NGS). We used passive air samplers, natural abundance δ15N stable isotope analysis, and nutrient analysis to observe N patterns in air, soils, and pinyon pine (Pinus edulis) foliage. In GCNP, samples were collected from ten sites over an eight-month period in areas of projected low to high vehicular N deposition (i.e. distance from primary roadways). On the Paria Plateau, northeast of GCNP and in close proximity to the NGS, samples were collected along a distance gradient from the NGS, across the Plateau. In both study areas, atmospheric deposition, as well as soil and pine- needle nutrient concentrations show significant negative relationships with increased distance from N-source (pbiodiversity and air quality standards for the southwestern U.S.

  17. Streamflow and sediment-transport data, Colorado River and three tributaries in Grand Canyon, Arizona, 1983 and 1985-86

    Science.gov (United States)

    Garrett, W.B.; van de Vanter, E.K.; Graf, J.B.

    1993-01-01

    The U.S. Geological Survey collected streamflow and sediment-transport data at 5 streamflow-gaging stations on the Colorado River between Glen Canyon Dam and Lake Mead as a part of an interagency environmental study. The data were collected for about 6 mo in 1983 and about 4 mo in 1985-86; data also were collected at 3 sites on tributary streams in 1983. The data were used for development of unsteady flow-routing and sediment-transport models, sand-load rating curves, and evaluation of channel changes. For the 1983 sampling period, 1,076 composite cross-section suspended-sediment samples were analyzed; 809 of these samples were collected on the main stem of the Colorado River and 267 samples were from the tributaries. Bed-material samples were obtained at 1,988 verticals; 161 samples of material in transport near the bed (bedload) were collected to define the location of sand, gravel, and bed rock in the channel cross section; and 664 discharge measurements were made. For the 1985-86 sampling period, 765 composite cross-section suspended-sediment samples and 887 individual vertical samples from cross sections were analyzed. Bed-material samples were obtained at 531 verticals, 159 samples of bedload were collected, and 218 discharge measurements were made. All data are presented in tabular form. Some types of data also are presented in graphs to better show trends or variations. (USGS)

  18. Biologic surveys for the Sandia National Laboratories, Coyote Canyon Test Complex, Kirtland Air Force Base, Albuquerque, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, R.M. [4115 Allen Dr., Kingsville, TX (United States); Knight, P.J. [Marron and Associates, Inc., Corrales, NM (United States)

    1994-05-25

    This report provides results of a comprehensive biologic survey performed in Coyote Canyon Test Complex (CCTC), Sandia National Laboratories (SNL), Bernalillo County, New Mexico, which was conducted during the spring and summer of 1992 and 1993. CCTC is sited on land owned by the Department of Energy (DOE) and Kirtland Air Force Base and managed by SNL. The survey covered 3,760 acres of land, most of which is rarely disturbed by CCTC operations. Absence of grazing by livestock and possibly native ungulates, and relative to the general condition of private range lands throughout New Mexico, and relative to other grazing lands in central New Mexico. Widely dispersed, low intensity use by SNL as well as prohibition of grazing has probably contributed to abundance of special status species such as grama grass cactus within the CCTC area. This report evaluates threatened and endangered species found in the area, as well as comprehensive assessment of biologic habitats. Included are analyses of potential impacts and mitigative measures designed to reduce or eliminate potential impacts. Included is a summary of CCTC program and testing activities.

  19. Development of a Turbulence-Resolving, Three-dimensional, Free Water Surface Numerical Model for Recirculation Eddies in Grand Canyon

    Science.gov (United States)

    Akahori, R.; Schmeeckle, M. W.

    2005-12-01

    In the Colorado River in Grand Canyon, sand bars, which are built in recirculation areas downstream of channel expansions are valuable resources, particularly as natural habitat for endangered native fish and recreation sites for recreation. Since the closure of Glen Canyon Dam in 1963, there has been a reduction in the size of recirculation eddy bars. Simulated floods in the Colorado after tributary flood sediment input from the Paria River are being investigated as a method of rebuilding recirculation eddy beaches. Time-averaged, two-dimensional (and quasi- three-dimensional) numerical models have been employed to predict deposition during these beach/habit-building test flows. However, behind channel expansion areas, flows are strongly three-dimensional and the cross-channel flow is driven primarily by upwelling boils along the eddy fence that are neither stationary in time or space. Furthermore, these strong vertical motions along the eddy fence preclude use of the hydrostatic assumption. In this study, a non-hydrostatic three-dimensional numerical model is presented in order to calculate flow velocity in channels having rapid channel expansions. This model employs the Large Eddy Simulation (LES) turbulence modeling technique. LES uses spatial filtering to separate flows into gird scale and sub-gird scale rather than time averaging, thus it directly calculates large-scale turbulent motions. Also, this model employs a moving grid system and the Body Fitted Coordinate (BFC) system. These grid and coordinate systems allow the model to calculate time-dependent free water surface levels induced by large-scale turbulent motions. The model_fs calculation results are compared to existing experimental results of an open channel flow expansion in a laboratory flume. The comparison shows that the model succeeds to reproduce several key features of the flow, such as the temporally- and vertically-averaged horizontal recirculation eddy structure, and the time-averaged cross

  20. Seismic Imaging of the Waltham Canyon Fault, California: Comparison of Ray-Theoretical and Fresnel Volume Prestack Migration

    Science.gov (United States)

    Bauer, K.; Ryberg, T.; Fuis, G. S.; Lueth, S.

    2011-12-01

    Steep faults can be imaged by migration of reflected refractions observed in controlled-source seismic data. The processing can be focussed on the enhancement of the reflected refractions and simultaneous suppression of undesired phases. The Kirchhoff prestack migration is then applied where migration noise is suppressed by constructive stacking of multi-fold data. The Fresnel volume migration is an efficient alternative method, where smearing along isochrones (potential reflection points, partly migration noise) is limited to the first Fresnel zone in this technique. This makes the Fresnel volume migration particularly interesting for the imaging of steep faults using only low-fold data. We depeloped a ray-theroretical line drawing migration, which can be considered as the high-frequency approximation of the Fresnel volume migration. The ray-theoretical migration is less time consuming, and, hence, can be used to optimize the migration parameters before the final application of Fresnel volume migration. Another advantage of our ray-theoretical migration is possible wave field separation before and after migration. This feature can be used to optimize the pre-processing of the data before migration. We tested the prestack migration techniques with synthetic data. The methods were then applied to low-fold data collected across the SAFOD drill site near Parkfield, California. We chose five shot gathers with clear phases interpreted as reflected refractions. The phases are not obvious in shot gathers apart from the five shot locations. The resulting images show near-vertical reflector segments at 1-5 km depth, which project close to the surface track of the Waltham Canyon fault running approximately 10 km eastward and parallel to the San Andreas fault. Some more details were resolved in comparison with previous investigations. Based on modeling studies, the imaged features can be interpreted as reflections from a fault with lower internal velocities compared with the

  1. EX1206: Northeast and Mid-Atlantic Canyons Exploration on NOAA Ship Okeanos Explorer between 20121030 and 20121120

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — EX1206 was added and is now the final cruise of the 2012 season for Okeanos Explorer (EX). It will be primarily focused on further supplementing Northeast canyon...

  2. EX1205L2: Northeast Canyons and Continental Margins Exploration on NOAA Ship Okeanos Explorer between 20120728 and 20120803

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — EX1205 Leg 2 is the final cruise of the 2012 season for Okeanos Explorer (EX). It will be primarily focused on supplementing Northeast canyon and continental shelf...

  3. Road and Street Centerlines, Spring Creek Canyon, Published in 2007, 1:24000 (1in=2000ft) scale, Iron County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — , published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2007. It is described as 'Spring Creek Canyon'. The extent of...

  4. Road and Street Centerlines, Maple Canyon, Published in 2007, 1:24000 (1in=2000ft) scale, Iron County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — , published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2007. It is described as 'Maple Canyon'. The extent of these...

  5. Road and Street Centerlines, Fremont Canyon, Published in 2007, 1:24000 (1in=2000ft) scale, Iron County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — , published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2007. It is described as 'Fremont Canyon'. The extent of these...

  6. Proposed Wilderness Areas of Grand Canyon National Park, Arizona (Generated in 2003 by the Intermountain Region GIS Support Office)

    Data.gov (United States)

    National Park Service, Department of the Interior — This shapefile contains boundaries for Proposed Recommended Wilderness, Proposed Potential Wilderness, and Non-Wilderness in Grand Canyon National Park, Arizona....

  7. Digital Geologic Map of Bryce Canyon National Park and Vicinity, Utah (NPS, GRD, GRI, BRCA, BRCA digital map)

    Data.gov (United States)

    National Park Service, Department of the Interior — The Digital Geologic Map of Bryce Canyon National Park and Vicinity, Utah is composed of GIS data layers complete with ArcMap 9.3 layer (.LYR) files, two ancillary...

  8. Ecological baseline studies in Los Alamos and Guaje Canyons County of Los Alamos, New Mexico. A two-year study

    Energy Technology Data Exchange (ETDEWEB)

    Foxx, T.S. [comp.

    1995-11-01

    During the summers of 1993 and 1994, the Biological Resource Evaluations Team (BRET) of the Environmental Protection Group (ESH-8) conducted baseline studies within two canyon systems, Los Alamos and Guaje Canyons. Biological data was collected within each canyon to provide background and baseline information for Ecological Risk models. Baseline studies included establishment of permanent vegetation plots within each canyon along the elevational gradient. Then, in association with the various vegetation types, surveys were conducted for ground dwelling insects, birds, and small mammals. The stream channels associated with the permanent vegetation plots were characterized and aquatic macroinvertebrates collected within the stream monthly throughout a six-month period. The Geographic Position System (GPS) in combination with ARC INFO was used to map the study areas. Considerable data was collected during these surveys and are summarized in individual chapters.

  9. Sedimentary processes and triggering mechanisms of debris flows in subaquatic canyons in Rhone delta (Lake Geneva, Switzerland, France)

    Science.gov (United States)

    Corella, J. P.; Loizeau, J. L.; Le Dantec, N.; Sastre, V.; Anselmetti, F. S.; Stark, N.; del Sontro, T.; Girardclos, S.

    2012-04-01

    Subaquatic canyons in deltas are major pathways for the transport of particles from land to the deep basins. They represent active environments with frequent deltaic failures and mass-movement deposits potentially leading to hazardous (tsunami waves) and economic (infrastructure damages) implications. Understanding sedimentary processes and mass-movement triggering mechanisms is crucial to assess related consequences and to carry out geological risk assessments. The Rhone River delta in Lake Geneva (Switzerland, France) is a complex underwater structure with several active and inactive subaquatic canyons, similar to marine deltas but at a smaller scale. The difference between two bathymetric surveys in 1986 and 2002 revealed an inversion in the topography of the distal active canyon, as a former distal canyon was transformed into a mound-like structure. A 12 m-thick layer was deposited in the canyon and modified the sediment transfer conduit. Sediment cores from this deposit were retrieved in-situ in 2002 and 2011 via the "F.-A. Forel" and Russian MIR submersibles, respectively. These cores contained a homogeneous, sandy material. Its sediment texture, grain-size, high density and shear strength, and low water content suggests that it corresponds to a debris-flow deposit that possibly took place after the initiation of a mass movement due to a scarp failure in proximal areas of the canyon. In addition, in-situ geotechnical tests on the modern canyon floor have shown a soft top layer above a stiffer substratum. This soft layer, which increases in thickness towards distal areas, may act as a basal surface for hydroplaning, and might have allowed the debrite to be transported ~9 km away from the source of the scarp failure. Similarities in textures and grain-size of the debris flow and levee deposits hints at proximal northern levee as the source of this material. Rapid sediment loading in this area, at the rate of >3cm/yr, steep slopes in the canyon walls and

  10. Data from synoptic water-quality studies on the Colorado River in the Grand Canyon, Arizona, November 1990 and June 1991

    Science.gov (United States)

    Taylor, H.E.; Peart, D.B.; Antweiler, R.C.; Brinton, T.I.; Campbell, W.L.; Barbarino, J.R.; Roth, D.A.; Hart, R.J.; Averett, R.C.

    1996-01-01

    Two water-quality synoptic studies were made on the Colorado River in the Grand Canyon, Arizona. Field measurements and the collection of water samples for laboratory analysis were made at 10 mainstem and 6 tributary sites every 6 hours for a 48-hour period on November 5-6, 1990, and again on June 18-20, 1991. Field measurements included discharge, alkalinity, water temperature, light penetration, pH, specific conductance, and dissolved oxygen. Water samples were collected for the laboratory analysis of major and minor ions (calcium, magnesium, sodium, potassium, strontium, chloride, sulfate, silica as SiO2), trace elements (aluminum, arsenic, boron, barium, beryllium, cadmium, cobalt, chromium, copper, iron, lead, lithium, manganese, molybdenum, nickel, selenium, thallium, uranium, vanadium and zinc), and nutrients (phosphate, nitrate, ammonium, nitrite, total dissolved nitrogen, total dissolved phosphorus and dissolved organic carbon). Biological measurements included drift (benthic invertebrates and detrital material), and benthic invertebrates from the river bottom.

  11. Space-for-time substitution and the evolution of a submarine canyon-channel system in a passive progradational margin

    Science.gov (United States)

    Micallef, Aaron; Ribó, Marta; Canals, Miquel; Puig, Pere; Lastras, Galderic; Tubau, Xavier

    2014-09-01

    Space-for-time substitution is a concept that has been widely applied, but not thoroughly tested, in some fields of geomorphology. The objective of this study is to test whether the concept of space-for-time substitution is valid in reconstructing the evolution of a submarine canyon-channel system in a passive progradational margin. We use multibeam echosounder data and in situ measurements from the south Ebro Margin to analyse the morphology and morphometry of a sequence of submarine valleys ordered in terms of increasing valley thalweg length. The morphological model of submarine valley evolution that we can propose from this analysis is very similar to established models in the literature, which leads us to conclude that time can be substituted by space when reconstructing the evolution of submarine canyon and channel systems in the south Ebro Margin. By extracting morphometric information from the application of the space-for-time substitution model to our data, we identify a series of morphological patterns as a submarine canyon evolves in a passive progradational margin. These include the geometric similarity of canyon planform shape, an increase in canyon draining efficiency and in the influence of flank slope failures, and an evolution towards equilibrium between canyon form and imposed water and sediment load without net erosion or deposition taking place. We also observe that canyon elongation is higher downslope and that the canyon undergoes an early stage of rapid incision similar to the process of "erosion narrowing" reported in terrestrial rivers. We demonstrate that the conclusions of our study are not limited to submarine valleys in the south Ebro Margin but are applicable to other margins around the world.

  12. Evaluation of a Laser-Acoustic System for Continuously Monitoring Suspended-Sediment Concentration and Grain Size in the Colorado River in Grand Canyon

    Science.gov (United States)

    Topping, D. J.; Melis, T. S.; Rubin, D. M.

    2003-12-01

    Sandbars and other sandy deposits in and along the Colorado River in Grand Canyon National Park (GCNP) were an integral part of the pre-dam riverscape, and are important for habitat, protecting archeological sites, and recreation. These deposits have eroded substantially following the 1963 closure of Glen Canyon Dam that reduced the supply of sand at the upstream boundary of GCNP by about 94%; sandbars in the upstream portion of Grand Canyon have decreased in size by about 25% during only the last 15 years. Recent work has shown that sand transport in the post-dam river is supply limited, and is equally regulated by the discharge of water and short-term changes in the grain size of sand available for transport. During and following tributary floods, fine sand supplied to the Colorado River travels downstream as an elongating sediment wave. As the front of a sediment wave passes a given location, sand on the bed first fines and sand-transport rates increase independently of the discharge of water. Subsequently, the bed is winnowed and sand-transport rates decrease independently of discharge. By virtue of this process, sand supplied by tributaries is typically exported from the upstream portion of Grand Canyon within months under normal dam releases. Thus, newly input sand may be available to rebuild sandbars during controlled floods conducted only following large tributary floods. Accurate monitoring of sand transport in such a river requires frequent measurements of suspended-sediment concentration and grain size, and cannot be accomplished by using stable sediment-rating curves constructed from a sparser dataset of suspended-sediment measurements. To monitor sediment transport in the Colorado River, we have designed and are evaluating a laser-acoustic system for measuring the concentration and grain size of suspended sediment every 15 minutes. This system consists of (1) a subaqueously deployed laser-diffraction instrument (either a LISST 100 or a LISST 25X

  13. History of critical experiments at Pajarito Site

    Energy Technology Data Exchange (ETDEWEB)

    Paxton, H.C.

    1983-03-01

    This account describes critical and subcritical assemblies operated remotely at the Pajarito Canyon Site at the Los Alamos National Laboratory. Earliest assemblies, directed exclusively toward the nuclear weapons program, were for safety tests. Other weapon-related assemblies provided neutronic information to check detailed weapon calculations. Topsy, the first of these critical assemblies, was followed by Lady Godiva, Jezebel, Flattop, and ultimately Big Ten. As reactor programs came to Los Alamos, design studies and mockups were tested at Pajarito Site. For example, nearly all 16 Rover reactors intended for Nevada tests were preceded by zero-power mockups and proof tests at Pajarito Site. Expanded interest and capability led to fast-pulse assemblies, culminating in Godiva IV and Skua, and to the Kinglet and Sheba solution assemblies.

  14. History of critical experiments at Pajarito Site

    International Nuclear Information System (INIS)

    This account describes critical and subcritical assemblies operated remotely at the Pajarito Canyon Site at the Los Alamos National Laboratory. Earliest assemblies, directed exclusively toward the nuclear weapons program, were for safety tests. Other weapon-related assemblies provided neutronic information to check detailed weapon calculations. Topsy, the first of these critical assemblies, was followed by Lady Godiva, Jezebel, Flattop, and ultimately Big Ten. As reactor programs came to Los Alamos, design studies and mockups were tested at Pajarito Site. For example, nearly all 16 Rover reactors intended for Nevada tests were preceded by zero-power mockups and proof tests at Pajarito Site. Expanded interest and capability led to fast-pulse assemblies, culminating in Godiva IV and Skua, and to the Kinglet and Sheba solution assemblies

  15. An experiment to control nonnative fish in the Colorado River, Grand Canyon, Arizona

    Science.gov (United States)

    Coggins,, Lewis G., Jr.; Yard, Michael D.

    2011-01-01

    The humpback chub (Gila cypha) is an endangered native fish found only in the Colorado River Basin. In Grand Canyon, most humpback chub are found in the Little Colorado River and its confluence with the Colorado River. For decades, however, nonnative rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta), which prey on and compete with native fish, have dominated the Grand Canyon fish community. Between 2003 and 2006, scientists with the U.S. Geological Survey and Arizona Game and Fish Department experimentally removed 23,266 nonnative fish from a 9.4-mile-long reach of the Colorado River near where it joins the Little Colorado River. During the experiment, rainbow trout were reduced by as much as 90% and native fish abundance apparently increased in the reach. Concurrent environmental changes and a decrease in rainbow trout throughout the river make it difficult to determine if the apparent increase in native fish was the result of the experiment.

  16. Deploying a Locata network to enable precise positioning in urban canyons

    Science.gov (United States)

    Montillet, J.-P.; Roberts, G. W.; Hancock, C.; Meng, X.; Ogundipe, O.; Barnes, J.

    2009-02-01

    Locata is a new positioning technology developed by the Locata Corporation. At the beginning of 2007, the Institute of Engineering Surveying and Space Geodesy (IESSG) bought and received a network of Locata transceivers with two rovers. The purpose is to solve the challenges identified when surveying in dense multipath areas (i.e. urban canyons). In this paper, the technology is tested in an urban canyon scenario on the University park at the University of Nottingham. By comparing Locata position solutions with the true positions calculated with a total station and a carrier-phase GPS, the results show that centimetre-level accuracy is achievable in difficult environments in the presence of Wi-Fi signals. The rover’s estimated coordinates may diverge in some cases. Finally, a comparison study shows that Real Time Kinematic GPS and Locata technologies have similar accuracy when both are available.

  17. Gravity and magnetic investigations of the Ghost Dance and Solitario Canyon faults, Yucca Mountain, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Ponce, D.A.; Langenheim, V.E.

    1995-12-31

    Ground magnetic and gravity data collected along traverses across the Ghost Dance and Solitario Canyon faults on the eastern and western flanks, respectively, of Yucca Mountain in southwest Nevada are interpreted. These data were collected as part of an effort to evaluate faulting in the vicinity of a potential nuclear waste repository at Yucca Mountain. Gravity and magnetic data and models along traverses across the Ghost Dance and Solitario Canyon faults show prominent anomalies associated with known faults and reveal a number of possible concealed faults beneath the eastern flank of Yucca Mountain. The central part of the eastern flank of Yucca Mountain is characterized by several small amplitude anomalies that probably reflect small scale faulting.

  18. Klondike III/Biglow Canyon Wind Integration Project; Record of Decision, October 25, 2006.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration

    2006-10-25

    The Bonneville Power Administration (BPA) has decided to implement the Proposed Action identified in the Klondike III/Biglow Canyon Wind Integration Project Final Environmental Impact Statement (FEIS) (DOE/EIS-0374, September 2006). Under the Proposed Action, BPA will offer PPM Energy, Inc. (PPM) contract terms for interconnection of the proposed Klondike III Wind Project, located in Sherman County, Oregon, with the Federal Columbia River Transmission System (FCRTS). BPA will also offer Portland General Electric (PGE)1 contract terms for interconnection of its proposed Biglow Canyon Wind Farm, also located in Sherman County, Oregon, with the FCRTS, as proposed in the FEIS. To interconnect these wind projects, BPA will build and operate a 12-mile long, 230-kilovolt (kV) double-circuit transmission line between the wind projects and BPA's new 230-kV John Day Substation in Sherman County, Oregon. BPA will also expand its existing 500-kV John Day Substation.

  19. Gravity and magnetic investigations of the Ghost Dance and Solitario Canyon faults, Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Ground magnetic and gravity data collected along traverses across the Ghost Dance and Solitario Canyon faults on the eastern and western flanks, respectively, of Yucca Mountain in southwest Nevada are interpreted. These data were collected as part of an effort to evaluate faulting in the vicinity of a potential nuclear waste repository at Yucca Mountain. Gravity and magnetic data and models along traverses across the Ghost Dance and Solitario Canyon faults show prominent anomalies associated with known faults and reveal a number of possible concealed faults beneath the eastern flank of Yucca Mountain. The central part of the eastern flank of Yucca Mountain is characterized by several small amplitude anomalies that probably reflect small scale faulting

  20. Modelling air pollution abatement in deep street canyons by means of air scrubbers

    CERN Document Server

    De Giovanni, Marina; Avveduto, Alessandro; Pace, Lorenzo; Salisburgo, Cesare Dari; Giammaria, Franco; Monaco, Alessio; Spanto, Giuseppe; Tripodi, Paolo

    2015-01-01

    Deep street canyons are characterized by weak ventilation and recirculation of air. In such environment, the exposure to particulate matter and other air pollutants is enhanced, with a consequent worsening of both safety and health. The main solution adopted by the international community is aimed at the reduction of the emissions. In this theoretical study, we test a new solution: the removal of air pollutants close to their sources by a network of Air Pollution Abatement (APA) devices. The APA technology depletes gaseous and particulate air pollutants by a portable and low-consuming scrubbing system, that mimics the processes of wet and dry deposition. We estimate the potential pollutant abatement efficacy of a single absorber by Computational Fluid Dynamics (CFD) method. The presence of the scrubber effectively creates an additional sink at the bottom of the canyon, accelerating its cleaning process by up to 70%, when an almost perfect scrubber (90% efficiency) is simulated. The efficacy of absorber is not...

  1. Wildlife Impact Assessment: Anderson Ranch, Black Canyon, and Boise Diversion Projects, Idaho. Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Meuleman, G. Allyn

    1986-05-01

    This report presents an analysis of impacts on wildlife and their habitats as a result of construction and operation of the US Bureau of Reclamation's Anderson Ranch, Black Canyon, and Boise Diversion Projects in Idaho. The objectives were to: (1) determine the probable impacts of development and operation of the Anderson Ranch, Black Canyon, and Boise Diversion Projects to wildlife and their habitats; (2) determine the wildlife and habitat impacts directly attributable to hydroelectric development and operation; (3) briefly identify the current major concerns for wildlife in the vicinities of the hydroelectric projects; and (4) provide for consultation and coordination with interested agencies, tribes, and other entities expressing interest in the project.

  2. DISSOLUTION OF FB-LINE METAL RESIDUES CONTAINING BERYLLIUM IN H-CANYON

    Energy Technology Data Exchange (ETDEWEB)

    Rudisill, T; Mark Crowder, M; Michael Bronikowski, M

    2005-07-15

    Scrap materials containing plutonium (Pu) metal from FB-Line vaults are currently being dissolved in HB-Line for subsequent disposition through the H-Canyon facility. However, milestone and schedule commitments may require the dissolution of material containing Pu and beryllium (Be) metals in H-Canyon. To support this option, a flowsheet for dissolving Pu and Be metals in H-Canyon was demonstrated using a 4 M nitric acid (HNO{sub 3}) solution containing 0.3 M fluoride (F{sup -}). The F{sup -} was added as calcium fluoride (CaF{sub 2}). The dissolving solution also contained 2.5 g/L boron (B), a nuclear safety contingency for the H-Canyon dissolver, and 3.9 g/L iron (Fe) to represent the dissolution of carbon steel cans. The solution was heated to 90-95 C during the 8 h dissolution cycle. Dissolution of the Be metal appeared to begin as soon as the samples were added to the dissolver. Clear, colorless bubbles generated on the surface were observed and were attributed primarily to the generation of hydrogen (H{sub 2}) gas. The generation of nitrogen dioxide (NO{sub 2}) gas was also evident from the color of the solution. Essentially all of the Pu and Be dissolved during the first hour of the dissolution as the solution was heated to 90-95 C. The amount of residual solids collected following the dissolution was < 2% of the total metal charged to the dissolver. Examination of residual solids by scanning electron microscopy (SEM) showed that the largest dimension of the particles was less than 50 {micro}m with particles of smaller dimensions being more abundant. Energy dispersive spectra from spots on some of the particles showed the solids consisted of a small amount of undissolved material, corrosion products from the glassware, and dried salts from the dissolving solution.

  3. Mineral resources of the Little High Rock Canyon Wilderness Study Area, Humboldt and Washoe counties, Nevada

    International Nuclear Information System (INIS)

    The Little High Rock Canyon Wilderness Study Area consists of approximately 52,143 acres of flat-lying Tertiary volcanic rocks and associated sediments. No resources were identified in the study area, but three areas contain moderate potential for epithermal gold and silver resources. The rest of the area has low potential for epithermal gold and silver resources. The study area also contains three small areas of low potential for perlite, pozzolan, and uranium

  4. Dissolution of Plutonium Scrub Alloy and Anode Heel Materials in H-Canyon

    International Nuclear Information System (INIS)

    H-Canyon has a ''gap'' in dissolver operations during the last three months of FY03. One group of material to be processed during the gap is pre-existing scrub alloy material. There are 14 cans of material containing approximately 3.8 kilograms of plutonium. Of the 14 cans, it was anticipated that four cans contain salts, two cans contain anode heel materials, and eight cans contain scrub alloy buttons. H-Canyon desires to process the materials using a flowsheet similar to the SS and C (sand, slag and crucible) dissolution flowsheet used in F-Canyon. The materials will be loaded into carbon steel cans and then placed into aluminum metal charging bundles. Samples were sent to Savannah River Technology Center (SRTC) for characterization and flowsheet testing -- four MSE salts, two anode heels, and seven scrub alloy buttons. SRTC dissolved and characterized each of the samples. Two of them, originally thought to be MSE salts, were found to be graphite mold materials and were unsuitable for processing in H-Canyon. Characterization studies confirmed that the identification of the remaining items as MSE salts, scrub alloy buttons, and anode heel materials was correct. The MSE salts and anode heels solids are comprised primarily of plutonium, potassium, sodium and chloride. Both the MSE salts and anode heels left behind small amounts of residual solids. The scrub alloy buttons are comprised primarily of plutonium and aluminum. The solids dissolve readily with light, effervescent gas generation at the material surface and only trace amounts of NOx generation. Of the seven button samples, four dissolved completely. Two button samples contained small amounts of tantalum that did not dissolve. The last of the seven scrub alloy samples left a trace amount of residual plutonium solids. It is anticipated that the presence of undissolved fissile material is a function of where the sample was located relative to the button surface

  5. Influence of tectonic folding on rockfall susceptibility, American Fork Canyon, Utah, USA

    OpenAIRE

    J. A. Coe; Harp, E. L.

    2007-01-01

    International audience We examine rockfall susceptibility of folded strata in the Sevier fold-thrust belt exposed in American Fork Canyon in north-central Utah. Large-scale geologic mapping, talus production data, rock-mass-quality measurements, and historical rockfall data indicate that rockfall susceptibility is correlated with limb dip and curvature of the folded, cliff-forming Mississippian limestones. On fold limbs, rockfall susceptibility increases as dip increases. This relation is ...

  6. Hydrogeology and tritium transport in Chicken Creek Canyon,Lawrence Berkeley National Laboratory, Berkeley, California

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, Preston D.; Javandel, Iraj

    2007-10-31

    This study of the hydrogeology of Chicken Creek Canyon wasconducted by the Environmental Restoration Program (ERP) at LawrenceBerkeley National Laboratory (LBNL). This canyon extends downhill fromBuilding 31 at LBNL to Centennial Road below. The leading edge of agroundwater tritium plume at LBNL is located at the top of the canyon.Tritium activities measured in this portion of the plume during thisstudy were approximately 3,000 picocuries/liter (pCi/L), which issignificantly less than the maximum contaminant level (MCL) for drinkingwaterof 20,000 pCi/L established by the Environmental ProtectionAgency.There are three main pathways for tritium migration beyond theLaboratory s boundary: air, surface water and groundwater flow. Thepurpose of this report is to evaluate the groundwater pathway.Hydrogeologic investigation commenced with review of historicalgeotechnical reports including 35 bore logs and 27 test pit/trench logsas well as existing ERP information from 9 bore logs. This was followedby field mapping of bedrock outcrops along Chicken Creek as well asbedrock exposures in road cuts on the north and east walls of the canyon.Water levels and tritium activities from 6 wells were also considered.Electrical-resistivity profiles and cone penetration test (CPT) data werecollected to investigate the extent of an interpreted alluvial sandencountered in one of the wells drilled in this area. Subsequent loggingof 7 additional borings indicated that this sand was actually anunusually well-sorted and typically deeply weathered sandstone of theOrinda Formation. Wells were installed in 6 of the new borings to allowwater level measurement and analysis of groundwater tritium activity. Aslug test and pumping tests were also performed in the wellfield.

  7. Salvia guaneorum (Labiatae), a new species from the Chicamocha Canyon, Colombia

    OpenAIRE

    Fernández Alonso, José Luis

    2014-01-01

    [EN] A new species of Salvia subgen. Calosphace from the Chicamocha Canyon, in the Eastern Cordillera of Colombia is described and illustrated. The morphological affinities and putative relatives with other Colombian species of the sections Angulatae and Longipes are discussed. [ES] Se describe e ilustra una especie nueva de Salvia subgen. Calosphace, procedente del Cañón del Chicamocha, en la Cordillera Oriental de Colombia. Se discuten sus afinidades morfológicas y posible relación con otr...

  8. Annotated bibliography for the humpback chub (Gila cypha) with emphasis on the Grand Canyon population.

    Energy Technology Data Exchange (ETDEWEB)

    Goulet, C. T.; LaGory, K. E.; Environmental Science Division

    2009-10-05

    Glen Canyon Dam is a hydroelectric facility located on the Colorado River in Arizona that is operated by the U.S. Bureau of Reclamation (Reclamation) for multiple purposes including water storage, flood control, power generation, recreation, and enhancement of fish and wildlife. Glen Canyon Dam operations have been managed for the last several years to improve conditions for the humpback chub (Gila cypha) and other ecosystem components. An extensive amount of literature has been produced on the humpback chub. We developed this annotated bibliography to assist managers and researchers in the Grand Canyon as they perform assessments, refine management strategies, and develop new studies to examine the factors affecting humpback chub. The U.S. Geological Survey recently created a multispecies bibliography (including references on the humpback chub) entitled Bibliography of Native Colorado River Big Fishes (available at www.fort.usgs.gov/Products/data/COFishBib). That bibliography, while quite extensive and broader in scope than ours, is not annotated, and, therefore, does not provide any of the information in the original literature. In developing this annotated bibliography, we have attempted to assemble abstracts from relevant published literature. We present here abstracts taken unmodified from individual reports and articles except where noted. The bibliography spans references from 1976 to 2009 and is organized in five broad topical areas, including: (1) biology, (2) ecology, (3) impacts of dam operations, (4) other impacts, and (5) conservation and management, and includes twenty subcategories. Within each subcategory, we present abstracts alphabetically by author and chronologically by year. We present relevant articles not specific to either the humpback chub or Glen Canyon Dam, but cited in other included reports, under the Supporting Articles subcategory. We provide all citations in alphabetical order in Section 7.

  9. Modelling air pollution abatement in deep street canyons by means of air scrubbers

    OpenAIRE

    De Giovanni, Marina; Curci, Gabriele; Avveduto, Alessandro; Pace, Lorenzo; Salisburgo, Cesare Dari; Giammaria, Franco; Monaco, Alessio; SPANTO, Giuseppe; Tripodi, Paolo

    2015-01-01

    Deep street canyons are characterized by weak ventilation and recirculation of air. In such environment, the exposure to particulate matter and other air pollutants is enhanced, with a consequent worsening of both safety and health. The main solution adopted by the international community is aimed at the reduction of the emissions. In this theoretical study, we test a new solution: the removal of air pollutants close to their sources by a network of Air Pollution Abatement (APA) devices. The ...

  10. Politics in an Indian Canyon? Some Thoughts on the Implications of Ethnomathematics

    Science.gov (United States)

    Pinxten, Rik; Francois, Karen

    2011-01-01

    Working with Navajo Indian informants in Arizona, USA we became aware of the capabilities of children and adults to find their way in vast and clearly "chaotic" canyons. One thing we did was describe what people actually did and said about their ways to find the way back home in such contexts. A second one was to use these data in order to build a…

  11. Deep-Sea, Deep-Sequencing: Metabarcoding Extracellular DNA from Sediments of Marine Canyons.

    Directory of Open Access Journals (Sweden)

    Magdalena Guardiola

    Full Text Available Marine sediments are home to one of the richest species pools on Earth, but logistics and a dearth of taxonomic work-force hinders the knowledge of their biodiversity. We characterized α- and β-diversity of deep-sea assemblages from submarine canyons in the western Mediterranean using an environmental DNA metabarcoding. We used a new primer set targeting a short eukaryotic 18S sequence (ca. 110 bp. We applied a protocol designed to obtain extractions enriched in extracellular DNA from replicated sediment corers. With this strategy we captured information from DNA (local or deposited from the water column that persists adsorbed to inorganic particles and buffered short-term spatial and temporal heterogeneity. We analysed replicated samples from 20 localities including 2 deep-sea canyons, 1 shallower canal, and two open slopes (depth range 100-2,250 m. We identified 1,629 MOTUs, among which the dominant groups were Metazoa (with representatives of 19 phyla, Alveolata, Stramenopiles, and Rhizaria. There was a marked small-scale heterogeneity as shown by differences in replicates within corers and within localities. The spatial variability between canyons was significant, as was the depth component in one of the canyons where it was tested. Likewise, the composition of the first layer (1 cm of sediment was significantly different from deeper layers. We found that qualitative (presence-absence and quantitative (relative number of reads data showed consistent trends of differentiation between samples and geographic areas. The subset of exclusively benthic MOTUs showed similar patterns of β-diversity and community structure as the whole dataset. Separate analyses of the main metazoan phyla (in number of MOTUs showed some differences in distribution attributable to different lifestyles. Our results highlight the differentiation that can be found even between geographically close assemblages, and sets the ground for future monitoring and conservation

  12. Black bears in Canyon de Chelly National Monument: Life in a changing environment

    OpenAIRE

    Tredick, Catherine Anne

    2011-01-01

    Understanding how wildlife utilize habitat at varying scales is important for understanding and predicting potential impacts of landscape changes (e.g., habitat loss and fragmentation, restoration efforts, climate change, etc.) and in determining effective strategies for conservation and management. This research examines fine-scale and landscape-level habitat use of black bears in Canyon de Chelly National Monument (CACH), Arizona, USA in the context of large-scale landscape change. Currentl...

  13. Tales of Two Turbidity Currents Recorded in Monterey Submarine Canyon, USA

    Science.gov (United States)

    Xu, J.; Sequeiros, O.; Noble, M. A.

    2013-12-01

    The capacity of turbidity currents to carry sand and coarser sediment from shallow to deep regions in submarine environment has attracted the attention of researchers from different disciplines. Yet not only field measurements of oceanic turbidity currents are a rare achievement but also when such measurements do occur they consist mostly of velocity records with very limited or no data of suspended sediment concentration and grain size distribution. This work focus on two turbidity currents measured in the Monterey Canyon in 2002 with emphasis on suspended sediment from unique samples collected within the body of these currents. It is shown that concentration and grain size of the suspended material, defined by the source of the gravity flows, play a significant role in shaping the characteristics of the currents as they travel downstream the canyon. Before the flows reach their normal state, which is defined by bed slope, bed roughness, and suspended grain size, they might pass through an adjusting preliminary stage where they are subject to capacity-driven deposition releasing heavy material in excess. Flows composed with fine (silt/clay) sediments tend to be thicker than those with sands. The measured velocity and concentration data confirm the different flow patterns between the front and body of turbidity currents and that, even after reaching normal state, the flow regime can be radically disrupted by abrupt changes in canyon morphology.

  14. Loss of residual heat removal system: Diablo Canyon, Unit 2, April 10, 1987

    International Nuclear Information System (INIS)

    This report presents the findings of an NRC Augmented Inspection Team (AIT) investigation into the circumstances associated with the loss of residual heat removal (RHR) system capability for a period of approximately one and one-half hours at the Diablo Canyon, Unit 2 reactor facility on April 10, 1987. This event occurred while the Diablo Canyon, Unit 2, a pressurized water reactor, was shutdown with the reactor coolant system (RCS) water level drained to approximately mid-level of the hot leg piping. The reactor containment building equipment hatch was removed at the time of the event, and plant personnel were in the process of removing the primary side manways to gain access into the steam generator channel head areas. Thus, two fission product barriers were breached throughout the event. The RCS temperature increased from approximately 870F to bulk boiling conditions without RCS temperature indication available to the plant operators. The RCS was subsequently pressurized to approximately 7 to 10 psig. The NRC AIT members concluded that the Diablo Canyon, Unit 2 plant was, at the time of the event, in a condition not previously analyzed by the NRC staff. The AIT findings from this event appear significant and generic to other pressurized water reactor facilities licensed by the NRC

  15. LETTER REPORT SUMMARY RESULTS OF THE NRC TEAM INTERACTION SKILLS STUDY AT DIABLO CANYON POWER PLANT

    Energy Technology Data Exchange (ETDEWEB)

    Hauth, J. T.; Toquam, J. L.; Bramwell, A. T.; Fleming, T. E.

    1990-12-01

    This report presents information to participants in the Team Interaction Skills study conducted at Diablo Canyon Power Plant from September to November 1989. A study was conducted to develop and assess measures of team interaction skills of nuclear power plant control room crews in simulated emergency conditions. Data were collected at a boiling water reactor (BWR) and pressurized water reactor (PWA) using three sets of rating scales; Behaviorally Anchored Rating Scales (BARS), Behavioral Frequency rating scales, and Technical Performance rating scales. Diablo Canyon Power Plant agreed to serve as the PWR plant in the study. Obse!Vers consisting of contract license examiners, Diablo Canyon Power Plant training instructors, and project staff used the rating scales to provide assessments of team interaction skills and technical skills of control room crews during emerg-3ncy scenarios as part of license requalification training. Crew members were also asked to providH self-ratings of their performance to gather information regarding crew responses to the Team Interactions Skills rating scales.

  16. The impact of traffic-flow patterns on air quality in urban street canyons.

    Science.gov (United States)

    Thaker, Prashant; Gokhale, Sharad

    2016-01-01

    We investigated the effect of different urban traffic-flow patterns on pollutant dispersion in different winds in a real asymmetric street canyon. Free-flow traffic causes more turbulence in the canyon facilitating more dispersion and a reduction in pedestrian level concentration. The comparison of with and without a vehicle-induced-turbulence revealed that when winds were perpendicular, the free-flow traffic reduced the concentration by 73% on the windward side with a minor increase of 17% on the leeward side, whereas for parallel winds, it reduced the concentration by 51% and 29%. The congested-flow traffic increased the concentrations on the leeward side by 47% when winds were perpendicular posing a higher risk to health, whereas reduced it by 17-42% for parallel winds. The urban air quality and public health can, therefore, be improved by improving the traffic-flow patterns in street canyons as vehicle-induced turbulence has been shown to contribute significantly to dispersion. PMID:26412198

  17. Heavy mineral sorting in downwards injected Palaeocene sandstone, Siri Canyon, Danish North Sea

    Science.gov (United States)

    Kazerouni, Afsoon Moatari; Friis, Henrik; Svendsen, Johan Byskov; Weibel, Rikke

    2011-05-01

    Post-depositional remobilization and injection of sand are often seen in deep-water clastic systems and have been recently recognised as a significant modifier of deep-water sandstone geometry. Large scale injectite complexes have been interpreted from borehole data in the Palaeocene Siri Canyon near the Danish Central Graben of the North Sea hydrocarbon province. The emplacement of large scale injectite complexes has been commonly attributed to seismic activity and consequent sand liquefaction. However, due to very small differences in textural and compositional properties, and the lack of depositional structures in deep-water sandstones, the distinction between "in situ" and injected or remobilized sandstones is often ambiguous. Large scale heavy mineral sorting (in 10 m thick units) is observed in several reservoir units in the Siri Canyon and has been interpreted to represent the depositional sorting. In this study we describe an example of effective shear-zone sorting of heavy minerals in a thin downwards injected sandstone dyke which was encountered in one of the cores in the Cecilie Field, Siri Canyon. Differences in sorting pattern of heavy minerals are suggested as a tool for petrographic/geochemical distinction between "in situ" sandstones and their related injectites, especially where primary sedimentary structures are removed by fluidization or minor remobilization.

  18. Ecosystem Modeling for Evaluation of Adaptive Management Policies in the Grand Canyon

    Directory of Open Access Journals (Sweden)

    Lawrence E. Stevens

    2000-12-01

    Full Text Available An Adaptive Environmental Assessment and Management workshop process was used to assist Grand Canyon scientists and managers in developing conceptual and simulation models for the Colorado ecosystem affected by Glen Canyon Dam. This model examines ecosystem variables and processes at multiple scales in space and time, ranging from feet and hours for benthic algal response to diurnal flow changes, to reaches and decades for sediment storage and dynamics of long-lived native fish species. Its aim is to help screen policy options ranging from changes in hourly variation in flow allowed from Glen Canyon Dam, to major structural changes for restoration of more natural temperature regimes. It appears that we can make fairly accurate predictions about some components of ecosystem response to policy change (e.g., autochthonous primary production, insect communities, riparian vegetation, rainbow trout population, but we are moderately or grossly uncertain about others (e.g., long-term sediment storage, response of native and non-native fishes to physical habitat restoration. Further, we do not believe that existing monitoring programs are adequate to detect responses of native fishes or vegetation to anything short of gross habitat changes. Some experimental manipulations (such as controlled floods for beach/habitat-building should proceed, but most should await development of better monitoring programs and sound temporal baseline information from those programs.

  19. Numerical study on the ozone formation inside street canyons using a chemistry box model

    Institute of Scientific and Technical Information of China (English)

    Chun-Ho Liu; Dennis Y. C. Leung

    2008-01-01

    Tropospheric ozone is a secondary air pollutant produced in the presence of nitrogen oxides, volatile organic compounds (VOCs), and solar radiation. In an urban environment, ground-level vehicular exhaust is the major anthropogenic source of ozone precursors. In the cases of street canyons, pollutant dilution is weakened by the surrounding buildings that create localized high concentration of nitrogen oxides and VOCs, and thus leads to high potential of ozone formation. By considering the major physical and chemical processes, a chemistry box model is employed to investigate the characteristics of ozone formation due to vehicular exhaust inside street canyons under the worst case scenario, i.e. the calm wind condition. It is found that a high level of ozone concentration, of the order of 100 ppbv and higher, would occur inside the street canyons, in particular, when the emission rate (concentration) ratio of VOCs to nitrogen oxides is greater than 10. This elevated ozone concentration appears at the transition from VOCs to nitrogen oxides sensitivity and may extend to a few hundreds.

  20. The impact of traffic-flow patterns on air quality in urban street canyons.

    Science.gov (United States)

    Thaker, Prashant; Gokhale, Sharad

    2016-01-01

    We investigated the effect of different urban traffic-flow patterns on pollutant dispersion in different winds in a real asymmetric street canyon. Free-flow traffic causes more turbulence in the canyon facilitating more dispersion and a reduction in pedestrian level concentration. The comparison of with and without a vehicle-induced-turbulence revealed that when winds were perpendicular, the free-flow traffic reduced the concentration by 73% on the windward side with a minor increase of 17% on the leeward side, whereas for parallel winds, it reduced the concentration by 51% and 29%. The congested-flow traffic increased the concentrations on the leeward side by 47% when winds were perpendicular posing a higher risk to health, whereas reduced it by 17-42% for parallel winds. The urban air quality and public health can, therefore, be improved by improving the traffic-flow patterns in street canyons as vehicle-induced turbulence has been shown to contribute significantly to dispersion.

  1. Eleventh-century shift in timber procurement areas for the great houses of Chaco Canyon.

    Science.gov (United States)

    Guiterman, Christopher H; Swetnam, Thomas W; Dean, Jeffrey S

    2016-02-01

    An enduring mystery from the great houses of Chaco Canyon is the origin of more than 240,000 construction timbers. We evaluate probable timber procurement areas for seven great houses by applying tree-ring width-based sourcing to a set of 170 timbers. To our knowledge, this is the first use of tree rings to assess timber origins in the southwestern United States. We found that the Chuska and Zuni Mountains (>75 km distant) were the most likely sources, accounting for 70% of timbers. Most notably, procurement areas changed through time. Before 1020 Common Era (CE) nearly all timbers originated from the Zunis (a previously unrecognized source), but by 1060 CE the Chuskas eclipsed the Zuni area in total wood imports. This shift occurred at the onset of Chaco florescence in the 11th century, a time with substantial expansion of existing great houses and the addition of seven new great houses in the Chaco Core area. It also coincides with the proliferation of Chuskan stone tools and pottery in the archaeological record of Chaco Canyon, further underscoring the link between land use and occupation in the Chuska area and the peak of great house construction. Our findings, based on the most temporally specific and replicated evidence of Chacoan resource procurement obtained to date, corroborate the long-standing but recently challenged interpretation that large numbers of timbers were harvested and transported from distant mountain ranges to build the great houses at Chaco Canyon. PMID:26644552

  2. Seismic profile analysis of sediment deposits in Brownlee and Hells Canyon Reservoirs near Cambridge, Idaho

    Science.gov (United States)

    Flocks, James; Kelso, Kyle; Fosness, Ryan; Welcker, Chris

    2014-01-01

    The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center, in cooperation with the USGS Idaho Water Science Center and the Idaho Power Company, collected high-resolution seismic reflection data in the Brownlee and Hells Canyon Reservoirs, in March of 2013.These reservoirs are located along the Snake River, and were constructed in 1958 (Brownlee) and 1967 (Hells Canyon). The purpose of the survey was to gain a better understanding of sediment accumulation within the reservoirs since their construction. The chirp system used in the survey was an EdgeTech Geo-Star Full Spectrum Sub-Bottom (FSSB) system coupled with an SB-424 towfish with a frequency range of 4 to 24 kHz. Approximately 325 kilometers of chirp data were collected, with water depths ranging from 0-90 meters. These reservoirs are characterized by very steep rock valley walls, very low flow rates, and minimal sediment input into the system. Sediments deposited in the reservoirs are characterized as highly fluid clays. Since the acoustic signal was not able to penetrate the rock substrate, only the thin veneer of these recent deposits were imaged. Results from the seismic survey indicate that throughout both of the Brownlee and Hells Canyon reservoirs the accumulation of sediments ranged from 0 to 2.5 m, with an average of 0.5 m. Areas of above average sediment accumulation may be related to lower slope, longer flooding history, and proximity to fluvial sources.

  3. Oxygen isotopes and trace elements in the Tiva Canyon Tuff, Yucca Mountain and vicinity, Nye County, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, B.D.; Kyser, T.K.; Peterman, Z.E.

    1996-12-31

    Yucca Mountain is being studied as a potential site for an underground repository for high-level radioactive waste. Because Yucca Mountain is located in a resource-rich geologic setting, one aspect of the site characterization studies is an evaluation of the resource potential at Yucca Mountain. The Tiva Canyon Tuff (TCT) is a widespread felsic ash-flow sheet that is well exposed in the Yucca Mountain area. Samples of the upper part of the TCT were selected to evaluate the potential for economic mineral deposits within the Miocene volcanic section. These samples of the upper cliff and caprock subunits have been analyzed for oxygen isotopes and a large suite of elements. Oxygen isotope compositions ({delta}{sup 18}O) of the TCT are typical of felsic igneous rocks but range from 6.9 to 11.8 permil, indicating some post-depositional alteration. There is no evidence of the low {delta}{sup 18}O values (less than 6 permil) that are typical of epithermal precious-metal deposits in the region. The variation in oxygen isotope ratios is probably the result of deuteric alteration during late-stage crystallization of silica and low-temperature hydration of glassy horizons; these processes are also recorded by the chemical compositions of the rocks. However, most elemental contents in the TCT reflect igneous processes, and the effects of alteration are observed only in some of the more mobile elements. These studies indicate that the TCT at Yucca Mountain has not been affected by large-scale meteoric-water hydrothermal circulation. The chemical compositions of the TCT, especially the low concentrations of most trace elements including typical pathfinder elements, show no evidence for epithermal metal deposits. Together, these data indicate that the potential for economic mineralization in this part of the volcanic section at Yucca Mountain is small.

  4. Overview of ''Red Oil'' Frequency Analyses for F-Canyon

    International Nuclear Information System (INIS)

    A very small potential exists in the Savannah River Site (SRS) separations operations for an uncontrolled reaction between tri-n-butyl phosphate (TBP) and nitric acid that could result in unacceptable damage to separations facilities and a significant release of radioactive materials. The recent ''red oil'' (TBP and nitric acid) accident in Tomsk, Russia, resulted in considerable damage and radioactive release. Explosions have also occurred at SRS during the early years of operations. While the SRS separations facilities have operated without incident for many years, it is prudent to revisit the SRS defense-in-depth approach to preventing such an accident and to upgrade preventive procedures and hardware as appropriate

  5. Sedimentation in Rio La Venta Canyon in Netzahualcoyotl Reservoir, Chiapas, Mexico

    Science.gov (United States)

    de La Fuente, J. A.; Lisle, T.; Velasquez, J.; Allison, B. L.; Miller, A.

    2002-12-01

    Sedimentation of Rio La Venta as it enters the Netzahualcoyotl Reservoir in Chiapas, Mexico, threatens a unique part of the aquatic ecosystem. Rio La Venta enters the reservoir via a narrow canyon about 16 km long with spectacular, near-vertical limestone bluffs up to 320 m high and inhabited by the flora and fauna of a pristine tropical forest. Karst terrain underlies most of the Rio La Venta basin in the vicinity of the reservoir, while deeply weathered granitic terrain underlies the Rio Negro basin, and the headwaters of the Rio La Venta to the south. The Rio Negro joins Rio La Venta 3 km downstream of the upper limit of the reservoir and delivers the bulk of the total clastic sediment (mostly sand and finer material). The canyon and much of the contributing basin lie within the Reserva de la Biosfera, Selva El Ocote, administered by the Comision Nacional de Areas Naturales Protegidas, part of the Secretaria de Medioambiente y Recursos Naturales. The Klamath National Forest Forest has cooperated with its Mexican counterparts since 1993 in natural resource management, neo-tropical bird inventories, wildfire management, and more recently in watershed analyses. Rates of sedimentation are estimated from bathymetric surveys conducted in March, 2002. A longitudinal profile down the inundated canyon during a high reservoir level shows an inflection from a slope of 0.0017 to one of 0.0075 at 7.2 km downstream of the mouth of Rio Negro. The bed elevation at this point corresponds to the lowest reservoir level, suggesting that the gentler sloping bed upstream is formed by fluvial processes during drawdown and that downstream by pluvial processes. Using accounts that boats could access Rio Negro during low water levels in 1984, we estimate an annual sedimentation rate of roughly 3 million cubic meters per year. This suggests that boats might no longer be able to access the most spectacular section of canyon upstream of Rio Negro within a decade, depending on how the

  6. The Glen Canyon Dam Adaptive Management Program: An experiment in science-based resource management

    Science.gov (United States)

    kaplinski, m

    2001-12-01

    In 1996, Glen Canyon Dam Adaptive Management (GCDAMP) program was established to provide input on Glen Canyon Dam operations and their affect on the Colorado Ecosystem in Grand Canyon. The GCDAMP is a bold experiment in federal resource management that features a governing partnership with all relevant stakeholders sitting at the same table. It is a complicated, difficult process where stakeholder-derived management actions must balance resource protection with water and power delivery compacts, the Endangered Species Act, the National Historical Preservation Act, the Grand Canyon Protection Act, National Park Service Policy, and other stakeholder concerns. The program consists of four entities: the Adaptive Management Workgroup (AMWG), the Technical Workgroup (TWG), the Grand Canyon Monitoring and Research Center (GCMRC), and independent review panels. The AMWG and TWG are federal advisory committees that consists of federal and state resource managers, Native American tribes, power, environmental and recreation interests. The AMWG is develops, evaluates and recommends alternative dam operations to the Secretary. The TWG translates AMWG policy and goals into management objectives and information needs, provides questions that serve as the basis for long-term monitoring and research activities, interprets research results from the GCMRC, and prepares reports as required for the AMWG. The GCMRC is an independent science center that is responsible for all GCDAMP monitoring and research activities. The GCMRC utilizes proposal requests with external peer review and an in-house staff that directs and synthesizes monitoring and research results. The GCMRC meets regularly with the TWG and AMWG and provides scientific information on the consequences of GCDAMP actions. Independent review panels consist of external peer review panels that provide reviews of scientific activities and the program in general, technical advice to the GCMRC, TWG and AMWG, and play a critical

  7. The influence of controlled floods on fine sediment storage in debris fan-affected canyons of the Colorado River basin

    Science.gov (United States)

    Mueller, Erich R.; Grams, Paul E.; Schmidt, John C.; Hazel, Joseph E., Jr.; Alexander, Jason S.; Kaplinski, Matt

    2014-01-01

    Prior to the construction of large dams on the Green and Colorado Rivers, annual floods aggraded sandbars in lateral flow-recirculation eddies with fine sediment scoured from the bed and delivered from upstream. Flows greater than normal dam operations may be used to mimic this process in an attempt to increase time-averaged sandbar size. These controlled floods may rebuild sandbars, but sediment deficit conditions downstream from the dams restrict the frequency that controlled floods produce beneficial results. Here, we integrate complimentary, long-term monitoring data sets from the Colorado River in Marble and Grand Canyons downstream from Glen Canyon dam and the Green River in the Canyon of Lodore downstream from Flaming Gorge dam. Since the mid-1990s, several controlled floods have occurred in these canyon rivers. These controlled floods scour fine sediment from the bed and build sandbars in eddies, thus increasing channel relief. These changes are short-lived, however, as interflood dam operations erode sandbars within several months to years. Controlled flood response and interflood changes in bed elevation are more variable in Marble Canyon and Grand Canyon, likely reflecting more variable fine sediment supply and stronger transience in channel bed sediment storage. Despite these differences, neither system shows a trend in fine-sediment storage during the period in which controlled floods were monitored. These results demonstrate that controlled floods build eddy sandbars and increase channel relief for short interflood periods, and this response may be typical in other dam-influenced canyon rivers. The degree to which these features persist depends on the frequency of controlled floods, but careful consideration of sediment supply is necessary to avoid increasing the long-term sediment deficit.

  8. Thermal comfort in an east-west oriented street canyon in Freiburg (Germany) under hot summer conditions

    Science.gov (United States)

    Ali-Toudert, F.; Mayer, H.

    2007-01-01

    Field-measurements were conducted in an urban street canyon with an east-west orientation, and a height-to-width ratio H/W = 1 during cloudless summer weather in 2003 in Freiburg, Germany. This experimental work adds to the knowledge available on the microclimate of an urban canyon and its impact on human comfort. Air temperature T a , air humidity VP, wind speed v and direction dd were measured continuously. All short-wave and long-wave radiation fluxes from the 3D surroundings were also measured. The degree of comfort was defined in terms of physiologically equivalent temperature (PET). Furthermore, the data gathered within the canyon were compared to data collected by a permanent urban climate station with the aim of furthering the understanding of microclimatic changes due to street geometry. Changes in the meteorological variables T a , v and dd in the canyon in comparison to an unobstructed roof level location were found to be in good agreement with previous studies, i.e., a small increase of T a in the canyon adjacent to irradiated surfaces, and a good correlation of v and dd between canyon and roof levels. The daily dynamics of canyon facet irradiances and their impacts on the heat gained by a pedestrian were strongly dependent on street geometry and orientation. Thermal stress was mostly attributable to solar exposure. Under cloudless summer weather, a standing body was found to absorb, on average, 74% of heat in the form of long-wave irradiance and 26% as short-wave irradiance. Shading the pedestrian as well as the surrounding surfaces is, hence, the first strategy in mitigating heat stress in summer under hot conditions.

  9. Numerical Study on the Impact of Ground Heating and Ambient Wind Speed on Flow Fields in Street Canyons

    Institute of Scientific and Technical Information of China (English)

    LI Lei; YANG Lin; ZHANG Li-Jie; JIANG Yin

    2012-01-01

    The impact of ground heating on flow fields in street canyons under different ambient wind speed conditions was studied based on numerical methods.A series of numerical tests were performed,and three factors including height-to-width (H/W) ratio,ambient wind speed and ground heating intensity were taken into account.Three types of street canyon with H/W ratios of 0.5,1.0 and 2.0,respectively,were used in the simulation and seven speed values ranging from 0.0 to 3.0 m s-1 were set for the ambient wind speed.The ground heating intensity,which was defined as the difference between the ground temperature and air temperature,ranged from 10 to 40 K with an increase of 10 K in the tests.The results showed that under calm conditions,ground heating could induce circulation with a wind speed of around 1.0 m s-1,which is enough to disperse pollutants in a street canyon.It was also found that an ambient wind speed threshold may exist for street canyons with a fixed H/W ratio.When ambient wind speed was lower than the threshold identified in this study,the impact of the thermal effect on the flow field was obvious,and there existed a multi-vortex flow pattern in the street canyon.When the ambient wind speed was higher than the threshold,the circulation pattern was basically determined by dynamic effects.The tests on the impact of heating intensity showed that a higher ground heating intensity could strengthen the vortical flow within the street canyon,which would help improve pollutant diffusion capability in street canyons.

  10. Paleomagnetism and magnetostratigraphy of the lower Glen Canyon and upper Chinle Groups, Jurassic-Triassic of northern Arizona and northeast Utah

    Science.gov (United States)

    Molina-Garza, Roberto S.; Geissman, John W.; Lucas, Spencer G.

    2003-04-01

    Twenty-eight selected sites (individual beds) in the Moenave Formation at the Echo Cliffs, northern Arizona, strata give a Hettangian paleomagnetic pole at 63.7°N, 59.7°E (dp = 2.6°, dm = 5.1°). The Wingate Sandstone and Rock Point Formation at Comb Ridge, southeast Utah, provide a Rhaetian paleopole at 57.4°N, 56.6°E (N = 16 sites; dp = 3.4, dm = 6.5). High unblocking temperatures (>600°C), high coercivity, and data analyses indicate that the characteristic magnetization is primarily a chemical remanence residing in hematite. The Hettangian and Rhaetian poles are statistically indistinguishable (at 95% confidence), they resemble existing data for the Glen Canyon Group, and they provide further validation to the J1 cusp of the North American apparent pole wander path (APWP). The red siltstone and upper members of the Chinle Group, on the south flank of the Uinta Mountains, northern Utah, define a Rhaetian pole at 51.6°N, 70.9°E (N = 20 sites; dp = 3.5°, dm = 6.9°). The Gartra and upper members of the Chinle Group in the north flank of the Uinta Mountains, give paleopoles at 52.0°N, 100.3°E (N = 6 sites; dp = 5.4°, dm = 10.5°) and 50.9°N, 50.1°E (N = 5 sites; dp = 8.8°, dm = 17.5°), respectively. These data indicate no significant rotation of the Uinta Mountains with respect to the craton. In total, data for the plateau and its bordering region of Cenozoic uplifts support estimates of small rotation of the plateau and provide evidence against the hypothesis of a Late Triassic standstill of the North American APWP. Our magnetostratigraphic results are consistent with lithographic and biostratigraphic data that place the Triassic-Jurassic boundary within the Dinosaur Canyon Member of the Moenave Formation, not at a regional hiatus.

  11. Direct ultimate disposal of spent fuel. Simulation of shaft transport. Study of rope slippage (TA 10)

    International Nuclear Information System (INIS)

    The test results show that rope slippage does occur occasionally in Koepe hoists, mainly with hinged loads. The countermeasures chosen in most cases include modification of the rope lubrication (coefficient of friction), of load ratios S1/S2, (ballast, reduction of payload), or organisational measures (maintenance). Results and data are reported giving evidence that with the proposed, additional measures for preventing or managing rope slippage, the designed Koepe hoist for hinged payloads up to 85 t can be operated safely without risk of damage caused by rope slippage. It is also proven that there is no need to change ballast in case of transport of varying payloads, as this will not create the risk of undue rope slippage. (orig./HP)

  12. Effects of three high-flow experiments on the Colorado River ecosystem downstream from Glen Canyon Dam, Arizona

    Science.gov (United States)

    Melis, Theodore S.

    2011-01-01

    Three high-flow experiments (HFEs) were conducted by the U.S. Department of the Interior at Glen Canyon Dam, Arizona, in March 1996, November 2004, and March 2008. These experiments, also known as artificial or controlled floods, were large-volume, scheduled releases of water from Glen Canyon Dam that were designed to mimic some aspects of pre-dam Colorado River seasonal flooding. The goal of these experiments was to determine whether high flows could be used to benefit important physical and biological resources in Glen Canyon National Recreation Area and Grand Canyon National Park that had been affected by the operation of Glen Canyon Dam. Efforts such as HFEs that seek to maintain and restore downstream resources are undertaken by the U.S. Department of the Interior under the auspices of the Grand Canyon Protection Act of 1992 (GCPA; title XVIII, secs. 1801-1809, of Public Law 102-575). Scientists conducted a wide range of monitoring and research activities before, during, and after the experiments. Initially, research efforts focused on whether HFEs could be used to rebuild and maintain Grand Canyon sandbars, which provide camping beaches for hikers and whitewater rafters, create habitats potentially used by native fish and other wildlife, and are the source of windborne sand that may help to protect some archaeological resources from weathering and erosion. As scientists gained a better understanding of how HFEs affect the physical environment, research efforts expanded to include additional investigations about the effects of HFEs on biological resources, such as native fishes, nonnative sports fishes, riverside vegetation, and the aquatic food web. The chapters that follow summarize and synthesize for decisionmakers and the public what has been learned about HFEs to provide a framework for implementing similar future experiments. This report is a product of the Glen Canyon Dam Adaptive Management Program (GCDAMP), a Federal initiative authorized to ensure

  13. Fast calculations of the spectral diffuse-to-global ratios for approximating spectral irradiance at the street canyon level

    Science.gov (United States)

    Carrasco-Hernandez, Roberto; Smedley, Andrew R. D.; Webb, Ann R.

    2016-05-01

    Two radiative transfer models are presented that simplify calculations of street canyon spectral irradiances with minimum data input requirements, allowing better assessment of urban exposures than can be provided by standard unobstructed radiation measurements alone. Fast calculations improve the computational performance of radiation models, when numerous repetitions are required in time and location. The core of the models is the calculation of the spectral diffuse-to-global ratios (DGR) from an unobstructed global spectral measurement. The models are based on, and have been tested against, outcomes of the SMARTS2 algorithm (i.e. Simple Model of the Atmospheric Radiative Transfer of Sunshine). The modelled DGRs can then be used to partition global spectral irradiance values into their direct and diffuse components for different solar zenith angles. Finally, the effects of canyon obstructions can be evaluated independently on the direct and diffuse components, which are then recombined to give the total canyon irradiance. The first model allows ozone and aerosol inputs, while the second provides a further simplification, restricted to average ozone and aerosol contents but specifically designed for faster calculations. To assess the effect of obstructions and validate the calculations, a set of experiments with simulated obstructions (simulated canyons) were performed. The greatest source of uncertainty in the simplified calculations is in the treatment of diffuse radiation. The measurement-model agreement is therefore dependent on the region of the sky obscured and ranges from <5 % at all wavelengths to 20-40 % (wavelength dependent) when diffuse sky only is visible from the canyon.

  14. Currents, temperature, attenuation, and conductivity data collected during the Monterey Canyon Experiment from moorings deployed from platforms ROBERT GORDON SPROUL and NOAA Ship McARTHUR from 1993-08-03 to 1995-05-15 (NCEI Accession 0067570)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Monterey Canyon experiment studied the mechanisms that govern the circulation within and the transport of sediment and water through Monterey Submarine Canyon....

  15. Radionuclide concentrations in pinto beans, sweet corn, and zucchini squash grown in Los Alamos Canyon at Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Fresquez, P.R.; Mullen, M.A.; Naranjo, L. Jr.; Armstrong, D.R.

    1997-05-01

    Pinto beans, sweet corn, and zucchini squash (Cucurbita pepo var. black beauty) were grown in a randomized complete-block field/pot experiment at a site that contained the highest observed levels of surface gross gamma radioactivity within Los Alamos Canyon (LAC) at Los Alamos National Laboratory. Soils as well as washed edible and nonedible crop tissues were analyzed for various radionuclides and heavy metals . Most radionuclides, with the exception of {sup 3}H and {sup tot}U, in soil from LAC were detected in significantly higher concentrations (p <0.01) than in soil collected from regional background (RBG) locations. Similarly, most radionuclides in edible crop portions of beans, squash, and corn were detected in significantly higher (p <0.01 and 0.05) concentrations than RBG. Most soil-to-plant concentration ratios for radionuclides in edible and nonedible crop tissues from LAC were within the default values given by the Nuclear Regulatory Commission and Environmental Protection Agency. All heavy metals in soils, as well as edible and nonedible crop tissues grown in soils from LAC, were within RBG concentrations. Overall, the total maximum net positive committed effective dose equivalent (CEDE)--the CEDE plus two sigma for each radioisotope minus background and then all positive doses summed--to a hypothetical 50-year resident that ingested 160 kg of beans, corn, and squash in equal proportions, was 74 mrem y{sup -1}. This dose was below the International Commission on Radiological Protection permissible dose limit (PDL) of 100 mrem y{sup -1} from all pathways; however, the addition of other internal and external exposure route factors may increase the overall dose over the PDL. Also, the risk of an excess cancer fatality, based on 74 mrem y{sup -1}, was 3.7 x 10{sup -5} (37 in a million), which is above the Environmental Protection Agency`s (acceptable) guideline of one in a million. 31 refs., 15 tabs.

  16. Bathymetry Differencing to Quantify Volumetric Change within the Snake River in Hells Canyon

    Science.gov (United States)

    Welcker, C. W.; Hensleigh, J.; Wheaton, J. M.; Anderson, K.; Butler, M.; Hocker, B.

    2013-12-01

    A nearly complete baseline multibeam echosounder (MBES) survey of the 90 km of the Hells Canyon Reach of the Snake River that runs along the border of Idaho and Oregon, US was collected to monitor volumetric change in the sediment resources of this reach (e.g. fall Chinook salmon spawning gravel and beach-building sand). This baseline will be compared to future MBES surveys to determine the impact of the Hells Canyon Complex (HCC) that cuts off the supply of coarse sediment from the relatively small, unimpounded upstream area. MBES surveying is unique from other survey methods (terrestrial LiDAR scanning (TLS)), aerial LiDAR, RTK-GPS, or photogrammetry) in ways that lead to unique errors in the point measurements. For example, unlike static TLS acquisition, MBES surveys are performed from a moving platform that relies on GPS positioning, which introduces one of the largest sources of error into the point cloud. Because the GPS antenna is on the Earth's surface, this error is more extreme and more variable than aerial surveys where the sky view is unobstructed. Beyond the GPS positional accuracy, the errors of each MBES survey point are impacted by the geometry of the beam angle and range, which determine the beam footprint. The extremely rugged river bottom in the Hells Canyon Reach magnifies the error of the points when they are interpolated into a surface for differencing. The methods presented here account for both error sources in the surface (point and interpolation) in order to accurately determine the volumetric change between surveys.

  17. Abiotic & biotic responses of the Colorado River to controlled floods at Glen Canyon Dam, Arizona, USA

    Science.gov (United States)

    Korman, Josh; Melis, Ted; Kennedy, Theodore A.

    2012-01-01

    Closure of Glen Canyon Dam reduced sand supply to the Colorado River in Grand Canyon National Park by about 94% while its operation has also eroded the park's sandbar habitats. Three controlled floods released from the dam since 1995 suggest that sandbars might be rebuilt and maintained, but only if repeated floods are timed to follow tributary sand deliveries below the dam. Monitoring data show that sandbars are dynamic and that their erosion after bar building is positively related with mean daily discharge and negatively related with tributary sand production after controlled floods. The March 2008 flood affected non-native rainbow trout abundance in the Lees Ferry tailwater, which supports a blue ribbon fishery. Downstream trout dispersal from the tailwater results in negative competitive interactions and predation on endangered humpback chub. Early survival rates of age-0 trout increased more than fourfold following the 2008 flood, and twofold in 2009, relative to prior years (2006-2007). Hatch-date analysis indicated that early survival rates were much higher for cohorts that emerged about 2 months after the 2008 flood relative to cohorts that emerged earlier that year. The 2009 survival data suggest that tailwater habitat improvements persisted for at least a year, but apparently decreased in 2010. Increased early survival rates for trout coincided with the increased availability of higher quality drifting food items after the 2008 flood owing to an increase in midges and black flies, preferred food items of rainbow trout. Repeated floods from the dam might sustainably rebuild and maintain sandbars if released when new tributary sand is available below the tailwater. Spring flooding might also sustain increased trout abundance and benefit the tailwater fishery, but also be a potential risk to humpback chub in Grand Canyon.

  18. Packrat middens from Canyon de Chelly, northeastern Arizona: Paleoecological and archaeological implications

    Science.gov (United States)

    Betancourt, Julio L.; Davis, Owen K.

    1984-01-01

    In western North America, pollen data from highland lakes are often used to reconstruct vegetation on the adjacent lowlands. Plant macrofossils and pollen from packrat middens now provide a means to evaluate such reconstructions. On the basis of pollen diagrams from the Chuska Mountains, H. E. Wright, Jr., A. M. Bent, B. S. Hansen, and L. J. Maher, Jr., ((1973), Geological Society of America Bulletin, 84, 1155-1180) arrived at conservative estimates for late Pleistocene depression of highland conifers. In their interpretation, a proposed slight depression of 500 m for lower tree line precluded expansion of Pinus ponderosa into elevations now in desertscrub. Instead, it was suggested that pinyon pine and Artemisia occupied the lowland plateaus. Packrat midden records on either side of the Chuskas fail to verify this model. Early Holocene middens from Chaco Canyon, New Mexico, and a terminal Pleistocene midden from Canyon de Chelly, Arizona, show that blue spruce, limber pine, Douglas fir, dwarf juniper, and Rocky Mountain juniper expanded at least down to 1770 m elevation Neither Colorado pinyon nor ponderosa pine was found as macrofossils in the middens. Artemisia pollen percentages are high in the terminal Pleistocene midden, as they are in the Chuska Mountain pollen sequence, suggesting regional dominance by sagebrush steppe. Of 38 taxa identified, only 3 are shared by middens dated 11,900 and 3120 yr B.P. from Canyon de Chelly, indicating a nearly complete turnover in the flora between the late Pleistocene and late Holocene. Although corn was previously thought to have been introduced to the Colorado plateaus after 2200 yr B.P., the midden dated 3120 yr B.P. contains pollen of corn and other indicators of incipient agriculture.

  19. Socio-economic impact of Horseshoe Canyon coalbed methane development in Alberta : final report

    International Nuclear Information System (INIS)

    This report summarized the results of a socio-economic benefits analysis of coalbed methane (CBM) and natural gas from coal (NGC) development in the Horseshoe Canyon in Alberta. Economic analysis assumptions for evaluating the economic outcomes of different scenarios of future CBM development in the region were also provided. The data and forecasts were used to evaluate the socio-economic benefits of CBM development through the use of an economic impact assessment model. The study resulted in a revised resource assessment for the Horseshoe Canyon coals of approximately 36 trillion standard cubic feet (Tcf) of gas in place. Nine different development scenarios were run which predicted peak Horseshoe Canyon CBM rates of between 1.4 and 1.9 Bdf/day between 2011 and 2017, with sustained rates of approximately 185 MMcf/day as far into the future as 2050. The analysis indicated that CBM development in the region will result in approximately $9 billion of cumulative investment between 2006 and 2026, resulting in total production revenues of $80 to $106 billion. Between 2006 and 2064, CBM development will contribute between $97 and $123 billion to Alberta's gross domestic product (GDP), and another $7 to $12 billion in GDP outside of Alberta. GDP and other socio-economic impacts were distributed over 19 different economic sectors in the report. Results of the report suggested that over 650,000 man-years of employment, and between $15 to $19 billion in tax and royalty revenues will be created by CBM development in the region. Tax and royalty revenues include provincial, federal, and municipal governments. It was concluded that the development of CBM in Alberta will have a significant and positive impact on the future economy of Alberta and Canada. It was noted that there are non-economic impacts associated with the development, including environmental and sociological impacts, that were not addressed in the study. 4 tabs., 4 figs

  20. Bathymetrical distribution and size structure of cold-water coral populations in the Cap de Creus and Lacaze-Duthiers canyons (northwestern Mediterranean)

    Science.gov (United States)

    Gori, A.; Orejas, C.; Madurell, T.; Bramanti, L.; Martins, M.; Quintanilla, E.; Marti-Puig, P.; Lo Iacono, C.; Puig, P.; Requena, S.; Greenacre, M.; Gili, J. M.

    2013-03-01

    Submarine canyons are known as one of the seafloor morphological features where living cold-water coral (CWC) communities develop in the Mediterranean Sea. We investigated the CWC community of the two westernmost submarine canyons of the Gulf of Lions canyon system: the Cap de Creus Canyon (CCC) and Lacaze-Duthiers Canyon (LDC). Coral associations have been studied through video material recorded by means of a manned submersible and a remotely operated vehicle. Video transects have been conducted and analyzed in order to obtain information on (1) coral bathymetric distribution and density patterns, (2) size structure of coral populations, and (3) coral colony position with respect to the substrate. Madrepora oculata was the most abundant CWC in both canyons, while Lophelia pertusa and Dendrophyllia cornigera mostly occurred as isolated colonies or in small patches. An important exception was detected in a vertical cliff in LDC where a large L. pertusa framework was documented. This is the first record of such an extended L. pertusa framework in the Mediterranean Sea. In both canyons coral populations were dominated by medium and large colonies, but the frequent presence of small-sized colonies also indicate active recruitment. The predominant coral orientation (90° and 135°) is probably driven by the current regime as well as by the sediment load transported by the current flows. In general, no clear differences were observed in the abundance and in the size structure of the CWC populations between CCC and LDC, despite large differences in particulate matter between canyons.

  1. Origin and transport of trace metals deposited in the canyons off Lisboa and adjacent slopes (Portuguese Margin) in the last century

    NARCIS (Netherlands)

    Costa, A.M.; Mil-Homens, M.; Lebreiro, S.M.; Richter, T.O.; de Stigter, H.; Boer, W.; Trancoso, M.A.; Melo, Z.; Mouro, F.; Mateus, M.; Canário, J.; Branco, V.; Caetano, M.

    2011-01-01

    Submarine canyons play an important role in the transfer of contaminated sediments from shelf areas to the deeper ocean. To evaluate the importance of submarine canyons adjacent to the Tagus and Sado estuaries (Portuguese Margin) as sediment pathway major and trace elements, (210)Pb radionuclides, o

  2. Mineral Resources of the Hells Canyon Study Area, Wallowa County, Oregon, and Idaho and Adams Counties, Idaho

    Science.gov (United States)

    Simmons, George C.; Gualtieri, James L.; Close, Terry J.; Federspiel, Francis E.; Leszcykowski, Andrew M.

    2007-01-01

    Field studies supporting the evaluation of the mineral potential of the Hells Canyon study area were carried out by the U.S. Geological Survey and the U.S. Bureau of Mines in 1974-76 and 1979. The study area includes (1) the Hells Canyon Wilderness; (2) parts of the Snake River, Rapid River, and West Fork Rapid River Wild and Scenic Rivers; (3) lands included in the second Roadless Area Review and Evaluation (RARE II); and (4) part of the Hells Canyon National Recreation Area. The survey is one of a series of studies to appraise the suitability of the area for inclusion in the National Wilderness Preservation System as required by the Wilderness Act of 1964. The spectacular and mineralized area covers nearly 950 mi2 (2,460 km2) in northeast Oregon and west-central Idaho at the junction of the Northern Rocky Mountains and the Columbia Plateau.

  3. A Transformative Undergraduate Field Trip to the Grand Canyon and Death Valley

    Science.gov (United States)

    Smith, J. A.

    2014-12-01

    Seeing the iconic Grand Canyon and Death Valley in person is a transformative experience for most geologists, including nine undergraduate geology students from upstate New York. The students were enrolled in a one-credit course designed around a nine-day spring-break field trip to Grand Canyon National Park (GCNP) and Death Valley National Park (DVNP). We met once a week before the trip to plan day-to-day activities and discuss background geologic information. Students selected a research topic related to our itinerary and wrote a guidebook entry for the topic. Students' entries were combined with papers, maps, and background material to make a guidebook. The printed guidebooks provided students with a "publication" of their work to show to others and refer to in the field. The nine-day field trip started with a flight into Las Vegas, NV, on 3/1/14. We spent three nights camping at the South Rim of the Grand Canyon, one night camping in Valley of Fire State Park (VOFSP, 55 mi N of Las Vegas), and three nights staying at the Shoshone Education and Research Center (SHEAR) east of Death Valley. Highlights of the trip included the hike along the Bright Angel Trail (and fault) to Plateau Point and recognition of the Great Unconformity at GCNP; the White Domes loop hike, camping at the Beehives, and observation of the Muddy Mountain Overthrust in VOFSP; and hikes at Ubehebe Crater, Badwater Salt Flat, and Natural Bridge Canyon in DVNP. Each student presented his/her research topic at a pertinent point in the field trip; students were impressively well-prepared. One requirement of the course was a poster presentation on each student's research topic at our Undergraduate Research Symposium in April. For most of the students, the poster session was the first experience preparing and presenting a poster. In addition, the class gave a joint colloquium presentation to several hundred science majors and a number of science faculty at Saint Rose. Each student spoke for five

  4. Peaks, plateaus, canyons, and craters: The complex geometry of simple mid-domain effect models

    DEFF Research Database (Denmark)

    Colwell, Robert K.; Gotelli, Nicholas J.; Rahbek, Carsten;

    2009-01-01

    . With large range sizes, the peaks or rings fuse to form a central plateau (one-dimensional) or a flat-topped mound (two-dimensional) of highest species richness. Adding dispersal to the two-dimensional model weakens the peripheral ring and introduces complex patterns for long-distance dispersal. Conclusions...... of a uniform size generate more complex patterns, including peaks, plateaus, canyons, and craters of species richness.......Background: Geographic ranges, randomly located within a bounded geographical domain, Geographic ranges, randomly located within a bounded geographical domain, produce a central hump of species richness (the mid-domain effect, MDE). The hump arises from geometric constraints on the location...

  5. Pelagic underyearling communities in a canyon-shaped reservoir in late summer

    OpenAIRE

    Jiří ŽALOUDÍK; Frouzová, Jaroslava; DRAŠTÍK, Vladislav; Čech, Martin; KRATOCHVÍL, Michal; TUŠER, Michal; JAROLÍM, Oldřich; Říha, Milan; Peterka, Jiří; Prchalová, Marie; Matěna, Josef; Jaromír SEĎA; Kubečka, Jan; Mojmír VAŠEK; Eva HOHAUSOVÁ

    2009-01-01

    The community of pelagic fish fry present during late summer was studied in the canyon-shaped and eutrophic Římov Reservoir, Czech Republic, using nighttime trawling over seven years. Cyprinid fish dominated in the open water area throughout the period investigated. The highest mean density of fry in the surface water layer was observed in 1999 (15 ind 100 m-3), the lowest in 2000 (0.1 ind 100 m-3). A pronounced spatial gradient in the distribution of fry was observed in the reservoir in all ...

  6. Simulation of wind-driven dispersion of fire pollutants in a street canyon using FDS.

    Science.gov (United States)

    Pesic, Dusica J; Blagojevic, Milan Dj; Zivkovic, Nenad V

    2014-01-01

    Air quality in urban areas attracts great attention due to increasing pollutant emissions and their negative effects on human health and environment. Numerous studies, such as those by Mouilleau and Champassith (J Loss Prevent Proc 22(3): 316-323, 2009), Xie et al. (J Hydrodyn 21(1): 108-117, 2009), and Yassin (Environ Sci Pollut Res 20(6): 3975-3988, 2013) focus on the air pollutant dispersion with no buoyancy effect or weak buoyancy effect. A few studies, such as those by Hu et al. (J Hazard Mater 166(1): 394-406, 2009; J Hazard Mater 192(3): 940-948, 2011; J Civ Eng Manag (2013)) focus on the fire-induced dispersion of pollutants with heat buoyancy release rate in the range from 0.5 to 20 MW. However, the air pollution source might very often be concentrated and intensive, as a consequence of the hazardous materials fire. Namely, transportation of fuel through urban areas occurs regularly, because it is often impossible to find alternative supply routes. It is accompanied with the risk of fire accident occurrences. Accident prevention strategies require analysis of the worst scenarios in which fire products jeopardize the exposed population and environment. The aim of this article is to analyze the impact of wind flow on air pollution and human vulnerability to fire products in a street canyon. For simulation of the gasoline tanker truck fire as a result of a multivehicle accident, computational fluid dynamics large eddy simulation method has been used. Numerical results show that the fire products flow vertically upward, without touching the walls of the buildings in the absence of wind. However, when the wind velocity reaches the critical value, the products touch the walls of the buildings on both sides of the street canyon. The concentrations of carbon monoxide and soot decrease, whereas carbon dioxide concentration increases with the rise of height above the street canyon ground level. The longitudinal concentration of the pollutants inside the street

  7. "To Drink from Places": Uncovering a Rich Way of Life Near the Grand Canyon's North Rim

    OpenAIRE

    Rich, Melinda Snow

    2010-01-01

    The chapters of this thesis focus on the history and stories of the people who built and traveled down the highways--Highway 89A, Highway 89, and Highway 67--that branch out from the junction in front of Jacob Lake Inn, the Bowman/Rich family's 87-year-old lodge. The family's role in building roads, supporting and encouraging the growing tourist industry in Kanab and the North Rim of the Grand Canyon, and the converging effects of these choices have created the unique family culture and contr...

  8. Characterizing 6 August 2007 Crandall Canyon mine collapse from ALOS PALSAR InSAR

    Science.gov (United States)

    Lu, Zhong; Wicks, Charles

    2010-01-01

    We used ALOS InSAR images to study land surface deformation over the Crandall Canyon mine in Utah, which collapsed on 6 August 2007 and killed six miners. The collapse was registered as a ML 3.9 seismic event. An InSAR image spanning the time of the collapse shows 25–30 cm surface subsidence over the mine. We used distributed dislocation sources to model the deformation field, and found that a collapse source model alone does not adequately fit the deformation

  9. POPULATION ESTIMATION OF SPERM WHALES (PHYSETER MACROCEPHALUS) FROM BLEIK CANYON, NORWAY

    OpenAIRE

    2011-01-01

    The focus of this thesis is the population of adult male sperm whales in Bleik Canyon off the coast of northern Norway. Previous studies have shown this population to be an open population with a few individuals present for many years and a large group of exchanging males, mainly younger individuals. My study aims to update the current abundance estimate with data from 1987 to 2010, investigate individuals that are long-time present in the area and highlight some of the concern of using both ...

  10. Macro- and megafauna recorded in the submarine Bari Canyon (southern Adriatic, Mediterranean Sea) using different tools

    OpenAIRE

    G. D'ONGHIA; F. Capezzuto; F. CARDONE; Carlucci, R.; Carluccio, A.; G. CHIMIENTI; G. CORRIERO; C. LONGO; Maiorano, P.; F Mastrototaro; P. PANETTA; Rosso, A; R. SANFILIPPO; Sion, L.; A. TURSI

    2015-01-01

    Macro- and megafauna were recorded in the submarine Bari Canyon (southern Adriatic Sea, Mediterranean Sea) during an oceanographic cruise carried out in May-June 2012 and an experimental fishing survey conducted in November 2013. During the former, a total of 20 benthic samples were taken using a Van Veen grab at depths between 268 and 770 m and 4 deployments of a baited lander, for about 43 hours of video records, were carried out at depths between 443 and 788 m. During the latter, 8 longlin...

  11. Modelling segregation effects of heterogeneous emissions on ozone levels in idealised urban street canyons: Using photochemical box models

    International Nuclear Information System (INIS)

    Air quality models include representations of pollutant emissions, which necessarily entail spatial averaging to reflect the model grid size; such averaging may result in significant uncertainties and/or systematic biases in the model output. This study investigates such uncertainties, considering ozone concentrations in idealised street canyons within the urban canopy. A photochemical model with grid-averaged emissions of street canyons is compared with a multiple-box model considering each canyon independently. The results reveal that the averaged, ‘one-box’ model may significantly underestimate true (independent canyon mean) ozone concentrations for typical urban areas, and that the performance of the averaged model is improved for more ‘green’ and/or less trafficked areas. Our findings also suggest that the trends of 2005–2020 in emissions, in isolation, reduce the error inherent in the averaged-emissions treatment. These new findings may be used to evaluate uncertainties in modelled urban ozone concentrations when grid-averaged emissions are adopted. - Highlights: • Grid-based models adopting a grid-averaging scheme of emissions may result in model uncertainties. • Such uncertainties considering ozone levels in idealised street canyons are examined. • The one-box model significantly underestimates the street-level ozone abundance. • The performance of the one-box model is improved for more ‘green’ or less trafficked areas. • Future emission trends are expected to lead to the error in the one-box model approach falling. - A grid-based urban air quality model, if adopting a grid-averaging scheme of emissions from segregated street canyons, may significantly underestimate the street-level ozone abundance

  12. AUV Mapping and ROV Exploration of Los Frailes Submarine Canyon, Cabo Pulmo National Marine Park, Baja California Sur, Mexico

    Science.gov (United States)

    Troni, G.; Caress, D. W.; Graves, D.; Thomas, H. J.; Thompson, D.; Barry, J. P.; Aburto-Oropeza, O.; Johnson, A. F.; Lundsten, L.

    2015-12-01

    Los Frailes submarine canyon is located at the south boundary of the Cabo Pulmo National Marine Park on the southeast tip of the Baja California Peninsula. During the Monterey Bay Aquarium Research Institute (MBARI) 2015 Gulf of California expedition we used an autonomous underwater vehicle (AUV) to map this canyon from 50 m to 450 m depths, and then explored the canyon with a small remotely operated vehicle (ROV). This three day R/V Rachel Carson cruise was a collaboration with the Center for Marine Biodiversity and Conservation at Scripps Institution of Oceanography and the Centro para la Biodiversidad Marina y la Conservación in La Paz. The MBARI AUV D. Allan B. collected high resolution bathymetry, sidescan, and subbottom profiles of Los Frailes submarine canyon and part of the north Cabo Pulmo deep reef. In order to safely generate a 1-m lateral resolution multibeam bathymetry map in the nearshore high relief terrain, the mapping operations consisted of an initial short survey following the 100-m isobath followed by a series of short, incremental AUV missions located on the deep edge of the new AUV bathymetry. The MBARI Mini-ROV was used to explore the submarine canyon within the detailed map created by the MBARI AUV. The Mini-ROV is a 1.2-m-long, 350 kg, 1,500-m-depth-rated ROV designed and constructed by MBARI. It is controlled by six 600-watt thrusters and is equipped with a high-definition video camera and navigation sensors. This small ROV carries less accurate, lower cost navigation sensors than larger vehicles. We implemented new algorithms to localize combining Doppler velocity log sensor data and low-cost MEMS-based inertial sensor data with sporadic ultra-short baseline position measurements to provide a high accuracy position estimation. The navigation performance allowed us to colocate the ROV video imagery with the 1-m resolution bathymetric map of the submarine canyon. Upper Los Frailes Canyon is rugged and, aside from small sand pockets along

  13. Modelling photochemical pollutants in a deep urban street canyon: Application of a coupled two-box model approximation

    Science.gov (United States)

    Zhong, Jian; Cai, Xiao-Ming; Bloss, William James

    2016-10-01

    Air pollution associated with road transport is a major environmental issue in urban areas. Buildings in urban areas are the artificial obstacles to atmospheric flow and cause reduced ventilation for street canyons. For a deep street canyon, there is evidence of the formation of multiple segregated vortices, which generate flow regimes such that pollutants exhibit a significant contrast between these vortices. This results in poor air ventilation conditions at pedestrian level, thereby leading to elevated pollutant levels and potential breaches of air quality limits. The hypothesis of a well-mixed deep street canyon in the practical one-box model approach is shown to be inappropriate. This study implements a simplified simulation of the canyon volume: a coupled two-box model with a reduced chemical scheme to represent the key photochemical processes with timescales similar to and smaller than the turbulent mixing timescale. The two-box model captures the significant pollutant contrast between the lower and upper parts of a deep street canyon, particularly for NO2. Core important parameters (i.e. heterogeneity coefficient, exchange velocity and box height ratio) in the two-box model approach were investigated through sensitivity tests. The two-box model results identify the emission regimes and the meteorological conditions under which NO2 in the lower canyon (i.e. the region of interest for the assessment of human health effects) is in breach of air quality standards. Higher NO2 levels were observed for the cases with higher heterogeneity coefficients (the two boxes are more segregated), with lower exchange velocities (worse ventilation conditions), or with smaller box height ratios (reduced dilution possibly due to secondary smaller eddies in the lower canyon). The performance of a one-box model using the same chemical scheme is also evaluated against the two-box model. The one-box model was found to systematically underestimate NO2 levels compared with those in

  14. WSN system design by using an innovative neural network model to perform thermals forecasting in a urban canyon scenario

    Science.gov (United States)

    Giuseppina, Nicolosi; Salvatore, Tirrito

    2015-12-01

    Wireless Sensor Networks (WSNs) were studied by researchers in order to manage Heating, Ventilating and Air-Conditioning (HVAC) indoor systems. WSN can be useful specially to regulate indoor confort in a urban canyon scenario, where the thermal parameters vary rapidly, influenced by outdoor climate changing. This paper shows an innovative neural network approach, by using WSN data collected, in order to forecast the indoor temperature to varying the outdoor conditions based on climate parameters and boundary conditions typically of urban canyon. In this work more attention will be done to influence of traffic jam and number of vehicles in queue.

  15. The Submarine Paleoseismic Recording Threshold of Shallow Cascadia Earthquakes Under a Wide Variety of Site Conditions

    Science.gov (United States)

    Black, B.; Goldfinger, C.; Patton, J. R.; Morey, A. E.; Galer, S.; Hausmann, R. B.

    2015-12-01

    The triggering, recording, and preservation of seismoturbidites depends on thresholds for each step that involve slope stability, shear strength, sediment supply, bioturbation and other factors. An important factor is the triggering distances for earthquakes of varying magnitudes from a given site. Data from paleoseismic studies globally (Japan, Taiwan, Sumatra, Black Sea, Sea of Marmara, Portugal, Haiti, California Borderlands, Monterey Bay, alpine lakes in Chile, Lake Washington, and southern Cascadia lakes) were compiled as a basis for comparison between sites. A limited assessment of site conditions such as across strike vs. along strike position of core sites, fault type, directivity, and Q value was included. Global averages suggest an MMI of 5.5 and distance of ~ 50-100 km is most common. Maximum triggering distances were estimated as 60-120 km for the CSZ, and 40-75 km for the NSAF based on existing data and comparisons to global values. The region between Eel Canyon and Mendocino Channel (CSZ) and Noyo Canyon (NSAF) has a higher likelihood of recording at least a portion of past seismicity from both the NSAF and CSZ, though Noyo Canyon is likely at the limit of possible influence from the CSZ. The high seismoturbidite frequency (240 yrs. vs. 500 yrs. in Washington) of southern Cascadia (excluding the Eel system) shows clear continuity along strike nearly bed for bed over 170 km (cores, CHIRP profiles), crossing four canyon systems. The record shows a weak relationship to sediment supply from the canyons, and no relationship to slope angle, recently suggested as an explanation. The average axial slope is 3-6 o for these systems, with a few short pitches of 12-20 o. By comparison, the lower frequency record at Hydrate Ridge (~ 350 yrs.) has a steeper average source slope of 10o, steep 20-30 o pitches and no modern sediment supply. The turbidite frequency at the base of the upper reach of Quinault Canyon is lower still (~ 500 years), but the source slope

  16. Vertical stratification in the distribution of demersal fishes along the walls of the La Jolla and Scripps submarine canyons, California, USA

    Science.gov (United States)

    Smith, Joshua G.; Lindholm, James

    2016-08-01

    The geographic distributions of many coastal marine fish assemblages are strongly driven by habitat features, particularly among demersal fishes that live along the seafloor. Ecologists have long recognized the importance of characterizing fish habitat associations, especially where spatial management is under consideration. However, little is known about fish distributions and habitat suitability in unique demersal habitats such as submarine canyons. The active continental margin of the California coast is cut by eight submarine canyons, several of which extend from the shore to the deep abyssal plain. We sampled the demersal fish assemblages in two of those canyons: (1) the Scripps submarine canyon in the San-Diego-Scripps State Marine Conservation Area (SMCA) and (2) the La Jolla canyon in the Matlahuayl State Marine Reserve (SMR) to gain insight into both the distributions and habitat associations of demersal fishes in canyons. A remotely operated vehicle was used to conduct 21 vertically oriented transects along the canyon walls in depths ranging from 20 to 300 m. Species composition was assessed in three depth-stratified zones (100 m per zone) along the canyon walls. Species richness, abundance, and attributes of the surrounding canyon habitat structure (slope and benthic terrain ruggedness) were quantified. Three distinct assemblage groupings were identified, which comprised 35 species of demersal fishes from 17 families. Among all factors analyzed in this study, depth, slope, and ruggedness were strong explanatory variables of patterns of species richness and abundance; however, the relationship between depth and assemblage structure was non-linear. The greatest number of species was observed in the mid depth-stratified zone. These trends suggest that variation in canyon dynamics across depth strata may facilitate distinct assemblage groupings of demersal fishes, which can in turn be used to better manage these unique habitats.

  17. Sequential Quadratic Method for GPS NLOS Positioning in Urban Canyon Envi-ronments

    Directory of Open Access Journals (Sweden)

    He-Sheng Wang

    2013-03-01

    Full Text Available In this paper, the problem of GPS non-line-of-sight (NLOS positioning in urban canyon environment is considered. We propose a new position-determination estimator based on the sequential quadratic programming (SQP that is able to estimate and eliminate the path-delay error caused by the indirect transmission of the GPS signal. The estimator takes into account the measurement bias resulting from NLOS transmission, and in the mean-time also improves the location accuracy of a satellite positioning system. The present method can effectively eliminate the NLOS delay errors and is also able to improve the location accuracy of a satellite navigation receiver in an urban canyon environment. A Wilcoxon-norm-based regressor is further derived to improve the probability of detection of the NLOS biases. The Wilcoxon regressor is a robust estimator that is well suitable for identifying outliers (in our case, the NLOS biases during the regression process. In our experimental results, it is demonstrated that the proposed estimator can compute the coordinate of a user location in an accurate fashion after identifying and removing the measurement biases.

  18. Modeling post-fire hydro-geomorphic recovery in the Waldo Canyon Fire

    Science.gov (United States)

    Kinoshita, Alicia; Nourbakhshbeidokhti, Samira; Chin, Anne

    2016-04-01

    Wildfire can have significant impacts on watershed hydrology and geomorphology by changing soil properties and removing vegetation, often increasing runoff and soil erosion and deposition, debris flows, and flooding. Watershed systems may take several years or longer to recover. During this time, post-fire channel changes have the potential to alter hydraulics that influence characteristics such as time of concentration and increase time to peak flow, flow capacity, and velocity. Using the case of the 2012 Waldo Canyon Fire in Colorado (USA), this research will leverage field-based surveys and terrestrial Light Detection and Ranging (LiDAR) data to parameterize KINEROS2 (KINematic runoff and EROSion), an event oriented, physically-based watershed runoff and erosion model. We will use the Automated Geospatial Watershed Assessment (AGWA) tool, which is a GIS-based hydrologic modeling tool that uses commonly available GIS data layers to parameterize, execute, and spatially visualize runoff and sediment yield for watersheds impacted by the Waldo Canyon Fire. Specifically, two models are developed, an unburned (Bear Creek) and burned (Williams) watershed. The models will simulate burn severity and treatment conditions. Field data will be used to validate the burned watersheds for pre- and post-fire changes in infiltration, runoff, peak flow, sediment yield, and sediment discharge. Spatial modeling will provide insight into post-fire patterns for varying treatment, burn severity, and climate scenarios. Results will also provide post-fire managers with improved hydro-geomorphic modeling and prediction tools for water resources management and mitigation efforts.

  19. Scorpion biodiversity and interslope divergence at "evolution canyon", lower Nahal Oren microsite, Mt. Carmel, Israel.

    Directory of Open Access Journals (Sweden)

    Shmuel Raz

    Full Text Available BACKGROUND: Local natural laboratories, designated by us as the "Evolution Canyon" model, are excellent tools to study regional and global ecological dynamics across life. They present abiotic and biotic contrasts locally, permitting the pursuit of observations and experiments across diverse taxa sharing sharp microecological subdivisions. Higher solar radiation received by the "African savannah-like" south-facing slopes (AS in canyons north of the equator than by the opposite "European maquis-like" north-facing slopes (ES is associated with higher abiotic stress. Scorpions are a suitable taxon to study interslope biodiversity differences, associated with the differences in abiotic factors (climate, drought, due to their ability to adapt to dry environments. METHODOLOGY/PRINCIPAL FINDINGS: Scorpions were studied by the turning stone method and by UV light methods. The pattern observed in scorpions was contrasted with similar patterns in several other taxa at the same place. As expected, the AS proved to be significantly more speciose regarding scorpions, paralleling the interslope patterns in taxa such as lizards and snakes, butterflies (Rhopalocera, beetles (families Tenebrionidae, Dermestidae, Chrysomelidae, and grasshoppers (Orthoptera. CONCLUSIONS/SIGNIFICANCE: Our results support an earlier conclusion stating that the homogenizing effects of migration and stochasticity are not able to eliminate the interslope intra- and interspecific differences in biodiversity despite an interslope distance of only 100 m at the "EC" valley bottom. In our opinion, the interslope microclimate selection, driven mainly by differences in insolance, could be the primary factor responsible for the observed interslope pattern.

  20. Pumping test results for wells within Potrero Canyon, Morongo Band of Mission Indians Reservation, California

    Science.gov (United States)

    Pimentel, M. Isabel; Christensen, Allen H.

    2003-01-01

    Wells in Potrero Canyon are the main source of water for the Morongo Band of Mission Indians, located near Banning, California. A series of pumping tests were completed on four water-supply wells in the Canyon during February 27 to March 2, 2001. The purpose of the tests was to determine the productivity of each well and the interference (drawdown or water-level decline) each pumped well produced in surrounding wells. During each pumping test, a well was pumped at a fairly constant rate for several hours and drawdown was measured in the pumping well; nearby production wells (mostly idle) were used as observation wells. Productivity of the pumping well, specific capacity in gallons per minute per foot of drawdown (gal/min/ft), was determined from time-drawdown data in the pumping well. The range of specific capacities from these tests were 29.9 gal/min/ft, measured in well 24P3 (2S/1E-24P3) to 12.8 gal/min/ft in well 25H1. A specific capacity of 34.4 gal/min/ft was reported (Constant Flow Test notes by McCalla Bros.) for well 24N1. The amount of the drawdown in the observation wells during each pumping test was used to determine the interference between wells.

  1. Analysis of thermal field within an urban canyon with variable thermophysical characteristics of the building's walls

    Science.gov (United States)

    De Lieto Vollaro, A.; Galli, G.; Vallati, A.; Romagnoli, R.

    2015-11-01

    In a typical urban configuration, a microclimatic analysis has been carried out. Using a CFD method, a N-S oriented urban street canyon, with a given H/W ratio, has been examined. The standard k-ε turbulence model has been used to simulate a three-dimensional flow field and to calculate the thermo-fluid dynamics parameters that characterize the street canyon. In this study has been analyzed the thermal flow field when the walls of the building change the properties of solar radiation absorption, in particular for α=0.2 and α=0.8. Solar radiation considered is that of 21/07 in Milan in two different hours: at 11:00 a.m. and at 02:00 p.m. The study shows the importance of the thermophysical properties of a wall, in the development of the thermal field and flow field. This is a very important topic, in terms of improvement of wellbeing and the quality of the air within the cities, through the choice of materials and colors of the facades of buildings.

  2. The summer assemblage of large pelagic Crustacea in the Gully submarine canyon: Major patterns

    Science.gov (United States)

    MacIsaac, K. G.; Kenchington, T. J.; Kenchington, E. L. R.; Best, M.

    2014-06-01

    We describe the trawl-vulnerable crustacean micronekton and macrozooplankton of the Gully, a large, shelf-incising submarine canyon off Nova Scotia, Canada, and a Marine Protected Area. Over 68 species of pelagic crustacea were collected with an International Young Gadoid Pelagic Trawl during three annual summer surveys at one fixed station in the canyon. Depths sampled ranged from the surface to the upper bathypelagic zone, concentrated in the upper 1250 m, with a maximum depth of 1500 m. The crustacean fauna was dominated by cold temperate species typical of mid- to higher-latitudes in the North Atlantic. Meganyctiphanes norvegica and Eusergestes arcticus were particularly dominant in terms of both observed biomass and abundance above 750 m depth. At least 17 species were new records for Canadian waters. The species assemblage of the station varied primarily with depth and diel cycle, the only dominant members of the assemblage showing pronounced inter-annual variations in catch being M. norvegica and Themisto gaudichaudii, both relatively shallow living species.

  3. Measurements and modeling pollution from traffic in a street canyon: Assessing and ranking the influences

    Directory of Open Access Journals (Sweden)

    Milosavljević Branimir Lj.

    2015-01-01

    Full Text Available More than half a century, the scientific community is trying to understand the mechanisms and conditions of pollution dispersion within urban areas. Thereat, special attention has been focused on specific areas, such as a street canyon, in which harmful concentrations higher than allowed are more likely registered. However, there is still a controversy about the conditions of occurrence and impact of the individual air pollution components due to fluctuations of key contributions. Given that OSPM model is a well-known semi-empirical model specializing in the assessment of air quality within a street canyon, after its testing and validation, the results of subsequent simulations were used as a basis for planning a special experiment in order to implement 48 full factorial designs, where using the response surface methodology, as the final objective, an answer was precisely given on the impact and contribution of urban air pollution components. In addition to the main objective of this study, as a secondary, but not less important result defining emission factors for CO and NOx can be emphasized, which to date have not been determined for the fleet of the Republic of Serbia. [Projekat Ministarstva nauke Republike Srbije, br. TR 35041

  4. Late Quaternary vegetation and climate history of a perennial river canyon in the Rīo Salado basin (22°S) of Northern Chile

    Science.gov (United States)

    Latorre, Claudio; Betancourt, Julio L.; Arroyo, Mary T.K.

    2006-01-01

    Plant macrofossils from 33 rodent middens sampled at three sites between 2910 and 3150 m elevation in the main canyon of the Rīo Salado, northern Chile, yield a unique record of vegetation and climate over the past 22,000 cal yr BP. Presence of low-elevation Prepuna taxa throughout the record suggests that mean annual temperature never cooled by more than 5°C and may have been near-modern at 16,270 cal yr BP. Displacements in the lower limits of Andean steppe and Puna taxa indicate that mean annual rainfall was twice modern at 17,520-16,270 cal yr BP. This pluvial event coincides with infilling of paleolake Tauca on the Bolivian Altiplano, increased ENSO activity inferred from a marine core near Lima, abrupt deglaciation in southern Chile, and Heinrich Event 1. Moderate to large increases in precipitation also occurred at 11,770-9550 (Central Atacama Pluvial Event), 7330-6720, 3490-2320 and at 800 cal yr BP. Desiccation occurred at 14,180, 8910-8640, and 4865 cal yr BP. Compared to other midden sites in the region, early Holocene desiccation seems to have happened progressively earlier farther south. Emerging trends from the cumulative midden record in the central Atacama agree at millennial timescales with improved paleolake chronologies for the Bolivian Altiplano, implying common forcing through changes in equatorial Pacific sea-surface temperature gradients.

  5. Floodplain statement of findings for corrective actions in Potrillo Canyon technical area-36, Los Alamos National Laboratory, Los Alamos, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Keller, David Charles [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-05-18

    In 2014, baseline storm water monitoring samples for Potrillo Canyon Sample Management Area at Los Alamos National Laboratory (LANL) exceeded the National Pollutant Discharge Elimination System Individual Permit No. NM0030759 target action level (TAL) of 15 picocuries per liter (pCi/L) for gross-alpha radioactivity (393 pCi/L) and a TAL of 30 pCi/L for radium-226 and radium-228 (95.9 pCi/L). Consequently, erosion control measures within the management area are proposed to minimize sediment migration, a corrective action under the permit that is a requirement of the New Mexico Environment Department consent decree and a good management practice to limit off-site sediment migration. The area proposed for erosion controls consists of portions of Technical Area 36 that were used as firing sites primarily involving high explosives (HE) and metal (e.g., depleted uranium, lead, copper, aluminum, and steel), small-explosives experiments and burn pits (burn pits were used for burning and disposal of test debris). In addition, underground explosive tests at an approximate depth of 100 feet were also conducted. These watershed-based storm water controls will focus on addressing erosion occurring within the floodplain through mitigating and reducing both current and future channelization and head cutting.

  6. Floodplain statement of findings for corrective actions in Potrillo Canyon technical area-36, Los Alamos National Laboratory, Los Alamos, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Keller, David Charles [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-05-18

    In 2014, baseline storm water monitoring samples for Potrillo Canyon Sample Management Area (Figure 1) at Los Alamos National Laboratory (LANL) exceeded the National Pollutant Discharge Elimination System Individual Permit No. NM0030759 target action level (TAL) of 15 picocuries per liter (pCi/L) for gross-alpha radioactivity (393 pCi/L) and a TAL of 30 pCi/L for radium-226 and radium-228 (95.9 pCi/L). Consequently, erosion control measures within the management area are proposed to minimize sediment migration, a corrective action under the permit that is a requirement of the New Mexico Environment Department consent decree and a good management practice to limit off site sediment migration. The area proposed for erosion controls (Figure 1) consists of portions of Technical Area 36 that were used as firing sites primarily involved high explosives (HE) and metal (e.g., depleted uranium, lead, copper, aluminum, and steel), small-explosives experiments and burn pits (burn pits were used for burning and disposal of test debris). In addition, underground explosive tests were conducted at an approximate depth of 100 feet were also conducted. These watershed-based storm water controls will focus on addressing erosion occurring within the floodplain through mitigating and reducing both current and future channelization and head cutting.

  7. A natural resource condition assessment for Sequoia and Kings Canyon National Parks: Appendix 22: climatic change

    Science.gov (United States)

    Das, Adrian J.; Stephenson, Nathan L.

    2013-01-01

    Climate is a master controller of the structure, composition, and function of biotic communities, affecting them both directly, through physiological effects, and indirectly, by mediating biotic interactions and by influencing disturbance regimes. Sequoia and Kings Canyon National Park’s (SEKI’s) dramatic elevational changes in biotic communities -- from warm mediterranean to cold alpine -- are but one manifestation of climate’s overarching importance in shaping SEKI’s landscape. Yet humans are now altering the global climate, with measurable effects on ecosystems (IPCC 2007). Over the last few decades across the western United States, human-induced climatic changes have likely contributed to observed declines in fraction of precipitation falling as snow and snowpack water content (Mote et al. 2005, Knowles et al. 2006), advance in spring snowmelt (Stewart et al. 2005, Barnett et al. 2008), and consequent increase in area burned in wildfires (Westerling et al. 2006). In the Sierra Nevada, warming temperatures have likely contributed to observed glacial recession (Basagic 2008), uphill migration of small mammals (Moritz et al. 2008), and increasing tree mortality rates (van Mantgem and Stephenson 2007, van Mantgem et al. 2009). More substantial changes can be expected for the future (e.g., IPCC 2007). Given the central importance of climate and climatic changes, we sought to describe long-term trends in temperature and precipitation at SEKI. Time and budget constraints limited us to analyses of mean annual temperature and mean annual precipitation, using readily-available data. If funds become available in the future, further analyses will be needed to analyze trends by season, trends in daily minimum and maximum temperatures, and so on. We chose to analyze data from individual weather stations rather than use interpolated climatic data from sources such as PRISM (http://www.prism.oregonstate.edu/). In topographically complex mountainous regions with few

  8. Formerly utilized MED/AEC sites remedial action program. Final report

    International Nuclear Information System (INIS)

    Current radiological conditions were evaluated for the site of a former radioactive liquid waste treatment plant and the interconnected canyons that received both treated and untreated effluents between 1944 and 1951. The liquid radioactive wastes were generated by research with nuclear materials at Los Alamos, New Mexico, for the World War II Manhattan Engineer District atomic bomb project and subsequently by work conducted for the Atomic Energy Commission. After decommissioning of the treatment plant and decontamination of the site and part of one canyon, ownership of some of the land in question was transferred to Los Alamos County by the Federal Government in 1967. Some residual radioactivity attributable to the effluents remained and is found on soils and sediments at the former plant site and in the channels of the canyons. The study considered all relevant information including historical records, environmental data extending back to the 1940s, and new data acquired by special field sampling and measurements. Potential exposures to radiation were evaluated for conditions of current and possible future land uses. Maximum estimated doses were about 12% of radiation protection standards, and most were less than 2%. 18 figures, 120 tables

  9. Short-Term Effects of the 2008 High-Flow Experiment on Macroinvertebrates in Colorado River Below Glen Canyon Dam, Arizona

    Science.gov (United States)

    Rosi-Marshall, Emma J.; Kennedy, Theodore A.; Kincaid, Dustin W.; Cross, Wyatt F.; Kelly, Holly A.W.; Behn, Kathrine A.; White, Tyler; Hall, Robert O.; Baxter, Colden V.

    2010-01-01

    Glen Canyon Dam has dramatically altered the physical environment (especially discharge regime, water temperatures, and sediment inputs) of the Colorado River. High-flow experiments (HFE) that mimic one aspect of the natural hydrograph (floods) were implemented in 1996, 2004, and 2008. The primary goal of these experiments was to increase the size and total area of sandbar habitats that provide both camping sites for recreational users and create backwaters (areas of stagnant flow in the lee of return-current eddies) that may be important as rearing habitat for native fish. Experimental flows might also positively or negatively alter the rainbow trout (Oncorhynchus mykiss) sport fishery in the clear tailwater reach below Glen Canyon Dam, Ariz., and native fish populations in downstream reaches (for example, endangered humpback chub, Gila cypha) through changes in available food resources. We examined the short-term response of benthic macroinvertebrates to the March 2008 HFE at three sites [river mile 0 (RM 0, 15.7 miles downriver from the dam), RM 62, and RM 225] along the Colorado River downstream from Glen Canyon Dam by sampling immediately before and then 1, 7, 14, and 30 days after the HFE. We selected these sites because of their importance to management; RM 0 has a valuable trout fishery, and RM 62 is the location of the largest population of the endangered humpback chub in the Grand Canyon. In addition to the short-term collection of samples, as part of parallel investigations, we collected 3 years of monthly (quarterly for RM 62) benthic macroinvertebrate samples that included 15 months of post-HFE data for all three sites, but processing of the samples is only complete for one site (RM 0). At RM 0, the HFE caused an immediate 1.75 g AFDM/m2 (expressed as grams ash-free dry mass, or AFDM) reduction of macroinvertebrate biomass that was driven by significant reductions in the biomass of the two dominant taxa in this reach-Potamopyrgus antipodarum (New

  10. Biostratigraphy and structure of paleozoic host rocks and their relationship to Carlin-type gold deposits in the Jerritt Canyon mining district, Nevada

    Science.gov (United States)

    Peters, S.G.; Armstrong, A.K.; Harris, A.G.; Oscarson, R.L.; Noble, P.J.

    2003-01-01

    The Jerritt Canyon mining district in the northern Independence Range, northern Nevada, contains multiple, nearly horizontal, thrust masses of platform carbonate rocks that are exposed in a series of north- to northeast-elongated, tectonic windows through rocks of the Roberts Mountains allochthon. The Roberts Mountains allochthon was emplaced during the Late Devonian to Early Mississippian Antler orogeny. These thrust masses contain structurally and stratigraphically controlled Carlin-type gold deposits. The gold deposits are hosted in tectonically truncated units of the Silurian to Devonian Hanson Creek and Roberts Mountains Formations that lie within structural slices of an Eastern assemblage of Cambrian to Devonian carbonate rocks. In addition, these multiply thrust-faulted and folded host rocks are structurally interleaved with Mississippian siliciclastic rocks and are overlain structurally by Cambrian to Devonian siliciclastic units of the Roberts Mountains allochthon. All sedimentary rocks were involved in thrusting, high-angle faulting, and folding, and some of these events indicate substantial late Paleozoic and/or Mesozoic regional shortening. Early Pennsylvanian and late Eocene dikes also intrude the sedimentary rocks. These rocks all were uplifted into a northeast-trending range by subsequent late Cenozoic Basin and Range faulting. Eocene sedimentary and volcanic rocks flank part of the range. Pathways of hydrothermal fluid flow and locations of Carlin-type gold orebodies in the Jerritt Canyon mining district were controlled by structural and host-rock geometries within specific lithologies of the stacked thrust masses of Eastern assemblage rocks. The gold deposits are most common proximal to intersections of northeast-striking faults, northwest-striking dikes, and thrust planes that lie adjacent to permeable stratigraphic horizons. The host stratigraphic units include carbonate sequences that contained primary intercrystalline permeability, which

  11. HYDRATE RESEARCH ACTIVITIES THAT BOTH SUPPORT AND DERIVE FROM THE MONITORING STATION/SEA-FLOOR OBSERVATORY, MISSISSIPPI CANYON 118, NORTHERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Lutken, Carol

    2013-07-31

    A permanent observatory has been installed on the seafloor at Federal Lease Block, Mississippi Canyon 118 (MC118), northern Gulf of Mexico. Researched and designed by the Gulf of Mexico Hydrates Research Consortium (GOM-HRC) with the geological, geophysical, geochemical and biological characterization of in situ gas hydrates systems as the research goal, the site has been designated by the Bureau of Ocean Energy Management as a permanent Research Reserve where studies of hydrates and related ocean systems may take place continuously and cooperatively into the foreseeable future. The predominant seafloor feature at MC118 is a carbonate-hydrate complex, officially named Woolsey Mound for the founder of both the GOM-HRC and the concept of the permanent seafloor hydrates research facility, the late James Robert “Bob” Woolsey. As primary investigator of the overall project until his death in mid-2008, Woolsey provided key scientific input and served as chief administrator for the Monitoring Station/ Seafloor Observatory (MS-SFO). This final technical report presents highlights of research and accomplishments to date. Although not all projects reached the status originally envisioned, they are all either complete or positioned for completion at the earliest opportunity. All Department of Energy funds have been exhausted in this effort but, in addition, leveraged to great advantage with additional federal input to the project and matched efforts and resources. This report contains final reports on all subcontracts issued by the University of Mississippi, Administrators of the project, Hydrate research activities that both support and derive from the monitoring station/sea-floor Observatory, Mississippi Canyon 118, northern Gulf of Mexico, as well as status reports on the major components of the project. All subcontractors have fulfilled their primary obligations. Without continued funds designated for further project development, the Monitoring Station

  12. Advantages of Computer Simulation in Enhancing Students' Learning about Landform Evolution: A Case Study Using the Grand Canyon

    Science.gov (United States)

    Luo, Wei; Pelletier, Jon; Duffin, Kirk; Ormand, Carol; Hung, Wei-chen; Shernoff, David J.; Zhai, Xiaoming; Iverson, Ellen; Whalley, Kyle; Gallaher, Courtney; Furness, Walter

    2016-01-01

    The long geological time needed for landform development and evolution poses a challenge for understanding and appreciating the processes involved. The Web-based Interactive Landform Simulation Model--Grand Canyon (WILSIM-GC, http://serc.carleton.edu/landform/) is an educational tool designed to help students better understand such processes,…

  13. 75 FR 19966 - Boulder Canyon Project-Post-2017 Application of the Energy Planning and Management Program Power...

    Science.gov (United States)

    2010-04-16

    ... comment period regarding the application of the Energy Planning and Management Program (Program) Power... Western Area Power Administration Boulder Canyon Project--Post-2017 Application of the Energy Planning and Management Program Power Marketing Initiative AGENCY: Western Area Power Administration, DOE. ACTION:...

  14. 75 FR 75704 - Pacific Gas and Electric Company (Diablo Canyon Nuclear Power Plant, Units 1 And 2); Notice of...

    Science.gov (United States)

    2010-12-06

    ... From the Federal Register Online via the Government Publishing Office ] NUCLEAR REGULATORY COMMISSION Pacific Gas and Electric Company (Diablo Canyon Nuclear Power Plant, Units 1 And 2); Notice of Appointment of Adjudicatory Employee Commissioners: Gregory B. Jaczko, Chairman; Kristine L. Svinicki;...

  15. 77 FR 67391 - Notice of Proposed Supplementary Rules on Public Land in Water Canyon, Humboldt County, NV

    Science.gov (United States)

    2012-11-09

    ... of motor vehicles, to protect public safety and resources on public land within the Water Canyon Recreation Area. These proposed supplementary rules would include limitations and restrictions included..., and trails. The Zone 2 upland area of approximately 2,579 acres is managed under an emphasis for...

  16. Performance assessment of Large Eddy Simulation (LES) for modeling dispersion in an urban street canyon with tree planting

    Science.gov (United States)

    Moonen, P.; Gromke, C.; Dorer, V.

    2013-08-01

    The potential of a Large Eddy Simulation (LES) model to reliably predict near-field pollutant dispersion is assessed. To that extent, detailed time-resolved numerical simulations of coupled flow and dispersion are conducted for a street canyon with tree planting. Different crown porosities are considered. The model performance is assessed in several steps, ranging from a qualitative comparison to measured concentrations, over statistical data analysis by means of scatter plots and box plots, up to the calculation of objective validation metrics. The extensive validation effort highlights and quantifies notable features and shortcomings of the model, which would otherwise remain unnoticed. The model performance is found to be spatially non-uniform. Closer agreement with measurement data is achieved near the canyon ends than for the central part of the canyon, and typical model acceptance criteria are satisfied more easily for the leeward than for the windward canyon wall. This demonstrates the need for rigorous model evaluation. Only quality-assured models can be used with confidence to support assessment, planning and implementation of pollutant mitigation strategies.

  17. 75 FR 1052 - Terra-Gen Dixie Valley, LLC; TGP Dixie Development Company, LLC; New York Canyon, LLC; Notice of...

    Science.gov (United States)

    2010-01-08

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Terra-Gen Dixie Valley, LLC; TGP Dixie Development Company, LLC; New York Canyon, LLC; Notice of Filing December 30, 2009. Take notice that on December 24, 2009, Terra-Gen...

  18. Modelling the dispersion and transport of reactive pollutants in a deep urban street canyon: Using large-eddy simulation

    International Nuclear Information System (INIS)

    This study investigates the dispersion and transport of reactive pollutants in a deep urban street canyon with an aspect ratio of 2 under neutral meteorological conditions using large-eddy simulation. The spatial variation of pollutants is significant due to the existence of two unsteady vortices. The deviation of species abundance from chemical equilibrium for the upper vortex is greater than that for the lower vortex. The interplay of dynamics and chemistry is investigated using two metrics: the photostationary state defect, and the inferred ozone production rate. The latter is found to be negative at all locations within the canyon, pointing to a systematic negative offset to ozone production rates inferred by analogous approaches in environments with incomplete mixing of emissions. This study demonstrates an approach to quantify parameters for a simplified two-box model, which could support traffic management and urban planning strategies and personal exposure assessment. - Highlights: • Large-eddy simulation reproduces two unsteady vortices seen in a lab experiment. • Reactive pollutants in an urban street canyon exhibit significant spatial variation. • O3 production rate inferred by the NOx-O3-steady-state-defect approach is discussed. • Ground level sourced pollutants are largely trapped within the lower vortex. • A method of quantifying parameters of a two-box model is developed. - Reactive pollutants in a deep street canyon exhibit significant spatial variation driven by two unsteady vortices. A method of quantifying parameters of a two-box model is developed

  19. Is this bridge safe? Evaluation of Audiovisual Cues for a Walk on a Small Bridge Over a Canyon

    DEFF Research Database (Denmark)

    Sikström, Erik; Nilsson, Niels Chr.; Götzen, Amalia De;

    2016-01-01

    This paper presents two within-subjects studies (n=23) exploring how different combinations of visual and auditory feedback influence perceived realism, virtual self-perception and the experience of safety during walks on a virtual platform suspended over a canyon. In the first study, the frequen...

  20. Mineral resource potential map of the Blanco Mountain and Black Canyon roadless areas, Inyo and Mono counties, California

    Science.gov (United States)

    Diggles, Michael F.; Blakely, Richard J.; Rains, Richard L.; Schmauch, Steven W.

    1983-01-01

    On the basis of geologic, geochemical, and geophysical investigations and a survey of mines and prospects, the mineral resource potential for gold, silver, lead, zinc, tungsten, and barite of the Blanco Mountain and Black Canyon Roadless Areas is judged to be low to moderate, except for one local area that has high potential for gold and tungsten resources.