WorldWideScience

Sample records for san francisquito canyon

  1. Streamflow gains and losses along San Francisquito Creek and characterization of surface-water and ground-water quality, southern San Mateo and northern Santa Clara counties, California, 1996-97

    Science.gov (United States)

    Metzger, Loren F.

    2002-01-01

    San Francisquito Creek is an important source of recharge to the 22-square-mile San Francisquito Creek alluvial fan ground-water subbasin in the southern San Mateo and northern Santa Clara Counties of California. Ground water supplies as much as 20 percent of the water to some area communities. Local residents are concerned that infiltration and consequently ground-water recharge would be reduced if additional flood-control measures are implemented along San Francisquito Creek. To improve the understanding of the surface-water/ground-water interaction between San Francisquito Creek and the San Francisquito Creek alluvial fan, the U.S. Geological Survey (USGS) estimated streamflow gains and losses along San Francisquito Creek and determined the chemical quality and isotopic composition of surface and ground water in the study area.Streamflow was measured at 13 temporary streamflow-measurement stations to determine streamflow gains and losses along a 8.4-mile section of San Francisquito Creek. A series of five seepage runs between April 1996 and May 1997 indicate that losses in San Francisquito Creek were negligible until it crossed the Pulgas Fault at Sand Hill Road. Streamflow losses increased between Sand Hill Road and Middlefield Road where the alluvial deposits are predominantly coarse-grained and the water table is below the bottom of the channel. The greatest streamflow losses were measured along a 1.8-mile section of the creek between the San Mateo Drive bike bridge and Middlefield Road; average losses between San Mateo Drive and Alma Street and from there to Middlefield Road were 3.1 and 2.5 acre-feet per day, respectively.Downstream from Middlefield Road, streamflow gains and losses owing to seepage may be masked by urban runoff, changes in bank storage, and tidal effects from San Francisco Bay. Streamflow gains measured between Middlefield Road and the 1200 block of Woodland Avenue may be attributable to urban runoff and (or) ground-water inflow. Water

  2. 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...

  3. 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 is...

  4. 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.

  5. Baseline Surveys - Tecolote Canyon, San Diego Co. [ds655

    Data.gov (United States)

    California Department of Resources — Various resource projects have been conducted in the City of San Diego's Open Space Parks as part of the implementation of the City's Multiple Species Conservation...

  6. Vegetation Mapping - Tecolote Canyon, San Diego Co. [ds656

    Data.gov (United States)

    California Department of Resources — Vegetation mapping has been conducted at various City of San Diego Park and Recreation Open Space lands in support of natural resource management objectives and the...

  7. Influence of San Gabriel submarine canyon on narrow-shelf sediment dynamics, southern California

    Science.gov (United States)

    Karl, Herman A.

    1980-01-01

    Variations in the concentration of total suspended particulate matter (TSM) collected 1 m above bottom, changes in vertical profiles of light transmission, and substrate textural patterns reveal a corridor for preferential sediment transport on San Pedro continental shelf, California. During the winter, this corridor, designated the preferential transport corridor (PTC), is defined by higher concentrations of TSM relative to the rest of the shelf and extends for 10-15 km from the inner shelf to the head of San Gabriel Submarine Canyon. Vertical profiles of light transmission within the PTC suggest density stratification throughout the water column and apparent mixing in the upper 15-20 m of water column on either side of the PTC. The PTC is not as fully developed during the summer. Excursions in isopleths of substrate textural variables perpendicular to isobaths in the PTC suggest that although the PTC is seasonally episodic, it recurs regularly over a longer period.

  8. Preliminary Report on the White Canyon Area, San Juan County, Utah

    Science.gov (United States)

    Benson, William Edward Barnes; Trites, A.F.; Beroni, E.P.; Feeger, J.A.

    1952-01-01

    The White Canyon area in San Juan County, Utah, contains known deposits of copper-uranium ore and is currently being mapped and studied by the Geological Survey. To date, approximately 75 square miles, or about 20 percent of the area, has been mapped on a scale 1 inch=1 mile. The White Canyon area is underlain by more than 2,000 feet of sedimentary rocks, Carboniferous to Jurassic(?) in age. The area is on the flank of the Elk Ridge anticline, and the strata have a regional dip of 1 deg to 2 deg SW. The Shinarump conglomerate of Late Triassic age is the principal ore-bearing formation. The Shinarump consists of lenticular beds of sandstone, conglomeratic sandstone, clay, and siltstone, and ranges in thickness from a feather edge to as much as 75 feet. Locally the sandstones contain silicified and carbonized wood and fragments of charcoal. These vegetal remains are especially common in channel-fill deposits. Jointing is prominent in the western part of the area, and apparently affects all formations. Adjacent to the joints some of the redbeds in the sequence are bleached. Deposits of copper-uranium minerals have been found in the Moenkopi, Shinarump, and Chinle formations, but the only production of ore has been from the Shinarump conglomerate. The largest concentration of these minerals is in the lower third of the Shinarump, and the deposits seem to be controlled in part by ancient channel fills and in part by fractures. Locally precipitation of the copper and uranium minerals apparently has been aided by charcoal and clays. Visible uranium minerals include both hard and soft pitchblende and secondary hydrosulfates, phosphates, and silicates. In addition, unidentified uranium compounds are present in carbonized wood and charcoal, and in veinlets of hydrocarbons. Base-metal sulfides have been identified in all prospects that extend beyond the oxidized zone. Secondary copper minerals in the oxidized zone include the hydrous sulfates and carbonates, and possibly

  9. Preliminary report on the White Canyon area, San Juan county, Utah

    Science.gov (United States)

    Benson, William E.; Trites, Albert F.; Beroni, Ernest P.; Feeger, John A.

    1952-01-01

    The White Canyon area, in the central part of San Juan County, Utah, consists of approximately two 15-minute quadrangles. Approximately 75 square miles have been mapped by the Geological Survey on a scale of 1 inch equals 1 mile, using a combined aerial photography-plane table method. Structure contours were drawn on top of the Organ Rock member of the Cutler formation. Parts of the Gonway and North Point claims, 1/4 mile east of the Happy Jack mine, were mapped in detail. The principal objectives of the investigations were: (1) to establish ore guides; (2) to select areas favorable for exploration; and (3) to map the general geology and to determine the regional relationships of the uranium deposits. The White Canyon area is comprised of sedimentary rocks of Carboniferous to Jurassic age, more than 2,000 feet thick, having a regional dip of 1° to 2° SW. The nearest igneous rocks are in the Henry Mountains about 7 miles west of the northern part of the area; The Shinarump conglomerate of the late Triassic age, the principal ore horizon in the White Canyon area, consists of lenticular beds of sandstone, conglomeratic sandstone, conglomerate, clay, and siltstone. The Shinarump conglomerate, absent in places, is as much as 75 feet thick. The sandstones locally contain molds of logs and fragments of altered volcanic ash. Some of the logs have been replaced by copper and uranium minerals and iron oxides. The clay and siltstone underlie and are interbedded with the sandstone, and are most common in channels that cut into the underlying Moenkopi formation. The Shinarump conglomerate contains reworked Moenkopi siltstone fragments, clay balls, carbonized wood, and pebbles of quarts, quartzite, and chert. Jointing is prominent in the Western part of the mapped area. The three most prominent joint trends are due east, N. 65°-75° W., and N. 65°-75° E. All joints have vertical dips. The red beds are bleached along some joints, especially those that trend N. 65°-75° W

  10. Marine neotectonic investigation of the San Gregorio Fault Zone on the northern flank of Monterey Canyon, offshore central California

    Science.gov (United States)

    Maier, K. L.; Paull, C. K.; Brothers, D. S.; McGann, M.; Caress, D. W.; Lundsten, E. M.; Anderson, K.; Gwiazda, R.

    2014-12-01

    The San Gregorio Fault Zone (SGFZ) is part of the North American-Pacific plate boundary and is thought to accommodate right-lateral offset up to 10 mm/yr. Because much of the SGFZ in Monterey Bay, central California, lies offshore in steep submarine canyon bathymetry, little is known of its recent activity. We provide initial direct evidence for faulting where the SGFZ has been interpreted based on canyon morphology to cross the northern flank of Monterey Canyon. High-resolution multibeam bathymetry and chirp subbottom profiles were acquired during 13 dives with the Monterey Bay Aquarium Research Institute's (MBARI) Autonomous Underwater Vehicle (AUV) from 2009-2014 on the northern flank of Monterey Canyon, extending from the shelf edge ~15 km offshore Santa Cruz to ~1850 m water depth. Chirp profiles resolve layered sediments up to ~40 m subsurface in this region, and no fault scarps or seafloor lineaments are visible in the 1-m resolution multibeam bathymetry. At least one subsurface fault is identified within the SGFZ by offset reflections across a discrete, nearly vertical fault. However, this fault is only imaged where mass wasting has exhumed older strata to within ~25 m of the seafloor. Numerous slumps scars on the seafloor and packages of chaotic internal reflectivity in chirp profiles suggest that submarine landslide processes dominate the study area. To constrain the age of reflections offset by the fault, MBARI's Remotely Operated Vehicle (ROV) Doc Ricketts, sampled faces of slump scars where the offset reflections crop out using vibracores and horizontal push cores. Radiocarbon dating of foraminifera within these core samples is being used to constrain the last recorded movement on the fault. Application of AUV and ROV methods allows detailed neotectonic investigation of significant offshore structures, like the SGFZ, that contribute to hazard assessment.

  11. 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...

  12. Geology of Bull Canyon quadrangle, Montrose and San Miguel counties, Colorado

    Science.gov (United States)

    Cater, Fred W.

    1953-01-01

    The Bull 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 depots. 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 tones. 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.

  13. Relative abundance and distribution of fishes within an established Area of Critical Environmental Concern, of the Amargosa River Canyon and Willow Creek, Inyo and San Bernardino Counties, California

    Science.gov (United States)

    Scoppettone, G. Gary; Hereford, Mark E.; Rissler, Peter H.; Johnson, Danielle M.; Salgado, Antonio

    2011-01-01

    The Amargosa River Canyon of San Bernardino and Inyo County, California, has been designated by the Bureau of Land Management as an Area of Critical Environmental Concern, due in part to its unique flora and fauna. As a task of the Area of Critical Environmental Concern implementation plan, a survey of native fishes was conducted from June 21 to August 12, 2010. Geographic Information System tools were used to map sampling locations, which were spaced at 50-meter intervals. Global Positioning Systems were used to locate sampling stations, and stations with adequate water for successful trapping were sampled with baited minnow traps. Amargosa River pupfish (Cyprinodon nevadensis amargosae) and speckled dace (Rhinichthys osculus spp.) were widespread throughout Armargosa River Canyon. Throughout the study area 8,558 pupfish were captured at 194 stations; 3,472 speckled dace were captured at 210 stations; 238 red-swamp crayfish (Procambarus clarkia) were captured at 83 stations; and 1,095 western mosquitofish (Gambusia affinus) were captured at 110 stations. Pupfish were most abundant in open water habitat with native riparian vegetation, and they were significantly less abundant where the stream was completely covered by cattails or where saltcedar (Tamarix sp.) dominated the riparian corridor. There was no relationship between stream cover and speckled dace distribution. Non-native western mosquitofish and red-swamp crayfish densities were significantly higher in stream reaches dominated by saltcedar. The continued spread of saltcedar threatens to negatively affect pupfish and potentially reduce speckled dace abundance throughout the Amargosa River Canyon. This study can serve as baseline information for observing native fish populations in the future, as related to potential changes to the Amargosa River Canyon ecosystem.

  14. Timing of large earthquakes during the past 500 years along the Santa Cruz Mountains segment of the San Andreas fault at Mill Canyon, near Watsonville, California

    Science.gov (United States)

    Fumal, Thomas E.

    2012-01-01

    A paleoseismic investigation across the Santa Cruz Mountains section of the San Andreas fault at Mill Canyon indicates that four surface‐rupturing earthquakes have occurred there during the past ~500  years. At this site, right‐lateral fault slip has moved a low shutter ridge across the mouth of the canyon, ponding latest Holocene sediments. These alluvial deposits are deformed along a narrow zone of faulting. There is excellent evidence for a 1906 (M 7.8) and three earlier earthquakes consisting of well‐developed fissures, scarps, and colluvial wedges. Deformation resulting from the earlier earthquakes is comparable to that from 1906, suggesting they also were large‐magnitude events. The earthquake prior to 1906 occurred either about A.D. 1750 (1711–1770) or A.D. 1855 (1789–1904), depending on assumptions incorporated into two alternative OxCal models. If the later age range is correct, then the earthquake may have been a historical early‐to‐mid‐nineteenth‐century earthquake, possibly the A.D. 1838 earthquake. Both models are viable, and there is no way to select one over the other with the available data. Two earlier earthquakes occurred about A.D. 1690 (1660–1720) and A.D. 1522 (1454–1605). Using OxCal, recalculation of the age of the reported penultimate earthquake reported from the Grizzly Flat site, located about 10 km northwest of Mill Canyon, indicates it occurred about A.D. 1105–1545, earlier than any of the past three earthquakes, and possibly correlates to the fourth earthquake at Mill Canyon.

  15. Possible Connections Between the Coronado Bank Fault Zone and the Newport-Inglewood, Rose Canyon, and Palos Verdes Fault Zones Offshore San Diego County, California.

    Science.gov (United States)

    Sliter, R. W.; Ryan, H. F.

    2003-12-01

    High-resolution multichannel seismic-reflection and deep-tow Huntec data collected by the USGS were interpreted to map the Coronado Bank fault zone (CBFZ) offshore San Diego County, California. The CBFZ is comprised of several major strands (eastern, central, western) that change in both orientation and degree of deformation along strike. Between Coronado Bank and San Diego, the CBFZ trends N25W and occupies a narrow 7 km zone. Immediately north of La Jolla submarine canyon (LJSC), the easternmost strand changes orientation to almost due north and appears to be offset in a right-lateral sense across the canyon axis. The strand merges with a prominent fault that follows the base of the continental slope in about 600 m water depth. The central portion of the CBFZ is mapped as a negative flower structure and deforms seafloor sediment as far north as 15 km north of LJSC. Farther north, this structure is buried by more than 400 m of basin sediment. Along the eastern edge of the Coronado Bank, the western portion of the CBFZ is characterized by high angle normal faults that dip to the east. North of the Coronado Bank, the western segment follows the western edge of a basement high; it cuts through horizontal basin reflectors and in places deforms the seafloor. We mapped an additional splay of the CBFZ that trends N40W; it is only observed north and west of LJSC. Although the predominant trend of the CBFZ is about N40W, along strike deviations from this orientation of some of the strands indicate that these strands connect with other offshore fault zones in the area. Based on the limited data available, the trend of the CBFZ south of Coronado Bank suggests that it might connect with the Rose Canyon fault zone (RCFZ) that has been mapped in San Diego Bay. North of Coronado Bank, the CBFZ is a much broader fault zone (about 25 km wide) composed of diverging fault strands. The westernmost strand may merge with the western strand of the Palos Verdes fault zone (PVFZ) south of

  16. 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

  17. The Fish Canyon magma body, San Juan volcanic field, Colorado: Rejuvenation and eruption of an upper-crustal batholith

    Science.gov (United States)

    Bachmann, Olivier; Dungan, M.A.; Lipman, P.W.

    2002-01-01

    More than 5000 km3 of nearly compositionally homogeneous crystalrich dacite (~68 wt % SiO2: ~45% Pl + Kfs + Qtz + Hbl + Bt + Spn + Mag + Ilm + Ap + Zrn + Po) erupted from the Fish Canyon magma body during three phases: (1) the pre-caldera Pagosa Peak Dacite (an unusual poorly fragmented pyroclastic deposit, ~ 200 km3); (2) the syn-collapse Fish Canyon Tuff (one of the largest known ignimbrites, ~ 5000 km3); (3) the post-collapse Nutras Creek Dacite (a volumetrically minor lava). The late evolution of the Fish Canyon magma is characterized by rejuvenation of a near-solidus upper-crustal intrusive body (mainly crystal mush) of batholithic dimensions. The necessary thermal input was supplied by a shallow intrusion of more mafic magma represented at the surface by sparse andesitic enclaves in late-erupted Fish Canyon Tuff and by the post-caldera Huerto Andesite. The solidified margins of this intrusion are represented by holocrystalline xenoliths with Fish Canyon mineralogy and mineral chemistry and widely dispersed partially remelted polymineralic aggregates, but dehydration melting was not an important mechanism in the rejuvenation of the Fish Canyon magma. Underlying mafic magma may have evolved H2O-F-S-Cl-rich fluids that fluxed melting in the overlying crystal mush. Manifestations of the late up-temperature magma evolution are: (1) resorbed quartz, as well as feldspars displaying a wide spectrum of textures indicative of both resorption and growth, including Rapakivi textures and reverse growth zoning (An27-28 to An32-33) at the margins of many plagioclase phenocrysts; (2) high Sr, Ba, and Eu contents in the high-SiO2 rhyolite matrix glass, which are inconsistent with extreme fractional crystallization of feldspar; (3) oscillatory and reverse growth zoning toward the margins of many euhedral hornblende phenocrysts (rimward increases from ~5??5-6 to 7??7-8??5 wt % Al2O3). Homogeneity in magma composition at the chamber-wide scale, contrasting with extreme textural

  18. Telegraph Canyon Creek, City of Chula Vista, San Diego County, California. Detailed Report for Flood Control. Volume 1. Main Report.

    Science.gov (United States)

    1983-07-01

    social , and historical information concerning the Telegraph Canyon area is very limited. For that reason, and because the economy of the study area is...Diego Department of Sanitation and Flood Control by letter dated November 10, 1978 also reaffirmed its support of such solution. Such reaffirmation...marsh and tidal habitats predominate. This area, known as the J Street Marsh, is a valuable and productive habitat that supports many species of

  19. 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

  20. 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

  1. Investigation of late Pleistocene and Holocene activity in the San Gregorio fault zone on the continental slope north of Monterey Canyon, offshore central California

    Science.gov (United States)

    Maier, Katherine L.; Paull, Charles K.; Brothers, Daniel; Caress, David W.; McGann, Mary; Lundsten, Eve M.; Anderson, Krystle; Gwiazda, Roberto

    2017-01-01

    We provide an extensive high‐resolution geophysical, sediment core, and radiocarbon dataset to address late Pleistocene and Holocene fault activity of the San Gregorio fault zone (SGFZ), offshore central California. The SGFZ occurs primarily offshore in the San Andreas fault system and has been accommodating dextral strike‐slip motion between the Pacific and North American plates since the mid‐Miocene. Our study focuses on the SGFZ where it has been mapped through the continental slope north of Monterey Canyon. From 2009 to 2015, the Monterey Bay Aquarium Research Institute collected high‐resolution multibeam bathymetry and chirp sub‐bottom profiles using an autonomous underwater vehicle (AUV). Targeted samples were collected using a remotely operated vehicle (ROV) to provide radiocarbon age constraints. We integrate the high‐resolution geophysical data with radiocarbon dates to reveal Pleistocene seismic horizons vertically offset less than 5 m on nearly vertical faults. These faults are buried by continuous reflections deposited after ∼17.5  ka and likely following erosion during the last sea‐level lowstand ∼21  ka, bracketing the age of faulting to ∼32–21  ka. Clearly faulted horizons are only detected in a small area where mass wasting exhumed older strata to within ∼25  m of the seafloor. The lack of clearly faulted Holocene deposits and possible highly distributed faulting in the study area are consistent with previous interpretations that late Pleistocene and Holocene activity along the SGFZ may decrease to the south. This study illustrates the complexity of the SGFZ, offshore central California, and demonstrates the utility of very high‐resolution data from combined AUV (geophysical)–ROV (seabed sampling) surveys in offshore studies of fault activity.

  2. 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...

  3. A Study of the Effects of Gas Well Compressor Noise on Breeding Bird Populations of the Rattlesnake Canyon Habitat Management Area, San Juan County, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    LaGory, K.E.; Chang, Young-Soo; Chun, K.C.; Reeves, T.; Liebich, R.; Smith, K.

    2001-06-04

    This report, conducted from May through July 2000, addressed the potential effect of compressor noise on breeding birds in gas-production areas administered by the FFO, specifically in the Rattlesnake Canyon Habitat Management Area northeast of Farmington, New Mexico. The study was designed to quantify and characterize noise output from these compressors and to determine if compressor noise affected bird populations in adjacent habitat during the breeding season.

  4. Subinertial canyon resonance

    Science.gov (United States)

    Clarke, Allan J.; Van Gorder, Stephen

    2016-04-01

    Near the bottom of a narrow canyon currents that oscillate back and forth along the bottom slope hx in a stratified ocean of buoyancy frequency N do so with a natural internal gravitational frequency Nhx. From May 2012 to May 2013 Acoustic Doppler Current Profiler measurements were made at 715 m depth in the deep narrow part of the DeSoto Canyon south of Pensacola, Florida, in water with 2π/Nhx ≈ 2.5 days. Above the canyon the flow follows the large-scale isobaths, but beneath the canyon rim the current oscillates along the canyon axis with 2-3 day periodicity, and is much stronger than and uncorrelated with the overlying flow. A simple theoretical model explains the resonant response. Published observations from the Hudson and Gully canyons suggest that the strong subinertial current oscillations observed in these canyons occur close to the relevant local frequency Nhx, consistent with the proposed simple model physics.

  5. 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

  6. 75 FR 18482 - Stanford University Habitat Conservation Plan

    Science.gov (United States)

    2010-04-12

    ... watershed includes San Francisquito, Los Trancos, Corte Madera, Bear, Dennis Martin, Sausal, and Alambique creeks, and portions of San Francisquito, Los Trancos, Corte Madera, and Bear creeks flow through...

  7. Convair Astronautics, San Diego (California

    Directory of Open Access Journals (Sweden)

    Pereira & Luckmam, Arquitectos

    1960-05-01

    Full Text Available Este brillante y espectacular complejo industrial se ha creado especialmente para la investigación y fabricación de cohetes intercontinentales y vehículos del espacio de las Fuerzas Aéreas de los EE. UU., en las proximidades de San Diego y cerca del campo de pruebas de Sycamore Canyon.

  8. Phytophthora ramorum causes cryptic bole cankers in Canyon line Oak

    Science.gov (United States)

    Unusual mortality of large canyon live oaks was observed in natural stands in San Mateo, California starting in 2007. A survey of affected stands showed that symptomatic trees were spatially associated with California bay, the primary source of Phytophthora ramorum spores in this forest type. Trunk ...

  9. Provenance and Detrital-Zircon Studies of the Mint Canyon Formation and its Correlation to the Caliente Formation, Southern California

    OpenAIRE

    hoyt, johanna

    2012-01-01

    The Middle Miocene Mint Canyon and Caliente formations represent sedimentation after triple-junction extension in southern California. Sandstone and conglomerate petrology, combined with detrital-zircon analysis, determines provenance of the Mint Canyon and Caliente formations. These data indicate that most detritus is locally derived, rather than being derived from the Chocolate Mountains across the San Andreas fault. The Mint Canyon and Caliente formations received Proterozoic anorthosite-s...

  10. Flow in bedrock canyons.

    Science.gov (United States)

    Venditti, Jeremy G; Rennie, Colin D; Bomhof, James; Bradley, Ryan W; Little, Malcolm; Church, Michael

    2014-09-25

    Bedrock erosion in rivers sets the pace of landscape evolution, influences the evolution of orogens and determines the size, shape and relief of mountains. A variety of models link fluid flow and sediment transport processes to bedrock incision in canyons. The model components that represent sediment transport processes are increasingly well developed. In contrast, the model components being used to represent fluid flow are largely untested because there are no observations of the flow structure in bedrock canyons. Here we present a 524-kilometre, continuous centreline, acoustic Doppler current profiler survey of the Fraser Canyon in western Canada, which includes 42 individual bedrock canyons. Our observations of three-dimensional flow structure reveal that, as water enters the canyons, a high-velocity core follows the bed surface, causing a velocity inversion (high velocities near the bed and low velocities at the surface). The plunging water then upwells along the canyon walls, resulting in counter-rotating, along-stream coherent flow structures that diverge near the bed. The resulting flow structure promotes deep scour in the bedrock channel floor and undercutting of the canyon walls. This provides a mechanism for channel widening and ensures that the base of the walls is swept clear of the debris that is often deposited there, keeping the walls nearly vertical. These observations reveal that the flow structure in bedrock canyons is more complex than assumed in the models presently used. Fluid flow models that capture the essence of the three-dimensional flow field, using simple phenomenological rules that are computationally tractable, are required to capture the dynamic coupling between flow, bedrock erosion and solid-Earth dynamics.

  11. 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.

  12. Geochemical fine-sediment tracers in San Francisco Bay and its outer coast: the role of local watersheds

    Science.gov (United States)

    Takesue, R. K.; Barnard, P. L.

    2012-12-01

    Sediment enters San Francisco Bay (SFB) through the Sacramento-San Joaquin River Delta, the Golden Gate, and local watersheds. Inputs from local watersheds have become increasingly important since the 1940s when large-scale impoundments began upstream of the Delta. The goals of this study are to determine whether fine sediment from local watersheds have distinct geochemical signatures, and if these can be used to determine whether locally-derived sediment accumulates in SFB. Retention of fine sediment is essential if accretion of shallow and intertidal habitats is to keep pace with sea level rise. Total contents of chromium (Cr), lanthanum (La), thorium (Th), zirconium (Zr), rare earth elements (REE), and twenty five other elements were determined by ICP-MS in the fine or "mud" fraction (<63 μm) of river, tributary, bay, and outer coast bed sediment. SFB and outer coast sediment was collected in January 2012 after a 5-day storm. River and tributary sediment was collected between 2010-2012. REE contents were normalized to a shale composite (NASC). In comparison to granitic material from the Sierra Nevada, local watersheds contain ultramafic Franciscan rocks in the Coast Range, volcanic deposits near Napa and Sonoma, and ancient marine sedimentary rocks. Fine sediment from the Sacramento River was enriched in heavy REE (HREENASC) and Cr, while that from the San Joaquin River was enriched in light REE (LREENASC) and Th. Petaluma River and Sonoma Creek fine sediments were distinguished by middle REE (MREENASC) enrichments and low Cr contents consistent with felsic volcanic rocks. In contrast, fine sediments in Napa River and Wildcat Creek had relatively flat REENASC patterns and intermediate to high Cr contents that suggest a Franciscan influence. The same was true for fine sediment in Marin creeks (Arroyo del Presidio and Corte Madera) and two South Bay tributaries (Guadelupe River and San Francisquito Creek). San Francisquito Creek fine sediment was uniquely

  13. 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

  14. New York Canyon Stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Raemy, Bernard

    2012-06-21

    The New York Canyon Stimulation Project was to demonstrate the commercial application of Enhanced Geothermal System techniques in Buena Vista Valley area of Pershing County, Nevada. From October 2009 to early 2012, TGP Development Company aggressively implemented Phase I of Pre-Stimulation and Site/Wellbore readiness. This included: geological studies; water studies and analyses and procurement of initial permits for drilling. Oversubscription of water rights and lack of water needed for implementation of EGS were identified and remained primary obstacles. Despite extended efforts to find alternative solutions, the water supply circumstances could not be overcome and led TGP to determine a "No Go" decision and initiate project termination in April 2012.

  15. Impact of oil and gas infrastructure development in La Manga Canyon, NM

    Science.gov (United States)

    La Manga Canyon is a small watershed (~20km2) in the San Juan Basin that has historically been developed for natural gas and recently for coal bed methane. Since gas production began in the 1940s, an extensive network of dirt roads have transected the watershed, providing access to well sites. There...

  16. 75 FR 12315 - Pacific Gas and Electric Company; Diablo Canyon Independent Spent Fuel Storage Installation...

    Science.gov (United States)

    2010-03-15

    ... fuel and associated radioactive materials resulting from the operation of the Diablo Canyon Nuclear... Ninth Circuit in San Luis Obispo Mothers for Peace v. NRC, 493 F.3d 1016 (9th Cir. 2006), and a related... SFSC Loading, Unloading, and Preparation Program,'' to clarify the maintenance of the required...

  17. 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...

  18. San Francisco District Laboratory (SAN)

    Data.gov (United States)

    Federal Laboratory Consortium — Program Capabilities Food Analysis SAN-DO Laboratory has an expert in elemental analysis who frequently performs field inspections of materials. A recently acquired...

  19. 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

    map area also includes Portuguese Ledge and Soquel Canyon State Marine Conservation Areas. Designated conservation and (or) recreation areas in the onshore part of the map area include Salinas River National Wildlife Refuge, Elkhorn Slough State Marine Conservation Area, Elkhorn Slough State Marine Reserve, Moss Landing Wildlife Area, Zmudowski and Salinas River State Beaches, and Marina Dunes Preserve.Monterey Bay, a geologically complex area within a tectonically active continental margin, lies between two major, converging strike-slip faults. The northwest-striking San Andreas Fault lies about 34 km east of Monterey Bay; this section of the fault ruptured in both the 1989 M6.9 Loma Prieta earthquake and the 1906 M7.8 great California earthquake. The northwest-striking San Gregorio Fault crosses Monterey Canyon west of Monterey Bay. Between these two regional faults, strain is accommodated by the northwest-striking Monterey Bay Fault Zone. Deformation associated with these major regional faults and related structures has resulted in uplift of the Santa Cruz Mountains, as well as the granitic highlands of the Monterey peninsula.Monterey Canyon begins in the nearshore area directly offshore of Moss Landing and Elkhorn Slough, and it can be traced for more than 400 km seaward, out to water depths of more than 4,000 m. Within the map area, the canyon can be traced for about 42 km to a water depth of about 1,520 m. The head of the canyon consists of three branches that begin about 150 m offshore of Moss Landing Harbor. At 500 m offshore, the canyon is already 70 m deep and 750 m wide. Large sand waves, which have heights from 1 to 3 m and wavelengths of about 50 m, are present along the channel axis in the upper 4 km of the canyon.Soquel Canyon is the most prominent tributary of Monterey Canyon within the map area. The head of Soquel Canyon is isolated from coastal watersheds and, thus, is considered inactive as a conduit for coarse sediment transport.North and south of

  20. Submarine canyons off Madras Coast

    Digital Repository Service at National Institute of Oceanography (India)

    Setty, M.G.A.P.

    Submarine canyons off the coast of Madras, Tamil Nadu, India were studied during cruise of @iINS Kistna@@ as part of the IIOE programme They consist of hill-like projections and V-shaped valleys Their other features are also reported...

  1. Geomorphic process fingerprints in submarine canyons

    Science.gov (United States)

    Brothers, Daniel S.; ten Brink, Uri S.; Andrews, Brian D.; Chaytor, Jason D.; Twichell, David C.

    2013-01-01

    Submarine canyons are common features of continental margins worldwide. They are conduits that funnel vast quantities of sediment from the continents to the deep sea. Though it is known that submarine canyons form primarily from erosion induced by submarine sediment flows, we currently lack quantitative, empirically based expressions that describe the morphology of submarine canyon networks. Multibeam bathymetry data along the entire passive US Atlantic margin (USAM) and along the active central California margin near Monterey Bay provide an opportunity to examine the fine-scale morphology of 171 slope-sourced canyons. Log–log regression analyses of canyon thalweg gradient (S) versus up-canyon catchment area (A) are used to examine linkages between morphological domains and the generation and evolution of submarine sediment flows. For example, canyon reaches of the upper continental slope are characterized by steep, linear and/or convex longitudinal profiles, whereas reaches farther down canyon have distinctly concave longitudinal profiles. The transition between these geomorphic domains is inferred to represent the downslope transformation of debris flows into erosive, canyon-flushing turbidity flows. Over geologic timescales this process appears to leave behind a predictable geomorphic fingerprint that is dependent on the catchment area of the canyon head. Catchment area, in turn, may be a proxy for the volume of sediment released during geomorphically significant failures along the upper continental slope. Focused studies of slope-sourced submarine canyons may provide new insights into the relationships between fine-scale canyon morphology and down-canyon changes in sediment flow dynamics.

  2. San Francisco District Laboratory (SAN)

    Data.gov (United States)

    Federal Laboratory Consortium — Program CapabilitiesFood Analysis SAN-DO Laboratory has an expert in elemental analysis who frequently performs field inspections of materials. A recently acquired...

  3. 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.

  4. Hazard assessment of inorganics to endangered fish in the San Juan River, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, S.J.; Buhl, K.J. [National Biological Service, Yankton, SD (United States)

    1995-12-31

    Acute toxicity tests were conducted with larval Colorado squawfish (Ptychocheilus lucius) and razorback sucker (Xyrauchen texanus) in a constituted water quality simulating the San Juan River near Shiprock, New Mexico. Tests were conducted with arsenate, copper, selenate, selenite, zinc, and five mixtures of seven to nine inorganics simulating environmental mixtures reported for sites along the San Juan River (Ojo Amarillo Canyon, Gallegos Canyon, Hogback East Drain, Mancos River, and McElmo Creek). Razorback suckers were significantly more sensitive to arsenate, selenate, selenite, Hogback East Drain mixture, and Ojo Amarillo Canyon mixture than were Colorado squawfish. The Gallegos Canyon mixture had greater than additive, i.e., synergistic, toxicity to both species, the Ojo Amarillo Canyon mixture had less than additive, i.e., antagonistic, toxicity to both species, and the Mancos River and McElmo Creek mixtures had additive toxicity to both species. The Hogback East Drain mixture had additive toxicity to Colorado squawfish, but synergistic toxicity to razorback suckers. The major toxic component in the five mixtures was copper. Comparison of 96-hour LC50 values with a limited number of environmental water concentrations from the San Juan River revealed high hazard ratios for copper and all five environmental mixtures. The high hazard ratios suggest inorganic contaminants could adversely affect larval Colorado squawfish and razorback suckers in the San Juan River at sites receiving elevated inorganics.

  5. San Marino.

    Science.gov (United States)

    1985-02-01

    San Marino, an independent republic located in north central Italy, in 1983 had a population of 22,206 growing at an annual rate of .9%. The literacy rate is 97% and the infant mortality rate is 9.6/1000. The terrain is mountainous and the climate is moderate. According to local tradition, San Marino was founded by a Christian stonecutter in the 4th century A.D. as a refuge against religious persecution. Its recorded history began in the 9th century, and it has survived assaults on its independence by the papacy, the Malatesta lords of Rimini, Cesare Borgia, Napoleon, and Mussolini. An 1862 treaty with the newly formed Kingdom of Italy has been periodically renewed and amended. The present government is an alliance between the socialists and communists. San Marino has had its own statutes and governmental institutions since the 11th century. Legislative authority at present is vested in a 60-member unicameral parliament. Executive authority is exercised by the 11-member Congress of State, the members of which head the various administrative departments of the goverment. The posts are divided among the parties which form the coalition government. Judicial authority is partly exercised by Italian magistrates in civil and criminal cases. San Marino's policies are tied to Italy's and political organizations and labor unions active in Italy are also active in San Marino. Since World War II, there has been intense rivalry between 2 political coalitions, the Popular Alliance composed of the Christian Democratic Party and the Independent Social Democratic Party, and the Liberty Committee, coalition of the Communist Party and the Socialist Party. San Marino's gross domestic product was $137 million and its per capita income was $6290 in 1980. The principal economic activities are farming and livestock raising, along with some light manufacturing. Foreign transactions are dominated by tourism. The government derives most of its revenue from the sale of postage stamps to

  6. Strontium isotopes reveal distant sources of architectural timber in Chaco Canyon, New Mexico

    Science.gov (United States)

    English, N.B.; Betancourt, J.L.; Dean, J.S.; Quade, Jay

    2001-01-01

    Between A.D. 900 and 1150, more than 200,000 conifer trees were used to build the prehistoric great houses of Chaco Canyon, New Mexico, in what is now a treeless landscape. More than one-fifth of these timbers were spruce (Picea) or fir (Abies) that were hand-carried from isolated mountaintops 75-100 km away. Because strontium from local dust, water, and underlying bedrock is incorporated by trees, specific logging sites can be identified by comparing 87Sr/86Sr ratios in construction beams from different ruins and building periods to ratios in living trees from the surrounding mountains. 87Sr/86Sr ratios show that the beams came from both the Chuska and San Mateo (Mount Taylor) mountains, but not from the San Pedro Mountains, which are equally close. Incorporation of logs from two sources in the same room, great house, and year suggest stockpiling and intercommunity collaboration at Chaco Canyon. The use of trees from both the Chuska and San Mateo mountains, but not from the San Pedro Mountains, as early as A.D. 974 suggests that selection of timber sources was driven more by regional socioeconomic ties than by a simple model of resource depletion with distance and time.

  7. Rocky-reef fish assemblages at San José Island, Mexico Asociaciones de peces de arrecifes rocosos en Isla San José, México

    Directory of Open Access Journals (Sweden)

    Carmen Amelia Villegas-Sánchez

    2009-04-01

    Full Text Available We analyzed the composition, diversity, and abundance of marine fish at rocky reefs off San José island, Mexico between October 2001 and August 2002. Fish species were recorded using a visual census in 5 sampling areas of 50 by 5 meters at 2 depths, shallow (1-3 meters and intermediate (5-7 meters. A total of 26 946 organisms were counted, belonging to 84 species. The families Serranidae (9 species, Labridae (8, Pomacentridae (7, and Haemulidae (6 were the most representative. We measured the rugosity of the bottom surface, which showed a positive relationship with abundance, richness, and fish diversity. The ocean bottom off San José island is covered with various size rocks that offer more feeding and refuge areas to fish assemblages than other areas. The ecological index increased during the warm season. Diversity and richness showed significant variations (PSe analizó la estructura íctica de los arrecifes rocosos de Isla San José, México entre octubre del 2001 y agosto del 2002. Las especies fueron registradas por medio de censos visuales, los cuales se realizaron sobre transectos de 50 m de largo X 5 m de ancho en 2 profundidades: somera (1-3 m e intermedia (5-7 m. Se contabilizaron un total de 26 946 individuos pertenecientes a 84 especies. Las familias mejor representadas fueron Serranidae (9, Labridae (8, Pomacentridae (7 y Haemulidae (6. La rugosidad del sustrato presentó una correlación positiva con la abundancia, riqueza y diversidad de especies de peces, lo que podría indicar que zonas con altos valores de rugosidad ofrecen a los peces más áreas de alimentación y refugio. Los índices ecológicos mostraron una tendencia de incremento de especies durante la temporada cálida. La diversidad y riqueza específica presentaron variaciones significativas entre profundidades (P<0.05, con valores más altos en los sitios expuestos de la isla ( Conejo, Pardito y San Francisquito. El índice de valor biológico indicó que las

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. À propos des variantes émergentes du canyoning dans le sud de l’Europe et en Amérique du Nord

    OpenAIRE

    Suchet, André

    2013-01-01

    Après avoir construit le concept d’éthique de pratique, cette recherche expose les cas du wild-boaring et du clean canyoneering qui constituent des variantes émergentes du canyoning. L’éthique du clean canyoneering, c’est-à-dire progresser techniquement sans poser de points fixes en canyon, s’inscrit dans une expérience précise du wilderness états-unien. À l’inverse, l’éthique du wild-boaring se compose d’un esprit de conquête, héritier de la spéléologie exploratoire et de l’alpinisme europée...

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. Flow dynamics around downwelling submarine canyons

    Science.gov (United States)

    Spurgin, J. M.; Allen, S. E.

    2014-10-01

    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.

  20. Great Houses and the Sun - Astronomy of Chaco Canyon

    Science.gov (United States)

    McKim Malville, J.; Munro, Andrew

    The primary axes of Basketmaker III pit structures at Shabik'eschee in Chaco Canyon have two orientations, one to the south and the other to the south-south-east. This architectural tradition continued with remarkable continuity throughout the San Juan Basin to the end of Pueblo III. Many of the Great Houses in Chaco, which appear to be massively enlarged front-facing unit pueblos typical of the Northern San Juan, continued this tradition. Orientations of the back walls of Great Houses to the solstice sun or standstill moon may never have been intended by the builders. Claimed inter-site alignments of Great Houses to minor or major standstill limits appear to be the results of local topography and not intended by the builders. Late Bonito phase (AD 1100-1140) Great Houses are distinguished by their planned designs, relatively short construction period, and negligible middens. Solstice sunrise or sunset horizon foresights are present at the majority of these Great Houses, which may have been designed in part to provide demonstrations of the astronomical knowledge of the Chacoan leadership.

  1. Distribution of DDT and other persistent organic contaminants in Canyons and on the continental shelf off the central California coast.

    Science.gov (United States)

    Hartwell, S Ian

    2008-04-01

    Sediment samples were collected to delineate the distribution of contaminants along the central California coast. Sampling included a variety of Canyons and shelf/slope areas to evaluate contaminant transport patterns and potential delivery to Canyons and the continental slope to a depth of 1200 m. Sediments were collected and analyzed for organic contaminants using standard techniques of the NOAA National Status and Trends Program (NS&T). DDT is distributed on the shelf within a zone of fine-grained sediments between Half Moon and Monterey Bays. DDT was found at higher concentrations in Ascension, Año Nuevo, and Monterey/Soquel Canyons than in Pioneer and Carmel Canyons, the Gulf of the Farallones, or the continental slope. The Monterey Bay watershed appears to be the primary source of DDT. In contrast, PAHs and PCBs on the shelf appear to be derived primarily from San Francisco Bay. DDT appears to be delivered to the deep ocean via the Canyons more than from cross-shelf sediment transport. Sediment budget estimates for the continental shelf north of Monterey Bay need further refinement and more data to account for the movement of material from Monterey Bay onto the shelf.

  2. 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...

  3. 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.

  4. 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

  5. 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...

  6. 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...

  7. 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...

  8. Flow Structure in a Bedrock Canyon (Invited)

    Science.gov (United States)

    Venditti, J. G.; Rennie, C. D.; Church, M. A.; Bomhof, J.; Lin, M.

    2013-12-01

    Bedrock canyon incision is widely recognized as setting the pace of landscape evolution. A variety of models link flow and sediment transport processes to the bedrock canyon incision rate. The model components that represent sediment transport processes are quite well developed in some models. In contrast, the model components that represent fluid flow remain rudimentary. Part of the reason is that there have been relatively few observations of flow structure in a bedrock canyon. Here, we present observations of flow obtained using an array of three acoustic Doppler current profilers during a 524 km long continuous centerline traverse of the Fraser River, British Columbia, Canada as it passes through a series of bedrock canyons. Through this portion of the river, the channel alternates between gravel-bedded reaches that are deeply incised into semi-consolidated glacial deposits and solid bedrock-bound reaches. We present observations of flow through 41 bedrock bound reaches of the river, derived from our centerline traverses and more detailed three-dimensional mapping of the flow structure in 2 canyons. Our observations suggest that flow in the most well-defined canyons (deep, laterally constrained, completely bedrock bound) is far more complex than that in a simple prismatic channel. As flow enters the canyon, a high velocity core plunges from the surface to the bed, causing a velocity inversion (high velocities at the bed and low velocities at the surface). This plunging flow then upwells along the canyon wall, resulting in a three-dimensional flow with counter-rotating, along-stream eddies that diverge near the bed. We observe centerline ridges along the canyon floors that result from the divergence and large-scale surface boils caused by the upwelling. This flow structure causes deep scour in the bedrock channel floor, and ensures the base of the canyon walls are swept of debris that otherwise may be deposited due to lower shear stresses abutting the walls. The

  9. Structure of Flow in a Bedrock Canyon

    Science.gov (United States)

    Venditti, J. G.; Rennie, C. D.; Church, M. A.; Bomhof, J.; Lin, M.

    2012-12-01

    Bedrock canyon incision is widely recognized as setting the pace of landscape evolution. A variety of models link flow and sediment transport processes to the bedrock canyon incision rate. The model components that represent sediment transport processes are quite well developed in some models. In contrast, the model components that represent fluid flow remain rudimentary. Part of the reason is that there have been relatively few observations of flow structure in a bedrock canyon. Here, we present observations of flow obtained using an array of three acoustic Doppler current profilers during a 524 km long continuous centerline traverse of the Fraser River, British Columbia, Canada as it passes through a series of bedrock canyons. Through this portion of the river, the channel alternates between gravel-bedded reaches that are deeply incised into semi-consolidated glacial deposits and solid bedrock-bound reaches. We present observations of flow through 41 bedrock bound reaches of the river, derived from our centerline traverses and more detailed three-dimensional mapping of the flow structure in 2 canyons. Our observations suggest that flow in the most well-defined canyons (deep, laterally constrained, completely bedrock bound) is far more complex than that in a simple prismatic channel. As flow enters the canyon, a high velocity core plunges from the surface to the bed, causing a velocity inversion (high velocities at the bed and low velocities at the surface). This plunging flow then upwells along the canyon wall, resulting in a three-dimensional flow with counter-rotating, along-stream eddies that diverge near the bed. We observe centerline ridges along the canyon floors that result from the divergence and large-scale surface boils caused by the upwelling. This flow structure causes deep scour in the bedrock channel floor, and ensures the base of the canyon walls are swept of debris that otherwise may be deposited due to lower shear stresses abutting the walls. The

  10. 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.

  11. Different Views of the Grand Canyon

    Science.gov (United States)

    Elders, Wilfred A.

    Each year the spectacular scenery of the Grand Canyon of Arizona awes its more than 4,000,000 visitors. Just as its enormous scale dwarfs our human sense of space, its geology also dwarfs our human sense of time. Perhaps here, more than anywhere else on the planet, we can experience a sense of ``Deep Time.'' The colorful rocks exposed in the vertical walls of the canyon display a span of 1.8 billion years of Earth's history [Beus and Morales, 2003]. But wait! There is a different view! According to Vail [2003], this time span is only 6,000 years and the Grand Canyon and its rocks are a record of the Biblical 6 days of creation and Noah's flood. During a visit to Grand Canyon, in August 2003, I learned that Vail's book, Grand Canyon: A Different View, is being sold within the National Park. The author and compiler of Grand Canyon: A Different View is a Colorado River guide who is well acquainted with the Grand Canyon at river level. He has produced a book with an attractive layout and beautiful photographs. The book is remarkable because it has 23 co-authors, all male, who comprise a veritable ``Who's Who'' in creationism. For example, Henry Morris and John Whitcomb, the authors of the seminal young Earth creationist text, The Genesis Flood [Whitcomb and Morris, 1961], each contribute a brief introduction. Each chapter of Grand Canyon: A Different View begins with an overview by Vail, followed by brief comments by several contributors that ``have been peer reviewed to ensure a consistent and Biblical perspective.'' This perspective is strict Biblical literalism.

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

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    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.

  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. 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.

  16. Grand Canyon Humpback Chub Population Improving

    Science.gov (United States)

    Andersen, Matthew E.

    2007-01-01

    The humpback chub (Gila cypha) is a long-lived, freshwater fish found only in the Colorado River Basin. Physical adaptations-large adult body size, large predorsal hump, and small eyes-appear to have helped humpback chub evolve in the historically turbulent Colorado River. A variety of factors, including habitat alterations and the introduction of nonnative fishes, likely prompted the decline of native Colorado River fishes. Declining numbers propelled the humpback chub onto the Federal list of endangered species in 1967, and the species is today protected under the Endangered Species Act of 1973. Only six populations of humpback chub are currently known to exist, five in the Colorado River Basin above Lees Ferry, Ariz., and one in Grand Canyon, Ariz. The U.S. Geological Survey's Grand Canyon Monitoring and Research Center oversees monitoring and research activities for the Grand Canyon population under the auspices of the Glen Canyon Dam Adaptive Management Program (GCDAMP). Analysis of data collected through 2006 suggests that the number of adult (age 4+ years) humpback chub in Grand Canyon increased to approximately 6,000 fish in 2006, following an approximate 40-50 percent decline between 1989 and 2001. Increasing numbers of adult fish appear to be the result of steadily increasing numbers of juvenile fish reaching adulthood beginning in the mid- to late-1990s and continuing through at least 2002.

  17. Deciphering Outburst Flood Discharges from the Morphology of Hesperian Canyons

    Science.gov (United States)

    Lapotre, M. G. A.; Lamb, M. P.; Williams, R. M.

    2014-07-01

    We model the hydraulics of outburst floods over canyon escarpments. We show that canyons only maintain a constant width under a certain hydraulic regime. We combine the hydraulic model to an erosion law to constrain paleodischarges at Echus Chasma.

  18. Contemporary sediment-transport processes in submarine canyons.

    Science.gov (United States)

    Puig, Pere; Palanques, Albert; Martín, Jacobo

    2014-01-01

    Submarine canyons are morphological incisions into continental margins that act as major conduits of sediment from shallow- to deep-sea regions. However, the exact mechanisms involved in sediment transfer within submarine canyons are still a subject of investigation. Several studies have provided direct information about contemporary sedimentary processes in submarine canyons that suggests different modes of transport and various triggering mechanisms. Storm-induced turbidity currents and enhanced off-shelf advection, hyperpycnal flows and failures of recently deposited fluvial sediments, dense shelf-water cascading, canyon-flank failures, and trawling-induced resuspension largely dominate present-day sediment transfer through canyons. Additionally, internal waves periodically resuspend ephemeral deposits within canyons and contribute to dispersing particles or retaining and accumulating them in specific regions. These transport processes commonly deposit sediments in the upper- and middle-canyon reaches for decades or centuries before being completely or partially flushed farther down-canyon by large sediment failures.

  19. 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

  20. 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...

  1. 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...

  2. 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...

  3. 77 FR 22801 - Glen Canyon Dam Adaptive Management Work Group

    Science.gov (United States)

    2012-04-17

    ... Bureau of Reclamation Glen Canyon Dam Adaptive Management Work Group AGENCY: Bureau of Reclamation... Management Work Group (AMWG) makes recommendations to the Secretary of the Interior concerning Glen Canyon... AMP includes a Federal advisory committee, the AMWG, a technical work group, a Grand Canyon...

  4. 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...

  5. Morphology of Neptune Node Sites, Barkley Canyon, Cascadia Margin

    Science.gov (United States)

    Lundsten, E. M.; Anderson, K.; Paull, C. K.; Caress, D. W.; Thomas, H. J.; Riedel, M.

    2014-12-01

    High-resolution multibeam bathymetry and chirp seismic reflection profiles collected with MBARI's mapping autonomous underwater vehicle reveal the fine-scale morphology and shallow seafloor structure of the flanks and floor of Barkley Canyon on the Cascadia continental margin off British Columbia. The surveys characterize the environment surrounding three nodes on the Neptune Canada cabled observatory located within the canyon. The canyon floor between 960 and 1020 m water depth lacks channeling and contains ≥ 24 m of acoustically uniform sediment fill, which is ponded between the canyon's steep sidewalls. The fill overlies a strong reflector that outlines an earlier, now buried, canyon floor channel system. Debris flow tongues contain meter scale blocks sticking-up through the fill. Apparently the present geomorphology surrounding the Canyon Axis node in 985 m is attributable to local debris flows, rather than organized down canyon processes. In the survey area the canyon sidewalls extend ~300 m up and in places the slope of the canyons sides exceed 40°. Both the Hydrate node in 870 m water depths and the Mid-Canyon node at 890 m are located on a headland that forms intermediate depth terraces on the canyon's western flank. While the seafloor immediately surrounding the Mid-canyon node is smooth, the Hydrate node is marked by 10 circular mounds up to 2 m high and 10 m in diameter, presumable associated with hydrate formation. Although wedges of sediment drape occur in places on the canyon sides, the chirp profiles show no detectible sediment drape at either node site and suggest these nodes are situated on older, presumably pre-Quaternary strata. The lack of reflectors in the chirp profiles indicates most of the canyon's sidewalls are largely sediment-bare. Lineations in the bathymetry mark the exposed edges of truncated beds. Rough, apparently fresh textures, within slide scarps show the importance of erosion on the development of the canyon flanks.

  6. 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

    map area also includes Portuguese Ledge and Soquel Canyon State Marine Conservation Areas. Designated conservation and (or) recreation areas in the onshore part of the map area include Salinas River National Wildlife Refuge, Elkhorn Slough State Marine Conservation Area, Elkhorn Slough State Marine Reserve, Moss Landing Wildlife Area, Zmudowski and Salinas River State Beaches, and Marina Dunes Preserve.Monterey Bay, a geologically complex area within a tectonically active continental margin, lies between two major, converging strike-slip faults. The northwest-striking San Andreas Fault lies about 34 km east of Monterey Bay; this section of the fault ruptured in both the 1989 M6.9 Loma Prieta earthquake and the 1906 M7.8 great California earthquake. The northwest-striking San Gregorio Fault crosses Monterey Canyon west of Monterey Bay. Between these two regional faults, strain is accommodated by the northwest-striking Monterey Bay Fault Zone. Deformation associated with these major regional faults and related structures has resulted in uplift of the Santa Cruz Mountains, as well as the granitic highlands of the Monterey peninsula.Monterey Canyon begins in the nearshore area directly offshore of Moss Landing and Elkhorn Slough, and it can be traced for more than 400 km seaward, out to water depths of more than 4,000 m. Within the map area, the canyon can be traced for about 42 km to a water depth of about 1,520 m. The head of the canyon consists of three branches that begin about 150 m offshore of Moss Landing Harbor. At 500 m offshore, the canyon is already 70 m deep and 750 m wide. Large sand waves, which have heights from 1 to 3 m and wavelengths of about 50 m, are present along the channel axis in the upper 4 km of the canyon.Soquel Canyon is the most prominent tributary of Monterey Canyon within the map area. The head of Soquel Canyon is isolated from coastal watersheds and, thus, is considered inactive as a conduit for coarse sediment transport.North and south of

  7. 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....

  8. 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...

  9. Submarine canyons off the Coromandel coast

    Digital Repository Service at National Institute of Oceanography (India)

    Varadachari, V.V.R.; Nair, R.R.; Murty, P.S.N.

    During the 26th Cruise of I.N.S. `KISTNA', a bathymetric survey was carried out in some detail off the Pondicherry coast. This survey has revealed the existence of three sets of distinctly separate canyons between Cuddalore and Palar River...

  10. 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.

  11. Differences in health symptoms among residents living near illegal dump sites in Los Laureles Canyon, Tijuana, Mexico: a cross sectional survey.

    Science.gov (United States)

    Al-Delaimy, Wael K; Larsen, Catherine Wood; Pezzoli, Keith

    2014-09-15

    Living near landfills is a known health hazard prompting recognition of environmental injustice. The study aim was to compare self-reported symptoms of ill health among residents of four neighborhoods, living in haphazardly constructed settlements surrounded by illegal dumpsites in Tijuana, Mexico. One adult from each of 388 households located in Los Laureles Canyon were interviewed about demographics, health status, and symptoms. Distance from each residence to both the nearest dumpsite and the canyon bottom was assessed. The neighborhoods were selected from locations within the canyon, and varied with respect to proximity to dump sites. Residents of San Bernardo reported significantly higher frequencies of ill-health symptoms than the other neighborhoods, including extreme fatigue (OR 3.01 (95% CI 1.6-5.5)), skin problems/irritations (OR 2.73 (95% CI 1.3-5.9)), stomach discomfort (OR 2.47 (1.3-4.8)), eye irritation/tears (OR 2.02 (1.2-3.6)), and confusion/difficulty concentrating (OR 2.39 (1.2-4.8)). Proximity to dumpsites did not explain these results, that varied only slightly when adjusted for distance to nearest dumpsite or distance to the canyon bottom. Because San Bernardo has no paved roads, we hypothesize that dust and the toxicants it carries is a possible explanation for this difference. Studies are needed to further document this association and sources of toxicants.

  12. Creationism in the Grand Canyon, Texas Textbooks

    Science.gov (United States)

    Folger, Peter

    2004-01-01

    AGU President Bob Dickinson, together with presidents of six other scientific societies, have written to Joseph Alston, Superintendent of Grand Canyon National Park, pointing out that a creationist book, The Grand Canyon: A Different View, is being sold in bookstores within the borders of the park as a scientific explanation about Grand Canyon geologic history. President Dickinson's 16 December letter urges that Alston clearly separate The Grand Canyon: A Different View from books and materials that discuss the legitimate scientific understanding of the origin of the Grand Canyon. The letter warns the Park Service against giving the impression that it approves of the anti-science movement known as young-Earth creationism, or that it endorses the advancement of religious tenets disguised as science. The text of the letter is on AGU's Web site http://www.agu.org/sci_soc/policy/sci_pol.html. Also, this fall, AGU sent an alert to Texas members about efforts by intelligent design creationists aimed at weakening the teaching of biological evolution in textbooks used in Texas schools. The alert pointed scientists to a letter, drafted by AGU, together with the American Institute of Physics, the American Physical Society, the Optical Society of America, and the American Astronomical Society, that urged the Texas State Board of Education to adopt textbooks that presented only accepted, peer-reviewed science and pedagogical expertise. Over 550 scientists in Texas added their names to the letter (http://www.agu.org/sci_soc/policy/texas_textbooks.pdf ), sent to the Board of Education on 1 November prior to their vote to adopt a slate of new science textbooks. The Board voted 11-5 in favor of keeping the textbooks free of changes advocated by groups supporting intelligent design creationism.

  13. 77 FR 54811 - Safety Zone; TriRock San Diego, San Diego Bay, San Diego, CA

    Science.gov (United States)

    2012-09-06

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; TriRock San Diego, San Diego Bay, San Diego... safety zone upon the navigable waters of the San Diego Bay, San Diego, CA, in support of a bay swim in San Diego Harbor. This safety zone is necessary to provide for the safety of the participants, crew...

  14. 78 FR 58878 - Safety Zone; San Diego Shark Fest Swim; San Diego Bay, San Diego, CA

    Science.gov (United States)

    2013-09-25

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Diego Shark Fest Swim; San Diego Bay, San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a safety zone upon the navigable waters of the San Diego Bay, San Diego, CA, in support of San...

  15. 78 FR 53243 - Safety Zone; TriRock San Diego, San Diego Bay, San Diego, CA

    Science.gov (United States)

    2013-08-29

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; TriRock San Diego, San Diego Bay, San Diego... temporary safety zone upon the navigable waters of the San Diego Bay, San Diego, CA, in support of a... Bryan Gollogly, Waterways Management, U.S. Coast Guard Sector San Diego; telephone (619) 278-7656, email...

  16. 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

  17. Westernmost Grand Canyon incision: Testing thermochronometric resolution

    Science.gov (United States)

    Fox, M.; Tripathy-Lang, A.; Shuster, D. L.; Winn, C.; Karlstrom, K.; Kelley, S.

    2017-09-01

    The timing of carving of Grand Canyon has been debated for over 100 years with competing endmember hypotheses advocating for either a 70 Ma (;old;) or history and corresponding estimates of landscape evolution have been in debate. In particular, 4He/3He thermochronometric data record the distribution of radiogenic 4He (from the 238U, 235U and 232Th decay series) within an individual apatite crystal and thus are highly sensitive to the thermal history corresponding to landscape evolution. However, there are several complicating factors that make interpreting such data challenging in geologic scenarios involving reheating. Here, we analyze new data that provide measures of the cooling of basement rocks at the base of westernmost Grand Canyon, and use these data as a testbed for exploring the resolving power and limitations of 4He/3He data in general. We explore a range of thermal histories and find that these data are most consistent with a ;young; Grand Canyon. A problem with the recovered thermal history, however, is that burial temperatures are under predicted based on sedimentological evidence. A solution to this problem is to increase the resistance of alpha recoil damage to annealing, thus modifying He diffusion kinetics, allowing for higher temperatures throughout the thermal history. This limitation in quantifying radiation damage (and hence crystal retentivity) introduces non-uniqueness to interpreting time-temperature paths in rocks that resided in the apatite helium partial retention zone for long durations. Another source of non-uniqueness, is due to unknown U and Th distributions within crystals. We show that for highly zoned with a decrease in effective U of 20 ppm over the outer 80% of the radius of the crystal, the 4He/3He data could be consistent with an ;old; canyon model. To reduce this non-uniqueness, we obtain U and Th zonation information for separate crystals from the same rock sample through LA-ICP-MS analysis. The observed U and Th

  18. 3D View of Grand Canyon, Arizona

    Science.gov (United States)

    2000-01-01

    The Grand Canyon is one of North America's most spectacular geologic features. Carved primarily by the Colorado River over the past six million years, the canyon sports vertical drops of 5,000 feet and spans a 445-kilometer-long stretch of Arizona desert. The strata along the steep walls of the canyon form a record of geologic time from the Paleozoic Era (250 million years ago) to the Precambrian (1.7 billion years ago).The above view was acquired by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument aboard the Terra spacecraft. Visible and near infrared data were combined to form an image that simulates the natural colors of water and vegetation. Rock colors, however, are not accurate. The image data were combined with elevation data to produce this perspective view, with no vertical exaggeration, looking from above the South Rim up Bright Angel Canyon towards the North Rim. The light lines on the plateau at lower right are the roads around the Canyon View Information Plaza. The Bright Angel Trail, which reaches the Colorado in 11.3 kilometers, can be seen dropping into the canyon over Plateau Point at bottom center. The blue and black areas on the North Rim indicate a forest fire that was smoldering as the data were acquired on May 12, 2000.Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, Calif., is the U.S. Science team leader; Moshe Pniel of JPL is the project manager. ASTER is the only high resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as

  19. Stratigraphy, sedimentology and paleontology of lower Eocene San Jose formation, central San Juan basin, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Lucas, S.G.; Smith, L.N. (New Mexico Museum of Natural History, Albuquerque (USA))

    1989-09-01

    The lower Eocene San Jose Formation in the central portion of the San Juan basin (Gobernador-Vigas Canyon area) consists of the Cuba Mesa, Regina, Llaves, and Tapicitos Members. Well log data indicate that, from its 100-m thickness, the Cuba Mesa Member thins toward the basin center and pinches out to the northeast by lat. 36{degree}40'N, long. 107{degree}19'W. The Regina Member has the most extensive outcrops in the central basin, and it decreases in sandstone/mud rock ratio to the north. The Llaves and Tapicitos Members occur only at the highest elevations, are thin due to erosion, and are not mappable as separate units. Well log data and 1,275 m of measured stratigraphic section in the Regina, Llaves, and Tapicitos Members indicate these strata are composed of approximately 35% medium to coarse-grained sandstone and 65% fine-grained sandstone and mud rock. Sedimentology and sediment-dispersal patterns indicate deposition by generally south-flowing streams that had sources to the northwest, northeast, and east. Low-sinuosity, sand-bedded, braided( ) streams shifted laterally across about 1 km-wide channel belts to produce sheet sandstones that are prominent throughout the San Jose Formation. Subtle levees separated channel environments from floodplain and local lacustrine areas. Avulsion relocated channels periodically to areas on the floodplain, resulting in the typically disconnected sheet sandstones within muddy overbank deposits of the Regina Member.

  20. Surprise and Opportunity for Learning in Grand Canyon: the Glen Canyon Dam Adaptive Management Program

    Directory of Open Access Journals (Sweden)

    Theodore S. Melis

    2015-09-01

    Full Text Available 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.

  1. 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 sta......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...... 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....

  2. “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.”

  3. Horseshoe Canyon and Mannville case studies

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, T. [Trident Exploration Corp., Calgary, AB (Canada)

    2005-07-01

    This presentation outlined the coalbed methane (CBM) activities underway at Trident Exploration Corp. with particular reference to the results achieved in the Horseshoe Canyon and Mannville formations. In order to be commercially successful, companies drilling for unconventional gas must spend millions of dollars testing and evaluating different drilling, completion and production methods. Early regional exploration programs are also important to gain an understanding of the economics of each particular play. The Horseshoe Canyon play extends for more than 250 miles and is 100 miles wide. Most of the wells drilled to date have been drilled by a few large operators, including Trident. Most of the Horseshoe Canyon is greatly underpressured and there may not be enough gas in place in some areas to justify drilling for the coals alone. The coal properties within the Horseshoe Canyon vary widely from well to well. The total coal thickness ranges from less than 5 to more than 30 metres. The number of seams per well varies from 8 to 25 and the average seam thickness is 1 metre. The well depths range from 150 metres in the east to more than 900 metres in the west. The Mannville is among the largest CBM resources in western Canada, with estimates of up to several hundred trillion cubic feet of recoverable reserves. Trident operates the largest and longest running Mannville pilot at Corbett, northwest of Edmonton. The pilot wells have shown the area has good quality coal, excellent gas content and good permeability. As of February 2005, there are 47 active producers, 2 disposal wells and 3 observation wells. Average production per well is 1.5 E{sup 3}m{sup 3} gas per day and 17 m{sup 3} water per day. Declining water production on individual wells along with limited gas production and high reservoir pressure suggests that the wells are progressively damaged. Initial experience with horizontal wells at Corbett has proved to be encouraging. figs.

  4. Atmospheric and soil-gas monitoring for surface leakage at the San Juan Basin CO{sub 2} pilot test site at Pump Canyon New Mexico, using perfluorocarbon tracers, CO{sub 2} soil-gas flux and soil-gas hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Wells, Arthur W; Diehl, J Rodney; Strazisar, Brian R; Wilson, Thomas; H Stanko, Dennis C

    2012-05-01

    Near-surface monitoring and subsurface characterization activities were undertaken in collaboration with the Southwest Regional Carbon Sequestration Partnership on their San Juan Basin coal-bed methane pilot test site near Navajo City, New Mexico. Nearly 18,407 short tons (1.670 × 107 kg) of CO{sub 2} were injected into 3 seams of the Fruitland coal between July 2008 and April 2009. Between September 18 and October 30, 2008, two additions of approximately 20 L each of perfluorocarbon (PFC) tracers were mixed with the CO{sub 2} at the injection wellhead. PFC tracers in soil-gas and in the atmosphere were monitored over a period of 2 years using a rectangular array of permanent installations. Additional monitors were placed near existing well bores and at other locations of potential leakage identified during the pre-injection site survey. Monitoring was conducted using sorbent containing tubes to collect any released PFC tracer from soil-gas or the atmosphere. Near-surface monitoring activities also included CO{sub 2} surface flux and carbon isotopes, soil-gas hydrocarbon levels, and electrical conductivity in the soil. The value of the PFC tracers was demonstrated when a significant leakage event was detected near an offset production well. Subsurface characterization activities, including 3D seismic interpretation and attribute analysis, were conducted to evaluate reservoir integrity and the potential that leakage of injected CO{sub 2} might occur. Leakage from the injection reservoir was not detected. PFC tracers made breakthroughs at 2 of 3 offset wells which were not otherwise directly observable in produced gases containing 20–30% CO{sub 2}. These results have aided reservoir geophysical and simulation investigations to track the underground movement of CO{sub 2}. 3D seismic analysis provided a possible interpretation for the order of appearance of tracers at production wells.

  5. 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.

  6. Assessing GPS Constellation Resiliency in an Urban Canyon Environment

    Science.gov (United States)

    2015-03-26

    Assessing GPS Constellation Resiliency in an Urban Canyon Environment THESIS MARCH 2015 Aaron J. Burns, Second Lieutenant, USAF AFIT-ENS-MS-15-M-138...URBAN CANYON ENVIRONMENT THESIS Presented to the Faculty Department of Operational Sciences Graduate School of Engineering and Management Air Force...UNLIMITED. AFIT-ENS-MS-15-M-138 ASSESSING GPS CONSTELLATION RESILIENCY IN AN URBAN CANYON ENVIRONMENT Aaron J. Burns, B.S. Second Lieutenant, USAF Committee

  7. Post-Miocene Right Separation on the San Gabriel and Vasquez Creek Faults, with Supporting Chronostratigraphy, Western San Gabriel Mountains, California

    Science.gov (United States)

    Beyer, Larry A.; McCulloh, Thane H.; Denison, Rodger E.; Morin, Ronald W.; Enrico, Roy J.; Barron, John A.; Fleck, Robert J.

    2009-01-01

    The right lateral San Gabriel Fault Zone in southern California extends from the northwestern corner of the Ridge Basin southeastward to the eastern end of the San Gabriel Mountains. It bifurcates to the southeast in the northwestern San Gabriel Mountains. The northern and older branch curves eastward in the range interior. The southern younger branch, the Vasquez Creek Fault, curves southeastward to merge with the Sierra Madre Fault Zone, which separates the San Gabriel Mountains from the northern Los Angeles Basin margin. An isolated exposure of partly macrofossiliferous nearshore shallow-marine sandstone, designated the Gold Canyon beds, is part of the southwest wall of the fault zone 5.5 km northwest of the bifurcation. These beds contain multiple subordinate breccia-conglomerate lenses and are overlain unconformably by folded Pliocene-Pleistocene Saugus Formation fanglomerate. The San Gabriel Fault Zone cuts both units. Marine macrofossils from the Gold Canyon beds give an age of 5.2+-0.3 Ma by 87Sr/86Sr analyses. Magnetic polarity stratigraphy dates deposition of the overlying Saugus Formation to between 2.6 Ma and 0.78 Ma. Distinctive metaplutonic rocks of the Mount Lowe intrusive suite in the San Gabriel Range are the source of certain clasts in both the Gold Canyon beds and Saugus Formation. Angular clasts of nondurable Paleocene sandstone also occur in the Gold Canyon beds. The large size and angularity of some of the largest of both clast types in breccia-conglomerate lenses of the beds suggest landslides or debris flows from steep terrain. Sources of Mount Lowe clasts, originally to the north or northeast, are now displaced southeastward by faulting and are located between the San Gabriel and Vasquez Creek faults, indicating as much as 12+-2 km of post-Miocene Vasquez Creek Fault right separation, in accord with some prior estimates. Post-Miocene right slip thus transferred onto the Vasquez Creek Fault southeast of the bifurcation. The right separation

  8. 77 FR 70147 - Fish and Wildlife Service 0648-XB088

    Science.gov (United States)

    2012-11-23

    ... Madera, Bear, Dennis Martin, Sausal, and Alambique creeks, and portions of San Francisquito, Los Trancos, Corte Madera, and Bear creeks flow through Stanford lands. The Matadero/Deer Creek watershed is entirely...

  9. Results of the Multi-Jurisdictional Conference on the Farmworker and Day Laborer Housing Crisis (San Diego, California, February 21, 1991).

    Science.gov (United States)

    San Diego City Council, CA.

    In February 1991, policymakers and representatives of resource agencies and nonprofit organizations met to find solutions to a major regional crisis--the lack of housing for farmworkers and day laborers in San Diego County. The region contains about 200 worker camps, usually situated in undeveloped canyons and fields near suburban residential…

  10. Mobile Monitoring of Methane During and After the Aliso Canyon Natural Gas Leak

    Science.gov (United States)

    Polidori, A.; Pikelnaya, O.; Low, J.; Wimmer, R.; Zhou, Q.

    2016-12-01

    The Aliso Canyon gas leak was discovered inside the SoCalGas (SCG) facility on October 23, 2015. This incident represented the worst natural gas leak in the US history, and spurred a number of odor nuisance complaints from local residents. The community of Porter Ranch, located directly south of the SCG Aliso Canyon facility, was the most affected by the leak although complaints have been also reported in other neighboring communities of the San Fernando Valley. Therefore, monitoring of air quality was and remains crucial for measuring the impact of methane emissions from this leak and assessing the well-being of all residents. As the main local air quality agency for this area, South Coast Air Quality Management District (SCAQMD) organized a set of monitoring activities in response to the leak. Since December 21, 2015 SCAQMD has been conducting mobile survey measurements in and around Porter Ranch to characterize methane levels and concentration gradients within the community. For this purpose, a fast-response optical methane analyzer (LI-COR 7700) and a Global Positioning System (GPS) were mounted on top of a hybrid vehicle and driven around Porter Ranch and other surrounding areas. Following the permanent seal of the leaking well on February 18, 2016 mobile measurements have also been expanded to inside the Aliso Canyon SCG facility. During this presentation we will describe the experimental setup designed for mobile methane surveys and the monitoring strategy used for this study. We will discuss the main results of our mobile measurements including long-term methane trends since the end of the leak.

  11. SAN CARLOS APACHE PAPERS.

    Science.gov (United States)

    ROESSEL, ROBERT A., JR.

    THE FIRST SECTION OF THIS BOOK COVERS THE HISTORICAL AND CULTURAL BACKGROUND OF THE SAN CARLOS APACHE INDIANS, AS WELL AS AN HISTORICAL SKETCH OF THE DEVELOPMENT OF THEIR FORMAL EDUCATIONAL SYSTEM. THE SECOND SECTION IS DEVOTED TO THE PROBLEMS OF TEACHERS OF THE INDIAN CHILDREN IN GLOBE AND SAN CARLOS, ARIZONA. IT IS DIVIDED INTO THREE PARTS--(1)…

  12. San Carlo Operaen

    DEFF Research Database (Denmark)

    Holm, Bent

    2005-01-01

    En indplacering af operahuset San Carlo i en kulturhistorisk repræsentationskontekst med særligt henblik på begrebet napolalità.......En indplacering af operahuset San Carlo i en kulturhistorisk repræsentationskontekst med særligt henblik på begrebet napolalità....

  13. 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)...

  14. 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.

  15. Wave run up in Zones of Underwater Canyons

    Directory of Open Access Journals (Sweden)

    Katline Koblev A. Julio

    2013-01-01

    Full Text Available The wave run up on coast and shore protection constructions in zones of underwater canyons is considered. The mathematical model of wave run up on the coast, considering distinctions in biases of underwater and surface parts of the coastal slope, allowing to receive setup parameters in zones of the underwater canyons, corresponding to data of supervision is offered.

  16. 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...

  17. 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...

  18. 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

  19. Transfer processes in a simulated urban street canyon

    Science.gov (United States)

    Solazzo, E.; Britter, R. E.

    2007-07-01

    The transfer processes within and above a simulated urban street canyon were investigated in a generic manner. Computational fluid dynamics (CFD) was used to aid understanding and to produce some simple operational parameterisations. In this study we addressed specifically the commonly met situation where buoyancy effects arising from elevated surface temperatures are not important, i.e. when mechanical forces outweigh buoyancy forces. In a geophysical context this requires that some suitably defined Richardson number is small. From an engineering perspective this is interpreted as the important case when heat transfer within and above urban street canyons is by forced convection. Surprisingly, this particular scenario (for which the heat transfer coefficient between buildings and the flow is largest), has been less well studied than the situation where buoyancy effects are important. The CFD technique was compared against wind-tunnel experiments to provide model evaluation. The height-to-width ratio of the canyon was varied through the range 0.5 5 and the flow was normal to the canyon axis. By setting the canyon’s facets to have the same or different temperatures or to have a partial temperature distribution, simulations were carried out to investigate: (a) the influence of geometry on the flow and mixing within the canyon and (b) the exchange processes within the canyon and across the canyon top interface. Results showed that the vortex-type circulation and turbulence developed within the canyon produced a temperature distribution that was, essentially, spatially uniform (apart from a relatively thin near-wall thermal boundary layer) This allowed the temperatures within the street canyon to be specified by just one value T can , the canyon temperature. The variation of T can with wind speed, surface temperatures and geometry was extensively studied. Finally, the exchange velocity u E across the interface between the canyon and the flow above was calculated

  20. Internal tide convergence and mixing in a submarine canyon

    Science.gov (United States)

    Waterhouse, Amy

    2016-11-01

    Observations from Eel Canyon, located on the north coast of California, show that elevated turbulence in the full water column arises from the convergence of remotely-generated internal wave energy. The incoming semidiurnal and bottom-trapped diurnal internal tides generate complex interference patterns. The semidiurnal internal tide sets up a partly standing wave within the canyon due to reflection at the canyon head, dissipating all of its energy within the canyon. Dissipation in the near-bottom is associated with the diurnal trapped tide, while midwater isopycnal shear and strain is associated with the semidiurnal tide. Dissipation is elevated up to 600 m off the bottom, in contrast to observations over flat continental shelf where dissipation occurs closer to the topography. Slope canyons are sinks for internal wave energy and may have important influences on the global distribution of tidally-driven mixing.

  1. 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

  2. Canyon conditions impact carbon flows in food webs of three sections of the Nazaré canyon

    NARCIS (Netherlands)

    Van Oevelen, D.; Soetaert, K.E.R.; Garcia, R.; De Stigter, H.; Cunha, M.R.; Pusceddu, A.; Danovaro, 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 Nazaré canyon (eastern

  3. 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.

  4. 75 FR 76650 - Proposed Modification of Class E Airspace; Bryce Canyon, UT

    Science.gov (United States)

    2010-12-09

    ... Federal Aviation Administration 14 CFR Part 71 Proposed Modification of Class E Airspace; Bryce Canyon, UT...: This action proposes to modify Class E airspace at Bryce Canyon, UT to accommodate Area Navigation... airspace extending upward from 700 feet above the surface at Bryce Canyon Airport, Bryce Canyon,...

  5. Bottom-trawling along submarine canyons impacts deep sedimentary regimes

    Science.gov (United States)

    Paradis, Sarah; Puig, Pere; Masqué, Pere; Juan-Díaz, Xènia; Martín, Jacobo; Palanques, Albert

    2017-01-01

    Many studies highlight that fish trawling activities cause seafloor erosion, but the assessment of the remobilization of surface sediments and its relocation is still not well documented. These impacts were examined along the flanks and axes of three headless submarine canyons incised on the Barcelona continental margin, where trawling fleets have been operating for decades. Trawled grounds along canyon flanks presented eroded and highly reworked surface sediments resulting from the passage of heavy trawling gear. Sedimentation rates on the upper canyon axes tripled and quadrupled its natural (i.e. pre-industrialization) values after a substantial increase in total horsepower of the operating trawling fleets between 1960 s and 1970 s. These impacts affected the upper canyon reaches next to fishing grounds, where sediment resuspended by trawling can be transported towards the canyon axes. This study highlights that bottom trawling has the capacity to alter natural sedimentary environments by promoting sediment-starved canyon flanks, and by enhancing sedimentation rates along the contiguous axes, independently of canyons’ morphology. Considering the global mechanisation and offshore expansion of bottom trawling fisheries since the mid-20th century, these sedimentary alterations may occur in many trawled canyons worldwide, with further ecological impacts on the trophic status of these non-resilient benthic communities. PMID:28233856

  6. A Karst Connection model for Grand Canyon, Arizona, USA

    Science.gov (United States)

    Hill, C. A.; Eberz, N.; Buecher, R. H.

    2008-03-01

    A new model for the connection of the eastern and western Grand Canyon is proposed that involves westward flow of Redwall karst aquifer water under the Kaibab arch along the steepest hydraulic gradient to discharge at a structural low in a headward-eroding protowestern Grand Canyon. A karst-aquifer hydrological connection was first established between the eastern and western Grand Canyon, then collapse, incision, and headward erosion of the canyon followed this subterranean route. This proposed model is based on what is happening today on the northern Marble Platform where the Redwall-Muav aquifer is still intact. The three sinkhole/caves Ah Hol Sah, Indian Pit, and Black Abyss provide vertical flow routes down to the Redwall karst aquifer, joining water discharging from the Kaiparowits hydrologic basin to the Colorado River along the Fence Springs system. Projecting this process back in time and spatially southward, we propose that at around 6 Ma a sinkhole or sinkholes existed at the confluence of the Colorado River with the Little Colorado River. Little Colorado River water, then flowing northward to an interior lake basin ("Glen Lake") in southern Utah, became pirated down this sinkhole(s), thus causing a reversal of drainage (barbed tributaries) in Marble Canyon. Headward erosion then proceeded up Marble and Little Colorado Canyons from the collapsing sinkhole, with Marble Canyon incision breaching Glen Lake at around 5.5 Ma. This effected the "final connection" and total integration of the Colorado River from Colorado to the Gulf of California.

  7. High-resolution seafloor mapping surveys over the San Gregorio-Palo Colorado Fault

    Science.gov (United States)

    Paull, C. K.; Caress, D. W.; Thomas, H.; Lundsten, E.; Anderson, K.; Gwiazda, R.

    2011-12-01

    The San Gregorio-Palo Colorado Fault (SGPCF) is mapped as traversing the outer end of Monterey Bay and crossing Monterey Canyon near its intersection with Carmel Canyon. The location of the fault is based on offsets in seismic reflection profiles, lineations in the bathymetry, and locations of epicenters associated with small earthquakes. However, much of the offshore area where the trace of the SGPCF is postulated to be located is sediment bare, making it difficult to determine if there has been recent movement along this segment of the fault. High-resolution multibeam bathymetry (vertical precision of 0.15 m and horizontal resolution of 1.0 m) and 1-4.5 kHz chirp seismic reflection profiles have recently been collected in up to 1.6 km water depths on the northern flank of Monterey Canyon where the SGPCF is thought to cut across the canyon wall. The objective of these surveys was to look for indications of recent deformation associated with the SGPCF where accumulations of sediments could provide evidence of seafloor displacement along this segment of the fault since these sediments have been deposited. The surveys were conducted using an autonomous underwater vehicle (AUV) during two 17.5-hour-long dives. An inertial navigation system combined with a Doppler velocity sonar allowed the AUV to fly pre-programmed grids at 3 knots while maintaining an altitude of 50 m above the seafloor. These surveys are in addition to other recently published AUV surveys of the floor of Monterey Canyon extending out to 2.2 km water depths and including the zone where the SGPCF is mapped to cross the canyon floor. The lack of clear evidence of fault deformation along the SGPCF trace on the canyon floor is easily attributable to frequent sediment transport events within the canyon's channel, which would presumably overwrite sediment deformation associated with the SGPCF. The surveys presented here extend above the active canyon floor and cover the northern flank of Monterey Canyon

  8. Liquid-filled canyons on Titan

    Science.gov (United States)

    Poggiali, V.; Mastrogiuseppe, M.; Hayes, A. G.; Seu, R.; Birch, S. P. D.; Lorenz, R.; Grima, C.; Hofgartner, J. D.

    2016-08-01

    In May 2013 the Cassini RADAR altimeter observed channels in Vid Flumina, a drainage network connected to Titan's second largest hydrocarbon sea, Ligeia Mare. Analysis of these altimeter echoes shows that the channels are located in deep (up to 570 m), steep-sided, canyons and have strong specular surface reflections that indicate they are currently liquid filled. Elevations of the liquid in these channels are at the same level as Ligeia Mare to within a vertical precision of about 0.7 m, consistent with the interpretation of drowned river valleys. Specular reflections are also observed in lower order tributaries elevated above the level of Ligeia Mare, consistent with drainage feeding into the main channel system.

  9. New hexactinellid sponges from deep Mediterranean canyons.

    Science.gov (United States)

    Boury-Esnault, Nicole; Vacelet, Jean; Dubois, Maude; Goujard, Adrien; Fourt, Maïa; Pérez, Thierry; Chevaldonné, Pierre

    2017-02-21

    During the exploration of the NW Mediterranean deep-sea canyons (MedSeaCan and CorSeaCan cruises), several hexactinellid sponges were observed and collected by ROV and manned submersible. Two of them appeared to be new species of Farrea and Tretodictyum. The genus Farrea had so far been reported with doubt from the Mediterranean and was listed as "taxa inquirenda" for two undescribed species. We here provide a proper description for the specimens encountered and sampled. The genus Tretodictyum had been recorded several times in the Mediterranean and in the near Atlantic as T. tubulosum Schulze, 1866, again with doubt, since the type locality is the Japan Sea. We here confirm that the Mediterranean specimens are a distinct new species which we describe. We also provide18S rDNA sequences of the two new species and include them in a phylogenetic tree of related hexactinellids.

  10. 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...

  11. 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 in...

  12. 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 in...

  13. 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...

  14. 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...

  15. 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...

  16. Investigations of Carbon Phases in Canyon Diablo Meteorite

    Science.gov (United States)

    Karczemska, A.; Jakubowski, T.; Ouzillou, M.; Batory, D.; Abramczyk, H.; Brozek-Pluska, B.; Kopec, M.; Kozanecki, M.; Wiosna-Salyga, G.

    2016-08-01

    X-ray diffraction, Raman mapping and micro-spectrofluorimetric studies have been used in investigations of carbon in Canyon Diablo meteorite. Results show the presence of defected diamond and not well recognized carbon phases (unclear Raman peaks).

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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.

  3. 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...

  4. 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...

  5. 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

  6. 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.

  7. 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.

  8. CARBON AND OXYGEN ISOTOPIC ANALYSIS: BUG, CHEROKEE, AND PATTERSON CANYON FIELDS, SAN JUAN COUNTY, UTAH

    Energy Technology Data Exchange (ETDEWEB)

    David E. Eby; Thomas C. Chidsey Jr; Kevin McClure; Craig D. Morgan; Stephen T. Nelson

    2003-12-01

    Over 400 million barrels (64 million m{sup 3}) of oil have been produced from the shallow-shelf carbonate reservoirs in the Pennsylvanian (Desmoinesian) Paradox Formation in the Paradox Basin, Utah and Colorado. With the exception of the giant Greater Aneth field, the other 100 plus oil fields in the basin typically contain 2 to 10 million barrels (0.3-1.6 million m{sup 3}) of original oil in place. Most of these fields are characterized by high initial production rates followed by a very short productive life (primary), and hence premature abandonment. Only 15 to 25 percent of the original oil in place is recoverable during primary production from conventional vertical wells. An extensive and successful horizontal drilling program has been conducted in the giant Greater Aneth field. However, to date, only two horizontal wells have been drilled in small Ismay and Desert Creek fields. The results from these wells were disappointing due to poor understanding of the carbonate facies and diagenetic fabrics that create reservoir heterogeneity. These small fields, and similar fields in the basin, are at high risk of premature abandonment. At least 200 million barrels (31.8 million m{sup 3}) of oil will be left behind in these small fields because current development practices leave compartments of the heterogeneous reservoirs undrained. Through proper geological evaluation of the reservoirs, production may be increased by 20 to 50 percent through the drilling of low-cost single or multilateral horizontal legs from existing vertical development wells. In addition, horizontal drilling from existing wells minimizes surface disturbances and costs for field development, particularly in the environmentally sensitive areas of southeastern Utah and southwestern Colorado.

  9. Simulation of ground-water flow and solute transport in the Glen Canyon aquifer, East-Central Utah

    Science.gov (United States)

    Freethey, Geoffrey W.; Stolp, Bernard J.

    2010-01-01

    The extraction of methane from coal beds in the Ferron coal trend in central Utah started in the mid-1980s. Beginning in 1994, water from the extraction process was pressure injected into the Glen Canyon aquifer. The lateral extent of the aquifer that could be affected by injection is about 7,600 square miles. To address regional-scale effects of injection over a decadal time frame, a conceptual model of ground-water movement and transport of dissolved solids was formulated. A numerical model that incorporates aquifer concepts was then constructed and used to simulate injection. The Glen Canyon aquifer within the study area is conceptualized in two parts-an active area of ground-water flow and solute transport that exists between recharge areas in the San Rafael Swell and Desert, Waterpocket Fold, and Henry Mountains and discharge locations along the Muddy, Dirty Devil, San Rafael, and Green Rivers. An area of little or negligible ground-water flow exists north of Price, Utah, and beneath the Wasatch Plateau. Pressurized injection of coal-bed methane production water occurs in this area where dissolved-solids concentrations can be more than 100,000 milligrams per liter. Injection has the potential to increase hydrologic interaction with the active flow area, where dissolved-solids concentrations are generally less than 3,000 milligrams per liter. Pressurized injection of coal-bed methane production water in 1994 initiated a net addition of flow and mass of solutes into the Glen Canyon aquifer. To better understand the regional scale hydrologic interaction between the two areas of the Glen Canyon aquifer, pressurized injection was numerically simulated. Data constraints precluded development of a fully calibrated simulation; instead, an uncalibrated model was constructed that is a plausible representation of the conceptual flow and solute-transport processes. The amount of injected water over the 36-year simulation period is about 25,000 acre-feet. As a result

  10. Multibeam bathymetry and selected perspective views offshore San Diego, California

    Science.gov (United States)

    Dartnell, Peter; Normark, William R.; Driscoll, Neal W.; Babcock, Jeffrey M.; Gardner, James V.; Kvitek, Rikk G.; Iampietro, Pat J.

    2007-01-01

    This set of two posters consists of a map on one sheet and a set of seven perspective views on the other. The ocean floor image was generated from multibeam-bathymetry data acquired by Federal and local agencies as well as academic institutions including: - U.S. Geological Survey mapped from the La Jolla Canyon south to the US-Mexico border using a Kongsberg Simrad multibeam echosounder system (MBES) (March - April 1998). Data and metadata available at http://pubs.usgs.gov/of/2004/1221/. - Woods Hole Oceanographic Institution and SCRIPPS Institution of Oceanography mapped the majority of the La Jolla Fan Valley including the sea floor to the north and south of the valley using a Seabeam 2100 MBES. Data available at http://www.ngdc.noaa.gov/mgg/bathymetry/multibeam.html. Survey ID, AT07L09, Chief Scientists, Barrie Walden and Joseph Coburn (April 2002). - California State University, Monterey Bay, mapped Scripps Canyon and the head of La Jolla Canyon using a Reson 8101 MBES (October 2001). Data and metadata available at http://seafloor.csumb.edu/SFMLwebDATA.htm. This work was funded by the California Department of Fish and Game California Coastal Conservancy, San Diego Association of Governments (SANDAG), California Department of Fish and Game, and Fugro Pelagos mapped the nearshore region out to about 35-40 m. - The sea floor within this image that has not been mapped with MBES is filled in with interpreted bathymetry gridded from single-beam data available at http://www.ngdc.noaa.gov/mgg/bathymetry/hydro.html. Depths are in meters below sea level, which is referenced to Mean Lower Low Water.

  11. San Pascual (1989) n. 272

    OpenAIRE

    Pérez, María Dolores, O.S.C. (Directora)

    1989-01-01

    Editorial. Entrevista madre abadesa. Ofrenda. San Pascual tercer centenario de la canonizacion y cuarto de su muerte. San Pascual, un Santo universal. Pascual Baylón, poeta. grupo Scout Sant Pasqual. Aportaciones, donativos, limosnas, benefactores. Boletin informativo del templo de San Pascual de villareal.

  12. 87Sr/86Sr sourcing of ponderosa pine used in Anasazi great house construction at Chaco Canyon, New Mexico

    Science.gov (United States)

    Reynolds, Amanda C.; Betancourt, Julio L.; Quade, Jay; Patchett, P. Jonathan; Dean, Jeffery S.; Stein, John

    2005-01-01

    Previous analysis of 87Sr/86Sr ratios shows that 10th through 12th century Chaco Canyon was provisioned with plant materials that came from more than 75 km away. This includes (1) corn (Zea mays) grown on the eastern flanks of the Chuska Mountains and floodplain of the San Juan River to the west and north, and (2) spruce (Picea sp.) and fir (Abies sp.) beams from the crest of the Chuska and San Mateo Mountains to the west and south. Here, we extend 87Sr/86Sr analysis to ponderosa pine (Pinus ponderosa) prevalent in the architectural timber at three of the Chacoan great houses (Pueblo Bonito, Chetro Ketl, Pueblo del Arroyo). Like the architectural spruce and fir, much of the ponderosa matches the 87Sr/86Sr ratios of living trees in the Chuska Mountains. Many of the architectural ponderosa, however, have similar ratios to living trees in the La Plata and San Juan Mountains to the north and Lobo Mesa/Hosta Butte to the south. There are no systematic patterns in spruce/fir or ponderosa provenance by great house or time, suggesting the use of stockpiles from a few preferred sources. The multiple and distant sources for food and timber, now based on hundreds of isotopic values from modern and archeological samples, confirm conventional wisdom about the geographic scope of the larger Chacoan system. The complexity of this procurement warns against simple generalizations based on just one species, a single class of botanical artifact, or a few isotopic values.

  13. Effects of canyon geometry on the distribution of traffic-related air pollution in a large urban area: Implications of a multi-canyon air pollution dispersion model

    Science.gov (United States)

    Fu, Xiangwen; Liu, Junfeng; Ban-Weiss, George A.; Zhang, Jiachen; Huang, Xin; Ouyang, Bin; Popoola, Olalekan; Tao, Shu

    2017-09-01

    Street canyons are ubiquitous in urban areas. Traffic-related air pollutants in street canyons can adversely affect human health. In this study, an urban-scale traffic pollution dispersion model is developed considering street distribution, canyon geometry, background meteorology, traffic assignment, traffic emissions and air pollutant dispersion. In the model, vehicle exhausts generated from traffic flows first disperse inside street canyons along the micro-scale wind field generated by computational fluid dynamics (CFD) model. Then, pollutants leave the street canyon and further disperse over the urban area. On the basis of this model, the effects of canyon geometry on the distribution of NOx and CO from traffic emissions were studied over the center of Beijing. We found that an increase in building height leads to heavier pollution inside canyons and lower pollution outside canyons at pedestrian level, resulting in higher domain-averaged concentrations over the area. In addition, canyons with highly even or highly uneven building heights on each side of the street tend to lower the urban-scale air pollution concentrations at pedestrian level. Further, increasing street widths tends to lead to lower pollutant concentrations by reducing emissions and enhancing ventilation simultaneously. Our results indicate that canyon geometry strongly influences human exposure to traffic pollutants in the populated urban area. Carefully planning street layout and canyon geometry while considering traffic demand as well as local weather patterns may significantly reduce inhalation of unhealthy air by urban residents.

  14. 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

    weather stations, like SEKI, the addition or subtraction of even a single weather station through time has the potential to significantly bias trends in interpolated data. In particular, this analysis was motivated by our questioning of some PRISM results presented in Appendix 1 (Landscape Context) that compared temperature averages between two 30-year periods of the 20th Century. Figures 6 and 11 of Appendix 1 indicate that recent (1971-2000) temperatures in northern Kings Canyon National Park averaged some 2° C cooler than those of 1911-1940. This would represent a truly profound and persistent cooling, and seems to be at odds both with the glacial retreats observed in the area over the century (Basagic 2008), and with the reported PRISM warming of nearly 2° C just to the west of the cooling (see Figs. 6 and 11 in Appendix 1). We suspect that the extreme localized Kings Canyon cooling reported by PRISM is an artifact of sparsely-distributed weather stations in the region being added and discontinued over the span of the 20th Century. For example, data from the Western Regional Climate Center (http://www.wrcc.dri.edu/coopmap/) suggest that for the period 1911 through 1924 PRISM must interpolate northern Kings Canyon temperatures based on a few low-elevation stations -- separated by hundreds of kilometers -- in Nevada and California’s San Joaquin Valley. In contrast, by 1970 PRISM interpolations will be dominated by closer, higher-elevation stations (see this report). The single weather station closest to northern Kings Canyon that has a temperature record at least partly spanning Appendix 1’s two

  15. Circulation in Vilkitsky Canyon in the eastern Arctic Ocean

    Science.gov (United States)

    Janout, Markus; Hölemann, Jens

    2016-04-01

    The eastern Arctic Ocean is characterized by steep continental slopes and vast shallow shelf seas that receive a large amount of riverine freshwater from some of the largest rivers on earth. The northwestern Laptev Sea is of particular interest, as it is a freshwater transport pathway for a swift surface-intensified current from the Kara Sea toward the Arctic Basin, as was recently highlighted by high-resolution model studies. The region features complex bathymetry including a narrow strait and a large submarine canyon, strong tides, polynyas and severe sea ice conditions throughout much of the year. A year-long mooring record as well as detailed hydrographic shipboard measurements resulted from summer expeditions to the area in 2013 and 2014, and now provide a detailed picture of the region's water properties and circulation. The hydrography is characterized by riverine Kara Sea freshwater near the surface in the southern part of the canyon, while warmer (~0°C) saline Atlantic-derived waters dominate throughout the canyon at depths >150m. Cold shelf-modified waters near the freezing point are found along the canyon edges. The mean flow at the 300 m-deep mooring location near the southern edge of the canyon is swift (30 cm/s) and oriented eastward near the surface as suggested by numerical models, while the deeper flow follows the canyon topography towards the north-east. Wind-driven deviations from the mean flow coincide with sudden changes in temperature and salinity. This study characterizes the general circulation in Vilkitsky Canyon and investigates its potential as a conduit for upwelling of Atlantic-derived waters from the Arctic Basin to the Laptev Sea shelf.

  16. Valley aggradation in the San Gabriel Mountains, California: climate change versus catastrophic landslide

    Science.gov (United States)

    Scherler, D.; Lamb, M. P.; Rhodes, E. J.; Avouac, J. P.

    2014-12-01

    The San Gabriel Mountains (SGM) in Southern California, rate amongst the most rapidly uplifting and eroding mountains in the United States. Their steep slopes and sensitivity to wildfires, flash floods, landslides, and debris flows account for imminent hazards to nearby urban areas that might be accentuated by climatic and other environmental changes. Previous studies suggested that river terraces along the North Fork of the San Gabriel River, record temporal variations in sediment supply and river transport capacity that are representative for the SGM and related to climatic changes during the Quaternary. Based on field observations, digital topographic analysis, and dating of Quaternary deposits, we suggest that valley aggradation in the North Fork San Gabriel Canyon was spatially confined and a consequence of the sudden supply of unconsolidated material to upstream reaches by one of the largest known landslides in the SGM. New 10Be-derived surface exposure ages from the landslide deposits, previously assumed to be early to middle Pleistocene in age, indicate at least three Holocene events at ~8-9 ka, ~4-5 ka, and ~0.5-1 ka. The oldest landslide predates the valley aggradation period, which is constrained by existing 14C ages and new luminescence ages to ~7-8 ka. The spatial distribution, morphology, and sedimentology of the river terraces are consistent with deposition from far-travelling debris flows that originated within the landslide deposits. Valley aggradation in the North Fork San Gabriel Canyon therefore resulted from locally enhanced sediment supply that temporarily overwhelmed river capacity but the lack of similar deposits in other parts of the SGM argues against a regional climatic signal. So far, there exists no evidence that in the San Gabriel Mountains, climatic changes can cause sustained increases in hillslope sediment supply that lead to river aggradation and terrace formation.

  17. 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.

  18. Preliminary Geologic Map of the San Fernando 7.5' Quadrangle, Southern California: A Digital Database

    Science.gov (United States)

    Yerkes, R.F.

    1997-01-01

    The city of San Fernando sits atop a structurally complex, sedimentologically diverse, and tectonically evolving late Tertiary-Quaternary basin situated within the Transverse Ranges of southern California. The surrounding San Fernando Valley (SFV) contains the headwaters of the Los Angeles River and its tributaries. Prior to the advent of flood control, the valley floor was composed of active alluvial fans and floodplains. Seasonal streams emanating from Pacoima and Big Tujunga Canyons drain the complex western San Gabriel Mountains and deposit coarse, highly permeable alluvium that contains generally high-quality ground water. The more shallow western part derives mainly from Tertiary and pre-Tertiary sedimentary rocks, and is underlain by less permeable, fine-grained deposits containing persistent shallow ground water and poorer water quality. Home of the 1971 San Fernando and the 1994 Northridge earthquakes, the SFV experienced near-record levels of strong ground motion in 1994 that caused widespread damage from strong shaking and ground failure. A new map of late Quaternary deposits of the San Fernando area shows that the SFV is a structural trough that has been filled from the sides, with the major source of sediment being large drainages in the San Gabriel Mountains. Deposition on the major alluvial fan of Tujunga Wash and Pacoima Wash, which issues from the San Gabriel Mountains, and on smaller fans, has been influenced by ongoing compressional tectonics in the valley. Late Pleistocene deposits have been cut by active faults and warped over growing folds. Holocene alluvial fans are locally ponded behind active uplifts. The resulting complex pattern of deposits has a major effect on liquefaction hazards. Young sandy sediments generally are highly susceptible to liquefaction where they are saturated, but the distribution of young deposits, their grain size characteristics, and the level of ground water all are complexly dependent on the tectonics of the valley

  19. Origin of Hot Creek Canyon, Long Valley caldera, California

    Energy Technology Data Exchange (ETDEWEB)

    Maloney, N.J. (California State Univ., Fullerton, CA (United States). Dept. of Geological Sciences)

    1993-04-01

    Hot Creek has eroded a canyon some thirty meters deep across the Hot Creek rhyolite flows located in the southeastern moat of Long Valley Caldera. Maloney (1987) showed that the canyon formed by headward erosion resulting from spring sapping along hydrothermally altered fractures in the rhyolite, and the capture of Mammoth Creek. This analysis ignored the continuing uplift of the central resurgent dome. Reid (1992) concluded that the downward erosion of the canyon must have kept pace with the uplift. Long Valley Lake occupied the caldera until 100,000 to 50,000 years before present. The elevation of the shoreline, determined by trigonometric leveling, is 2,166 m where the creek enters the canyon and 2,148 m on the downstream side of the rhyolite. The slope of the strand line is about equal to the stream gradient. The hill was lower and the stream gradient less at the time of stream capture. Rotational uplift increased the stream gradient which increased the rate of downward erosion and formed the V-shaped canyon

  20. 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,...

  1. 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.

  2. 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...

  3. Water classification of the Colorado River Corridor, Grand Canyon, Arizona, 2013—Data

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data area classified maps of water in the Colorado River at a discharge of approximately 227 meters squared/second in Grand Canyon from Glen Canyon Dam to...

  4. Riparian vegetation classification of the Colorado River Corridor, Grand Canyon, Arizona, 2013—Data

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data are classification maps of total riparian vegetation along the Colorado River in Grand Canyon from Glen Canyon Dam to Pearce Ferry in Arizona. The data...

  5. 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,...

  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. Directed urban canyons in megacities and its applications in meteorological modeling

    Science.gov (United States)

    Samsonov, Timofey; Konstantinov, Pavel; Varentsov, Mikhail

    2015-04-01

    Directed urban canyons study applies object-oriented analysis to extraction of urban canyons and introduces the concept of directed urban canyon which is then experimentally applied in urban meteorological modeling. Observation of current approach to description of urban canyon geometry is provided. Then a new theoretical approach to canyon delineation is presented that allows chaining the spaces between buildings into directed canyons that comprise three-level hierarchy. An original methodology based on triangular irregular network (TIN) is presented that allows extraction of regular and directed urban canyons from cartographic data, estimation of their geometric characteristics, including local and averaged height-width ratio, primary and secondary canyon directions. Obtained geometric properties of canyons are then applied in micro-scale temperature and wind modeling using URB-MOS model and estimation of possible wind accelerations along canyons. Extraction and analysis of directed canyons highly depends on the presence of linear street network. Thus, in the absence of this GIS layer, it should be reconstructed from another data sources. The future studies should give us an answer to the question, where the limits of directed canyons are and how they can be classified further in terms of the street longitudinal shape. For now all computations are performed in separate scripts and programs. We plan to develop comprehensive automation of described methods of urban canyon description in specialized software. The most perspective extension of proposed methodology seemes to be canyon -based analysis which is truely object-oriented. Various geometric properties of micro-, meso- and macro-scale canyons should be investigated and their applicability in urban climate modeling should be assesed. Object-oriented canyon analysis can also be applied in architectural studies, urban morphology, planning and various physical and social aspects that are concerned with human in

  8. Canyon conditions impact carbon flows in food webs of three sections of the Nazaré canyon

    Science.gov (United States)

    van Oevelen, Dick; Soetaert, Karline; Garcia, R.; de Stigter, Henko C.; Cunha, Marina R.; Pusceddu, Antonio; Danovaro, Roberto

    2011-12-01

    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 Nazaré canyon (eastern Atlantic Ocean) using linear inverse modeling to examine how the food web is influenced by the characteristics of the respective canyon section. The models were based on an empirical dataset consisting of biomass and carbon processing data, and general physiological data constraints from the literature. Environmental conditions, most notably organic matter (OM) input and hydrodynamic activity, differed between the canyon sections and strongly affected the benthic food web structure. Despite the large difference in depth, the OM inputs into the food webs of the upper and middle sections were of similar magnitude (7.98±0.84 and 9.30±0.71 mmol C m -2 d -1, respectively). OM input to the lower section was however almost 6-7 times lower (1.26±0.03 mmol C m -2 d -1). Carbon processing in the upper section was dominated by prokaryotes (70% of total respiration), though there was a significant meiofaunal (21%) and smaller macrofaunal (9%) contribution. The high total faunal contribution to carbon processing resembles that found in shallower continental shelves and upper slopes, although the meiofaunal contribution is surprisingly high and suggest that high current speeds and sediment resuspension in the upper canyon favor the role of the meiofauna. The high OM input and conditions in the accreting sediments of the middle canyon section were more beneficial for megafauna (holothurians), than for the other food web compartments. The high megafaunal biomass (516 mmol C m -2), their large contribution to respiration (56% of total respiration) and secondary production (0.08 mmol C m -2 d -1) shows that these accreting sediments in canyons are megafaunal hotspots in the deep

  9. Standardized methods for Grand Canyon fisheries research 2015

    Science.gov (United States)

    Persons, William R.; Ward, David L.; Avery, Luke A.

    2013-01-01

    This document presents protocols and guidelines to persons sampling fishes in the Grand Canyon, to help ensure consistency in fish handling, fish tagging, and data collection among different projects and organizations. Most such research and monitoring projects are conducted under the general umbrella of the Glen Canyon Dam Adaptive Management Program and include studies by the U.S. Geological Survey (USGS), U.S. Fish and Wildlife Service (FWS), National Park Service (NPS), the Arizona Game and Fish Department (AGFD), various universities, and private contractors. This document is intended to provide guidance to fieldworkers regarding protocols that may vary from year to year depending on specific projects and objectives. We also provide herein documentation of standard methods used in the Grand Canyon that can be cited in scientific publications, as well as a summary of changes in protocols since the document was first created in 2002.

  10. 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...). The Refuge has units located in Canyon, Owyhee, Payette, and Washington Counties, ID, and Malheur... the Snake River located in Canyon, Payette, Owyhee, and Washington Counties in ID; and Malheur...

  11. 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...

  12. 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...

  13. Measuring currents in submarine canyons: technological and scientific progress in the past 30 years

    Science.gov (United States)

    Xu, J. P.

    2011-01-01

    The development and application of acoustic and optical technologies and of accurate positioning systems in the past 30 years have opened new frontiers in the submarine canyon research communities. This paper reviews several key advancements in both technology and science in the field of currents in submarine canyons since the1979 publication of Currents in Submarine Canyons and Other Sea Valleys by Francis Shepard and colleagues. Precise placements of high-resolution, high-frequency instruments have not only allowed researchers to collect new data that are essential for advancing and generalizing theories governing the canyon currents, but have also revealed new natural phenomena that challenge the understandings of the theorists and experimenters in their predictions of submarine canyon flow fields. Baroclinic motions at tidal frequencies, found to be intensified both up canyon and toward the canyon floor, dominate the flow field and control the sediment transport processes in submarine canyons. Turbidity currents are found to frequently occur in active submarine canyons such as Monterey Canyon. These turbidity currents have maximum speeds of nearly 200 cm/s, much smaller than the speeds of turbidity currents in geological time, but still very destructive. In addition to traditional Eulerian measurements, Lagrangian flow data are essential in quantifying water and sediment transport in submarine canyons. A concerted experiment with multiple monitoring stations along the canyon axis and on nearby shelves is required to characterize the storm-trigger mechanism for turbidity currents.

  14. 75 FR 39147 - Establishment of Class E Airspace; Bryce Canyon, UT

    Science.gov (United States)

    2010-07-08

    ... Federal Aviation Administration 14 CFR Part 71 Establishment of Class E Airspace; Bryce Canyon, UT AGENCY... E airspace at Bryce Canyon, UT, to accommodate aircraft using a new Area Navigation (RNAV) Global... Bryce Canyon, UT (74 FR 59492). The comments received prompted the FAA on April 26, 2010, to publish...

  15. 75 FR 21532 - Proposed Establishment of Class E Airspace; Bryce Canyon, UT

    Science.gov (United States)

    2010-04-26

    ..., UT AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Supplemental notice of proposed... surface airspace at Bryce Canyon Airport, Bryce Canyon, UT. In a NPRM published in the Federal Register... Airport, Bryce Canyon, UT (74 FR 59492). The comment period closed January 4, 2010. Two comments...

  16. 76 FR 14802 - Modification of Class E Airspace; Bryce Canyon, UT

    Science.gov (United States)

    2011-03-18

    ... Federal Aviation Administration 14 CFR Part 71 Modification of Class E Airspace; Bryce Canyon, UT AGENCY... airspace at Bryce Canyon, UT. Additional controlled airspace is necessary to accommodate aircraft using... a notice of proposed rulemaking to establish additional controlled airspace at Bryce Canyon, UT...

  17. 75 FR 55975 - Safety Zone; San Diego Harbor Shark Fest Swim; San Diego Bay, San Diego, CA

    Science.gov (United States)

    2010-09-15

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Diego Harbor Shark Fest Swim; San Diego Bay, San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone upon the navigable waters of the San Diego Bay, San Diego, CA, in support...

  18. Hurricane effects on the coastline from Cabo San Lucas Bay, Baja California Peninsula, Mexico

    Science.gov (United States)

    Nava-Sanchez, Enrique; Navarro-Lozano, Octavio; Murillo-Jimenez, Janette; Godinez-Orta, Lucio

    2010-05-01

    Cabo San Lucas, located on the southern tip of the Baja California Peninsula, is on the track of two to five hurricanes per year. Thus the purpose of this work was to evaluate the effects of hurricanes on the stability of the coastline of San Lucas Bay. We apply GIS for determining inland geomorphology and conducted bathymetric surveys for the marine area. Results from previous sedimentological researches of fluvial, littoral and shallow marine environments were reanalyzed to determine the sedimentary processes responsible for the stability of the coastline. Also, we were monitoring beach profiles in the bay and also other beaches from the tip of the peninsula from 1997 to 2004 and recorded the effects of Hurricane Juliette in 2001 (category 3 in the Saffir-Simpson scale), which left an accumulative precipitation of 850 mm and formed waves of 8 m in height during the four days of maximum impact. We found out that inland and marine geomorphology, as well as littoral and alluvial sediment transport play a major role to keep the coastline relatively stable for at least the last 3,000 years. Geomorphology of the drainage basin is steep favoring the formation of flash floods that feed an alluvial fan to finally discharge sediments to the San Lucas Bay where a temporal fan-delta is developed during catastrophic rains. Marine morphology is dominated by the San Lucas submarine canyon, located on the southern half of the bay, whose canyon head is just at the foot of the beach (4 to 6 m in depth). On the northern half, there is a narrow submarine terrace with a break 40 m deep, covered mostly by fluvial sediments. At the littoral, there is only one dune ridge which is almost continuous and only cut by the arroyo. The dune ridge was dated at two levels; at the bottom, just above Pleistocene fluvial sediments and at the top, giving dates of 3200 and 800 years respectively. These dates are interpreted as an evidence for the stability of the dune ridge. The sand from the beach

  19. 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

  20. 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.

  1. Surprise and Opportunity for Learning in Grand Canyon: the Glen Canyon Dam Adaptive Management Program

    Science.gov (United States)

    Melis, T. S.; Walters, C. J.; Korman, J.

    2013-12-01

    With a focus on resources of the Colorado River ecosystem downstream of Glen Canyon Dam in Glen Canyon National Recreation Area (GCNRA) and Grand Canyon National Park (GCNP) of northern Arizona, the Glen Canyon Dam Adaptive Management Program has evaluated experimental flow and nonflow policy tests since 1990. Flow experiments have consisted of a variety of water releases from the dam within pre-existing annual downstream delivery agreements. The daily experimental dam operation, termed the Modified Low Fluctuating Flow (MLFF), implemented in 1996 to increase daily low flows and decrease daily peaks were intended to limit daily flow range to conserve tributary sand inputs and improve navigation among other objectives, including hydropower energy. Other flow tests have included controlled floods with some larger releases bypassing the dam's hydropower plant to rebuild and maintain eroded sandbars in GCNP. Experimental daily hydropeaking tests beyond MLFF have also been evaluated for managing the exotic recreational rainbow trout fishery in the dam's GCNRA tailwater. Experimental nonflow policies, such as physical removal of exotic fish below the tailwater, and experimental translocation of endangered native humpback chub from spawning habitats in the Little Colorado River (the largest natal origin site for chub in the basin) to other tributaries within GCNP have also been monitored. None of these large-scale field experiments has yet produced unambiguous results in terms of management prescriptions, owing to inadequate monitoring programs and confounding of treatment effects with effects of ongoing natural changes; most notably, a persistent warming of the river resulting from reduced storage in the dam's reservoir after 2003. But there have been several surprising results relative to predictions from models developed to identify monitoring needs and evaluate experimental design options at the start of the adaptive ecosystem assessment and management program in 1997

  2. Structure and mechanics of the San Andreas-San Gregorio fault junction, San Francisco, California

    Science.gov (United States)

    Parsons, Tom; Bruns, Terry R.; Sliter, Ray

    2005-01-01

    The right-lateral San Gregorio and San Andreas faults meet west of the Golden Gate near San Francisco. Coincident seismic reflection and refraction profiling across the San Gregorio and San Andreas faults south of their junction shows the crust between them to have formed shallow extensional basins that are dissected by parallel strike-slip faults. We employ a regional finite element model to investigate the long-term consequences of the fault geometry. Over the course of 2-3 m.y. of slip on the San Andreas-San Gregorio fault system, elongated extensional basins are predicted to form between the two faults. An additional consequence of the fault geometry is that the San Andreas fault is expected to have migrated eastward relative to the San Gregorio fault. We thus propose a model of eastward stepping right-lateral fault formation to explain the observed multiple fault strands and depositional basins. The current manifestation of this process might be the observed transfer of slip from the San Andreas fault east to the Golden Gate fault.

  3. 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.

  4. Eocene activity on the Western Sierra Fault System and its role incising Kings Canyon, California

    Science.gov (United States)

    Sousa, Francis J.; Farley, Kenneth A.; Saleeby, Jason; Clark, Marin

    2016-04-01

    Combining new and published apatite (U-Th)/He and apatite 4He/3He data from along the Kings River canyon, California we rediscover a west-down normal fault on the western slope of the southern Sierra Nevada, one of a series of scarps initially described by Hake (1928) which we call the Western Sierra Fault System. Integrating field observations with apatite (U-Th)/He data, we infer a single fault trace 30 km long, and constrain the vertical offset across this fault to be roughly a kilometer. Thermal modeling of apatite 4He/3He data documents a pulse of footwall cooling near the fault and upstream in the footwall at circa 45-40 Ma, which we infer to be the timing of a kilometer-scale incision pulse resulting from the fault activity. In the context of published data from the subsurface of the Sacramento and San Joaquin Valleys, our data from the Western Sierra Fault System suggests an Eocene tectonic regime dominated by low-to-moderate magnitude extension, surface uplift, and internal structural deformation of the southern Sierra Nevada and proximal Great Valley forearc.

  5. 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.

  6. Grand Canyon Trekkers: School-Based Lunchtime Walking Program

    Science.gov (United States)

    Hawthorne, Alisa; Shaibi, Gabriel; Gance-Cleveland, Bonnie; McFall, Sarah

    2011-01-01

    The incidence of childhood overweight is especially troubling among low income Latino youth. Grand Canyon Trekkers (GCT) was implemented as a quasi-experimental study in 10 Title 1 elementary schools with a large Latino population to examine the effects of a 16-week structured walking program on components of health-related physical fitness: Body…

  7. College of the Canyons Nursing Alumni Surveys, Spring 2001. Report.

    Science.gov (United States)

    Meuschke, Daylene M; Dixon, P. Scott; Gribbons, Barry C.

    In the summer of 2001, College of the Canyons (California) conducted of study of registered nursing (RN) and licensed vocational nursing (LVN) alumni, as well as their employers, to assess satisfaction with the preparation and training they received through the College's nursing programs. Out of the 89 invited nursing alumni, 33 surveys were…

  8. 78 FR 60693 - Establishment of the Ballard Canyon Viticultural Area

    Science.gov (United States)

    2013-10-02

    ... duties in the administration and enforcement of this law. Part 4 of the TTB regulations (27 CFR part 4... adequate information as to the identity and quality of the product. The Alcohol and Tobacco Tax and Trade... professional'' who is familiar with wines produced in the Ballard Canyon area. None of the comments...

  9. 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.

  10. Effects of electric vehicles on air quality in street canyons

    Directory of Open Access Journals (Sweden)

    Tilmann Schöllnhammer

    2014-09-01

    Full Text Available Road traffic is one of the main causes of poor air quality in European cities. Electric vehicles (EV are often presented as climate friendly and as a solution for air quality problems in cities. The aim of this study is to investigate how much of this claim is true and to find out the necessary shares of electric vehicles of different types needed to solve air quality problems in street canyons. For example, the German government has formulated the ambitious goal of increasing the amount of electric vehicles in Germany to 1 million in 2020 and 6 million in 2030. Will this improve the air quality significantly? The focus of the present study is the air quality in street canyons, with a focus on PM10 and NO2 concentrations. We concentrate our investigation on road traffic, taking the fleet composition into account. A sensitivity study with a dispersion model was carried out for two street canyons in North Rhine-Westphalia, typical for moderately polluted street canyons in European cities. It is shown that the reduction potential is larger for NO2 than for PM10. The necessary share of electric vehicles to comply with the limit values lies at about 40 % for NO2 and 100 % for PM10, respectively. Thus, the share of electric vehicles needed to comply with the limit values is far above the goal of the German government.

  11. San Cástulo

    OpenAIRE

    Jaramillo, Tania

    2014-01-01

    Porque no te acercas y nos entendemos, nos vamos cayendo por el lucro de la colonia, nos perdemos en la esquina de san Cástulo y nos vamos volando a Eleuterio, en una noche, que la luna nos vigile, que nos aguarde, que retrase el día, y la gente permanezca dormida o despierta pero temerosa de la noche, de los policías y los delincuentes, de los violadores y de nosotros, de la vida nocturna, de ese lugar oscuro en alguna parte, donde nos convertimos y aullamos.

  12. San Cástulo

    OpenAIRE

    Jaramillo, Tania

    2014-01-01

    Porque no te acercas y nos entendemos, nos vamos cayendo por el lucro de la colonia, nos perdemos en la esquina de san Cástulo y nos vamos volando a Eleuterio, en una noche, que la luna nos vigile, que nos aguarde, que retrase el día, y la gente permanezca dormida o despierta pero temerosa de la noche, de los policías y los delincuentes, de los violadores y de nosotros, de la vida nocturna, de ese lugar oscuro en alguna parte, donde nos convertimos y aullamos.

  13. Coma blisters sans coma.

    Science.gov (United States)

    Heinisch, Silke; Loosemore, Michael; Cusack, Carrie A; Allen, Herbert B

    2012-09-01

    Coma blisters (CBs) are self-limited lesions that occur in regions of pressure during unconscious states classically induced by barbiturates. We report a case of CBs sans coma that were histologically confirmed in a 41-year-old woman who developed multiple tense abdominal bullae with surrounding erythema following a transatlantic flight. Interestingly, the patient was fully conscious and denied medication use or history of medical conditions. A clinical diagnosis of CBs was confirmed by histopathologic findings of eccrine gland necrosis, a hallmark of these bulIous lesions.

  14. 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

  15. San Diego's Capital Planning Process

    Science.gov (United States)

    Lytton, Michael

    2009-01-01

    This article describes San Diego's capital planning process. As part of its capital planning process, the San Diego Unified School District has developed a systematic analysis of functional quality at each of its school sites. The advantage of this approach is that it seeks to develop and apply quantifiable metrics and standards for the more…

  16. Los Angeles og San Francisco

    DEFF Research Database (Denmark)

    Ørstrup, Finn Rude

    1998-01-01

    Kompendium udarbejdet til en studierejse til Los Angeles og San Francisco april-maj 1998 Kunstakademiets Arkitektskole, Institut 3H......Kompendium udarbejdet til en studierejse til Los Angeles og San Francisco april-maj 1998 Kunstakademiets Arkitektskole, Institut 3H...

  17. Tidal motions and tidally induced fluxes through La Línea submarine canyon, western Alboran Sea

    Science.gov (United States)

    Lafuente, Jesús GarcíA.; Sarhan, Tarek; Vargas, Manuel; Vargas, Juan M.; Plaza, Francisco

    1999-02-01

    Detailed observations from two mooring lines deployed in La Línea submarine canyon, western Alboran Sea, are presented. This is a narrow canyon in the sense that its width is always less than the internal radius of deformation. Tidal currents within the canyon are polarized in the along-canyon direction according to its narrow nature. They have considerable amplitude (values of around 0.5 m/s are often observed) and are forced by the internal pressure gradients associated with the baroclinic tide that is generated in the surroundings. Subsequent amplification of onshore baroclinic currents within the canyon accounts for the large amplitude observed. Cross-shelf exchange through the canyon due to tidal motions is different from zero despite the close to zero mean of tidal currents. The explanation is based on the asymmetry of water properties flowing up-canyon and down-canyon (some sort of tidal rectification). Regarding the energy flux, the canyon seems to be an adequate conduit to carry energy to the shore. Estimations made from our observations indicate that energy input onto the shelf per unit length parallel to the shore at the canyon head is enough to maintain mixing on the shelf at intermediate depths.

  18. Canyon formation constraints on the discharge of catastrophic outburst floods of Earth and Mars

    Science.gov (United States)

    Lapotre, Mathieu G. A.; Lamb, Michael P.; Williams, Rebecca M. E.

    2016-07-01

    Catastrophic outburst floods carved amphitheater-headed canyons on Earth and Mars, and the steep headwalls of these canyons suggest that some formed by upstream headwall propagation through waterfall erosion processes. Because topography evolves in concert with water flow during canyon erosion, we suggest that bedrock canyon morphology preserves hydraulic information about canyon-forming floods. In particular, we propose that for a canyon to form with a roughly uniform width by upstream headwall retreat, erosion must occur around the canyon head, but not along the sidewalls, such that canyon width is related to flood discharge. We develop a new theory for bedrock canyon formation by megafloods based on flow convergence of large outburst floods toward a horseshoe-shaped waterfall. The model is developed for waterfall erosion by rock toppling, a candidate erosion mechanism in well fractured rock, like columnar basalt. We apply the model to 14 terrestrial (Channeled Scablands, Washington; Snake River Plain, Idaho; and Ásbyrgi canyon, Iceland) and nine Martian (near Ares Vallis and Echus Chasma) bedrock canyons and show that predicted flood discharges are nearly 3 orders of magnitude less than previously estimated, and predicted flood durations are longer than previously estimated, from less than a day to a few months. Results also show a positive correlation between flood discharge per unit width and canyon width, which supports our hypothesis that canyon width is set in part by flood discharge. Despite lower discharges than previously estimated, the flood volumes remain large enough for individual outburst floods to have perturbed the global hydrology of Mars.

  19. Submarine canyon development in the Izu-Bonin forearc: A SeaMARC II and seismic survey of Aoga Shima Canyon

    Science.gov (United States)

    Klaus, Adam; Taylor, Brian

    1991-05-01

    SeaMARC II sidescan (imagery and bathymetry) and seismic data reveal the morphology, sedimentary processes, and structural controls on submarine canyon development in the central Izu-Bonin forearc, south of Japan. Canyons extend up to 150 km across the forearc from the trench-slope break to the active volcanic arc. The canyons are most deeply incised (1200 1700 m) into the gentle gradients (1 2°) upslope on the outer arc high (OAH) and lose bathymetric expression on the steep (6 18°) inner trench-slope. The drainage patterns indicate that canyons are formed by both headward erosion and downcutting. Headward erosion proceeds on two scales. Initially, pervasive small-scale mass wasting creates curvilinear channels and pinnate drainage patterns. Large-scale slumping, evidenced by abundant crescent-shaped scarps along the walls and tributaries of Aoga Shima Canyon, occurs only after a channel is present, and provides a mechanism for canyon branching. The largest slump has removed >16 km3 of sediment from an ˜85 km2 area of seafloor bounded by scarps more than 200 m high and may be in the initial stages of forming a new canyon branch. The northern branch of Aoga Shima Canyon has eroded upslope to the flanks of the arc volcanoes allowing direct tapping of this volcaniclastic sediment source. Headward erosion of the southern branch is not as advanced but the canyon may capture sediments supplied by unconfined (non-channelized) mass flows. Oligocene forearc sedimentary processes were dominated by unconfined mass flows that created sub-parallel and continuous sedimentary sequences. Pervasive channel cut-and-fill is limited to the Neogene forearc sedimentary sequences which are characterized by migrating and unconformable seismic sequences. Extensive canyon formation permitting sediment bypassing of the forearc by canyon-confined mass flows began in the early Miocene after the basin was filled to the spill points of the OAH. Structural lows in the OAH determined the

  20. Recent faulting in the Gulf of Santa Catalina: San Diego to Dana Point

    Science.gov (United States)

    Ryan, H.F.; Legg, M.R.; Conrad, J.E.; Sliter, R.W.

    2009-01-01

    We interpret seismic-reflection profiles to determine the location and offset mode of Quaternary offshore faults beneath the Gulf of Santa Catalina in the inner California Continental Borderland. These faults are primarily northwest-trending, right-lateral, strike-slip faults, and are in the offshore Rose Canyon-Newport-Inglewood, Coronado Bank, Palos Verdes, and San Diego Trough fault zones. In addition we describe a suite of faults imaged at the base of the continental slope between Dana Point and Del Mar, California. Our new interpretations are based on high-resolution, multichannel seismic (MCS), as well as very high resolution Huntec and GeoPulse seismic-reflection profiles collected by the U.S. Geological Survey from 1998 to 2000 and MCS data collected by WesternGeco in 1975 and 1981, which have recently been made publicly available. Between La Jolla and Newport Beach, California, the Rose Canyon and Newport-Inglewood fault zones are multistranded and generally underlie the shelf break. The Rose Canyon fault zone has a more northerly strike; a left bend in the fault zone is required to connect with the Newport-Inglewood fault zone. A prominent active anticline at mid-slope depths (300-400 m) is imaged seaward of where the Rose Canyon fault zone merges with the Newport-Inglewood fault zone. The Coronado Bank fault zone is a steeply dipping, northwest-trending zone consisting of multiple strands that are imaged from south of the U.S.-Mexico border to offshore of San Mateo Point. South of the La Jolla fan valley, the Coronado Bank fault zone is primarily transtensional; this section of the fault zone ends at the La Jolla fan valley in a series of horsetail splays. The northern section of the Coronado Bank fault zone is less well developed. North of the La Jolla fan valley, the Coronado Bank fault zone forms a positive flower structure that can be mapped at least as far north as Oceanside, a distance of ??35 km. However, north of Oceanside, the Coronado Bank

  1. 78 FR 39610 - Safety Zone; Big Bay Boom, San Diego Bay; San Diego, CA

    Science.gov (United States)

    2013-07-02

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Big Bay Boom, San Diego Bay; San Diego, CA... temporary safety zones upon the navigable waters of the San Diego Bay for the annual Port of San Diego... Sector San Diego, Coast Guard; telephone 619-278-7261, email d11marineeventssd@uscg.mil . If you have...

  2. 75 FR 38412 - Safety Zone; San Diego POPS Fireworks, San Diego, CA

    Science.gov (United States)

    2010-07-02

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Diego POPS Fireworks, San Diego, CA... zone on the ] navigable waters of San Diego Bay in support of the San Diego POPS Fireworks. This safety.... Coast Guard Sector San Diego, CA; telephone 619-278- 7262, e-mail Shane.E.Jackson@uscg.mil . If you have...

  3. 78 FR 42027 - Safety Zone; San Diego Bayfair; Mission Bay, San Diego, CA

    Science.gov (United States)

    2013-07-15

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Diego Bayfair; Mission Bay, San Diego... proposing a temporary safety zone on the navigable waters of Mission Bay in San Diego, CA for the San Diego..., call or email Lieutenant John Bannon, Waterways Management, U.S. Coast Guard Sector San Diego...

  4. 78 FR 29289 - Safety Zone; Big Bay Boom, San Diego Bay, San Diego, CA

    Science.gov (United States)

    2013-05-20

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Big Bay Boom, San Diego Bay, San Diego, CA... establish four temporary safety zones upon the navigable waters of San Diego ] Bay for the Port of San Diego... Management, U.S. Coast Guard Sector San Diego; telephone (619) 278-7261, email John.E.Bannon@uscg.mil . If...

  5. 78 FR 53245 - Safety Zone; San Diego Bayfair; Mission Bay, San Diego, CA

    Science.gov (United States)

    2013-08-29

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Diego Bayfair; Mission Bay, San Diego... temporary safety zone upon the navigable waters of Mission Bay in San Diego, CA for the annual San Diego... Management, U.S. Coast Guard Sector San Diego; telephone (619) 278-7261, email John.E.Bannon@uscg.mil . If...

  6. Numerical Study of Urban Canyon Microclimate Related to Geometrical Parameters

    Directory of Open Access Journals (Sweden)

    Andrea de Lieto Vollaro

    2014-11-01

    Full Text Available In this study a microclimate analysis on a particular urban configuration: the—street canyon—has been carried out. The analysis, conducted by performing numerical simulations using the finite volumes commercial code ANSYS-Fluent, shows the flow field in an urban environment, taking into account three different aspect ratios (H/W. This analysis can be helpful in the study on urban microclimate and on the heat exchanges with the buildings. Fluid-dynamic fields on vertical planes within the canyon, have been evaluated. The results show the importance of the geometrical configuration, in relation to the ratio between the height (H of the buildings and the width (W of the road. This is a very important subject from the point of view of “Smart Cities”, considering the urban canyon as a subsystem of a larger one (the city, which is affected by climate changes.

  7. 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.

  8. Apatite 4He/3He and (U-Th)/He evidence for an ancient Grand Canyon.

    Science.gov (United States)

    Flowers, R M; Farley, K A

    2012-12-21

    The Grand Canyon is one of the most dramatic features on Earth, yet when and why it was carved have been controversial topics for more than 150 years. Here, we present apatite (4)He/(3)He thermochronometry data from the Grand Canyon basement that tightly constrain the near-surface cooling history associated with canyon incision. (4)He/(3)He spectra for eastern Grand Canyon apatites of differing He date, radiation damage, and U-Th zonation yield a self-consistent cooling history that substantially validates the He diffusion kinetic model applied here. Similar data for the western Grand Canyon provide evidence that it was excavated to within a few hundred meters of modern depths by ~70 million years ago (Ma), in contrast to the conventional model in which the entire canyon was carved since 5 to 6 Ma.

  9. 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.

  10. Los Alamos Canyon Ice Rink Parking Flood Plain Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Hathcock, Charles Dean [Los Alamos National Lab. (LANL), Los Alamos, NM (United States; Keller, David Charles [Los Alamos National Lab. (LANL), Los Alamos, NM (United States

    2015-02-10

    The project location is in Los Alamos Canyon east of the ice rink facility at the intersection of West and Omega roads (Figure 1). Forty eight parking spaces will be constructed on the north and south side of Omega Road, and a lighted walking path will be constructed to the ice rink. Some trees will be removed during this action. A guardrail of approximately 400 feet will be constructed along the north side of West Road to prevent unsafe parking in that area.

  11. Outbreak of leptospirosis among canyoning participants, Martinique, 2011.

    OpenAIRE

    Hochedez, Patrick; Escher, M.; Decoussy, H.; Pasgrimaud, L.; R. Martinez; Rosine, J.; Théodose, R.; Bourhy,Pascale; Picardeau, Mathieu; Olive, C.; Ledrans, M.; Cabie, André

    2013-01-01

    International audience; Two gendarmes who participated in canyoning activities on 27 June 2011 on the Caribbean island of Martinique were diagnosed with leptospirosis using quantitative real-time polymerase chain reaction (qPCR), 9 and 12 days after the event. Among the 45 participants who were contacted, 41 returned a completed questionnaire, of whom eight met the outbreak case definition. The eight cases sought medical attention and were given antibiotics within the first week after fever o...

  12. On subsurface cooling associated with the Biobio River Canyon (Chile)

    Science.gov (United States)

    Sobarzo, Marcus; Saldías, Gonzalo S.; Tapia, Fabian J.; Bravo, Luis; Moffat, Carlos; Largier, John L.

    2016-07-01

    Submarine canyons cutting across the continental shelf can modulate the cross-shelf circulation being effective pathways to bring water from the deep ocean onto the shelf. Here, we use 69 days of moored array observations of temperature and ocean currents collected during the spring of 2013 and winter-spring 2014, as well as shipboard hydrographic surveys and sea-level observations to characterize cold, oxygen poor, and nutrient-rich upwelling events along the Biobio Submarine Canyon (BbC). The BbC is located within the Gulf of Arauco at 36° 50'S in the Central Chilean Coast. The majority of subtidal temperature at 150 m depth is explained by subtidal variability in alongshore currents on the canyon with a lag of less than a day (r2 = 0.65). Using the vertical displacement of the 10° and 10.5°C isotherms, we identified nine upwelling events, lasting between 20 h to 4.5 days, that resulted in vertical isothermal displacements ranging from 29 to 137 m. The upwelled water likely originated below 200 m. Majority of the cooling events were related with strong northward (opposite Kelvin wave propagation) flow and low pressure at the coast. Most of these low pressure events occur during relatively weak local wind forcing conditions, and were instead related with Coastal Trapped Waves (CTWs) propagating southwards from lower latitudes. These cold, high-nutrient, low-oxygen waters may be further upwelled and advected into the Gulf of Arauco by wind forcing. Thus, canyon upwelling may be a key driver of biological productivity and oxygen conditions in this Gulf.

  13. 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.

  14. Riparian Habitat - San Joaquin River

    Data.gov (United States)

    California Department of Resources — The immediate focus of this study is to identify, describe and map the extent and diversity of riparian habitats found along the main stem of the San Joaquin River,...

  15. 1906 San Francisco, USA Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 1906 San Francisco earthquake was the largest event (magnitude 8.3) to occur in the conterminous United States in the 20th Century. Recent estimates indicate...

  16. Partly standing internal tides in a dendritic submarine canyon observed by an ocean glider

    Science.gov (United States)

    Hall, Rob A.; Aslam, Tahmeena; Huvenne, Veerle A. I.

    2017-08-01

    An autonomous ocean glider is used to make the first direct measurements of internal tides within Whittard Canyon, a large, dendritic submarine canyon system that incises the Celtic Sea continental slope and a site of high benthic biodiversity. This is the first time a glider has been used for targeted observations of internal tides in a submarine canyon. Vertical isopycnal displacement observations at different stations fit a one-dimensional model of partly standing semidiurnal internal tides - comprised of a major, incident wave propagating up the canyon limbs and a minor wave reflected back down-canyon by steep, supercritical bathymetry near the canyon heads. The up-canyon internal tide energy flux in the primary study limb decreases from 9.2 to 2.0 kW m-1 over 28 km (a dissipation rate of 1 - 2.5 ×10-7 Wkg-1), comparable to elevated energy fluxes and internal tide driven mixing measured in other canyon systems. Within Whittard Canyon, enhanced mixing is inferred from collapsed temperature-salinity curves and weakened dissolved oxygen concentration gradients near the canyon heads. It has previously been hypothesised that internal tides impact benthic fauna through elevated near-bottom current velocities and particle resuspension. In support of this, we infer order 20 cm s-1 near-bottom current velocities in the canyon and observe high concentrations of suspended particulate matter. The glider observations are also used to estimate a 1 °C temperature range and 12 μmol kg-1 dissolved oxygen concentration range, experienced twice a day by organisms on the canyon walls, due to the presence of internal tides. This study highlights how a well-designed glider mission, incorporating a series of tide-resolving stations at key locations, can be used to understand internal tide dynamics in a region of complex topography, a sampling strategy that is applicable to continental shelves and slopes worldwide.

  17. Three-Dimensional Scale-Model Tank Experiment of the Hudson Canyon Region

    Science.gov (United States)

    2014-09-30

    Three-Dimensional Scale-Model Tank Experiment of the Hudson Canyon Region Jason D. Sagers Applied Research Laboratories at The University of...planning for future experiments in ocean environments with slopes and canyons . APPROACH The development of fully 3D numerical acoustic propagation models...Experiment of the Hudson Canyon Region 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER

  18. Late Holocene earthquake history of the Brigham City segment of the Wasatch fault zone at the Hansen Canyon, Kotter Canyon, and Pearsons Canyon trench sites, Box Elder County, Utah

    Science.gov (United States)

    DuRoss, Christopher B.; Personius, Stephen F.; Crone, Anthony J.; McDonald, Greg N.; Briggs, Richard W.

    2012-01-01

    Of the five central segments of the Wasatch fault zone (WFZ) having evidence of recurrent Holocene surface-faulting earthquakes, the Brigham City segment (BCS) has the longest elapsed time since its most recent surface-faulting event (~2.1 kyr) compared to its mean recurrence time between events (~1.3 kyr). Thus, the BCS has the highest time-dependent earthquake probability of the central WFZ. We excavated trenches at three sites––the Kotter Canyon and Hansen Canyon sites on the north-central BCS and Pearsons Canyon site on the southern BCS––to determine whether a surface-faulting earthquake younger than 2.1 ka occurred on the BCS. Paleoseismic data for Hansen Canyon and Kotter Canyon confirm that the youngest earthquake on the north-central BCS occurred before 2 ka, consistent with previous north-central BCS investigations at Bowden Canyon and Box Elder Canyon. At Hansen Canyon, the most recent earthquake is constrained to 2.1–4.2 ka and had 0.6–2.5 m of vertical displacement. At Kotter Canyon, we found evidence for two events at 2.5 ± 0.3 ka and 3.5 ± 0.3 ka, with an average displacement per event of 1.9–2.3 m. Paleoseismic data from Pearsons Canyon, on the previously unstudied southern BCS, indicate that a post-2 ka earthquake ruptured this part of the segment. The Pearsons Canyon earthquake occurred at 1.2 ± 0.04 ka and had 0.1–0.8 m of vertical displacement, consistent with our observation of continuous, youthful scarps on the southern 9 km of the BCS having 1–2 m of late Holocene(?) surface offset. The 1.2-ka earthquake on the southern BCS likely represents rupture across the Weber–Brigham City segment boundary from the penultimate Weber-segment earthquake at about 1.1 ka. The Pearsons Canyon data result in a revised length of the BCS that has not ruptured since 2 ka (with time-dependent probability implications), and provide compelling evidence of at least one segment-boundary failure and multi-segment rupture on the central WFZ. Our

  19. 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

  20. Sand Wave Migrations Within Monterey Submarine Canyon, California

    Science.gov (United States)

    Xu, J.; Wong, F. L.

    2006-12-01

    Repeated high-resolution multi-beam surveys revealed the existence of a sand wave field along the axis of the Monterey submarine canyon between 20 and 300 m water depth. These sand waves range in wave length from 20 to 70 m and 2 to 5 m in height. Comparison of sequential multi-beam grid data (months apart) indicates that the sand waves apparently migrate upcanyon at some places while the same data clearly show that the sand waves migrate downcanyon at other locations. One hypothesis is that strong internal tidal flows, whose upcanyon component is intensified by the narrow canyon, are responsible for forming the sand wave field and for migrating the sand waves upcanyon. Another hypothesis is that the sand wave field is formed by creeping (analogous to the movement within glaciers), and in general they move in the downcanyon direction. A field experiment was conducted in 2005-06 to measure the driving forces (in hypothesis #1) that form and move the sand waves, and to collect the internal sedimentological structure within the sand waves that could reveal information on hypothesis #2. A mooring designed to measure near-floor velocity profiles, temperature, salinity, and sediment concentration in the water column was deployed for one year (June 2005 -July 2006) at 250 m water depth, slightly downcanyon of the sand wave field. In addition, a mapping survey was conducted in February, 2006 for collecting multi-beam and chirp profiles in the canyon head area of the sand wave field. Preliminary examination of the ADCP (downward looking) showed some very interesting features - the near- floor current dramatically changes with the spring-neap cycle of the surface tide. The time variation of the along-canyon current during neap tides - a sudden jump of upcanyon velocity before gradually tapering down, is typical of internal tides (internal bores). The time variation during spring tides when along canyon velocities reverse directions from upcanyon to downcanyon and gradually

  1. Environmental assessment : Rodent control program : San Joaquin river levee : San Luis National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Lower San Joaquin Levee District (LSJLD) requires that six miles of levee situated along the San Joaquin River on San Luis National Wildlife Refuge (SLNWR) be...

  2. Residencia San Pedro, California

    Directory of Open Access Journals (Sweden)

    Neutra, Richard J.

    1961-01-01

    Full Text Available Esta vivienda representa una aproximación más hacia la típica casa grande española, con techos de teca de 7 cm, que los señores Rados han edificado y en la que albergan a su gran familia de hijos, los cuales tienen ya sus propios vástagos. Ambos, el señor y la señora Rados, descienden de familias navieras italianas de Trieste, y el propio señor Rados tiene una compañía constructora de barcos en el puerto de San Pedro, que puede verse desde su propia casa. Los dos son verdaderamente unos abuelos muy sociables, cariñosos y atentos. Por añadidura, la señora Rados se entretiene frecuentemente y le agrada el cuidado de la casa. Por ello ha sido proyectada para facilitar sensiblemente toda esta serie de actividades.

  3. 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

  4. 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.

  5. [Pteridophytes that indicate environmental alteration in the temperate forest of San Jerónimo Amanalco, Texcoco, Mexico].

    Science.gov (United States)

    Lucía Rodríguez, Romero; Pacheco, Leticia; Zavala Hurtado, José Alejandro

    2008-06-01

    Pteridophytes that indicate environmental alteration in the San Jer6nimo Amanalco temperate forest, Texcoco, Mexico. The patterns of distribution of 26 pteridophyte species were studied as possible indicators of environmental alteration in the temperate forest of San Jer6nimo Amanalco, Texcoco, State of Mexico. The presence and abundance of the pteridoflora was studied in relation to edaphic, topographic and vegetation variables in 100 sampling locations within an area of 494 hectares. The relationship between these variables was studied using Canonical Correspondence Analysis. Five landscapes were recognized in the study zone according to the degree of deterioration: severe erosion, erosion, mountain with moderate reversible deterioration, mountain with no evident deterioration, and canyon with no evident deterioration. Cheilanthes bonariensis and Pellaea ternifolia are indicators of environmental degradation. The taxa that only grow in landscapes without apparent alteration are Adiantum andicola, Adiantum poiretii, Argyrochosma incana, Asplenium blepharophorum, Dryopteris pseudo filix-mas, Equisetum hyemale and Pteris cretica.

  6. Sequence stratigraphy of the marine and non-marine Upper Cretaceous Dakota Sandstone, San Juan Basin, USA

    Energy Technology Data Exchange (ETDEWEB)

    Johannessen, P.

    1994-12-31

    Late Cretaceous, middle Cenomanian, shallow marine and non-marine sandstones of the Dakota Sandstone have been studied in the western part of the Western Interior, San Juan Basin, New Mexico. 15-20 m thick sharp based, slightly coarsening upward shoreface sandstones characterize the eastern fully marine part of the San Juan Basin, while non-marine sediments dominate the western part of the basin. The aim of this paper is to carefully correlate key-surfaces from the thick shoreface sandstones towards the west into the non-marine succession, using sequence stratigraphic principles. The present paper will document an additional marine sandstone underlying the Cubero Tongue; the Oak Canyon Member. (au)

  7. 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.

  8. 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.

  9. 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)

  10. 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...

  11. Biological Resources Survey of Mountain Springs Canyon on the Naval Weapons Center.

    Science.gov (United States)

    1983-03-01

    Coleo - gyne association (Beatley, 1976) further up the canyon where the aspect of the north- facing slope changes from northwest to north near Mountain...argusensis) was collected in the upper half of the canyon. Although common in Coleo - j ne habitat, it is considered sensitive by BLM (1980) due to its endemic

  12. 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...

  13. 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...

  14. 75 FR 10308 - Fire Management Plan, Final Environmental Impact Statement, Record of Decision, Grand Canyon...

    Science.gov (United States)

    2010-03-05

    ... Doc No: 2010-4414] DEPARTMENT OF THE INTERIOR National Park Service Fire Management Plan, Final... Impact Statement for the Fire Management Plan, Grand Canyon National Park. SUMMARY: Pursuant to the... availability of the Record of Decision for the Fire Management Plan, Grand Canyon National Park, Arizona. On...

  15. Reconstructing the Aliso Canyon natural gas leak incident

    Science.gov (United States)

    Duren, R. M.; Yadav, V.; Verhulst, K. R.; Thorpe, A. K.; Hopkins, F. M.; Prasad, K.; Kuai, L.; Thompson, D. R.; Wong, C.; Sander, S. P.; Mueller, K. L.; Nehrkorn, T.; Lee, M.; Hulley, G. C.; Johnson, W. R.; Aubrey, A. D.; Whetstone, J. R.; Miller, C. E.

    2016-12-01

    Natural gas is a key energy source and presents significant policy challenges including energy reliability and the potential for fugitive methane emissions. The well blowout reported in October 2015 at the Aliso Canyon underground gas storage facility near Porter Ranch, California and subsequent uncontrolled venting was the largest single anthropogenic methane source known to date. Multiple independent estimates indicate that this super-emitter source rivaled the normal methane flux of the entire South Coast Air Basin (SoCAB) for several months until the well was plugged. The complexity of the event and logistical challenges - particularly in the initial weeks - presented significant barriers to estimating methane losses. Additionally, accounting for total gas lost is necessary but not sufficient for understanding the sequence of events and the controlling physical processes. We used a tiered system of observations to assess methane emissions from the Aliso Canyon incident. To generate a complete flux time-series, we applied tracer-transport models and tracer-tracer techniques to persistent, multi-year atmospheric methane observations from a network of surface in-situ and remote-sensing instruments. To study the fine spatio-temporal structure of methane plumes and understand the changing source morphology, we conducted intensive mobile surface campaigns, deployed airborne imaging spectrometers, requested special observations from two satellites, and employed large eddy simulations. Through a synthesis analysis we assessed methane fluxes from Aliso Canyon before, during and after the reported incident. We compared our fine scale spatial data with bottom-up data and reports of activity at the facility to better understand the controlling processes. We coordinated with California stakeholder agencies to validate and interpret these results and to consider the potential broader implications on underground gas storage and future priorities for methane monitoring.

  16. Geo-hazard by sediment mass movements in submarine canyons

    Science.gov (United States)

    Ghaith, Afif; Fakhri, Milad; Ivaldi, Roberta; Ciavola, Paolo

    2017-04-01

    Submarine mass movements and their consequences are of major concern for coastal communities and infrastructures but also for the exploitation and the development of seafloor resources. Elevated awareness of the need for better understanding of the underwater mass movement is coupled with great advances in underwater mapping technologies over the past two decades. The seafloor in the Nahr Ibrahim and Saida regions (Lebanon) is characterized by deep canyons, reaching one thousand meters depths in proximity of the coast. Signs of submarine mass movement instability related to these canyons create a connection between shallow and deep water. The presence of these canyons in a tectonically active area generates a particular drained mechanism to the sediment in form of mass movement and slumping. Identification of potential areas where slope movements could be triggered requires data with high spatial resolution. Since this area is poorly explored, in the framework of an international project between Lebanese Navy, Lebanese National Center for Marine Sciences, University of Ferrara and Italian Hydrographic Institute, we analyse the morpho-bathymetric and sedimentological characters of the coastal and shelf sectors. Multibeam echosounder and sub-bottom profiler acoustic systems calibrated with ground truths (sediment grab and core samples) allow us to characterize the nature of seafloor and sub-seafloor with particular detail to the geotechnical properties of sediments and high resolution seismic stratigraphy of the shallow layers. The detection of particular undersea features provides detail maps which are in support to littoral morpho-dynamics, coastal transport and sediment budget. Multilayer hydro-oceanographic map, referring to the seafloor dynamics in connection with deep water environment and drainage system, in accordance to the International Hydrographic Standards and nautical supports, are produced. This high resolution multibeam bathymetry dataset, integrated

  17. 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.

  18. 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.

  19. The benthic communities of the Cap de Creus canyon

    OpenAIRE

    2012-01-01

    The authors thank Fugro Survey, AOA Geophysics and the University of Barcelona for the multibeam bathymetry of the Cap de Creus canyon, the owners of the ROVs (FIELAX, INSTALSUB, Spain and Gavin Newman, UK), as well as the JAGO team (J. Schauer and K. Hissmann) from IFM-GEOMAR (Germany). We also thank the Spanish General Secretariat for the Sea (Ministerio de Agricultura, Alimentación y Medio Ambiente) for the vessel monitoring systems (VMS) data and the Fundación Biodiversidad for t...

  20. 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.

  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. Cold-water coral ecosystems in Cassidaigne Canyon: An assessment of their environmental living conditions

    Science.gov (United States)

    Fabri, M.-C.; Bargain, A.; Pairaud, I.; Pedel, L.; Taupier-Letage, I.

    2017-03-01

    The Cassidaigne canyon is one of the two canyons (together with Lacaze-Duthiers) of the French Mediterranean coast in which cold-water corals have settled and formed large colonies, providing a structural habitat for other species. Nevertheless, the communities settled in the Cassidaigne canyon are physically impacted by discharges of bauxite residues. New information on the distribution of the species Madrepora oculata and the associated species diversity in Cassidaigne canyon was provided by videos and photos acquired in 2013. An area investigated at 515 m depth harbored a high density of small colonies of M. oculata. The water column structure of the area was described by using a CTD transect deployed along the axis of the canyon. High resolution (10 m and 2 m) bathymetric data were collected in the Cassidaigne canyon in 2010 and 2014. Seafloor characteristics were derived from the 10 m resolution bathymetric data. Data on local hydrodynamic conditions in the first 10 m above the seafloor were produced by applying the MARS3D hydrodynamic model in the Cassidaigne canyon at a horizontal resolution of 80 m (CASCANS model configuration). These environmental datasets combined with the geographic coordinates of the known occurrences of dense M. oculata colonies in the canyon allowed establishing a model using the MaxEnt software package to predict the habitat distribution in terms of probability of occurrence. According to the water mass analysis, M. oculata habitats are mainly located in the layer of the Intermediate waters originating from the Eastern Mediterranean Basin. A high concentration of suspended sediment due to the bauxite residues expelled into the canyon was observed in the axis of the canyon where we measured 1 NTU (2.5 mg/l) at 100 m above the bottom while concentrations were even higher (2 NTU; 5 mg/l) closer to the bottom. The habitat suitability model indicates that the living conditions of M. oculata can be found in areas of the Cassidaigne canyon

  3. Vegetation - San Felipe Valley [ds172

    Data.gov (United States)

    California Department of Resources — This Vegetation Map of the San Felipe Valley Wildlife Area in San Diego County, California is based on vegetation samples collected in the field in 2002 and 2005 and...

  4. Morphology, origin and evolution of Pleistocene submarine canyons, New Jersey continental slope

    Science.gov (United States)

    Bhatnagar, T.; Mountain, G. S.

    2015-12-01

    Submarine canyons serve as important conduits for transport of detrital sediments from nearshore and shelf environments to adjacent deep marine basins. However, the processes controlling the formation, maintenance, and fill of these sediment pathways are complex. This study presents an investigation of these systems at the New Jersey continental margin using a grid of high-resolution, 48-channel seismic reflection data collected in 1995 on the R/V Oceanus cruise Oc270 as a part of the STRATAFORM initiative. The aim is to shed new light on the origin and role of submarine canyons in Pleistocene sedimentation beneath the outer shelf and upper continental slope. Preliminary investigation of the Pleistocene interval reveals prominent unconformities tied to and dated with published studies at 7 sites drilled by ODP Legs 150 and 174A. The profiles of the continental slope unveil a series of abandoned and now buried submarine canyons that have influenced the development of modern canyons. Mapping these systems has revealed a range of canyon geometries, including U, V-shaped and flat-bottomed cross sections, each suggesting different histories. At least three types of seismic facies constitute the canyon fills: parallel onlap, interpreted as infilling by alternating coarser turbidites and finer hemipelagic sediments, chaotic infill, signifying structureless, massive debris flow deposition, and lateral accretion infill by both turbidity and bottom currents. Canyon formation and development appear to be strongly influenced by variations in sediment supply, grain size, and currents on the continental slope. One goal of our research is to establish if the canyons were initiated by failures at the base of the slope followed by upslope erosion, or by erosion at the shelf slope transition, and then downslope extension by erosive events. No single model accounts for all canyons. The history of these canyons may elucidate the extent to which the shelf was exposed during sea

  5. 75 FR 39166 - Safety Zone; San Francisco Giants Baseball Game Promotion, San Francisco, CA

    Science.gov (United States)

    2010-07-08

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Francisco Giants Baseball Game... Bay off San Francisco, CA in support of the San Francisco Giants Baseball Game Promotion. This safety... Giants will sponsor the San Francisco Giants Baseball Game Promotion on July 16, 2010, on the...

  6. 78 FR 21403 - Notice of Inventory Completion: San Francisco State University NAGPRA Program, San Francisco, CA

    Science.gov (United States)

    2013-04-10

    ... NAGPRA Program, c/o Department of Anthropology, San Francisco State University, 1600 Holloway Avenue, San...: Pursuant to 25 U.S.C. 3001(9), the human remains described in this notice represent the physical remains of... NAGPRA Program, c/o Department of Anthropology, San Francisco State University, 1600 Holloway Avenue, San...

  7. 76 FR 55796 - Safety Zone; TriRock Triathlon, San Diego Bay, San Diego, CA

    Science.gov (United States)

    2011-09-09

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; TriRock Triathlon, San Diego Bay, San Diego.... Basis and Purpose Competitor Group is sponsoring the TriRock Triathlon, consisting of 2000 swimmers....T11-431 Safety Zone; TriRock Triathlon, San Diego Bay, San Diego, CA. (a) Location. The limits of...

  8. 76 FR 45693 - Safety Zone; San Diego POPS Fireworks, San Diego, CA

    Science.gov (United States)

    2011-08-01

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Diego POPS Fireworks, San Diego, CA... temporary safety zone on the navigable waters of San Diego Bay in support of the San Diego POPS Fireworks... Diego, CA; telephone (619) 278- 7262, e-mail Shane.E.Jakcson@uscg.mil . If you have questions on viewing...

  9. 78 FR 38584 - Safety Zone; San Diego Symphony Summer POPS Fireworks 2013 Season, San Diego, CA

    Science.gov (United States)

    2013-06-27

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Diego Symphony Summer POPS Fireworks 2013 Season, San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a safety zone on the navigable waters of San Diego Bay in support of the San Diego...

  10. 76 FR 75908 - Notice of Inventory Completion: The University of California, San Diego, San Diego, CA

    Science.gov (United States)

    2011-12-05

    ... National Park Service Notice of Inventory Completion: The University of California, San Diego, San Diego... California on behalf of the University of California, San Diego, have completed an inventory of human remains... contact the University of California, San Diego. Disposition of the human remains and associated funerary...

  11. 77 FR 42647 - Safety Zone: San Diego Symphony POPS Fireworks; San Diego, CA

    Science.gov (United States)

    2012-07-20

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone: San Diego Symphony POPS Fireworks; San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a safety zone on the navigable waters of San Diego Bay in support of the San Diego Symphony POPS...

  12. 75 FR 77756 - Safety Zone; San Diego Parade of Lights Fireworks, San Diego, CA

    Science.gov (United States)

    2010-12-14

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Diego Parade of Lights Fireworks, San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a safety zone upon the navigable water of the San Diego Bay in San Diego, CA in support of the two...

  13. The San Bernabe power substation; La subestacion San Bernabe

    Energy Technology Data Exchange (ETDEWEB)

    Chavez Sanudo, Andres D. [Luz y Fuerza del Centro, Mexico, D. F. (Mexico)

    1997-12-31

    The first planning studies that gave rise to the San Bernabe substation go back to year 1985. The main circumstance that supports this decision is the gradual restriction for electric power generation that has been suffering the Miguel Aleman Hydro System, until its complete disappearance, to give priority to the potable water supply through the Cutzamala pumping system, that feeds in an important way Mexico City and the State of Mexico. In this document the author describes the construction project of the San Bernabe Substation; mention is made of the technological experiences obtained during the construction and its geographical location is shown, as well as the one line diagram of the same [Espanol] Los primeros estudios de planeacion que dieron origen a la subestacion San Bernabe se remontan al ano de 1985. La circunstancia principal que soporta esta decision es la restriccion paulatina para generar energia que ha venido experimentando el Sistema Hidroelectrico Miguel Aleman, hasta su desaparicion total, para dar prioridad al suministro de agua potable por medio del sistema de bombeo Cutzamala, que alimenta en forma importante a la Ciudad de Mexico y al Estado de Mexico. En este documento el autor describe el proyecto de construccion de la subestacion San Bernabe; se mencionan las experiencias tecnologicas obtenidas durante su construccion y se ilustra su ubicacion geografica, asi como un diagrama unifilar de la misma

  14. A Spanish Borderlands Community: San Antonio.

    Science.gov (United States)

    Teja, Jesus F. de la

    2000-01-01

    Discusses the founding of San Antonio, originally San Antonio de Bexar, which, in 1718, came into being as a military settlement involved in Spanish imperial defensive measures. Focuses on the development and continued growth of San Antonio, Texas's most populous city in the 19th century. (CMK)

  15. 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.

  16. Chemically traced blobs in the vicinity of a submarine canyon

    Science.gov (United States)

    Brogueira, M. J.; Cabeçadas, G.; Gonçalves, C.; Cabeçadas, P.

    2003-04-01

    A hydrographic cruise was carried out in May 2001 off southern Portugal, in the vicinity of Portimão canyon. This major topographic irregularity across the path of the Mediterranean undercurrent is known to induce water masses instability and to be a site of dipole formation. Two blobs of distinct water masses were revealed mainly through chemical tracers, namely dissolved oxygen and nutrients. One low-salinity blob, centred at ˜800 m depth, displayed high values of AOU (above 100 μmol/kg) and nutrients (NO_3 up to 14 μmol/kg, PO_4 up to 0.9 and Si(OH)_4 up to 11 μmol/kg), which are features of the Antarctic Intermediate Water (AAIW) present in the area. The deeper salty warm blob, extending from the MW outflow, corresponded to the relatively more oxygenated (AOU 77 μmol/kg) and nutrient-impoverished (NO_3 9 μmol/kg, PO_4 0.6 μmol/kg and Si(OH)_4 6 μmol/kg) saline Mediterranean Water. Further, the influence of this deeper blob expanding down (till 1800--2000 m) into the well-ventilated and nutrient-enriched North Atlantic Deep Water (NADW) was visible through nutrient patterns. The chemical data enabled the identification of the described blobs structure associated with this particular canyon located on the westward flow of MW into the North Atlantic.

  17. Trial by fire: underbalanced drilling for Horseshoe Canyon coals

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, K. [Nexen Inc., Calgary, AB (Canada)

    2008-07-01

    Four wells were drilled in August 2007 in the lower portion of Horseshoe Canyon. These wells were underbalanced and used air as the drilling fluid. The purpose was to establish the feasibility of under-reaming. This presentation discussed under balanced drilling for Horseshoe Canyon coals. It presented a review of the project and discussed the various project phases. Phase one involved under balanced drilling and under-reaming. The presentation of this phase addressed risk management; review of results; lessons learned; and recommended practices. An illustration of the risk management process was offered. This illustration included identification of hazards, categorization, evaluation, management, and communication. A risk matrix was also provided. Phase two was also presented which included a discussion of planning considerations; revised risk management; underbalanced redesign; and implementation. It was concluded that in order to eliminate the risk, oxygen must be removed or lowered to less than four per cent. It was also found that caution must be used when evaluating whether downhole conditions are in the explosive envelope. figs.

  18. 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.

  19. Bedrock aquifers of eastern San Juan County, Utah

    Science.gov (United States)

    Avery, Charles

    1986-01-01

    This study is one of a series of studies appraising the waterbearing properties of the Navajo Sandstone and associated formations in southern Utah.  The study area is about 4,600 square miles, extending from the Utah-Arizona State line northward to the San Juan-Grand County line and westward from the Utah-Colorado State line to the longitude of about 109°50'.Some of the water-yielding formations are grouped into aquifer systems. The C aquifer is comprised of the DeChelly Sandstone Member of the Cutler Formation.  The P aquifer is comprised of the Cedar Mesa Member of the Cutler Formation and the undifferentiated Cutler Formation. The N aquifer is comprised of the sedimentary section that includes the Wingate Sandstone, Kayenta Formation, Navajo Sandstone, Carmel Formation, and Entrada sandstone.  The M aquifer is comprised of the Bluff Sandstone Member and other sandstone units of the Morrison Formation.  The D aquifer is comprised of the Burro Canyon Formation and Dakota Sandstone.  Discharge from the ground-water reservoir to the San Juan River between gaging stations at Four Corners and Mexican Hat is about 66 cubic feet per second.The N aquifer is the main aquifer in the study area. Recharge by infiltration of precipitation is estimated to be 25,000 acre-feet per year.  A major ground-water divide exists under the broad area east of Monticello.  The thickness of the N aquifer, where the sedimentary section is fully preserved and saturated, generally is 750 to 1,250 feet.   Hydraulic conductivity values obtained from aquifer tests range from 0.02 to 0.34 foot per day.  The total volume of water in transient storage is about 11 million acre-feet. Well discharge somewhat exceeded 2,340 acre-feet during 1981.  Discharge to the San Juan River from the N aquifer is estimated to be 6.9 cubic feet per second. Water quality ranges from a calcium bicarbonate to sodium chloride type water

  20. Lung deposited surface area concentrations in a street canyon

    Science.gov (United States)

    Kuuluvainen, Heino; Hietikko, Riina; Järvinen, Anssi; Saukko, Erkka; Irjala, Matti; Niemi, Jarkko V.; Timonen, Hilkka; Keskinen, Jorma; Rönkkö, Topi

    2017-04-01

    Street canyons are interesting environments with respect to the dispersion of traffic emissions and human exposure. Pedestrians may be exposed to relatively high concentrations of fine particles and the vertical dispersion affects the human exposure above the ground level in buildings. Previously, particle concentrations have been measured in street canyons at a few different heights (Marini et al., 2015). The information on the lung deposited surface area (LDSA) concentration, which is a relevant metric for the negative health effects, is very limited even at the ground level of street canyons (Kuuluvainen et al., 2016). More information especially on the vertical dispersion and the ground level concentrations is needed, for instance, for the use of urban planning and the design of ventilation systems in buildings. Measurements were carried out in a busy street canyon in Helsinki, Finland, at an urban super-site measurement station (Mäkelänkatu 50). The data included vertical concentration profiles measured in an intensive measurement campaign with a Partector (Naneos GmbH) installed into a drone, long-term measurements with an AQ Urban particle sensor (Pegasor Ltd.), and an extensive comparison measurement in the field with different devices measuring the LDSA. These devices were an AQ Urban, Partector, DiSCmini (Testo AG), NSAM (TSI Inc.), and an ELPI+ (Dekati Ltd.). In addition, continuous measurements of gas phase components, particle size distributions, and meteorology were run at the supersite. The vertical profile measurements were con-ducted in November 2016 during two days. In the measurements, the drone was flown from the ground level to an altitude of 50 or 100 m, which is clearly above the roof level of the buildings. Altogether, 48 up-and-down flights were conducted during the two days. The vertical profiles were supported by continuous measurements at the ground level on both sides of the street canyon. The long-term measurements were conducted

  1. 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

  2. Mass movements in small canyons in the northeast of Baiyun deepwater area, north of the South China Sea

    Institute of Scientific and Technical Information of China (English)

    LI Xishuang; LIU Lejun; LI Jiagang; GAO Shan; ZHOU Qingjie; SU Tianyun

    2015-01-01

    The process of mass movements and their consequent turbidity currents in large submarine canyons has been widely reported, however, little attention was paid to that in small canyons. In this paper, we document mass movements in small submarine canyons in the northeast of Baiyun deepwater area, north of the South China Sea (SCS), and their strong effects on the evolution of the canyons based on geophysical data. Submarine canyons in the study area arrange closely below the shelf break zone which was at the depth of –500 m. Within submarine canyons, seabed surface was covered with amounts of failure scars resulted from past small-sized landslides. A complex process of mass transportation in the canyons is indicated by three directions of mass movements. Recent mass movement deposits in the canyons exhibit translucent reflections or parallel reflections which represent the brittle deformation and the plastic deformation, respectively. The area of most landslides in the canyons is less than 3 km2. The trigger mechanisms for mass movements in the study area are gravitational overloading, slope angle and weak properties of soil. Geophysical data indicate that the genesis of submarine canyons is the erosion of mass movements and consequent turbidity currents. The significant effects of mass movements on canyon are incision and sediment transportation at the erosion phases and fillings supply at the fill phases. This research will be helpful for the geological risk assessments and understanding the sediment transportation in the northern margin of the SCS.

  3. Telegraph Canyon Creek, City of Chula Vista, San Diego County, California. Detailed Report for Flood Control. Volume 2. Technical Appendixes.

    Science.gov (United States)

    1983-07-01

    canaliculata Mantis shrimp aguilla oolita MOLLUSKS Banded cockle Chione californiensis Smooth cockle Chione fluctifrga Wavy cockle Chione undatella...Transparent shrimp Spirontocaris paldiol Grass shrimp Hiopolyte californven31s Ghost shrimp Callianasso californiensis Crangonid shrimp Processa

  4. Preliminary Image Map of the 2007 Ammo Fire Perimeter, Las Pulgas Canyon Quadrangle, San Diego County, California

    Science.gov (United States)

    Clark, Perry S.; Scratch, Wendy S.; Bias, Gaylord W.; Stander, Gregory B.; Sexton, Jenne L.; Krawczak, Bridgette J.

    2008-01-01

    In the fall of 2007, wildfires burned out of control in southern California. The extent of these fires encompassed large geographic areas that included a variety of landscapes from urban to wilderness. The U.S. Geological Survey National Geospatial Technical Operations Center (NGTOC) is currently (2008) developing a quadrangle-based 1:24,000-scale image map product. One of the concepts behind the image map product is to provide an updated map in electronic format to assist with emergency response. This image map is one of 55 preliminary image map quadrangles covering the areas burned by the southern California wildfires. Each map is a layered, geo-registered Portable Document Format (.pdf) file. For more information about the layered geo-registered .pdf, see the readme file (http://pubs.usgs.gov/of/2008/1029/downloads/CA_Agua_Dulce_of2008-1029_README.txt). To view the areas affected and the quadrangles mapped in this preliminary project, see the map index (http://pubs.usgs.gov/of/2008/1029/downloads/CA_of2008_1029-1083_index.pdf) provided with this report.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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)

  10. Modern landscape processes affecting archaeological sites along the Colorado River corridor downstream of Glen Canyon Dam, Glen Canyon National Recreation Area, Arizona

    Science.gov (United States)

    East, Amy E.; Sankey, Joel B.; Fairley, Helen C.; Caster, Joshua J.; Kasprak, Alan

    2017-08-29

    The landscape of the Colorado River through Glen Canyon National Recreation Area formed over many thousands of years and was modified substantially after the completion of Glen Canyon Dam in 1963. Changes to river flow, sediment supply, channel base level, lateral extent of sedimentary terraces, and vegetation in the post-dam era have modified the river-corridor landscape and have altered the effects of geologic processes that continue to shape the landscape and its cultural resources. The Glen Canyon reach of the Colorado River downstream of Glen Canyon Dam hosts many archaeological sites that are prone to erosion in this changing landscape. This study uses field evaluations from 2016 and aerial photographs from 1952, 1973, 1984, and 1996 to characterize changes in potential windblown sand supply and drainage configuration that have occurred over more than six decades at 54 archaeological sites in Glen Canyon and uppermost Marble Canyon. To assess landscape change at these sites, we use two complementary geomorphic classification systems. The first evaluates the potential for aeolian (windblown) transport of river-derived sand from the active river channel to higher elevation archaeological sites. The second identifies whether rills, gullies, or arroyos (that is, overland drainages that erode the ground surface) exist at the archaeological sites as well as the geomorphic surface, and therefore the relative base level, to which those flow paths drain. Results of these assessments are intended to aid in the management of irreplaceable archaeological resources by the National Park Service and stakeholders of the Glen Canyon Dam Adaptive Management Program.

  11. Submarine canyons as the preferred habitat for wood-boring species of Xylophaga (Mollusca, Bivalvia)

    Science.gov (United States)

    Romano, C.; Voight, J. R.; Company, J. B.; Plyuscheva, M.; Martin, D.

    2013-11-01

    Submarine canyons are often viewed as natural “debris concentrators” on the seafloor. Organic substrates may be more abundant inside than outside canyon walls. To determine the effects of the presence these substrates in the Blanes submarine canyon (NW Mediterranean) and its adjacent western open slope, we deployed wood to study colonizing organisms. Three replicate pine and oak cubes (i.e. most common trees inland) were moored at 900, 1200, 1500 and 1800 m depth and collected after 3, 9 and 12 months. Wood from inside the canyon was significantly more heavily colonized by the five morphotypes of wood-boring bivalves than was wood on the adjacent open slope. Xylophaga sp. A dominated all wood types and locations, with peak abundance at 900 and 1200 m depth. Its growth rate was highest (0.070 mm d-1) during the first three months and was faster (or it recruits earlier) in pine than in oak. Size distribution showed that several recruitment events may have occurred from summer to winter. Xylophaga sp. B, appeared first after 9 months and clearly preferred pine over oak. As the immersion time was the same, this strongly supported a specific association between recruiters and type of substrate. Three morphotypes, pooled as Xylophaga spp. C, were rare and seemed to colonize preferentially oak inside the canyon and pine in the adjacent open slope. Individuals of Xylophaga were more abundant inside the canyon than in nearby off-canyon locations. Blanes Canyon may serve as a long-term concentrator of land-derived vegetal fragments and as a consequence sustain more animals. Are the species richness and abundance of wood-boring bivalves higher inside the canyon than on the adjacent open slope? Do the composition and density of the wood-boring bivalves change with deployment time and depth, as well as on the type of the sunken wood? What is the growth rate of the dominant wood-boring species?

  12. 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.

  13. Fish Passage Assessment: Big Canyon Creek Watershed, Technical Report 2004.

    Energy Technology Data Exchange (ETDEWEB)

    Christian, Richard

    2004-02-01

    This report presents the results of the fish passage assessment as outlined as part of the Protect and Restore the Big Canyon Creek Watershed project as detailed in the CY2003 Statement of Work (SOW). As part of the Northwest Power Planning Council's Columbia Basin Fish and Wildlife Program (FWP), this project is one of Bonneville Power Administration's (BPA) many efforts at off-site mitigation for damage to salmon and steelhead runs, their migration, and wildlife habitat caused by the construction and operation of federal hydroelectric dams on the Columbia River and its tributaries. The proposed restoration activities within the Big Canyon Creek watershed follow the watershed restoration approach mandated by the Fisheries and Watershed Program. Nez Perce Tribal Fisheries/Watershed Program vision focuses on protecting, restoring, and enhancing watersheds and treaty resources within the ceded territory of the Nez Perce Tribe under the Treaty of 1855 with the United States Federal Government. The program uses a holistic approach, which encompasses entire watersheds, ridge top to ridge top, emphasizing all cultural aspects. We strive toward maximizing historic ecosystem productive health, for the restoration of anadromous and resident fish populations. The Nez Perce Tribal Fisheries/Watershed Program (NPTFWP) sponsors the Protect and Restore the Big Canyon Creek Watershed project. The NPTFWP has the authority to allocate funds under the provisions set forth in their contract with BPA. In the state of Idaho vast numbers of relatively small obstructions, such as road culverts, block thousands of miles of habitat suitable for a variety of fish species. To date, most agencies and land managers have not had sufficient, quantifiable data to adequately address these barrier sites. The ultimate objective of this comprehensive inventory and assessment was to identify all barrier crossings within the watershed. The barriers were then prioritized according to the

  14. 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.

  15. 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.

  16. New High-Resolution 3D Seismic Imagery of Deformation and Fault Architecture Along Newport-Inglewood/Rose Canyon Fault in the Inner California Borderlands

    Science.gov (United States)

    Holmes, J. J.; Bormann, J. M.; Driscoll, N. W.; Kent, G.; Harding, A. J.; Wesnousky, S. G.

    2014-12-01

    The tectonic deformation and geomorphology of the Inner California Borderlands (ICB) records the transition from a convergent plate margin to a predominantly dextral strike-slip system. Geodetic measurements of plate boundary deformation onshore indicate that approximately 15%, or 6-8 mm/yr, of the total Pacific-North American relative plate motion is accommodated by faults offshore. The largest near-shore fault system, the Newport-Inglewood/Rose Canyon (NI/RC) fault complex, has a Holocene slip rate estimate of 1.5-2.0 mm/yr, according to onshore trenching, and current models suggest the potential to produce an Mw 7.0+ earthquake. The fault zone extends approximately 120 km, initiating from the south near downtown San Diego and striking northwards with a constraining bend north of Mt. Soledad in La Jolla and continuing northwestward along the continental shelf, eventually stepping onshore at Newport Beach, California. In late 2013, we completed the first high-resolution 3D seismic survey (3.125 m bins) of the NI/RC fault offshore of San Onofre as part of the Southern California Regional Fault Mapping project. We present new constraints on fault geometry and segmentation of the fault system that may play a role in limiting the extent of future earthquake ruptures. In addition, slip rate estimates using piercing points such as offset channels will be explored. These new observations will allow us to investigate recent deformation and strain transfer along the NI/RC fault system.

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    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...... 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...

  18. 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.

  19. RECALIBRATION OF H CANYON ONLINE SPECTROPHOTOMETER AT EXTENDED URANIUM CONCENTRATION

    Energy Technology Data Exchange (ETDEWEB)

    Lascola, R

    2008-10-29

    The H Canyon online spectrophotometers are calibrated for measurement of the uranium and nitric acid concentrations of several tanks in the 2nd Uranium Cycle.[1] The spectrometers, flow cells, and prediction models are currently optimized for a process in which uranium concentrations are expected to range from 0-15 g/L and nitric acid concentrations from 0.05-6 M. However, an upcoming processing campaign will involve 'Super Kukla' material, which has a lower than usual enrichment of fissionable uranium. Total uranium concentrations will be higher, spanning approximately 0-30 g/L U, with no change in the nitric acid concentrations. The new processing conditions require the installation of new flow cells with shorter path lengths. As the process solutions have a higher uranium concentration, the shorter path length is required to decrease the absorptivity to values closer to the optimal range for the instrument. Also, new uranium and nitric acid prediction models are required to span the extended uranium concentration range. The models will be developed for the 17.5 and 15.4 tanks, for which nitric acid concentrations will not exceed 1 M. The restricted acid range compared to the original models is anticipated to reduce the measurement uncertainty for both uranium and nitric acid. The online spectrophotometers in H Canyon Second Uranium Cycle were modified to allow measurement of uranium and nitric acid for the Super Kukla processing campaign. The expected uranium concentrations, which are higher than those that have been recently processed, required new flow cells with one-third the optical path length of the existing cells. Also, new uranium and nitric acid calibrations were made. The estimated reading uncertainties (2{sigma}) for Tanks 15.4 and 17.5 are {approx}5% for uranium and {approx}25% for nitric acid.

  20. 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

  1. 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.

  2. 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...

  3. Submarine canyons along the upper Sardinian slope (Central Western Mediterranean) as repositories for derelict fishing gears.

    Science.gov (United States)

    Cau, Alessandro; Alvito, Andrea; Moccia, Davide; Canese, Simonepietro; Pusceddu, Antonio; Rita, Cannas; Angiolillo, Michela; Follesa, Maria C

    2017-09-11

    By means of ROV surveys, we assessed the quantity, composition and bathymetric distribution of marine litter in 17 sites along the Sardinian continental margin (Central Western Mediterranean) at depths ranging from 100 to 480m. None of the investigated sites was litter free, but the mean density of litter (0.0175±0.0022itemsm(-2)) was lower than that reported from other Tyrrhenian regions. The difference in the total litter density among sites was negligible, but the density of derelict fishing gear (DFG) items (most of which ascribable to small scale fishery) in submarine canyons was higher in submarine canyons than in other habitats. Our result suggest that submarine canyons (known to be highly vulnerable ecosystems) act as major repositories of DFGs, and, therefore, we anticipate the need of specific measures aimed at minimizing the loss and abandonment of DFGs in submarine canyons. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. From suspended particles to strata: The fate of terrestrial substances in the Gaoping (Kaoping) submarine canyon

    Science.gov (United States)

    Liu, James T.; Hung, Jia-Jang; Lin, Hui-Ling; Huh, Chih-An; Lee, Chon-Lin; Hsu, Ray T.; Huang, Ya-Wen; Chu, Joel C.

    2009-03-01

    The river-sea system consisting of the Gaoping (new spelling according to the latest government's directive, formerly spelled Kaoping) River (KPR), shelf, and Submarine Canyon (KPRSC) located off southern Taiwan is an ideal natural laboratory to study the source, pathway, transport, and fate of terrestrial substances. In 2004 during the flood season of the KPR, a system-wide comprehensive field experiment was conducted to investigate particle dynamics from a source-to-sink perspective in the KPRSC with the emphasis on the effect of particle size on the transport, settling, and sedimentation along the pathway. This paper reports the findings from (1) two sediment trap moorings each configured with a Technicap PPS 3/3 sediment trap, and an acoustic current meter (Aquadopp); (2) concurrent hydrographic profiling and water sampling was conducted over 8 h next to the sediment trap moorings; and (3) box-coring in the head region of the submarine canyon near the mooring sites. Particle samples from sediment traps were analyzed for mass fluxes, grain-size composition, total organic carbon (TOC) and nitrogen (TN), organic matter (OM), carbonate, biogenic opal, polycyclic aromatic hydrocarbon (PAH), lithogenic silica and aluminum, and foraminiferal abundance. Samples from box cores were analyzed for grain-size distribution, TOC, particulate organic matter (POM), carbonate, biogenic opal, water content, and 210Pb ex. Water samples were filtered through 500, 250, 63, 10 µm sieves and 0.4 µm filter for the suspended sediment concentration of different size-classes. Results show that the river and shelf do not supply all the suspended particles near the canyon floor. The estimated mass flux near the canyon floor exceeds 800 g/m 2/day, whose values are 2-7 times higher than those at the upper rim of the canyon. Most of the suspended particles in the canyon are fine-grained (finer than medium silt) lithogenic sediments whose percentages are 90.2% at the upper rim and 93.6% in

  5. 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...

  6. 80 FR 9279 - Deer Flat National Wildlife Refuge, Canyon, Payette, Owyhee, and Washington Counties, ID, and...

    Science.gov (United States)

    2015-02-20

    ...-2013-N279; 1265-0000-10137-S3] Deer Flat National Wildlife Refuge, Canyon, Payette, Owyhee, and..., 1010 Dearborn St, Caldwell, ID 83605. [ssquf] Homedale Public Library, 125 W Owyhee Ave, Homedale,...

  7. 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...

  8. 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...

  9. 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...

  10. Lightning protection for the process canyons at the Savannah River site

    Energy Technology Data Exchange (ETDEWEB)

    McAfee, D.E.

    1995-12-31

    Westinghouse Savannah River Company (WSRC) has performed Lightning Studies for the existing Process Canyons at the Savannah River Site (SRS). These studies were initiated to verify the lightning protection systems for the facilities and to compare the installations to the National Fire Protection (NFPA) Standard 780, Lighting Protection Code, 1992. The original study of the F-Canyon was initiated to develop answers to concerns raised by the Defense Nuclear Facility Safety Board (DNFSB). Once this study was completed it was determined that a similar study for H-Canyon would be prudent; followed by an evaluation of the Defense Waste Processing Facility (DWPF) Vitrification Building (S-Canyon). This paper will provide an overview of the nature of lightning and the principals of lightning protection. This will provide the reader with a basic understanding of the phenomena of lighting and its potential for damaging structures, components, and injuring personnel in or near the structure.

  11. On Line Spectrophotometric Measurement of Uranium and Nitrate in H Canyon

    Energy Technology Data Exchange (ETDEWEB)

    Lascola, R.J.

    2002-10-15

    This report describes the on-line instrumentation developed by the Analytical Development Section of Savannah River Technology Center in support of Highly Enriched Uranium Blend Down processing in H Canyon.

  12. 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.

  13. 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 of...

  14. Angel Lichen Moth Abundance and Morphology Data, Grand Canyon, AZ, 2012

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Two unique datasets on the abundance and morphology of the angel lichen moth (Cisthene angelus) in Grand Canyon, Arizona, USA were compiled to describe the phenology...

  15. 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...

  16. 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)...

  17. Boundary for Black Canyon of the Gunnison National Park (BLCA), Colorado (2002)

    Data.gov (United States)

    National Park Service, Department of the Interior — This administrative boundary for Black Canyon of the Gunnison National Park (BLCA), Colorado contains 6 polygons showing National Park Service (NPS) lands, and...

  18. Origin of Theater-headed Tributaries to Escalante and Glen Canyons, Utah

    Science.gov (United States)

    Irwin, R. P.; Fortezzo, C. M.; Tooth, S. E.; Howard, A. D.; Zimbelman, J. R.; Barnhart, C. J.; Benthem, A. J.; Brown, C. C.; Parsons, R. A.

    2009-03-01

    Theater-headed tributaries to Glen Canyon, Utah, are important analogs to martian valley networks. Our field study suggests a hybrid model involving seepage weathering of Navajo sandstone, sheet fracturing, and transport of debris by flash floods.

  19. 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...

  20. 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 performance...... of low-energy buildings in a north-European setting is affected by their context.This study uses a comprehensive suite of climate-based dynamic thermal and daylight simulations to describe how these primary factors in the passive energy properties of buildings are affected by increases in urban density.......It was found that the geometry of urban canyons has an impact on total energy consumption in the range of up to +30% for offices and +19% for housing, which shows that the geometry of urban canyons is a key factor in energy use in buildings. It was demonstrated how the reflectivity of urban canyons plays...

  1. Fire modeling for Building 221-T - T Plant Canyon Deck and Railroad Tunnel

    Energy Technology Data Exchange (ETDEWEB)

    Oar, D.L.

    1994-09-29

    This report was prepared by Hughes Associates, Inc. to document the results of fire models for building 221-T Canyon Deck and Railroad Tunnel. Backup data is contained in document No. WHC-SD-CP-ANAL-010, Rev. 0.

  2. 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...

  3. 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.

  4. Seismic evidence of conjugate normal faulting: The 1994 Devil Canyon earthquake sequence near Challis, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, Suzette M. [Boise State Univ., ID (United States)

    1994-08-01

    Aftershock hypocenters of the 1984 Devil Canyon, Idaho earthquake indicate the sequence was associated with conjugate normal faulting on two northwest-striking normal faults that bound the Warm Spring Creek graben.

  5. 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...

  6. Status and Trends of the Grand Canyon Population of Humpback Chub

    Science.gov (United States)

    Andersen, Matthew E.

    2009-01-01

    The Colorado River Basin supports one of the most distinctive fish communities in North America, including the federally endangered humpback chub (Gila cypha). One of only six remaining populations of this fish is found in Grand Canyon, Arizona. U.S. Geological Survey scientists and their cooperators are responsible for monitoring the Grand Canyon population. Analysis of recently collected data indicates that the number of Grand Canyon adult humpback chub - fish 4 years old and older and capable of reproduction - increased approximately 50 percent between 2001 and 2008. When possible model error is considered, the estimated number of adult chub in the Grand Canyon population is between 6,000 and 10,000. The most likely number is estimated at 7,650 individuals.

  7. Southwestern Riparian Plant Trait Matrix, Colorado River, Grand Canyon, Arizona, 2014 - 2016—Data

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset contains information on the physical traits and environmental tolerances of plant species occurring along the lower Colorado River through Grand Canyon....

  8. 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...

  9. Temperature decreases in an urban canyon due to green walls and green roofs in diverse climates

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Phil [Cardiff University (United Kingdom). Welsh School of Architecture; Alexandri, Eleftheria

    2008-04-15

    This paper discusses the thermal effect of covering the building envelope with vegetation on the microclimate in the built environment, for various climates and urban canyon geometries. A two-dimensional, prognostic, micro scale model has been used, developed for the purposes of this study. The climatic characteristics of nine cities, three urban canyon geometries, two canyon orientations and two wind directions are examined. The thermal effect of green roofs and green walls on the built environment is examined in both inside the canyon and at roof level. The effects of this temperature decrease on outdoors thermal comfort and energy savings are examined. Conclusions are drawn on whether plants on the building envelope can be used to tackle the heat island effect, depending on all these parameters taken into consideration. (author)

  10. 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...

  11. 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...

  12. Giant landslides and turbidity currents in the Agadir Canyon Region, NW-Africa

    Science.gov (United States)

    Krastel, Sebastian; Wynn, Russell B.; Stevenson, Christopher; Feldens, Peter; Mehringer, Lisa; Schürer, Anke

    2017-04-01

    Coring and drilling of the Moroccan Turbidite System off NW-Africa revealed a long sequence of turbidites, mostly sourced from the Moroccan continental margin and the volcanic Canary Islands. The largest individual flow deposits in the Moroccan Turbidite System contain sediment volumes >100 km3, although these large-scale events are relatively infrequent with a recurrence interval of 10,000 years (over the last 200,000 years). The largest siliciclastic flow in the last 200,000 years was the 'Bed 5 event', which transported 160 km3 of sediment up to 2000 km from the Agadir Canyon region to the southwest Madeira Abyssal Plain. While the Moroccan Turbidite System is extremely well investigated, almost no data from the source region, i.e. the Agadir Canyon, are available. Understanding why some submarine landslides remain as coherent blocks of sediment throughout their passage downslope, while others mix and disintegrate almost immediately after initial failure, is a major scientific challenge, which was addressed in the Agadir Canyon source region during RV Maria S. Merian Cruise MSM32 in late 2013. A major landslide area was identified 200 km south of the Agadir Canyon. A landslide was traced from this failure area to the Agadir Canyon. This landslide entered the canyon in about 2500 m water depth. Despite a significant increase in slope angle, the landslide did not disintegrate into a turbidity current when entering the canyon but moved on as landslide for at least another 200 km down the canyon. The age of the landslide ( 145 ka) does not correspond to any major turbidte deposit in the Moroccan Turbidite System, further supporting the fact that the landslide did not disintegrate into a major turbidity current. A core taken about 350 m above the thalweg in the head region of Agadir Canyon shows a single coarse-grained turbidite, which resembles the composition of the Bed 5 event in the Madeira Abyssal Plain. Hence, the Bed 5 turbidite originated as a failure in the

  13. Internal tides affect benthic community structure in an energetic submarine canyon off SW Taiwan

    Science.gov (United States)

    Liao, Jian-Xiang; Chen, Guan-Ming; Chiou, Ming-Da; Jan, Sen; Wei, Chih-Lin

    2017-07-01

    Submarine canyons are major conduits of terrestrial and shelf organic matter, potentially benefiting the seafloor communities in the food-deprived deep sea; however, strong bottom currents driven by internal tides and the potentially frequent turbidity currents triggered by storm surges, river flooding, and earthquakes may negatively impact the benthos. In this study, we investigated the upper Gaoping Submarine Canyon (GPSC), a high-sediment-yield canyon connected to a small mountain river (SMR) off southwest (SW) Taiwan. By contrasting the benthic meiofaunal and macrofaunal communities within and outside the GPSC, we examined how food supplies and disturbance influenced the benthic community assemblages. The benthic communities in the upper GPSC were mainly a nested subset of the adjacent slope assemblages. Several meiofaunal (e.g. ostracods) and macrofaunal taxa (e.g. peracarid crustaceans and mollusks) that typically occurred on the slope were lost from the canyon. The polychaete families switched from diverse feeding guilds on the slope to motile subsurface deposit feeders dominant in the canyon. The diminishing of epibenthic peracarids and proliferation of deep burrowing polychaetes in the GPSC resulted in macrofauna occurring largely within deeper sediment horizons in the canyon than on the slope. The densities and numbers of taxa were depressed with distinct and more variable composition in the canyon than on the adjacent slope. Both the densities and numbers of taxa were negatively influenced by internal tide flushing and positively influenced by food availability; however, the internal tides also negatively influenced the food supplies. While the meiofauna and macrofauna densities were both depressed by the extreme physical conditions in the GPSC, only the macrofaunal densities increased with depth in the canyon, presumably related to increased frequency and intensity of disturbance toward the canyon head. The population densities of meiofauna, on the

  14. Amphibian acoustic data from the Arizona 1, Pinenut, and Canyon breccia pipe uranium mines in Arizona

    Science.gov (United States)

    Hinck, Jo E.; Hossack, Blake R.; Honeycutt, Richard

    2017-01-01

    The data consists of a summary of amphibian acoustic recordings at Canyon, Arizona 1, and Pinenut mines near the Grand Canyon. USGS is currently conducting biological surveys associated with uranium mines on federal lands in Arizona. These surveys include determining the composition of the local amphibian community. Original raw acoustic recordings used to create this summary data table are archived at Columbia Environmental Research Center.

  15. Canyon and channel networks of Peru-Chile fore arc at Arica Bight

    Energy Technology Data Exchange (ETDEWEB)

    Coulbourn, W.T. (Hawaii Institute of Geophysics, Honolulu (USA))

    1990-05-01

    Canyons and channels of the Peru-Chile fore arc between 17{degree}30'S to 19{degree}30'S form a complex, integrated network revealed in SeaMARC II side-scan mosaics. The largest canyon, incised 200-600 m, is bordered by a series of sidewall slumps, producing a sinuosity that mimics subaerial meanders. The canyon courses across the Arequipa fore-arc basin floor, across a structural high and onto the middle trench slope to about 4,000 m where it disappears into a background of complex small-scale structures, From 500-2,500 m depth the canyon strikes north-south oblique to the regional slope. At 2,500 m, it abruptly turns to the southwest toward the trench axis. At this elbow, a second canyon heads on the midslope and also trends north-south until 3,500 m, where it too abruptly changes to a southwest course. A history of stream piracy analogous to subaerial systems is implied in this geometry. Tributaries join this main canyon from the landward side, forming a dendritic pattern. These channels have levees which are linked by submarine crevasse splays to sediment waves on the Arequipa basin floor. The orientation of the waves is reminiscent of bow waves from a passing ship, oblique to channel and pointing downslope, and may provide an indication of the vertical extent of passing turbidity currents. Sediments are dominantly olive gray, hemipelagic silts with sands present only immediately adjacent to the canyons. Boulders of mudstone line portions of the canyon floor. Sands are absent from the lowermost slope and trench axis, as are any indications of submarine fans. Sands may be rare in this system, with those that are present kneaded into the active margin system along the lower trench slope.

  16. Cold-Water Coral Habitats in Submarine Canyons of the Bay of Biscay

    Directory of Open Access Journals (Sweden)

    Inge M. J. van den Beld

    2017-05-01

    Full Text Available The topographical and hydrological complexity of submarine canyons, coupled with high substratum heterogeneity, make them ideal environments for cold-water coral (CWC habitats. These habitats, including reefs, are thought to provide important functions for many organisms. The canyons incising the continental slope of the Bay of Biscay have distinct morphological differences from the north to the south. CWCs have been reported from this basin in the late nineteenth century; however, little is known about their present-day distribution, diversity and environmental drivers in the canyons. In this study, the characteristics and distribution of CWC habitats in the submarine canyons of the Bay of Biscay are investigated. Twenty-four canyons and three locations between adjacent canyons were sampled using a Remotely Operated Vehicle (ROV or a towed camera system. Acquired images were annotated for habitat type (using the CoralFISH classification system, substrate cover and coral identification. Furthermore, the influence of hydrological factors and geomorphology on the CWC distribution was investigated. Eleven coral habitats, formed by 62 morphotypes of scleractinians, gorgonians, antipatharians and seapens, inhabiting hard and/or soft substrate, were observed. The distribution patterns were heterogenous at regional and local scales; the south Bay of Biscay and the southeastern flank favored soft substrate habitats. Biogenic and hard substrate habitats supported higher coral diversities than soft substrate habitats and had similar species compositions. A higher coral species turnover characterized soft substrate habitats. Substrate type was the most important driver of the patterns in both distribution and composition. Observations of coral reefs on steeper areas in the canyons and coral rubble on flatter areas on the interfluve/upper slope support the hypothesis that canyons serve as refuges, being less accessible to trawling, although natural causes

  17. 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.

  18. Outburst fan deposit from pyroclastic flows, Williamson River canyon, south-central Oregon

    Science.gov (United States)

    Cummings, M. L.; Eibert, D.

    2016-12-01

    Pyroclastic flows from the Holocene eruption of Mount Mazama in the Cascade volcanic arc of Oregon, blocked the narrow (210 to 225 m wide, 35 to 40 m deep), bedrock-lined canyon of the Williamson River. The estimated volume of the long, narrow blockage was 4.4 x 10^7 cubic meters. The blockage eventually failed releasing an impounded lake and depositing a debris fan at the mouth of the canyon. Remnants of the debris fan underlie a gently sloping surface dissected by various abandoned channels of the river. The modern Williamson River cut its channel across the upper part of the fan. Three bedrock units are present as boulders: hydrovolcanic tuff (Di = 2.75 m) derived from tuff cones in the lower reaches of the canyon, distinctly layered geochemically primitive olivine basalt (Di = 3.4 m) that crops out approximately 6 km upstream, and massive basaltic andesite that underlies the channel in the upper canyon and cliffs that define the right bank of the canyon near the mouth. Matrix between boulders and deposits that flank and overlie the boulder deposit are dominated by medium- to fine-grained sand (ASTM; 61-70 wt. % in matrix; 76-100 wt. % elsewhere). Sand grains are predominantly well-rounded phenocryst-bearing glass that vary from massive to moderately vesiculated and crystals of plagioclase and hornblende commonly with attached remnants of groundmass. Crystals are most abundant in the medium- and fine-grained size range (>20 and fragments (twigs and molds) are common in medium-sand and larger. Elongate bars of rounded pumice gravel provide local current directions during the waning stage of the outburst flood. The thickness of the boulder deposit near the mouth of the canyon is not known. Sand deposits are 1 to 1.5 m thick near the mouth of the canyon and thin to 70 cm at about 3.4 km from the mouth of the canyon.

  19. Yuntaishan Global Geopark VS Grand Canyon World Heritage Site A Contrast of Yuntai/Grand Canyon Physiognomy

    Science.gov (United States)

    Ting, Zhao; Xun, Zhao

    2017-04-01

    Yuntai/Grand Canyon is a result of long-term historical evolution and a rare natural heritage of the world. With its rich heritages of geological physiognomy, systematic geological record, abundant biological fossil combination, long history of structural evolution, they are of contrastive research values worldwide. The Grand Canyon was declared national natural heritage on eleventh January, and in 1979 it was entitled World Natural Heritage Site. Though the two major sites are separated by tremendous seas, they reached agreements in the protection of natural heritages worldwide on account of the shared ideas of society, demonstrating to our children how can we protect the two scenery sites. Keyword:Geopark, Geoheritage, Yuntai Landform, GrandCanyon Mt. Taihang rises from the central part of north China and extends to the west edge of North China Plain. Towering, and with ragged peaks, precarious cliffs, long strips of walls, deep valleys and shaded streams, Mt. Taihang poses impressive sights with its clear water, dense forest and wonderful sceneries. It is indeed the east slope of Qin-Jin Plateau. Indeed things tend to coincide. On the other side of the Pacific Ocean, along the west edge of north America and on the wide and spacious Colorado Plateau, there is a winding and deep valley where there are layers of rocks, extensive sharp cliffs, intercrossing ravines and forests of peaks; it is totally impressive. Both sceneries are known to the world for their beauty. Identical geological conditions and similar history of evolution left two natural sights that resemble each other so much. Geological changes are infinite, and sedimentation works in similar ways on both sights; and the changing ecological environment gives the world two colorful and comparable geological records. Both sights are merely brief periods in the long history of earth development, but they show us how cradles of human proliferation and social civilization had looked. 1,Comparison of two parks

  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. San Pascual (1991) Año XXVIII, n. 284

    OpenAIRE

    Pérez, María Dolores, O.S.C. (Directora)

    1991-01-01

    Editorial. Documento de la Santa sede. San Pascual y la Virgen de Gracia. Nueva revista dedicada a San Pascual. Adoración nocturna. Desde la clausura. Vida en el santuario de San Pascual. Orden Franciscana. Coplas a San Pascual Baylón. San Pascual en el arte. Rutas pascualinas. A l'ombra del claustre.

  2. San Pascual (1991) Año XXVIII, n. 284

    OpenAIRE

    Pérez, María Dolores, O.S.C. (Directora)

    1991-01-01

    Editorial. Documento de la Santa sede. San Pascual y la Virgen de Gracia. Nueva revista dedicada a San Pascual. Adoración nocturna. Desde la clausura. Vida en el santuario de San Pascual. Orden Franciscana. Coplas a San Pascual Baylón. San Pascual en el arte. Rutas pascualinas. A l'ombra del claustre.

  3. Mixing and phytoplankton dynamics in a submarine canyon in the West Antarctic Peninsula

    Science.gov (United States)

    Carvalho, Filipa; Kohut, Josh; Oliver, Matthew J.; Sherrell, Robert M.; Schofield, Oscar

    2016-07-01

    Bathymetric depressions (canyons) exist along the West Antarctic Peninsula shelf and have been linked with increased phytoplankton biomass and sustained penguin colonies. However, the physical mechanisms driving this enhanced biomass are not well understood. Using a Slocum glider data set with over 25,000 water column profiles, we evaluate the relationship between mixed layer depth (MLD, estimated using the depth of maximum buoyancy frequency) and phytoplankton vertical distribution. We use the glider deployments in the Palmer Deep region to examine seasonal and across canyon variability. Throughout the season, the ML becomes warmer and saltier, as a result of vertical mixing and advection. Shallow ML and increased stratification due to sea ice melt are linked to higher chlorophyll concentrations. Deeper mixed layers, resulting from increased wind forcing, show decreased chlorophyll, suggesting the importance of light in regulating phytoplankton productivity. Spatial variations were found in the canyon head region where local physical water column properties were associated with different biological responses, reinforcing the importance of local canyon circulation in regulating phytoplankton distribution in the region. While the mechanism initially hypothesized to produce the observed increases in phytoplankton over the canyons was the intrusion of warm, nutrient enriched modified Upper Circumpolar Deep Water (mUCDW), our analysis suggests that ML dynamics are key to increased primary production over submarine canyons in the WAP.

  4. 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.

  5. Effect of stable stratification on dispersion within urban street canyons: A large-eddy simulation

    Science.gov (United States)

    Li, Xian-Xiang; Britter, Rex; Norford, Leslie K.

    2016-11-01

    This study employs a validated large-eddy simulation (LES) code with high tempo-spatial resolution to investigate the effect of a stably stratified roughness sublayer (RSL) on scalar transport within an urban street canyon. The major effect of stable stratification on the flow and turbulence inside the street canyon is that the flow slows down in both streamwise and vertical directions, a stagnant area near the street level emerges, and the vertical transport of momentum is weakened. Consequently, the transfer of heat between the street canyon and overlying atmosphere also gets weaker. The pollutant emitted from the street level 'pools' within the lower street canyon, and more pollutant accumulates within the street canyon with increasing stability. Under stable stratification, the dominant mechanism for pollutant transport within the street canyon has changed from ejections (flow carries high-concentration pollutant upward) to unorganized motions (flow carries high-concentration pollutant downward), which is responsible for the much lower dispersion efficiency under stable stratifications.

  6. Geologic map and upper Paleozoic stratigraphy of the Marble Canyon area, Cottonwood Canyon quadrangle, Death Valley National Park, Inyo County, California

    Science.gov (United States)

    Stone, Paul; Stevens, Calvin H.; Belasky, Paul; Montañez, Isabel P.; Martin, Lauren G.; Wardlaw, Bruce R.; Sandberg, Charles A.; Wan, Elmira; Olson, Holly A.; Priest, Susan S.

    2014-01-01

    This geologic map and pamphlet focus on the stratigraphy, depositional history, and paleogeographic significance of upper Paleozoic rocks exposed in the Marble Canyon area in Death Valley National Park, California. Bedrock exposed in this area is composed of Mississippian to lower Permian (Cisuralian) marine sedimentary rocks and the Jurassic Hunter Mountain Quartz Monzonite. These units are overlain by Tertiary and Quaternary nonmarine sedimentary deposits that include a previously unrecognized tuff to which we tentatively assign an age of late middle Miocene (~12 Ma) based on tephrochronologic analysis, in addition to the previously recognized Pliocene tuff of Mesquite Spring. Mississippian and Pennsylvanian rocks in the Marble Canyon area represent deposition on the western continental shelf of North America. Mississippian limestone units in the area (Tin Mountain, Stone Canyon, and Santa Rosa Hills Limestones) accumulated on the outer part of a broad carbonate platform that extended southwest across Nevada into east-central California. Carbonate sedimentation was interrupted by a major eustatic sea-level fall that has been interpreted to record the onset of late Paleozoic glaciation in southern Gondwana. Following a brief period of Late Mississippian clastic sedimentation (Indian Springs Formation), a rise in eustatic sea level led to establishment of a new carbonate platform that covered most of the area previously occupied by the Mississippian platform. The Pennsylvanian Bird Spring Formation at Marble Canyon makes up the outer platform component of ten third-order (1 to 5 m.y. duration) stratigraphic sequences recently defined for the regional platform succession. The regional paleogeography was fundamentally changed by major tectonic activity along the continental margin beginning in middle early Permian time. As a result, the Pennsylvanian carbonate shelf at Marble Canyon subsided and was disconformably overlain by lower Permian units (Osborne Canyon and

  7. Species - San Diego Co. [ds121

    Data.gov (United States)

    California Department of Resources — This is the Biological Observation Database point layer representing baseline observations of sensitive species (as defined by the MSCP) throughout San Diego County....

  8. 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

  9. 33 CFR 165.1102 - Security Zone; Naval Base Point Loma; San Diego Bay, San Diego, CA.

    Science.gov (United States)

    2010-07-01

    ... Loma; San Diego Bay, San Diego, CA. 165.1102 Section 165.1102 Navigation and Navigable Waters COAST... Guard District § 165.1102 Security Zone; Naval Base Point Loma; San Diego Bay, San Diego, CA. (a) Location. The following area is a security zone: The water adjacent to the Naval Base Point Loma, San Diego...

  10. 77 FR 57494 - Safety Zone; Fleet Week Fireworks, San Francisco Bay, San Francisco, CA

    Science.gov (United States)

    2012-09-18

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zone; Fleet Week Fireworks, San Francisco Bay, San Francisco... will enforce the safety zone for the Fleet Week Fireworks in the Captain of the Port, San Francisco...'' W (NAD83) for the Fleet Week Fireworks in 33 CFR 165.1191, Table 1, item number 25. This safety...

  11. 78 FR 10062 - Safety Zone; Sea World San Diego Fireworks, Mission Bay; San Diego, CA

    Science.gov (United States)

    2013-02-13

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Sea World San Diego Fireworks, Mission Bay; San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a safety zone on the navigable waters of Mission Bay in support of the Sea World San Diego...

  12. 77 FR 42649 - Safety Zone: Sea World San Diego Fireworks, Mission Bay; San Diego, CA

    Science.gov (United States)

    2012-07-20

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone: Sea World San Diego Fireworks, Mission Bay; San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is... rule, call or email Petty Officer David Varela, Waterways Management, U.S. Coast Guard Sector San Diego...

  13. 77 FR 60899 - Safety Zone; Sea World San Diego Fireworks, Mission Bay; San Diego, CA

    Science.gov (United States)

    2012-10-05

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Sea World San Diego Fireworks, Mission Bay; San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a safety zone on the navigable waters of Mission Bay in support of the Sea World San Diego...

  14. 77 FR 42638 - Safety Zone: Sea World San Diego Fireworks, Mission Bay; San Diego, CA

    Science.gov (United States)

    2012-07-20

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone: Sea World San Diego Fireworks, Mission Bay; San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a safety zone on the navigable waters of Mission Bay in support of the Sea World San Diego...

  15. 78 FR 29025 - Sea World San Diego Fireworks 2013 Season; Mission Bay, San Diego, CA

    Science.gov (United States)

    2013-05-17

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Sea World San Diego Fireworks 2013 Season; Mission Bay, San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a safety zone on the navigable waters of Mission Bay in support of the Sea World San Diego...

  16. 76 FR 46352 - Approval of Noise Compatibility Program for San Diego International, San Diego, CA

    Science.gov (United States)

    2011-08-02

    ... Federal Aviation Administration Approval of Noise Compatibility Program for San Diego International, San Diego, CA AGENCY: Federal Aviation Administration, DOT. ACTION: Notice . SUMMARY: The Federal Aviation Administration (FAA) announces its findings on the noise compatibility program submitted by San Diego Regional...

  17. 78 FR 77597 - Safety Zone; Allied PRA-Solid Works, San Diego Bay; San Diego, CA

    Science.gov (United States)

    2013-12-24

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Allied PRA-Solid Works, San Diego Bay; San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone on the navigable waters of the San Diego Bay in support of a fireworks...

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

    Directory of Open Access Journals (Sweden)

    S. Pando

    2013-01-01

    Full Text Available 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. After validation, a Lagrangian transport model was coupled to the hydrodynamic model to study the transport patterns of the organo-mineral aggregates along the Nazaré canyon comparing three different classes of organo-mineral aggregates. The results showed that the transport in the canyon is neither constant, nor unidirectional and that there are preferential areas where suspended matter is resuspended, transported and deposited. The results showed that the transport of the larger size classes of organo-mineral aggregates is less pronounced, and that there is a decrease in the phytodetrital carbon flux along the canyon. The Nazaré canyon acts as depocenter of sedimentary organic matter and the canyon is not a conduit of organo-mineral aggregates to the deep sea.

  19. Central San Juan caldera cluster: regional volcanic framework

    Science.gov (United States)

    Lipman, Peter W.

    2000-01-01

    Eruption of at least 8800 km3 of dacitic-rhyolitic magma as 9 major ash-slow sheets (individually 150-5000 km3) was accompanied by recurrent caldera subsidence between 28.3 and about 26.5 Ma in the central San Juan Mountains, Colorado. Voluminous andesitic-decitic lavas and breccias were erupted from central volcanoes prior to the ash-flow eruptions, and similar lava eruptions continued within and adjacent to the calderas during the period of explosive volcanism, making the central San Juan caldera cluster an exceptional site for study of caldera-related volcanic processes. Exposed calderas vary in size from 10 to 75 km in maximum diameter, the largest calderas being associated with the most voluminous eruptions. After collapse of the giant La Garita caldera during eruption if the Fish Canyon Tuff at 17.6 Ma, seven additional explosive eruptions and calderas formed inside the La Garita depression within about 1 m.y. Because of the nested geometry, maximum loci of recurrently overlapping collapse events are inferred to have subsided as much as 10-17 km, far deeper than the roof of the composite subvolcanic batholith defined by gravity data, which represents solidified caldera-related magma bodies. Erosional dissection to depths of as much as 1.5 km, although insufficient to reach the subvolcanic batholith, has exposed diverse features of intracaldera ash-flow tuff and interleaved caldera-collapse landslide deposits that accumulated to multikilometer thickness within concurrently subsiding caldera structures. The calderas display a variety of postcollapse resurgent uplift structures, and caldera-forming events produced complex fault geometries that localized late mineralization, including the epithermal base- and precious-metal veins of the well-known Creede mining district. Most of the central San Juan calderas have been deeply eroded, and their identification is dependent on detailed geologic mapping. In contrast, the primary volcanic morphology of the

  20. 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

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

    OpenAIRE

    S. Pando; Juliano, M.; Garcia, 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. After validation, a Lagrangian transport model was coupled to the hydrodynamic model to study the transport patterns of the organo-mineral aggregates along the Nazaré canyon comparing three different classes of organo-mineral aggregates. The results showed that the transport in the canyon is neither constant, nor unid...

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

    OpenAIRE

    Pando, S.; Juliano, M.; Garcia, 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. After validation, a Lagrangian transport model was coupled to the hydrodynamic model to study the transport patterns of the organo-mineral aggregates along the Nazaré canyon comparing three different classes of organo-mineral aggregates. The results showed that the transport in the canyon is neither constant, nor unid...

  3. Zooplankton and Micronekton Distribution and Interaction with Predators at the Northwest Atlantic Shelf Break and its Canyons

    Science.gov (United States)

    2014-09-30

    with Predators at the Northwest Atlantic Shelf Break and its Canyons Gareth L. Lawson, Andone C. Lavery, & Peter H. Wiebe Woods Hole...mammals, seabirds, and fish) at the northwest Atlantic continental shelf break and its canyons , inclusive of the role of inter-annual variability and...collected at the New England shelf break and its canyons in 2005 and 2009-2013. These existing data were all collected under small awards internal

  4. Cuartel San Carlos. Yacimiento veterano

    Directory of Open Access Journals (Sweden)

    Mariana Flores

    2007-01-01

    Full Text Available El Cuartel San Carlos es un monumento histórico nacional (1986 de finales del siglo XVIII (1785-1790, caracterizado por sufrir diversas adversidades en su construcción y soportar los terremotos de 1812 y 1900. En el año 2006, el organismo encargado de su custodia, el Instituto de Patrimonio Cultural del Ministerio de Cultura, ejecutó tres etapas de exploración arqueológica, que abarcaron las áreas Traspatio, Patio Central y las Naves Este y Oeste de la edificación. Este trabajo reseña el análisis de la documentación arqueológica obtenida en el sitio, a partir de la realización de dicho proyecto, denominado EACUSAC (Estudio Arqueológico del Cuartel San Carlos, que representa además, la tercera campaña realizada en el sitio. La importancia de este yacimiento histórico, radica en su participación en los acontecimientos que propiciaron conflictos de poder durante el surgimiento de la República y en los sucesos políticos del siglo XX. De igual manera, se encontró en el sitio una amplia muestra de materiales arqueológicos que reseñan un estilo de vida cotidiana militar, así como las dinámicas sociales internas ocurridas en el San Carlos, como lugar estratégico para la defensa de los diferentes regímenes que atravesó el país, desde la época del imperialismo español hasta nuestros días.

  5. 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

  6. 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

  7. 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

  8. Downtown revitalization in San Salvador

    OpenAIRE

    Ejeborn, Elisabet; Nedersjö, Julia

    2012-01-01

    The aim of this master’s thesis in spatial planning is to research the conditions in the historic city centre of San Salvador and make a strategy and urban design proposal for the area, but also to investigate the relationship between economic development, public institutions and the public space in this area. The research has been done through literature studies on El Salvador and formal/informal economy, onsite inventory, studies of good examples and interviews with people in the area. In t...

  9. Downtown revitalization in San Salvador

    OpenAIRE

    Ejeborn, Elisabet; Nedersjö, Julia

    2012-01-01

    The aim of this master’s thesis in spatial planning is to research the conditions in the historic city centre of San Salvador and make a strategy and urban design proposal for the area, but also to investigate the relationship between economic development, public institutions and the public space in this area. The research has been done through literature studies on El Salvador and formal/informal economy, onsite inventory, studies of good examples and interviews with people in the area. In t...

  10. 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.

  11. Submarine canyon morphologies and evolution on a modern carbonate system: the Northern Slope of Little Bahama Bank (Bahamas).

    Science.gov (United States)

    Tournadour, Elsa; Mulder, Thierry; Borgomano, Jean; Hanquiez, Vincent; Ducassou, Emmanuelle; Gillet, Hervé; Sorriaux, Patrick

    2013-04-01

    The recent CARAMBAR cruise (Nov. 2010) on the northern slope of Little Bahama Bank (LBB, Bahamas) provided new seafloor and subsurface data, that improve our knowledge on carbonate slope systems. The new high-resolution multibeam bathymetry data (Kongsberg EM302 echosounder) and very high resolution (3.5 kHz/Chirp subbotom profiler) seismic data show that the upper LBB slope is dissected by 18 canyons. These canyons evolve sharply into short channels opening to depositional fan-shaped lobes. These architectural elements form a narrow carbonate gravity system extending over 40 km along the LBB slope. The features previously described as small linear canyons have a more complex morphology than originally supposed. The several architectural elements that can be distinguished share similar characteristics with siliciclastic canyons. The average morphological features of the canyons are: minimum and maximum water depths of 460 and 970 m resp., mean length = 16.3 km and sinuosity = 1.14. Canyons are floored with flat elongated morphologies interpreted as terraces. Some of these terraces are located at the toe of slide scars on canyon heads and canyon sides which suggest that they result from sediment failures. On the Chirp seismic data, wedge-shape aggrading terraces interpreted as "internal levees" can be observed. These terraces would then be formed by overbanking of the upper part of turbidity currents. Between 530 and 630 m water depth, some canyons exhibit an amphitheater-shaped head with a head wall height ranging from 80 to 100 m. The wall edges of these canyon heads consist of coalescing arcuate slump scars, which suggests that the canyons formed by retrogressive erosion. Other canyons show an amphitheater-shaped head that evolves upslope into linear valleys incising the upper slope between 460 m and 530 m water depth. The onset and the spatial distribution of these linear valleys seem to be influenced by sediments transported from oolitic shoals of Walker Cay

  12. Combined Mobile In Situ and Remote Sensing Investigation of the Aliso Canyon Natural Gas Leak in the Los Angeles Basin, California

    Science.gov (United States)

    Hall, J. L.; Leifer, I.; Tratt, D. M.; Melton, C.; Frash, J.

    2016-12-01

    The Aliso Canyon natural gas leak in the San Fernando Valley in Los Angeles, California was a major disruptive event whose societal impacts have continued well after the event itself ended, yet fortunately did not involve highly toxic gases. Chemical releases can have serious consequences for ecosystems, societies, and human health. Mitigating their destructive impacts relies on identification and mapping, monitoring, and trajectory forecasting. Improvements in the accuracy of such transport modeling capabilities can significantly improve the effectiveness of disaster response activities. Simultaneous plume characterization data were collected by the Mobile Infrared Sensor for Tactical Incident Response (MISTIR) and AutoMObile trace Gas (AMOG) Surveyor, two instrumented vehicles traveling in convoy. Surface vehicles have advantages over airplanes in terms of simpler logistics, such as not being limited by controlled airspace which is a major issue in Los Angeles, and ability to deploy rapidly. Moreover, it is the surface concentration that impacts human health and determines ecological damage. Fusion of the resulting correlative surface in situ observations and thermal-infrared spectroscopic column observations allowed both lateral and temporal plume characterization to derive emissions and to characterize the confining effect of topography on plume dispersion. Although a straightforward Gaussian plume inversion approach based on surface data yields an emission estimate with reasonable fidelity, it required assumptions of vertical profile and topographic influence that were validated by the column spectroscopic observations. Topographic factors within the Los Angeles Basin, including the Aliso Canyon locale, strongly influence transport processes. This situation challenges the predictive skill of numerical transport models that are used to assist the evacuation of at-risk communities, for example in the case of a refinery fire. This study demonstrated the utility

  13. 3-d Circulation In The PalamÓs Canyon: Observations and Modeling

    Science.gov (United States)

    Pascual, A.; Jordi, A.; Marcos, M.; Ruiz, S.; Basterretxea, G.; Gomis, D.; Emelianov, M.; Martín, J.; Font, J.; Tintoré, J.; Palanques, A.

    Along the northeast Spanish coast the Northern current interacts with abrupt canyon topography. Previous studies in the region have shown some evidences of flow modi- fications (in terms of meanders, eddies, shelf-slope exchanges) that are likely related to the presence of the canyons. Moreover, these canyons are known to be areas of en- hanced biological production compared to the surrounding shelf. However, the physi- cal mechanisms governing this increased activity are poorly understood since most of the existing samplings are too coarse for an accurate inference of dynamical variables. In this work we present results from an intensive field study (CAÑONES II) in the Palamós Canyon, which took place between 24 and 31 May 2001. An area of 80x70 km2 was covered by CTD stations separated 4 km just over the canyon (a subdomain of 25x40 km2) and 8 km elsewhere. The data were interpolated onto a regular grid and the quasi-geostrophic 3D circulation was computed. The horizontal geostrophic velocity is in good agreement with ADCP and current-meter observations. Down- welling occurs in the upstream wall of the canyon whereas vertical upward velocities of up to 50 m/day are obtained in the canyon axis. The relative importance of strati- fication and relative vorticity in the Rossby-Ertel potential vorticity is also examined along selected isopycnals, in order to understand the physical mechanisms governing the observed circulation. Particle trajectories were also computed from the 3D velocity field (assumed to be stationary) with the aim to understand the possible implications of these physical features on the marine ecosystem. All the inferred circulation features have been compared with numerical simulations obtained from a primitive equation coastal ocean model initialized with the in situ observed data.

  14. 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.

  15. H-CANYON AIR EXHAUST TUNNEL INSPECTION VEHICLE DEVELOPMENT

    Energy Technology Data Exchange (ETDEWEB)

    Minichan, R.; Fogle, R.; Marzolf, A.

    2011-05-24

    The H-Canyon at Savannah River Site is a large concrete structure designed for chemical separation processes of radioactive material. The facility requires a large ventilation system to maintain negative pressure in process areas for radioactive contamination control and personnel protection. The ventilation exhaust is directed through a concrete tunnel under the facility which is approximately five feet wide and 8 feet tall that leads to a sand filter and stack. Acidic vapors in the exhaust have had a degrading effect on the surface of the concrete tunnels. Some areas have been inspected; however, the condition of other areas is unknown. Experience from historical inspections with remote controlled vehicles will be discussed along with the current challenge of inspecting levels below available access points. The area of interest in the exhaust tunnel must be accessed through a 14 X 14 inch concrete plug in the floor of the hot gang valve corridor. The purpose for the inspection is to determine the condition of the inside of the air tunnel and establish if there are any structural concerns. Various landmarks, pipe hangers and exposed rebar are used as reference points for the structural engineers when evaluating the current integrity of the air tunnel.

  16. PRA PERANCANGAN KAPAL PARIWISATA DI GREEN CANYON PANGANDARAN

    Directory of Open Access Journals (Sweden)

    Parlindungan Manik

    2014-05-01

    Full Text Available Kapal yang akan dirancang sebagai pengembangan pariwisata di objek wisata Green Canyon dan daerah sungai Cijulang harus memperhitungkan ukuran utama, rencana garis, rencana umum, analisa hidrostatik, stabilitas kapal dan analisis olah gerak kapal, serta pemilihan peralatan penyelamatan dan motor induk berdasarkan hasil perhitungan daya motor sesuai dengan hambatan yang dialami kapal, sehingga sarana pariwisata yang dirancang memiliki image yang baik karena sangat mengutamakan faktor keamanan dan kenyamanan penumpang. Metode perancangan kapal pariwisata ini menggunakan kapal pembanding sebagai acuannya, dengan lambung kapal berbentuk katamaran, agar menambah kesan keselamatan, keamanan dan kenyamanan penumpang. Setelah ukuran utama didapatkan maka analisa kelayakan lambung bisa didapatkan dari software pendukung perancangan kapal. Ukuran utama yang dihasilkan dari perhitungan adalah Lwl: 9,50 m, B: 4,00 m, T: 0,6 m, H: 1,5 m. Kapal pariwisata ini menggunakan dua buah tenaga penggerak berupa diesel outboard motors dengan daya yang dihasilkan sebesar 20 HP. Pada tinjauan stabilitas, hasil menunjukkan nilai GZ terbesar dan periode oleng tercepat terjadi pada saat kapal standby. Pada tinjauan olah gerak kapal pariwisata ini memiliki olah gerak yang baik terbukti tidak terjadi deck weaknes. Kemudian pada hasil gambar rencana umum, kapal memiliki space yang cukup untuk menampung penumpang lebih banyak, menata peralatan keselamatan, peralatan komunikasi dan navigasi

  17. Outbreak of leptospirosis among canyoning participants, Martinique, 2011.

    Science.gov (United States)

    Hochedez, P; Escher, M; Decoussy, H; Pasgrimaud, L; Martinez, R; Rosine, J; Théodose, R; Bourhy, P; Picardeau, M; Olive, C; Ledrans, M; Cabie, A

    2013-05-02

    Two gendarmes who participated in canyoning activities on 27 June 2011 on the Caribbean island of Martinique were diagnosed with leptospirosis using quantitative real-time polymerase chain reaction (qPCR), 9 and 12 days after the event. Among the 45 participants who were contacted, 41 returned a completed questionnaire, of whom eight met the outbreak case definition. The eight cases sought medical attention and were given antibiotics within the first week after fever onset. No severe manifestations of leptospirosis were reported. In seven of the eight cases, the infection was confirmed by qPCR. Three pathogenic Leptospira species, including L. kmetyi, were identified in four of the cases. None of the evaluated risk factors were statistically associated with having developed leptospirosis. Rapid diagnostic assays, such as qPCR, are particularly appropriate in this setting – sporting events with prolonged fresh-water exposure – for early diagnosis and to help formulate public health recommendations. Participants in such events should be made specifically aware of the risk of leptospirosis, particularly during periods of heavy rainfall and flooding.

  18. Tracer Flux Balance at an Urban Canyon Intersection

    Science.gov (United States)

    Carpentieri, Matteo; Robins, Alan G.

    2010-05-01

    Despite their importance for pollutant dispersion in urban areas, the special features of dispersion at street intersections are rarely taken into account by operational air quality models. Several previous studies have demonstrated the complex flow patterns that occur at street intersections, even with simple geometry. This study presents results from wind-tunnel experiments on a reduced scale model of a complex but realistic urban intersection, located in central London. Tracer concentration measurements were used to derive three-dimensional maps of the concentration field within the intersection. In combination with a previous study (Carpentieri et al., Boundary-Layer Meteorol 133:277-296, 2009) where the velocity field was measured in the same model, a methodology for the calculation of the mean tracer flux balance at the intersection was developed and applied. The calculation highlighted several limitations of current state-of-the-art canyon dispersion models, arising mainly from the complex geometry of the intersection. Despite its limitations, the proposed methodology could be further developed in order to derive, assess and implement street intersection dispersion models for complex urban areas.

  19. Trouble Brewing in San Francisco. Policy Brief

    Science.gov (United States)

    Buck, Stuart

    2010-01-01

    The city of San Francisco will face enormous budgetary pressures from the growing deficits in public pensions, both at a state and local level. In this policy brief, the author estimates that San Francisco faces an aggregate $22.4 billion liability for pensions and retiree health benefits that are underfunded--including $14.1 billion for the city…

  20. The timing of sediment transport down Monterey Submarine Canyon, offshore California

    Science.gov (United States)

    Stevens, Thomas; Paull, Charles K.; Ussler, William III; McGann, Mary; Buylaert, Jan-Pieter; Lundsten, Eve M

    2013-01-01

    While submarine canyons are the major conduits through which sediments are transported from the continents out into the deep sea, the time it takes for sediment to pass down through a submarine canyon system is poorly constrained. Here we report on the first study to couple optically stimulated luminescence (OSL) ages of quartz sand deposits and accelerator mass spectrometry 14C ages measured on benthic foraminifera to examine the timing of sediment transport through the axial channel of Monterey Submarine Canyon and Fan, offshore California. The OSL ages date the timing of sediment entry into the canyon head while the 14C ages of benthic foraminifera record the deposition of hemipelagic sediments that bound the sand horizons. We use both single-grain and small (∼2 mm area) single-aliquot regeneration approaches on vibracore samples from fining-upward sequences at various water depths 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 (from 14C ages of benthic foraminifera in bracketing hemipelagic sediments) are interpreted as indicating that the sand does not pass through the entire canyon instantly in large individual events, but rather moves multiple times before emerging onto the fan. The increased spread in single-grain OSL dates with water depth provides evidence of mixing and temporary storage of sediment as it moves through the canyon system. The ages also indicate that the frequency of sediment transport events decreases with distance down the canyon channel system. The amalgamated sands near the canyon head yield OSL ages that are consistent with a sub-decadal recurrence frequency while the fining-upward sand sequences on the fan indicate that the channel is still experiencing events with a 150

  1. Biodiversity of macrofaunal assemblages from three Portuguese submarine canyons (NE Atlantic)

    Science.gov (United States)

    Cunha, Marina R.; Paterson, Gordon L. J.; Amaro, Teresa; Blackbird, Sabena; de Stigter, Henko C.; Ferreira, Clarisse; Glover, Adrian; Hilário, Ana; Kiriakoulakis, Konstadinos; Neal, Lenka; Ravara, Ascensão; Rodrigues, Clara F.; Tiago, Áurea; Billett, David S. M.

    2011-12-01

    The macrofaunal assemblages from three Portuguese submarine canyons, Nazaré, Cascais and Setúbal were studied from samples collected at their upper (900-1000 m), middle (3200-3500 m) and lower sections (4200-4500 m) and at the adjacent open slopes (˜1000 m), during the HERMES cruises D297 (R.R.S. Discovery, 2005) CD179 (R.R.S. Charles Darwin, 2006) and 64PE252 (R.V. Pelagia, 2006). The taxonomic composition and patterns in biodiversity, abundance and community structure of the benthic macrofauna were described. Annelida (42.1% of total abundance; 137 species) and Arthropoda (20.6%; 162 species) were, respectively, the most abundant and the most species-rich Phyla among the 342 taxa identified during this study. Multivariate analyses showed significant differences between and within canyons and between canyons and open slope assemblages. At their upper section, canyons supported higher macrofauna abundance but slightly lower biodiversity than the adjacent slopes at similar depth. In all canyons abundance reached the highest value in the middle section and the lowest in the upper section, with marked fluctuations in Nazaré (474-4599 ind. m -2) and lower variability in Cascais (583-1125 ind. m -2). The high abundance and dominance of the assemblages in the middle section of Nazaré and Setúbal was accompanied by depressed biodiversity, while in Cascais, Hurlbert's expected species richness showed increasing values from the upper to the middle canyon, and maintained the high values at the lower section. Overall, the Nazaré Canyon showed the lowest expected species richness (ES (100): 16-39) and the Cascais Canyon the highest (39-54). There was a significant negative Kendall's correlation between total organic carbon concentrations in the superficial sediments and ES (100) and a significant positive correlation between total nitrogen and macrofauna density. The influences of organic enrichment, sediment heterogeneity and hydrodynamic regime on the abundance

  2. 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.

  3. Colorado River fish monitoring in Grand Canyon, Arizona; 2000 to 2009 summary

    Science.gov (United States)

    Makinster, Andrew S.; Persons, William R.; Avery, Luke A.; Bunch, Aaron J.

    2010-01-01

    Long-term fish monitoring in the Colorado River below Glen Canyon Dam is an essential component of the Glen Canyon Dam Adaptive Management Program (GCDAMP). The GCDAMP is a federally authorized initiative to ensure that the primary mandate of the Grand Canyon Protection Act of 1992 to protect resources downstream from Glen Canyon Dam is met. The U.S. Geological Survey's Grand Canyon Monitoring and Research Center is responsible for the program's long-term fish monitoring, which is implemented in cooperation with the Arizona Game and Fish Department, U.S. Fish and Wildlife Service, SWCA Environmental Consultants, and others. Electrofishing and tagging protocols have been developed and implemented for standardized annual monitoring of Colorado River fishes since 2000. In 2009, sampling occurred throughout the river between Lees Ferry and Lake Mead for 38 nights over two trips. During the two trips, scientists captured 6,826 fish representing 11 species. Based on catch-per-unit-effort, salmonids (for example, rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta)) increased eightfold between 2006 and 2009. Flannelmouth sucker (Catostomus latipinnis) catch rates were twice as high in 2009 as in 2006. Humpback chub (Gila cypha) catches were low throughout the 10-year sampling period.

  4. 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.

  5. Study on the wind field and pollutant dispersion in street canyons using a stable numerical method

    Institute of Scientific and Technical Information of China (English)

    XIA Ji-yang; Dennis Y.C.LEUNG

    2005-01-01

    A stable finite element method for the time dependent Navier-Stokes equations was used for studying the wind flow and pollutant dispersion within street canyons. A three-step fractional method was used to solve the velocity field and the pressure field separately from the governing equations. The Streamline Upwind Petrov-Galerkin (SUPG) method was used to get stable numerical results. Numerical oscillation was minimized and satisfactory results can be obtained for flows at high Reynolds numbers. Simulating the flow over a square cylinder within a wide range of Reynolds numbers validates the wind field model. The Strouhal numbers obtained from the numerical simulation had a good agreement with those obtained from experiment. The wind field model developed in the present study is applied to simulate more complex flow phenomena in street canyons with two different building configurations. The results indicated that the flow at rooftop of buildings might not be assumed parallel to the ground as some numerical modelers did. A counter-clockwise rotating vortex may be found in street canyons with an inflow from the left to right. In addition, increasing building height can increase velocity fluctuations in the street canyon under certain circumstances, which facilitate pollutant dispersion. At high Reynolds numbers, the flow regimes in street canyons do not change with inflow velocity.

  6. 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.

  7. 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.

  8. Late Miocene-Pleistocene evolution of a Rio Grande rift subbasin, Sunshine Valley-Costilla Plain, San Luis Basin, New Mexico and Colorado

    Science.gov (United States)

    Ruleman, C.A.; Thompson, R.A.; Shroba, R.R.; Anderson, M.; Drenth, B.J.; Rotzien, J.; Lyon, J.

    2013-01-01

    The Sunshine Valley–Costilla Plain, a structural subbasin of the greater San Luis Basin of the northern Rio Grande rift, is bounded to the north and south by the San Luis Hills and the Red River fault zone, respectively. Surficial mapping, neotectonic investigations, geochronology, and geophysics demonstrate that the structural, volcanic, and geomorphic evolution of the basin involves the intermingling of climatic cycles and spatially and temporally varying tectonic activity of the Rio Grande rift system. Tectonic activity has transferred between range-bounding and intrabasin faults creating relict landforms of higher tectonic-activity rates along the mountain-piedmont junction. Pliocene–Pleistocene average long-term slip rates along the southern Sangre de Cristo fault zone range between 0.1 and 0.2 mm/year with late Pleistocene slip rates approximately half (0.06 mm/year) of the longer Quaternary slip rate. During the late Pleistocene, climatic influences have been dominant over tectonic influences on mountain-front geomorphic processes. Geomorphic evidence suggests that this once-closed subbasin was integrated into the Rio Grande prior to the integration of the once-closed northern San Luis Basin, north of the San Luis Hills, Colorado; however, deep canyon incision, north of the Red River and south of the San Luis Hills, initiated relatively coeval to the integration of the northern San Luis Basin. Long-term projections of slip rates applied to a 1.6 km basin depth defined from geophysical modeling suggests that rifting initiated within this subbasin between 20 and 10 Ma. Geologic mapping and geophysical interpretations reveal a complex network of northwest-, northeast-, and north-south–trending faults. Northwest- and northeast-trending faults show dual polarity and are crosscut by north-south– trending faults. This structural model possibly provides an analog for how some intracontinental rift structures evolve through time.

  9. Contemporaneous trachyandesitic and calc-alkaline volcanism of the Huerto Andesite, San Juan Volcanic Field, Colorado, USA

    Science.gov (United States)

    Parat, F.; Dungan, M.A.; Lipman, P.W.

    2005-01-01

    Locally, voluminous andesitic volcanism both preceded and followed large eruptions of silicic ash-flow tuff from many calderas in the San Juan volcanic field. The most voluminous post-collapse lava suite of the central San Juan caldera cluster is the 28 Ma Huerto Andesite, a diverse assemblage erupted from at least 5-6 volcanic centres that were active around the southern margins of the La Garita caldera shortly after eruption of the Fish Canyon Tuff. These andesitic centres are inferred, in part, to represent eruptions of magma that ponded and differentiated within the crust below the La Garita caldera, thereby providing the thermal energy necessary for rejuvenation and remobilization of the Fish Canyon magma body. The multiple Huerto eruptive centres produced two magmatic series that differ in phenocryst mineralogy (hydrous vs anhydrous assemblages), whole-rock major and trace element chemistry and isotopic compositions. Hornblende-bearing lavas from three volcanic centres located close to the southeastern margin of the La Garita caldera (Eagle Mountain - Fourmile Creek, West Fork of the San Juan River, Table Mountain) define a high-K calc-alkaline series (57-65 wt % SiO2) that is oxidized, hydrous and sulphur rich. Trachyandesitic lavas from widely separated centres at Baldy Mountain-Red Lake (western margin), Sugarloaf Mountain (southern margin) and Ribbon Mesa (20 km east of the La Garita caldera) are mutually indistinguishable (55-61 wt % SiO2); they are characterized by higher and more variable concentrations of alkalis and many incompatible trace elements (e.g. Zr, Nb, heavy rare earth elements), and they contain anhydrous phenocryst assemblages (including olivine). These mildly alkaline magmas were less water rich and oxidized than the hornblende-bearing calc-alkaline suite. The same distinctions characterize the voluminous precaldera andesitic lavas of the Conejos Formation, indicating that these contrasting suites are long-term manifestations of San Juan

  10. 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

  11. 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 for...

  12. Seismic depth conversion problems associated with the Mississippi Canyon in the vicinity of Ewing Bank Block 305 field, offshore Louisiana

    Energy Technology Data Exchange (ETDEWEB)

    Leveille, G.P. (Conoco Inc., New Orleans, LA (USA)); Sahai, K.S.; McDaniel, P.G.

    1990-05-01

    Ewing Bank Block 305 field is located on the outermost edge of the continental shelf, approximately 145 km south of New Orleans, Louisiana. The geology of the field is fairly typical of other fields found offshore of Louisiana, except there is a huge, partly filled, Pleistocene submarine canyon that overlies the field. This canyon, which is commonly referred to as the Mississippi Canyon, causes a large seismic depth conversion problem that makes it virtually impossible to correctly map the structure of the field using normally processed marine seismic data The Mississippi Canyon is a large erosional feature that was formed at the mouth of the ancestral Mississippi River during the last glacial sea level lowstand. In the vicinity of the field, the canyon is about 10 km wide and 1 km deep, which is approximately two-thirds the size of the Grand Canyon of the Colorado River, and is filled mostly with Holocene sediments. Because the sediments that fill the canyon are very young, their interval velocities are much lower than the interval velocities of the sediments that form the canyon walls. This creates abrupt near surface lateral velocity variations that distort the geometry of seismic reflectors such that the time geometries seen on seismic lines are not at all indicative of the structure of the subsurface. Using a model-based processing technique and available well control, the authors have been able to solve this difficult depth conversion problem and have gained a better understanding of the geology of this field.

  13. A new model for turbidity current behavior based on integration of flow monitoring and precision coring in a submarine canyon

    Science.gov (United States)

    Symons, William O.; Sumner, Esther J.; Paull, Charles K.; Cartigny, Matthieu J.B.; Xu, Jingping; Maier, Katherine L.; Lorenson, Thomas; Talling, Peter J.

    2017-01-01

    Submarine turbidity currents create some of the largest sediment accumulations on Earth, yet there are few direct measurements of these flows. Instead, most of our understanding of turbidity currents results from analyzing their deposits in the sedimentary record. However, the lack of direct flow measurements means that there is considerable debate regarding how to interpret flow properties from ancient deposits. This novel study combines detailed flow monitoring with unusually precisely located cores at different heights, and multiple locations, within the Monterey submarine canyon, offshore California, USA. Dating demonstrates that the cores include the time interval that flows were monitored in the canyon, albeit individual layers cannot be tied to specific flows. There is good correlation between grain sizes collected by traps within the flow and grain sizes measured in cores from similar heights on the canyon walls. Synthesis of flow and deposit data suggests that turbidity currents sourced from the upper reaches of Monterey Canyon comprise three flow phases. Initially, a thin (38–50 m) powerful flow in the upper canyon can transport, tilt, and break the most proximal moorings and deposit chaotic sands and gravel on the canyon floor. The initially thin flow front then thickens and deposits interbedded sands and silty muds on the canyon walls as much as 62 m above the canyon floor. Finally, the flow thickens along its length, thus lofting silty mud and depositing it at greater altitudes than the previous deposits and in excess of 70 m altitude.

  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

    ... 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, LLC (transferee) filed an application for the transfer of license for the Stevenson No. 2 Project (FERC No....

  15. Age and diet of fossil California condors in Grand Canyon, Arizona

    Energy Technology Data Exchange (ETDEWEB)

    Emslie, S.D.

    1987-08-14

    A dozen new radiocarbon dates, together with a thorough review of its fossil distribution, shed new light on the time and probable cause of extinction of the California condor, Gymnogyps californianus, in Grand Canyon, Arizona. The radiocarbon data indicate that this species became extinct in Grand Canyon, and other parts of the inland West, more than 10,000 years ago in coincidence with the extinction of megafauna (proboscidians, edentates, perissodactyls). That condors relied on the megafauna for food is suggested by the recovery of food bones from a late Pleistocene nest cave in Grand Canyon. These fossil data have relevance to proposed release and recovery programs of the present endangered population of California condors. 19 references, 1 figure, 2 tables.

  16. 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.

  17. 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.

  18. Physical linkages between an offshore canyon and surf zone morphologic change

    Science.gov (United States)

    Hansen, Jeff E.; Raubenheimer, Britt; Elgar, Steve; List, Jeffrey H.; Lippmann, Thomas C.

    2017-04-01

    The causes of surf zone morphologic changes observed along a sandy beach onshore of a submarine canyon were investigated using field observations and a numerical model (Delft3D/SWAN). Numerically simulated morphologic changes using four different sediment transport formulae reproduce the temporal and spatial patterns of net cross-shore integrated (between 0 and 6.5 m water depths) accretion and erosion observed in a ˜300 m alongshore region, a few hundred meters from the canyon head. The observations and simulations indicate that the accretion or erosion results from converging or diverging alongshore currents driven primarily by breaking waves and alongshore pressure gradients. The location of convergence or divergence depends on the direction of the offshore waves that refract over the canyon, suggesting that bathymetric features on the inner shelf can have first-order effects on short-term nearshore morphologic change.

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. Structural character of the northern segment of the Paintbrush Canyon fault, Yucca Mountain, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Dickerson, R.P. [Science Applications International Corp., Golden, CO (United States); Spengler, R.W. [Geological Survey, Denver, CO (United States)

    1994-12-31

    Detailed mapping of exposed features along the northern part of the Paintbrush Canyon fault was initiated to aid in construction of the computer-assisted three-dimensional lithostratigraphic model of Yucca Mountain, to contribute to kinematic reconstruction of the tectonic history of the Paintbrush Canyon fault, and to assist in the interpretation of geophysical data from Midway Valley. Yucca Mountain is segmented into relatively intact blocks of east-dipping Miocene volcanic strata, bounded by north-striking, west-dipping high-angle normal faults. The Paintbrush Canyon fault, representing the easternmost block-bounding normal fault, separates Fran Ridge from Midway Valley and continues northward across Yucca Wash to at least the southern margin of the Timber Mountain Caldera complex. South of Yucca Wash, the Paintbrush Canyon Fault is largely concealed beneath thick Quaternary deposits. Bedrock exposures to the north reveal a complex fault, zone, displaying local north- and west-trending grabens, and rhombic pull-apart features. The fault scarp, discontinuously exposed along a mapped length of 8 km north of Yucca Wash, dips westward by 41{degrees} to 74{degrees}. Maximum vertical offset of the Rhyolite of Comb Peak along the fault measures about 210 m in Paintbrush Canyon and, on the basis of drill hole information, vertical offset of the Topopoah Spring Tuff is about 360 m near the northern part of Fran Ridge. Observed displacement along the fault in Paintbrush Canyon is down to the west with a component of left-lateral oblique slip. Unlike previously proposed tectonic models, strata adjacent to the fault dip to the east. Quaternary deposits do not appear displaced along the fault scarp north of Yucca Wash, but are displaced in trenches south of Yucca Wash.

  4. Cold-Water Corals and Anthropogenic Impacts in La Fonera Submarine Canyon Head, Northwestern Mediterranean Sea.

    Directory of Open Access Journals (Sweden)

    Galderic Lastras

    Full Text Available We assess the occurrence and extent of cold-water coral (CWC species Madrepora oculata and Dendrophyllia cornigera, as well as gorgonian red coral Corallium rubrum, in La Fonera canyon head (Northwestern Mediterranean Sea, as well as human impacts taking place in their habitats. Occurrence is assessed based on Remotely Operated Vehicle (ROV video imaging. Terrain classification techniques are applied to high-resolution swath bathymetric data to obtain semi-automatic interpretative maps to identify the relationship between coral distribution patterns and canyon environments. A total of 21 ROV immersions were carried out in different canyon environments at depths ranging between 79 and 401 m. Large, healthy colonies of M. oculata occur on abrupt, protected, often overhanging, rocky sections of the canyon walls, especially in Illa Negra branch. D. cornigera is sparser and evenly distributed at depth, on relatively low sloping areas, in rocky but also partially sedimented areas. C. rubrum is most frequent between 100 and 160 m on highly sloping rocky areas. The probable extent of CWC habitats is quantified by applying a maximum entropy model to predict habitat suitability: 0.36 km2 yield M. oculata occurrence probabilities over 70%. Similar predictive models have been produced for D. cornigera and C. rubrum. All ROV transects document either the presence of litter on the seafloor or pervasive trawling marks. Nets and longlines are imaged entangled on coral colonies. Coral rubble is observed at the foot of impacted colonies. Some colonies are partially covered by sediment that could be the result of the resuspension generated by bottom trawling on neighbouring fishing grounds, which has been demonstrated to be responsible of daily increases in sediment fluxes within the canyon. The characteristics of the CWC community in La Fonera canyon are indicative that it withstands high environmental stress of both natural and human origin.

  5. Canyons within the slope of the Bohemian Massif created subsequent to the meteorite impact at the end of the Mesozoic

    Energy Technology Data Exchange (ETDEWEB)

    Jiricek, Rudolf [Moravian Oil Co., Hodonin (Czech Republic)

    1996-12-31

    The origin of the deep canyons both in south Moravia and in Lower Austria is attributed to major sea-level changes, possibly caused by the Late Cretaceous-Early Tertiary meteorite impact at Chicxulub (Mexico) and also to the contemporaneous uplift of the Bohemian Massif (Czech Republic). The canyons were eroded by river activity during the Bohemian Massif uplift at the time of the global sea-level fall. The Nesvacilka Canyon was eroded to a depth of 2000 m, which is comparable to the Grand Canyon of the Colorado River. The deep erosion penetrated through the Cretaceous and Jurassic sediments into the Palaeozoic formations and/or the granitoid basement. The canyons have been filled with Palaeogene marine sediments, which are up to 1400 m thick. (author)

  6. Small angle neutron scattering (SANS and V-SANS) study of asphaltene aggregates in crude oil.

    Science.gov (United States)

    Headen, Thomas F; Boek, Edo S; Stellbrink, Jörg; Scheven, Ulrich M

    2009-01-06

    We report small angle neutron scattering (SANS) experiments on two crude oils. Analysis of the high-Q SANS region has probed the asphaltene aggregates in the nanometer length scale. We find that the radius of gyration decreases with increasing temperature. We show that SANS measurements on crude oils give similar aggregate sizes to those found from SANS measurements of asphaltenes redispersed in deuterated toluene. The combined use of SANS and V-SANS on crude oil samples has allowed the determination of the radius of gyration of large scale asphaltene aggregates of approximately 0.45 microm. This has been achieved by the fitting of Beaucage functions over two size regimes. Analysis of the fitted Beaucage functions at very low-Q has shown that the large scale aggregates are not simply made by aggregation of all the smaller nanoaggregates. Instead, they are two different aggregates coexisting.

  7. Support for the Astronomically Calibrated 40Ar/39Ar Age of Fish Canyon Sanidine

    DEFF Research Database (Denmark)

    Rivera, Tiffany; Storey, Michael; Zeeden, Christian

    2011-01-01

    Fish Canyon sanidine (FCs) is the neutron fluence monitor most widely used in Cenozoic argon geochronology. Recommend published ages for FCs have been determined through various intercalibration techniques, but have varied by up to 2% over the last three decades. The robust quality of the astrono......Fish Canyon sanidine (FCs) is the neutron fluence monitor most widely used in Cenozoic argon geochronology. Recommend published ages for FCs have been determined through various intercalibration techniques, but have varied by up to 2% over the last three decades. The robust quality...

  8. Linking aerosol fluxes in street canyons to urban city-scale emissions

    Directory of Open Access Journals (Sweden)

    B. K. Tay

    2009-09-01

    Full Text Available In this study we investigate ultrafine particle (UFP fluxes using a first order eddy viscosity turbulence closure Computational Fluid Dynamics (CFD model and determine the different factors that influence emissions of UFP into the urban boundary layer. Both vertical turbulent fluxes as well as the fluxes due to mean flow are shown to contribute to the overall ventilation characteristics of street canyons. We then derive a simple parameterised numerical prediction model for canyon top UFP venting which is then compared with tower based micrometeorological flux measurements obtained during the REPARTEE and CityFlux field experiments.

  9. Southwestern riparian plant trait matrix, Colorado River, Grand Canyon, 2014 to 2016 - Data

    Science.gov (United States)

    Palmquist, Emily C.; Ralston, Barbara; Sarr, Daniel; Merritt, David M.; Shafroth, Patrick B.; Scott, J. A.

    2016-01-01

    This dataset contains information on the physical traits and environmental tolerances of plant species occurring along the lower Colorado River through Grand Canyon. Due to the unique combination of plant species within the Grand Canyon, this flora shares species with many riparian areas in the western U.S.A. and represents obligate wetland to obligate upland plant species. Data for the matrix were compiled from published scientific papers, unpublished reports, plant fact sheets, existing trait databases, regional floras, and plant guides. Categorical, ordinal, and continuous data are included in this dataset. This dataset does not contain sensitive or classified data.

  10. Vertical tectonic deformation associated with the San Andreas fault zone offshore of San Francisco, California

    Science.gov (United States)

    Ryan, H. F.; Parsons, T.; Sliter, R. W.

    2008-10-01

    A new fault map of the shelf offshore of San Francisco, California shows that faulting occurs as a distributed shear zone that involves many fault strands with the principal displacement taken up by the San Andreas fault and the eastern strand of the San Gregorio fault zone. Structures associated with the offshore faulting show compressive deformation near where the San Andreas fault goes offshore, but deformation becomes extensional several km to the north off of the Golden Gate. Our new fault map serves as the basis for a 3-D finite element model that shows that the block between the San Andreas and San Gregorio fault zone is subsiding at a long-term rate of about 0.2-0.3 mm/yr, with the maximum subsidence occurring northwest of the Golden Gate in the area of a mapped transtensional basin. Although the long-term rates of vertical displacement primarily show subsidence, the model of coseismic deformation associated with the 1906 San Francisco earthquake indicates that uplift on the order of 10-15 cm occurred in the block northeast of the San Andreas fault. Since 1906, 5-6 cm of regional subsidence has occurred in that block. One implication of our model is that the transfer of slip from the San Andreas fault to a fault 5 km to the east, the Golden Gate fault, is not required for the area offshore of San Francisco to be in extension. This has implications for both the deposition of thick Pliocene-Pleistocene sediments (the Merced Formation) observed east of the San Andreas fault, and the age of the Peninsula segment of the San Andreas fault.

  11. Dynamics of the Bingham Canyon rock avalanches (Utah, USA) resolved from topographic, seismic, and infrasound data: Bingham Canyon Rock Avalanches

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Jeffrey R. [Department of Geology and Geophysics, University of Utah, Salt Lake City Utah USA; Pankow, Kristine L. [Department of Geology and Geophysics, University of Utah, Salt Lake City Utah USA; Ford, Sean R. [Atmospheric, Earth, and Energy Division, Lawrence Livermore National Laboratory, Livermore California USA; Koper, Keith D. [Department of Geology and Geophysics, University of Utah, Salt Lake City Utah USA; Hale, J. Mark [Department of Geology and Geophysics, University of Utah, Salt Lake City Utah USA; Aaron, Jordan [Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver British Columbia Canada; Larsen, Chris F. [Geophysical Institute, University of Alaska Fairbanks, Fairbanks Alaska USA

    2017-03-01

    The 2013 Bingham Canyon Mine rock avalanches represent one of the largest cumulative landslide events in recorded U.S. history and provide a unique opportunity to test remote analysis techniques for landslide characterization. Here we combine aerial photogrammetry surveying, topographic reconstruction, numerical runout modeling, and analysis of broadband seismic and infrasound data to extract salient details of the dynamics and evolution of the multiphase landslide event. Our results reveal a cumulative intact rock source volume of 52 Mm3, which mobilized in two main rock avalanche phases separated by 1.5 h. We estimate that the first rock avalanche had 1.5–2 times greater volume than the second. Each failure initiated by sliding along a gently dipping (21°), highly persistent basal fault before transitioning to a rock avalanche and spilling into the inner pit. The trajectory and duration of the two rock avalanches were reconstructed using runout modeling and independent force history inversion of intermediate-period (10–50 s) seismic data. Intermediate- and shorter-period (1–50 s) seismic data were sensitive to intervals of mass redirection and constrained finer details of the individual slide dynamics. Back projecting short-period (0.2–1 s) seismic energy, we located the two rock avalanches within 2 and 4 km of the mine. Further analysis of infrasound and seismic data revealed that the cumulative event included an additional 11 smaller landslides (volumes ~104–105 m3) and that a trailing signal following the second rock avalanche may result from an air-coupled Rayleigh wave. Our results demonstrate new and refined techniques for detailed remote characterization of the dynamics and evolution of large landslides.

  12. Wind tunnel simulation of pollutant dispersion inside street canyons with galle- ries and multi-level flat roofs

    Institute of Scientific and Technical Information of China (English)

    黄远东; 曾宁斌; 刘泽宇; 宋也; 许璇

    2016-01-01

    In this study, the pollutant dispersion within street canyons is studied by experiments conducted in an environmental wind tunnel. The vehicular exhaust emissions are modeled using a line source. The pollutant (smoke) concentrations inside the canyons are measured based on a light scattering technique. The pollutant concentrations within the four different street canyons containing the galleries and the three-level flat-roofs under both the isolated and urban environments are obtained and discussed. For each of the four canyon configurations investigated, it is found that there is an obvious discrepancy between the pollutant dispersion patterns under the isolated environment and the urban environment. The three-level flat roof is found to significantly influence the pollutant distribution pattern in a street canyon. In order to clarify the impacts of the wedge-shaped roofs on the pollutant dispersion inside an urban street canyon of an aspect ratio of 1.0, the pollutant distributions inside urban street canyons of three different wedge-shaped roof combinations are measured and analyzed. It is revealed that the pollutant distribution pattern inside the urban street canyon of an aspect ratio of 1.0 is influenced greatly by the wedge-shaped roof,especially, when an upward wedge-shaped roof is placed on the upstream building of the canyon. Images from this study may be utilized for a rough evaluation of the computational fluid dynamics (CFD) models and for helping architects and urban planners to select the canyon configurations with a minimum negative impact on the local air quality.

  13. 75 FR 55270 - Safety Zone; NASSCO Launching of USNS Washington Chambers, San Diego Bay, San Diego, CA

    Science.gov (United States)

    2010-09-10

    ... Chambers, San Diego Bay, San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone on the navigable waters of the San Diego Bay in... the Port (COTP) San Diego or his designated representative. DATES: This rule is effective from 9:15 a...

  14. Description of gravity cores from San Pablo Bay and Carquinez Strait, San Francisco Bay, California

    Science.gov (United States)

    Woodrow, Donald L.; John L. Chin,; Wong, Florence L.; Fregoso, Theresa; Jaffe, Bruce E.

    2017-06-27

    Seventy-two gravity cores were collected by the U.S. Geological Survey in 1990, 1991, and 2000 from San Pablo Bay and Carquinez Strait, California. The gravity cores collected within San Pablo Bay contain bioturbated laminated silts and sandy clays, whole and broken bivalve shells (mostly mussels), fossil tube structures, and fine-grained plant or wood fragments. Gravity cores from the channel wall of Carquinez Strait east of San Pablo Bay consist of sand and clay layers, whole and broken bivalve shells (less than in San Pablo Bay), trace fossil tubes, and minute fragments of plant material.

  15. San Luis Valley waterbird plan : Draft

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The goal of this plan is "to provide and protect a habitat base of sufficient quality and quantity to maintain healthy viable populations of waterbirds in the San...

  16. Historical methyl mercury in San Francisco Bay

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — San Francisco Bay, California is considered a mercury-impaired watershed. Elevated concentrations of mercury are found in water and sediment as well as fish and...

  17. Bathymetry--Offshore of San Francisco, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetry and shaded-relief maps of Offshore of San Francisco, California (raster data file is included in...

  18. Backscatter A [8101]--Offshore San Gregorio, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of SIM 3306 presents data for the acoustic-backscatter map (see sheet 3, SIM 3306) of the Offshore of San Gregorio map area, California. Backscatter data...

  19. Habitat--Offshore of San Francisco, 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 Offshore of San Francisco map area, California. The vector data file is included in...

  20. San Antonio Bay 1986-1989

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The effect of salinity on utilization of shallow-water nursery habitats by aquatic fauna was assessed in San Antonio Bay, Texas. Overall, 272 samples were collected...

  1. Habitat--Offshore of San Francisco, 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 Offshore of San Francisco map area, California. The vector data file is included in...

  2. Contours--Offshore of San Francisco, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetric contours for several seafloor maps of the Offshore of San Francisco map area, California. The vector data file...

  3. Backscatter B [7125]--Offshore San Gregorio, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of SIM 3306 presents data for the acoustic-backscatter map (see sheet 3, SIM 3306) of the Offshore of San Gregorio map area, California. Backscatter data...

  4. San Bernardino National Wildlife Refuge contaminant study

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The San Bernardino National Wildlife Refuge was established in 1982 for the protection and management of endangered desert fishes which are indigenous to the Rio...

  5. An Archeological Survey of the San Diego River

    Science.gov (United States)

    1975-08-27

    Indian populations and to arable landa and water, Father Serra moved Mission San Diego de Aleala ------ to the site of Nipoguay, an Indian village located...NN ARCHAEOLOGICAL SRE OF THE ~i7 SAN DIEGORIE I If SAN DIEGO STATE UNIVERSITY FOUNDATION DEPARTMENT OF THE ARMY, CORPS OF ENGINEERS kSAN DIEGO STATE...the San Diego River Archeological Survey A. PERFORMING ORG.ý REPORT NUM§ER na 7. AUTHOR(s) 6. CONTRACT OR GRANT NUMBER(*) - I- PERFORMING ORGANIZATION

  6. Adaptive Management of Glen Canyon Dam: Two Decades of Large Scale Experimental Treatments Intended to Benefit Resources of the Colorado River in Grand Canyon, USA

    Science.gov (United States)

    Melis, Theodore

    2010-05-01

    Glen Canyon Dam was closed in 1963, primarily to store water for the rapidly developing southwestern United States. The dam's hydropower plant, with a generating capacity of up to 1,300 megawatts of electrical energy, was initially operated without daily peaking constraints from 1966 to 1990, resulting in daily tides on the Colorado River through Grand Canyon National Park of up to 4 meters. The influences of Glen Canyon Dam's peaking operations on downstream river resources through Grand Canyon have been intensively studied for nearly four decades. Following experimental reoperation of the dam in summer 1990, and five years of studies associated with a major environmental impact statement, the Glen Canyon Dam Adaptive Management Program was created in 1997, to evaluate whether a new experimental flow regime, combined with other non-flow treatments, can mitigate the detrimental effects of the former hydropeaking flow regime. Experimental flow treatments associated with the program over the last two decades have included the adoption of hourly and daily operating rules that now govern and constrain hydropeaking, periodic release of experimental controlled floods to rebuild sandbar habitats along shorelines and occasional steady flow tests intended to benefit the river's endangered humpback chub; one of the endemic fish of the Colorado River basin that experienced a population decline following dam closure. Other non-flow experimental treatments being evaluated by the program include removal of nonnative fish species, such as rainbow trout and other exotic fish, as well as translocation of humpback chub into other habitats below the dam where they might successfully spawn. Since 1995, three controlled flood experiments have been released from the dam to determine whether the remaining sand supplies that enter the Colorado River below the dam (about 6 to 16 percent of the predam sand supply) can be managed to create and maintain sandbar habitats used by humpback chub

  7. 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

  8. SSC San Diego Strategic Plan. Revision 3

    Science.gov (United States)

    2001-11-01

    OMB control number. 1. REPORT DATE NOV 2001 2. REPORT TYPE 3. DATES COVERED - 4. TITLE AND SUBTITLE SSC San Diego Strategic Plan. Rev 3 5a...Business Improvement Group ( CBIG ), will be composed of the team members listed above, and will be responsible for monitoring the planning and...implementation of these objectives. The CBIG will charter sub-groups as necessary. Improve Corporate IT infrastructure Much of the SSC San Diego IT service

  9. Trouble Brewing in San Diego. Policy Brief

    Science.gov (United States)

    Buck, Stuart

    2010-01-01

    The city of San Diego will face enormous budgetary pressures from the growing deficits in public pensions, both at a state and local level. In this policy brief, the author estimates that San Diego faces total of $45.4 billion, including $7.95 billion for the county pension system, $5.4 billion for the city pension system, and an estimated $30.7…

  10. 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

  11. Bioavailability of sinking organic matter in the Blanes canyon and the adjacent open slope (NW Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    P. Lopez-Fernandez

    2013-05-01

    Full Text Available Submarine canyons are sites of intense energy and material exchange between the shelf and the deep adjacent basins. To test the hypothesis that active submarine canyons represent preferential conduits of available food for the deep-sea benthos, two mooring lines were deployed at 1200 m depth from November 2008 to November 2009 inside the Blanes canyon and on the adjacent open slope (Catalan Margin, NW Mediterranean Sea. We investigated the fluxes, biochemical composition and food quality of sinking organic carbon (OC. OC fluxes in the canyon and the open slope varied among sampling periods, though not consistently in the two sites. In particular, while in the open slope the highest OC fluxes were observed in August 2009, in the canyon the highest OC fluxes occurred in April–May 2009. For almost the entire study period, the OC fluxes in the canyon were significantly higher than those in the open slope, whereas OC contents of sinking particles collected in the open slope were consistently higher than those in the canyon. This result confirms that submarine canyons are effective conveyors of OC to the deep sea. Particles transferred to the deep sea floor through the canyons are predominantly of inorganic origin, significantly higher than that reaching the open slope at a similar water depth. Using multivariate statistical tests, two major clusters of sampling periods were identified: one in the canyon that grouped trap samples collected in December 2008, concurrently with the occurrence of a major storm at the sea surface, and associated with increased fluxes of nutritionally available particles from the upper shelf. Another cluster grouped samples from both the canyon and the open slope collected in March 2009, concurrently with the occurrence of the seasonal phytoplankton bloom at the sea surface, and associated with increased fluxes of total phytopigments. Our results confirm the key ecological role of submarine canyons for the functioning of

  12. Low-altitude aerial color digital photographic survey of the San Andreas Fault

    Science.gov (United States)

    Lynch, David K.; Hudnut, Kenneth W.; Dearborn, David S.P.

    2010-01-01

    Ever since 1858, when Gaspard-Félix Tournachon (pen name Félix Nadar) took the first aerial photograph (Professional Aerial Photographers Association 2009), the scientific value and popular appeal of such pictures have been widely recognized. Indeed, Nadar patented the idea of using aerial photographs in mapmaking and surveying. Since then, aerial imagery has flourished, eventually making the leap to space and to wavelengths outside the visible range. Yet until recently, the availability of such surveys has been limited to technical organizations with significant resources. Geolocation required extensive time and equipment, and distribution was costly and slow. While these situations still plague older surveys, modern digital photography and lidar systems acquire well-calibrated and easily shared imagery, although expensive, platform-specific software is sometimes still needed to manage and analyze the data. With current consumer-level electronics (cameras and computers) and broadband internet access, acquisition and distribution of large imaging data sets are now possible for virtually anyone. In this paper we demonstrate a simple, low-cost means of obtaining useful aerial imagery by reporting two new, high-resolution, low-cost, color digital photographic surveys of selected portions of the San Andreas fault in California. All pictures are in standard jpeg format. The first set of imagery covers a 92-km-long section of the fault in Kern and San Luis Obispo counties and includes the entire Carrizo Plain. The second covers the region from Lake of the Woods to Cajon Pass in Kern, Los Angeles, and San Bernardino counties (151 km) and includes Lone Pine Canyon soon after the ground was largely denuded by the Sheep Fire of October 2009. The first survey produced a total of 1,454 oblique digital photographs (4,288 x 2,848 pixels, average 6 Mb each) and the second produced 3,762 nadir images from an elevation of approximately 150 m above ground level (AGL) on the

  13. Abrupt along-strike change in tectonic style: San Andreas Fault zone, San Francisco Peninsula

    Science.gov (United States)

    Zoback, Mary Lou; Jachens, Robert C.; Olson, Jean A.

    1999-05-01

    Seismicity and high-resolution aeromagnetic data are used to define an abrupt change from compressional to extensional tectonism within a 10- to 15-km-wide zone along the San Andreas fault on the San Francisco Peninsula and offshore from the Golden Gate. This 100-km-long section of the San Andreas fault includes the hypocenter of the Mw = 7.8 1906 San Francisco earthquake as well as the highest level of persistent microseismicity along that ˜470-km-long rupture. We define two distinct zones of deformation along this stretch of the fault using well-constrained relocations of all post-1969 earthquakes based a joint one-dimensional velocity/hypocenter inversion and a redetermination of focal mechanisms. The southern zone is characterized by thrust- and reverse-faulting focal mechanisms with NE trending P axes that indicate "fault-normal" compression in 7- to 10-km-wide zones of deformation on both sides of the San Andreas fault. A 1- to 2-km-wide vertical zone beneath the surface trace of the San Andreas is characterized by its almost complete lack of seismicity. The compressional deformation is consistent with the young, high topography of the Santa Cruz Mountains/Coast Ranges as the San Andreas fault makes a broad restraining left bend (˜10°) through the southernmost peninsula. A zone of seismic quiescence ˜15 km long separates this compressional zone to the south from a zone of combined normal-faulting and strike-slip-faulting focal mechanisms (including a ML = 5.3 earthquake in 1957) on the northernmost peninsula and offshore on the Golden Gate platform. Both linear pseudogravity gradients, calculated from the aeromagnetic data, and seismic reflection data indicate that the San Andreas fault makes an abrupt ˜3-km right step less than 5 km offshore in this northern zone. A similar right-stepping (dilatational) geometry is also observed for the subparallel San Gregorio fault offshore. Persistent seismicity and extensional tectonism occur within the San Andreas

  14. 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

  15. 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.

  16. The Foote House (10-AA-96), An Historic Archaeological Complex in the Boise River Canyon, Idaho.

    Science.gov (United States)

    1982-01-01

    about her family’s life in the Boise River canyon, and that personal note is appreciated. Diana Rigg and Christin Fuhrman provided assistance with the...than a passing -: interest in the lady [Paul 1976:31. Thus, the Lydle Gulch stone foundations have significance in terms of both Arthur De Wint and Mary

  17. 36 CFR 7.8 - Sequoia and Kings Canyon National Parks.

    Science.gov (United States)

    2010-07-01

    ... National Parks. 7.8 Section 7.8 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.8 Sequoia and Kings Canyon National Parks. (a) Dogs and cats. Dogs and cats are prohibited on any park land or trail except within...

  18. Macrofaunal density and biomass in the Campeche Canyon, Southwestern Gulf of Mexico

    Science.gov (United States)

    Escobar Briones, Elva; Estrada Santillán, Erika Laura; Legendre, Pierre

    2008-12-01

    The composition, density and community structure of the benthic macrofauna were investigated in sediments of the Campeche Canyon in the SW Gulf of Mexico. Total macrofaunal density ranged from 9466±2736 ind m -2 at the continental shelf station to 1550±195 ind m -2 in the canyon. Density values significantly diminished with distance from the coast and depth; only a few stations in the center of the canyon displayed larger density values (E-37 with 4666±1530 ind m -2, E-36 with 5791±642 ind m -2 and E-26 with 6925±2258 ind m -2). Densities were positively correlated to organic nitrogen in the sediment ( r=0.82) and coarse silt ( r=0.43), and negatively with depth ( r=-0.74) and distance from the coast ( r=-0.68). At all stations, the polychaete worms contributed most to the multi-species community structure. The nematodes and Foraminifera displayed their highest densities in the center of the canyon. The biomass values declined significantly with depth. We conclude that the macrofauna density and biomass changed in response to organic matter contents in the sediment, both with distance from the coast and with depth.

  19. 75 FR 439 - Glen Canyon Dam Adaptive Management Work Group (AMWG)

    Science.gov (United States)

    2010-01-05

    ... Plan and Socio-economic workshops, updates from the public outreach ad hoc group, and a report from the... Decision on the Operation of Glen Canyon Dam Final Environmental Impact Statement to comply with... environmental assessment that will be used to evaluate the effects of the protocol. Other agenda items...

  20. Sedimentation in Rio La Venta Canyon in Netzahualcoyotl Reservoir, Chiapas, Mexico

    Science.gov (United States)

    Juan Antonio de la Fuente; Tom Lisle; Jose Velasquez; Bonnie L. Allison; Alisha Miller

    2000-01-01

    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.

  1. 81 FR 16198 - Deer Flat National Wildlife Refuge, Canyon, Payette, Owyhee, and Washington Counties, ID, and...

    Science.gov (United States)

    2016-03-25

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Fish and Wildlife Service Deer Flat National Wildlife Refuge, Canyon, Payette, Owyhee, and Washington..., 1010 Dearborn St., Caldwell, ID 83605. Homedale Public Library, 125 W Owyhee Ave., Homedale, ID...

  2. 61 FR 11863 - Vehicle Management Area Designation and Road Closure Order; Ada, Elmore, Canyon, and Owyhee...

    Science.gov (United States)

    1996-03-22

    ... Vehicle Management Area Designation and Road Closure Order; Ada, Elmore, Canyon, and Owyhee Counties, ID... except for those portions of the NCA currently included within the Owyhee Front Special Recreation... Bruneau, Kuna, and Owyhee Management Framework Plans, and the Jarbidge Resource Management Plan....

  3. 61 FR 11862 - Shooting Closures and Restrictions in Ada, Canyon, Elmore, and Owyhee Counties, ID

    Science.gov (United States)

    1996-03-22

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Shooting Closures and Restrictions in Ada, Canyon, Elmore, and Owyhee Counties, ID AGENCY: Bureau of Land... Bruneau, Kuna, and Owyhee Management Framework Plans. Violation of this order is punishable by a fine...

  4. 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...

  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

    Pollution Model (OSPM) and Computational Fluid Dynamics (CFD) code FLUENT. All models disregarded any particle dynamics. CFD simulations have been carried out in a simplified geometry of the selected street canyon. Four different sizes of emission sources have been used in the CFD simulations to assess...

  6. Tectonic Implications of Canyon Directions Over the Northeast Atlantic Continental Margin

    Science.gov (United States)

    Lallemand, Serge; Sibuet, Jean-Claude

    1986-12-01

    The basis of this study is a new bathymetric map of the northeast Atlantic compiled from previously published maps made from conventional echosounder data, plus all Sea Beam data acquired on board the R/V JEAN CHARCOT since 1977. As most of the Sea Beam data have been obtained on the continental margin from Porcupine Seabight to the south of the Iberian Peninsula, a precise picture of the continental slope is given. A statistical analysis of the canyons, based on 750 measurements, reveals that many of the canyons present sharp changes in their direction, indicating a structural control mainly linked to the late Hercynian trends, especially around the Iberian Peninsula. Nevertheless, the paths of canyons may merely reflect recent gravity processes, as in the Porcupine Seabight. Canyons locally follow the directions of listric and associated transecting faults (Permian to Triassic and upper Jurassic to lower Cretaceous), as on the Celtic margin, and every type of tectonic lineament—for example, the North Pyrenean Paleogene thrust front which fringes the Gouf of Cap Breton. A comparison of diagrams for the northern and southern Bay of Biscay margin (especially trends predating the opening) is compatible with a 25° rotation of Iberia with respect to Europe.

  7. 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.

  8. Fault tree analysis of the F&H Canyon Exhaust Systems at the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Low, J.M.; Marshall, K.M.

    1993-10-01

    The Canyon Exhaust System (CES) for the F&H Canyon chemical Separations Facilities are considered safety class items (SCIs). SCIs are defined in DOE Order 6430.1A as systems, components, and structures, including portions of process systems, whose failure could adversely affect the environment or safety and health of the public. As such, any modification to SCIs must be carefully reviewed for impact to safety. During the last year, the Savannah River Technology Center of WSRC has been requested to perform two major evolutions on the Canyon Exhaust Systems. These evaluations include an Upgrade to Canyon Exhaust System (UCES) Project for both F&H Areas and a Backfit analysis for a standby diesel generator in F-Area. The purpose of the first evaluation was to evaluate the impact of cost reduction options on the UCES reliability. The purpose of the second analysis was to provide justification for not upgrading an existing standby diesel generator to meet current safety class standards.

  9. Biodiversity of macrofaunal assemblages from three Portuguese submarine canyons (NE Atlantic)

    NARCIS (Netherlands)

    Cunha, M.R.; Paterson, G.L.J.; Amaro, T.; Blackbird, S.; de Stigter, H.C.; Ferreira, C.; Glover, A.; Hilário, A.; Kiriakoulakis, K.; Neal, L.; Ravara, A.; Rodrigues, C.F.; Tiago, A.; Billett, D.S.M.

    2011-01-01

    The macrofaunal assemblages from three Portuguese submarine canyons, Nazare, Cascais and Setubal were studied from samples collected at their upper (900-1000 m), middle (3200-3500 m) and lower sections (4200-4500 m) and at the adjacent open slopes (similar to 1000 m), during the HERMES cruises D297

  10. The Influence of Dam Discharge Regime and Canyon Orientation on Ecosystem Metabolism in the Colorado River

    Science.gov (United States)

    Kennedy, T. A.; Tietjen, T.; Wright, S.

    2005-05-01

    Since the closure of Glen Canyon Dam and the beginning of flow regulation of the Colorado River in Grand Canyon in 1963, considerable efforts have been directed toward understanding the aquatic ecology of this altered ecosystem. Understanding what controls resource availability has been a central focus of these efforts because the Colorado River supports populations of sport fish and endangered humpback chub, both of which appear to be strongly resource limited. There is evidence that dam discharge regime and canyon orientation influence algal standing crop due to their effects on water velocity (scour) and solar insolation, respectively. We explored whether these physical factors influenced rates of primary production and ecosystem respiration, two different metrics of resource availability, in the clear tailwater section of the Colorado River by conducting whole system metabolism measurements across a range of discharge regimes and in reaches with different orientation (i.e. N-S vs. E-W). We found that while both discharge regime and canyon orientation influence rates of primary production, seasonal changes in light availability appear to have a far stronger influence on rates of primary production in the Colorado River. Water temperature appeared to be the main driver of ecosystem respiration.

  11. 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..., photography, jogging, bicycling, on- leash dog walking, and horseback riding. No additional trail or lake.... Gotts Point would be opened to vehicular traffic upon completion of a cooperative agreement with...

  12. 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.

    depression with step-like micro-terraces running in NNE–SSW direction. The depth to the seafloor topography varies from 900 to 1459 m with 100-150 m thick levee sediments deposited on both the edges of the canyon as seafloor swells spreading over a distance...

  13. BathymetryA Hillshade [2m]--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 2-m and 5-m bathymetry and shaded-relief maps of Monterey Canyon and Vicinity, California. The raster data file is included in...

  14. BathymetryB [5m]--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 2-m and 5-m bathymetry and shaded-relief maps of Monterey Canyon and Vicinity, California. The raster data file is included in...

  15. BathymetryA [2m]--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 2-m and 5-m bathymetry and shaded-relief maps of Monterey Canyon and Vicinity, California. The raster data file is included in...

  16. Deposition rates, mixing intensity and organic content in two contrasting submarine canyons

    NARCIS (Netherlands)

    García, R.; Van Oevelen, D.; Soetaert, K.E.R.; Thomsen, L.; De Stigter, H.C.; Epping, E.

    2008-01-01

    The hydrographically different conditions characterising the Western Iberian Margin (NE Atlantic) and the Gulf of Lions (Mediterranean) may play an important role in determining the biogeochemical characteristics of the sediments. To investigate this, we compared the Nazaré and Cap de Creus canyons,

  17. 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

  18. 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.

  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. Supporting Evidence for the Astronomically Calibrated Age of Fish Canyon Sanidine

    DEFF Research Database (Denmark)

    Rivera, Tiffany; Storey, Michael; Zeeden, Christian

    The relative nature of the 40Ar/39Ar radio-isotopic dating technique requires that the age and error of the monitor mineral be accurately known. The most widely accepted monitor for Cenozoic geochronology is the Fish Canyon sanidine (FCs), whose recommended published ages have varied by up to 2...

  1. A Refined Astronomically Calibrated 40Ar/39Ar Age for Fish Canyon Sanidine

    DEFF Research Database (Denmark)

    Rivera, Tiffany; Storey, Michael; Zeeden, Christian

    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 Fish Canyon sanidine (FCs) neutron fluence...

  2. 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

    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 of ra...... of a uniform size generate more complex patterns, including peaks, plateaus, canyons, and craters of species richness....

  3. Diagenetic alteration process of chlorite in Tyr Member sandstone, Siri Canyon, Danish North Sea

    DEFF Research Database (Denmark)

    Kazerouni, Afsoon Moatari; Friis, Henrik; Hansen, Jens Peter Vind

    To evaluate the possible changes in petrology within the reservoir sand and across the oil water contact in Rau-1A, Siri Canyon Danish North Sea, 18 samples were selected and studied mainly by electron microscope and XRD. The major diagenetic phases in the well are micro quartz, large syntaxial...

  4. BathymetryB Hillshade [5m]--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 2-m and 5-m bathymetry and shaded-relief maps of Monterey Canyon and Vicinity, California. The raster data file is included in...

  5. 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:...

  6. 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,

  7. 78 FR 42902 - Safety Zone; Olympus Tension Leg Platform, Mississippi Canyon Block 807, Outer Continental Shelf...

    Science.gov (United States)

    2013-07-18

    ... Canyon Block 807, Outer Continental Shelf on the Gulf of Mexico AGENCY: Coast Guard, DHS. ACTION: Notice.... Department of Transportation, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE... federal holidays. The telephone number is 202-366-9329. See the ``Public Participation and Request for...

  8. Anthropogenic impacts on deep submarine canyons of the western Mediterranean Sea

    Science.gov (United States)

    Sanchez-Vidal, A.; Tubau, X.; Llorca, M.; Woodall, L.; Canals, M.; Farré, M.; Barceló, D.; Thompson, R.

    2016-02-01

    Submarine canyons are seafloor geomorphic features connecting the shallow coastal ocean to the deep continental margin and basin. Often considered biodiversity hotspots, submarine canyons have been identified as preferential pathways for water, sediment, pollutant and litter transfers from the coastal to the deep ocean. Here we provide insights on the presence of some of the most insidious man-made debris and substances in submarine canyons of the western Mediterranean Sea, which are relevant to achieve a "Good Environmental Status" by 2020 as outlined in the European Union's ambitious Marine Strategy Framework Directive. Ranked by size on a decreasing basis, we review the origin, distribution and transport mechanisms of i) marine litter, including plastic, lost fishing gear and metallic objects; ii) microplastics in the form of fibers of rayon, polyester, polyamide and acetates; and iii) persistent organic pollutants including the toxic and persistent perfluoroalkyl substances. This integrated analysis allows us to understand the pivotal role of atmospheric driven oceanographic processes occurring in Mediterranean deep canyons (dense shelf water cascading, coastal storms) in spreading any type of man-made compound to the deep sea, where they sink and accumulate before getting buried.

  9. 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.

  10. Safety analysis, 200 Area, Savannah River Plant H-Canyon operations. Supplement 5

    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 [Science Applications International Corp., San Diego, CA (United States)

    1986-02-01

    The H-Canyon facility is located in the 200 Separations Area and uses the HM process to separate uranium, neptunium, plutonium, and fission products. Irradiated uranium fuels containing {sup 235}U at enrichments from 1.1% to 94% are processed and recovered, along with neptunium and plutonium isotopes. This Safety Analysis Report (SAR) documents an analysis of the H-Canyon operations and is an update to a section of a previous SAR. This SAR documents an analysis of the H-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 H-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 H-Carbon can be operated without due risk to onsite or offsite populations and to the environment. In this report, risk is defined an the expected frequency of an accident, multiplied by the resulting radiological consequence in person-rem. The units of risk for radiological does are person-rem/year. Maximum individual exposure values have also been calculated and reported.

  11. Probabilistic Hazard of Tsunamis Generated by Submarine Landslides in the Cook Strait Canyon (New Zealand)

    Science.gov (United States)

    Lane, Emily M.; Mountjoy, Joshu J.; Power, William L.; Mueller, Christof

    2016-12-01

    Cook Strait Canyon is a submarine canyon that lies within ten kilometres of Wellington, the capital city of New Zealand. The canyon walls are covered with scars from previous landslides which could have caused local tsunamis. Palaeotsunami evidence also points to past tsunamis in the Wellington region. Furthermore, the canyon's location in Cook Strait means that there is inhabited land in the path of both forward- and backward-propagating waves. Tsunamis induced by these submarine landslides pose hazard to coastal communities and infrastructure but major events are very uncommon and the historical record is not extensive enough to quantify this hazard. The combination of infrequent but potentially very consequential events makes realistic assessment of the hazard challenging. However, information on both magnitude and frequency is very important for land use planning and civil defence purposes. We use a multidisciplinary approach bringing together geological information with modelling to construct a Probabilistic Tsunami Hazard Assessment of submarine landslide-generated tsunami. Although there are many simplifying assumptions used in this assessment, it suggests that the Cook Strait open coast is exposed to considerable hazard due to submarine landslide-generated tsunamis. We emphasise the uncertainties involved and present opportunities for future research.

  12. 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.

  13. 77 FR 35671 - Conformed Power Marketing Criteria or Regulations for the Boulder Canyon Project

    Science.gov (United States)

    2012-06-14

    ... Area Power Administration Conformed Power Marketing Criteria or Regulations for the Boulder Canyon Project AGENCY: Western Area Power Administration, DOE. ACTION: Conformance of power marketing criteria in... (Western), a Federal power marketing agency of the Department of Energy (DOE), is modifying Part C of...

  14. BathymetryA Hillshade [2m]--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 2-m and 5-m bathymetry and shaded-relief maps of Monterey Canyon and Vicinity, California. The raster data file is included in...

  15. BathymetryB [5m]--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 2-m and 5-m bathymetry and shaded-relief maps of Monterey Canyon and Vicinity, California. The raster data file is included in...

  16. BathymetryB Hillshade [5m]--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 2-m and 5-m bathymetry and shaded-relief maps of Monterey Canyon and Vicinity, California. The raster data file is included in...

  17. BathymetryA [2m]--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 2-m and 5-m bathymetry and shaded-relief maps of Monterey Canyon and Vicinity, California. The raster data file is included in...

  18. 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.

  19. 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

  20. 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.

  1. 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

  2. Hudson Canyon benthic habitats characterization and mapping by integrated analysis of multidisciplinary data

    Science.gov (United States)

    Pierdomenico, Martina; Guida, Vincent G.; Rona, Peter A.; Macelloni, Leonardo; Scranton, Mary I.; Asper, Vernon; Diercks, Arne

    2013-04-01

    Hudson Canyon, about 180 km SE of New York City, is the largest eastern U.S. submarine canyon and is under consideration for HAPC (Habitat Area of Particular Concern) status, representing a fisheries and biodiversity hot spot. Interest in the area, within the perspective of ecosystem based management, marine spatial planning, habitat and species conservation, led to a joint project between NOAA Northeast Fisheries, U.S. Geological Survey (USGS), Mississippi Mineral Research Institute (MMRI), National Institute for Undersea Science and Technology (NIUST), Stony Brook and Rutgers Universities for the study of benthic habitats, that includes the assembly of existing data with newly collected ones: acoustic mapping, visual ground-truthing, hydrographic, sedimentological, and trawl data collections. Acoustic mapping, performed using AUV-mounted multibeam sonar, provided ultra-high resolution bathymetric and backscatter imagery (3m and 1m respectively) at all water depths for identification of geomorphological features and for the characterization of surficial sediments along the two thirds of the shelf portion of the canyon. Identification of benthic and demersal communities was accomplished by visual ground thruthing with underwater vehicle video and still cameras, and from trawl catch data. A CTD-rosette sampler provided water column salinity-temperature profiles and water samples for dissolved methane analysis in the vicinity of suspected bottom sources. Analysis of data revealed a complex of topographic structures and hydrological patterns that provide a wide range of physical habitats in a relatively small area. A mosaic of sandy and muddy substrates, gravel beds, rock outcrops, and semilithified clay outcrops host rich and varied faunal assemblages, including deepwater corals and sponge communities. Pockmark fields, occurring below 300 m depth, suggest that methane-based chemosynthetic carbonate deposition contributes to creation of specific hard bottom habitats

  3. Mapping the True 3D Morphology of Deep-Sea Canyons

    Science.gov (United States)

    Huvenne, V. A.; Masson, D.; Tyler, P. A.; Huehnerbach, V.

    2010-12-01

    The importance of submarine canyons as ecosystem hotspots and sediment transport pathways has been recognised for decades (e.g. Heezen et al., 1955; Vetter & Dayton, 1998). However, studying canyon systems in detail is a challenge, because of the complexity and steepness of the terrain. Acoustic surveys are hampered by side-echoes, while the high slope angles cause most types of sampling equipment, deployed from surface vessels, to fail. Ship-borne bathymetric surveys tend to represent the canyon topography in an overly smoothed way as a result of their limited resolution in deep water compared to the scale of the terrain variability. Moreover, it is clear that overhanging cliffs cannot be mapped correctly with traditional, downward looking multibeam echosounders. The increasing availability of underwater vehicles, however, opens new opportunities. During summer 2009, we mapped several submarine canyon habitats in detail, using the UK deep-water Remotely Operated Vehicle (ROV) ISIS. In particular, we developed a new methodology to map vertical cliffs and overhangs by placing the high-resolution Simrad SM2000 multibeam system of the ROV in a forward-looking position rather than in the traditional downward-looking configuration. The cliff morphology was then mapped by moving the ROV laterally in parallel passes at different depths. Repeating this approach at different distances from the cliff face, we obtained maps of varying resolution and extent. The low resolution maps provide an overview of the general geological framework, while individual strata and faunal colonies can be recognised on the highest resolution maps. Using point-cloud models, we combined the ship-borne bathymetry with the ROV-based data, in order to obtain a true 3D seabed morphology of the canyon study site, which can be used for fly-throughs, geomorphological analysis or habitat mapping. With this approach, we could visualise the spatial structure and density distribution of a unique and

  4. Synthesis of SAN-PB-SAN triblock copolymers via a ''living'' copolymerization with macro-photoiniferters

    NARCIS (Netherlands)

    Kroeze, E; de Boer, B.; ten Brinke, G.; Hadziioannou, G

    1996-01-01

    A technique is described for the synthesis of poly((styrene-co-acrylonitrile)-block-butadiene-block-(styrene-co-acrylonitrile)) (SAN-PB-SAN) triblock copolymers through polybutadiene-based photo-iniferters. Dihydroxy- and dicarboxy-terminated polybutadienes were transformed into the chloro-terminate

  5. 76 FR 1386 - Safety Zone; Centennial of Naval Aviation Kickoff, San Diego Bay, San Diego, CA

    Science.gov (United States)

    2011-01-10

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Centennial of Naval Aviation Kickoff, San... in support of the Centennial of Naval Aviation Kickoff. This temporary safety zone is necessary to... Purpose On February 12, 2010, the Centennial of Naval Aviation Kickoff will take place in San Diego Bay...

  6. 77 FR 59969 - Notice of Inventory Completion: San Francisco State University, Department of Anthropology, San...

    Science.gov (United States)

    2012-10-01

    ... Anthropology, San Francisco, CA; Correction AGENCY: National Park Service, Interior. ACTION: Notice; correction... Department of Anthropology). The human remains and associated funerary objects were removed from Marin County... San Francisco State University Department of Anthropology records. In the Federal Register (73...

  7. Una Visita al Viejo San Juan (A Visit to Old San Juan).

    Science.gov (United States)

    Cabello, Victor; And Others

    Written in Spanish, this black and white illustrated booklet provides a tour of Old San Juan, Puerto Rico's oldest and most historic city. Brief historical information is provided on the Perro de San Jeronimo, a statue of a barking dog found in front of the Castillo; Plaza de Colon, a small plaza dedicated to Christopher Columbus; the Catedral de…

  8. Una Visita al Viejo San Juan (A Visit to Old San Juan).

    Science.gov (United States)

    Cabello, Victor; And Others

    Written in Spanish, this black and white illustrated booklet provides a tour of Old San Juan, Puerto Rico's oldest and most historic city. Brief historical information is provided on the Perro de San Jeronimo, a statue of a barking dog found in front of the Castillo; Plaza de Colon, a small plaza dedicated to Christopher Columbus; the Catedral de…

  9. 33 CFR 165.754 - Safety Zone: San Juan Harbor, San Juan, PR.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zone: San Juan Harbor, San Juan, PR. 165.754 Section 165.754 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and...

  10. Sediment delivery by ungaged tributaries of the Colorado River in Grand Canyon, Arizona

    Science.gov (United States)

    Webb, Robert H.; Griffiths, Peter G.; Melis, Theodre S.; Hartley, Daniel R.

    2000-01-01

    Sediment input to the Colorado River in Grand Canyon, Arizona, is a valuable resource required to sustain both terrestrial and aquatic ecosystems. A total of 768 ungaged tributaries deliver sediment to the river between Glen Canyon Dam and the Grand Wash Cliffs (river miles -15 to 276). The 32 tributaries between the dam and Lee's Ferry produce only streamflow floods, whereas 736 tributaries in Grand Canyon produce streamflow floods and debris flows. We used three techniques to estimate annual streamflow sediment yield from ungaged tributaries to the Colorado River. For the Glen Canyon and Marble Canyon reaches (river miles -15 to 61.5), respectively, these techniques indicate that 0.065.106 and 0.610.106 Mg/yr (0.68.106 Mg/yr of total sediment) enters the river. This amount is 20 percent of the sediment yield of the Paria River, the only gaged tributary in this reach and a major sediment contributor to the Colorado River. The amount of sand delivered ranges from 0.10.106 to 0.51.106 Mg/yr, depending on the sand content of streamflow sediment. Sand delivered in Glen Canyon is notably coarser (D50 = 0.24 mm) than sand in other reaches (D50 = 0.15 mm). A relation is given for possible variation of this sediment delivery with climate. Debris flows transport poorly-sorted sediment onto debris fans in the Colorado River. In the pre-dam era, debris fans were completely reworked during Colorado River floods, liberating all fine-grained sediment to the river; in the post-dam river on average only 25 percent of debris-fan volume is reworked, leading to storage of sand in the matrix of debris fans. We develop a sediment-yield model for debris flows that uses a logistic-regression model of debris-flow frequency in Grand Canyon, a regression model of debris-flow volumes, particle- size distributions of intact debris-flow deposits, and debris-fan reworking. On average, debris flows deliver between 0.14.106 and 0.30.106 Mg/yr of sediment to debris fans throughout Grand Canyon

  11. Magnitude and frequency data for historic debris flows in Grand Canyon National Park and vicinity, Arizona

    Science.gov (United States)

    Melis, T.S.; Webb, R.H.; Griffiths, P.G.; Wise, T.J.

    1995-01-01

    Debris flows occur in 529 tributaries of the Colorado River in Grand Canyon between Lees Ferry and Diamond Creek, Arizona (river miles 0 to 225). An episodic type of flash flood, debris flows transport poorly-sorted sediment ranging in size from clay to boulders into the Colorado River. Debris flows create and maintain debris fans and the hundreds of associated riffles and rapids that control the geomorphic framework of the Colorado River downstream from Glen Canyon Dam. Between 1984 and 1994, debris flows created 4 new rapids and enlarged 17 existing rapids and riffles. Debris flows in Grand Canyon are initiated by slope failures that occur during intense rainfall. Three of these mechanisms of slope failure are documented. Failures in weathered bedrock, particularly in the Hermit Shale and Supai Group, have initiated many historic debris flows in Grand Canyon. A second mechanism, termed the fire-hose effect, occurs when runoff pours over cliffs onto unconsolidated colluvial wedges, triggering a failure. A third initiation mechanism occurs when intense precipitation causes failures in colluvium overlying bedrock. Multiple source areas and extreme topographic relief in Grand Canyon commonly result in combinations of these three initiation mechanisms. Interpretation of 1,107 historical photographs spanning 120 years, supplemented with aerial photography made between 1935 and 1994, yielded information on the frequency of debris flows in 168 of the 529 tributaries (32 percent) of the Colorado River in Grand Canyon. Of the 168 tributaries, 96 contain evidence of debris flows that have occurred since 1872, whereas 72 tributaries have not had a debris flow during the last century. The oldest debris flow we have documented in Grand Canyon occurred 5,400 years ago in an unnamed tributary at river mile 63.3-R. Our results indicate that the frequency of debris flows ranges from one every 10 to 15 years in certain eastern tributaries, to less than one per century in other

  12. 78 FR 19103 - Safety Zone; Spanish Navy School Ship San Sebastian El Cano Escort; Bahia de San Juan; San Juan, PR

    Science.gov (United States)

    2013-03-29

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Spanish Navy School Ship San Sebastian El... during the transit of the Spanish Navy School Ship San Sebastian El Cano, a public vessel, and during... board the Spanish Navy School Ship San Sebastian El Cano. The inbound escort is scheduled to take...

  13. Benthic polychaete diversity patterns and community structure in the Whittard Canyon system and adjacent slope (NE Atlantic)

    Science.gov (United States)

    Gunton, Laetitia M.; Neal, Lenka; Gooday, Andrew J.; Bett, Brian J.; Glover, Adrian G.

    2015-12-01

    We examined deep-sea macrofaunal polychaete species assemblage composition, diversity and turnover in the Whittard Canyon system (NE Atlantic) using replicate megacore samples from three of the canyon branches and one site on the continental slope to the west of the canyon, all at ~3500 m water depth. A total of 110 polychaete species were recorded. Paramphinome jeffreysii was the most abundant species (2326 ind. m-2) followed by Aurospio sp. B (646 ind. m-2), Opheliidae sp. A (393 ind. m-2), Prionospio sp. I (380 ind. m-2), and Ophelina abranchiata (227 ind. m-2). Species composition varied significantly across all sites. From west to east, the dominance of Paramphinome jeffreysii increased from 12.9% on the slope to 39.6% in the Eastern branch. Ordination of species composition revealed that the Central and Eastern branches were most similar, whereas the Western branch and slope sites were more distinct. High abundances of P. jeffreysii and Opheliidae sp. A characterised the Eastern branch of the canyon and may indicate an opportunistic response to a possible recent input of organic matter inside the canyon. Species richness and diversity indices were higher on the slope compared with inside the canyon, and the slope site had higher species evenness. Within the canyon, species diversity between branches was broadly similar. Despite depressed diversity within the canyon compared with the adjacent slope, the fact that 46 of the 99 polychaete species found in the Whittard Canyon were not present on the adjacent slope suggests that this feature may enhance the regional species pool. However, our sampling effort on the adjacent slope was insufficient to confirm this conclusion.

  14. 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

  15. 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.

  16. 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.

  17. municipios Maracaibo y San Francisco

    Directory of Open Access Journals (Sweden)

    Rosa E. Ortiz

    2005-01-01

    Full Text Available El estudio de las Organizaciones No Gubernamentales estuvo dirigido a caracterizar la diversidad de grupos y asociaciones que bajo el termino genérico de ONG’s existen en los municipios Maracaibo y San Francisco, los más poblados y relevantes en la vida política, económica, social y cultural del estado Zulia-Venezuela. Se planteó una investigación exploratoria y descriptiva. El resultado permitió reconocer a Existe un crecimiento sostenido de las ONG en estos municipios: b los sectores con mayor concentración son el de salud; educación; deporte y recreación; arte y cultura. c Las instituciones que promueven más organizaciones son la iglesia y el Estado, lo que supone es este último caso una reducción de las funciones que le corresponden, además de la minimización de costos y conflictos laborales. d Ambivalencia en la orientación de su funcionamiento: Algunas ONG’s implementan prácticas próximas a la mercantilización de los servicios con lo cual legitiman estrategias del modelo económico neoliberal mientras otras contribuyen a fortalecer la democratización de los servicios públicos. Se concluye que el crecimiento y características de las ONGs en estos municipios estuvo vinculado en los noventa y comienzos de la década de 2000 por la aplicación de las políticas públicas neoliberales.

  18. Numerical Investigation of the Impact of Different Configurations and Aspect Ratios on Dense Gas Dispersion in Urban Street Canyons

    Institute of Scientific and Technical Information of China (English)

    YANG Rui; ZHANG Jing; SHEN Shifei; LI Xiaomeng; CHEN Jianguo

    2007-01-01

    The dispersion of chlorine gas in urban street canyons was numerically simulated using the fire dynamics simulator, a code developed by the National Institute of Standards and Technology of USA, which uses large eddy simulation coupled with the Smagorinsky sub-grid scale model. The unsteady flow fields were computed by solving the filtered incompressible Navier-Stokes equations under low Mach number approximation by the finite difference method. The studies analyzed the influence of different street canyon configurations and aspect ratios on the flow and chlorine gas dispersion. The geometric configuration and aspect ratio both affect the vortices and the local concentration distributions in street canyons.

  19. Bioavailability of sinking organic matter in the Blanes canyon and the adjacent open slope (NW Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    P. Lopez-Fernandez

    2012-12-01

    Full Text Available Submarine canyons are sites of intense energy and material exchange between the shelf and the deep adjacent basins. To test the hypothesis that active submarine canyons represent preferential conduits of available food for the deep-sea benthos, two mooring lines were deployed at 1200 m depth from November 2008 to November 2009 inside the Blanes canyon and on the adjacent open slope (Catalan Margin, NW Mediterranean Sea. We investigated the fluxes, biochemical composition and food quality of sinking organic carbon (OC. OC fluxes in the canyon and the open slope varied among sampling periods, though not consistently in the two sites. In particular, while in the open slope the highest OC fluxes were observed in August 2009, in the canyon the highest OC fluxes occurred in April–May 2009. For almost the entire study period, the OC fluxes in the canyon were significantly higher than those in the open slope, whereas OC contents of sinking particles collected in the open slope were consistently higher than those in the canyon. This result confirms that submarine canyons are effective conveyors of OC to the deep sea, particles transferred are predominantly of inorganic origin, significantly higher than that reaching the open slope at a similar water depth. Using multivariate statistical tests, two major clusters of sampling periods were identified: one in the canyon that grouped trap samples collected in December 2008, concurrently with the occurrence of a major storm at the sea surface, and associated with increased fluxes of nutritionally available particles from the upper shelf. Another cluster grouped samples from both the canyon and the open slope collected in March 2009, concurrently with the occurrence of the seasonal phytoplankton bloom at the sea surface, and associated with increased fluxes of total phytopigments. Our results confirm the key ecological role of submarine canyons for the functioning of deep-sea ecosystems, and highlight the

  20. San Pascual (2007) Año XLV, n. 344

    OpenAIRE

    2007-01-01

    Editorial. Coronación pontificia y declaración del patronato canónico para nuestra señora de Gracia. siguiendo los caminos de San Pascual, capítulo XIII Madrid II. Entrevista, Rosario García García presidenta de la asociación de hijas de María del Rosario.¡Seréis mis testigos (II)!. Donativos pro nueva bandera de San Pascual. San Pascual y la virgen de Gracia. Vida en el santuario. Los tesoros de San Pascual. Milagros de San Pascual VI, libra San Pascual a muchos del peligro del mar y de otro...

  1. San Diego Science Alliance Education Outreach Activities

    Science.gov (United States)

    Blue, Anne P.

    1996-11-01

    The General Atomics Science Education Outreach Activities as well as those of several other San Diego area institutions led to the formation in 1994 of the San Diego Science Alliance. The Science Alliance is a consortium of science-related industries, institutions of research and higher education, museums, medical health networks, and science competitions in support of K-12 science education. Some Alliance accomplishments include printing over 4000 resource catalogs for teachers, workshops presented by over 20 of their business members at the San Diego Science Education Conference, and hosting of 3 eight-week courses for teachers. The Alliance provides an important forum for interaction between schools and teachers and local industries and institutions. The Science Alliance maintains a World Wide Web Home Page at elvbf http://www.cerf.net/sd_science/. General Atomics' role in the San Diego Science Alliance will be presented.(Presented by Patricia S. Winter for the General Atomics Science Education Groups and San Diego Science Alliance.)

  2. 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

  3. Carbonate shoreline sedimentation in San Andres Formation, Lincoln County, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Hill, K.W.; Pierce, R.W.

    1986-03-01

    The Permian San Andres Formation of late Leonardian-early Guadalupian age is a significant hydrocarbon producer and crops out over a large area in south-central New Mexico. However, since its definition in 1909, the age and depositional environment of this unit have been questioned. In 1971 in Pecos County, Vincent Kelly divided the unit into three members: Rio Bonito, Bonney Canyon, and Fourmile Draw. The lowest member, although named for the Rio Bonito, has a type section designated at Sunset along U.S. Highway 70/380. Two miles east of Sunset, near Riverside, on the Rio Bonito, the Rio Bonito Member is exposed in a long series of roadcuts. Petrographic investigation of these rocks reveals an alternating sequence of high to low-energy intertidal to subtidal facies marked by oolitic and fossiliferous dolocalcarenite interbedded with dolomitic mudstone. The unit has been recrystallized and stylolites are abundant, as is dolomite and nodular mosaic anhydrite. These alternating units contain a faunal assemblage that is marked by red algae, foraminifera, bryozoa, crinoids, pelecypods, brachiopods, and cephalopods. Burrow fillings and fecal pellets are also abundant. The authors suggest that these units mark an extensive carbonate flat containing shoals and lagoons with open-marine and intertidal channels.

  4. Cacao use and the San Lorenzo Olmec.

    Science.gov (United States)

    Powis, Terry G; Cyphers, Ann; Gaikwad, Nilesh W; Grivetti, Louis; Cheong, Kong

    2011-05-24

    Mesoamerican peoples had a long history of cacao use--spanning more than 34 centuries--as confirmed by previous identification of cacao residues on archaeological pottery from Paso de la Amada on the Pacific Coast and the Olmec site of El Manatí on the Gulf Coast. Until now, comparable evidence from San Lorenzo, the premier Olmec capital, was lacking. The present study of theobromine residues confirms the continuous presence and use of cacao products at San Lorenzo between 1800 and 1000 BCE, and documents assorted vessels forms used in its preparation and consumption. One elite context reveals cacao use as part of a mortuary ritual for sacrificial victims, an event that occurred during the height of San Lorenzo's power.

  5. Food-web dynamics and isotopic niches in deep-sea communities residing in a submarine canyon and on the adjacent open slopes

    Science.gov (United States)

    Demopoulos, Amanda; McClain-Counts, Jennifer; Ross, Steve W.; Brooke, Sandra; Mienis, Furu

    2017-01-01

    Examination of food webs and trophic niches provide insights into organisms' functional ecology, yet few studies have examined trophodynamics within submarine canyons, where the interaction of canyon morphology and oceanography influences habitat provision and food deposition. Using stable isotope analysis and Bayesian ellipses, we documented deep-sea food-web structure and trophic niches in Baltimore Canyon and the adjacent open slopes in the US Mid-Atlantic Region. Results revealed isotopically diverse feeding groups, comprising approximately 5 trophic levels. Regression analysis indicated that consumer isotope data are structured by habitat (canyon vs. slope), feeding group, and depth. Benthic feeders were enriched in 13C and 15N relative to suspension feeders, consistent with consuming older, more refractory organic matter. In contrast, canyon suspension feeders had the largest and more distinct isotopic niche, indicating they consume an isotopically discrete food source, possibly fresher organic material. The wider isotopic niche observed for canyon consumers indicated the presence of feeding specialists and generalists. High dispersion in δ13C values for canyon consumers suggests that the isotopic composition of particulate organic matter changes, which is linked to depositional dynamics, resulting in discrete zones of organic matter accumulation or resuspension. Heterogeneity in habitat and food availability likely enhances trophic diversity in canyons. Given their abundance in the world's oceans, our results from Baltimore Canyon suggest that submarine canyons may represent important havens for trophic diversity.

  6. Salt Ponds, South San Francisco Bay

    Science.gov (United States)

    2002-01-01

    higher resolution 1000 pixel-wide image The red and green colors of the salt ponds in South San Francisco Bay are brilliant visual markers for astronauts. The STS-111 crew photographed the bay south of the San Mateo bridge in June, 2002. This photograph is timely because a large number of the salt ponds (more than 16,500 acres) that are owned by Cargill, Inc. will be sold in September for wetlands restoration-a restoration project second in size only to the Florida Everglades project. Rough boundaries of the areas to be restored are outlined on the image. Over the past century, more than 80% of San Francisco Bay's wetlands have been filled and developed or diked off for salt mining. San Francisco Bay has supported salt mining since 1854. Cargill has operated most of the bay's commercial salt ponds since 1978, and had already sold thousands of acres to the State of California and the Don Edwards National Wildlife Refuge. This new transaction will increase San Francisco Bay's existing tidal wetlands by 50%. The new wetlands, to be managed by the California Department of Fish and Game and the U.S. Fish and Wildlife Service, will join the Don Edwards National Wildlife Refuge, and provide valuable habitat for birds, fish and other wildlife. The wetlands will contribute to better water quality and flood control in the bay, and open up more coastline for public enjoyment. Additional information: Cargill Salt Ponds (PDF) Turning Salt Into Environmental Gold Salt Ponds on Way to Becoming Wetlands Historic Agreement Reached to Purchase San Francisco Bay Salt Ponds Astronaut photograph STS111-376-3 was provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth

  7. A Case for Historic Joint Rupture of the San Andreas and San Jacinto Faults

    Science.gov (United States)

    Lozos, J.

    2015-12-01

    The ~M7.5 southern California earthquake of 8 December 1812 ruptured the San Andreas Fault from Cajon Pass to at least as far north as Pallet Creek (Biasi et al., 2002). The 1812 rupture has also been identified in trenches at Burro Flats to the south (Yule and Howland, 2001). However, the lack of a record of 1812 at Plunge Creek, between Cajon Pass and Burro Flats (McGill et al., 2002), complicates the interpretation of this event as a straightforward San Andreas rupture. Paleoseismic records of a large early 19th century rupture on the northern San Jacinto Fault (Onderdonk et al., 2013; Kendrick and Fumal, 2005) allow for alternate interpretations of the 1812 earthquake. I use dynamic rupture modeling on the San Andreas-San Jacinto junction to determine which rupture behaviors produce slip patterns consistent with observations of the 1812 event. My models implement realistic fault geometry, a realistic velocity structure, and stress orientations based on seismicity literature. Under these simple assumptions, joint rupture of the two faults is the most common behavior. My modeling rules out a San Andreas-only rupture that is consistent with the data from the 1812 earthquake, and also shows that single fault events are unable to match the average slip per event for either fault. The choice of nucleation point affects the details of rupture directivity and slip distribution, but not the first order result that multi-fault rupture is the preferred behavior. While it cannot be definitively said that joint San Andreas-San Jacinto rupture occurred in 1812, these results are consistent with paleoseismic and historic data. This has implications for the possibility of future multi-fault rupture within the San Andreas system, as well as for interpretation of other paleoseismic events in regions of complex fault interactions.

  8. 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 and...

  9. 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...

  10. 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

    ... management of the Diablo Canyon Nuclear Power Plant's design/ licensing basis which undermines PG&E's ability... Electronic Hearing Docket webpage at http://ehd1.nrc.gov/EHD/ . The time and date of the evidentiary...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. Engaging stakeholders in global change risk and vulnerability planning: a case study of the Kruger to Canyons Biosphere Region

    CSIR Research Space (South Africa)

    Davis, C

    2010-09-01

    Full Text Available Understanding climatic changes and their possible impacts on society is essential in critical sectors in South Africa in order to improve strategic adaptation responses. The study presented here, based in the Kruger to Canyons Biosphere Region, aims...

  16. 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....

  17. 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.

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

    Science.gov (United States)

    Betancourt, J.L.; Rylander, Kate Aasen; 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 17 000 to 12 000 14C yr BP, Pinus edulis–Juniperus scopulorum woodlands dominated limestone substrates between 1800 and 1490 m, with Pseudotsugamenziesii 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 12 000 14C yr BP with the extirpation of J. scopulorum from Rough Canyon, and was completed by at least 10 54014C 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

  19. 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

  20. A Glorious Century of Art Education: San Francisco's Art Institute

    Science.gov (United States)

    Dobbs, Stephen Mark

    1976-01-01

    Author described the life and times of the San Francisco Art Institute and reviewed the forces that made San Francisco a city of more than ordinary awareness of the arts in its civic and civil existence. (Editor/RK)