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In settings where the transport of sand is partially or fully supply limited, changes in the upstream supply of sand are coupled to changes in the grain size of sand on the bed. In this manner, the transport of sand under the supply-limited case is 'grain-size regulated'. Since the closure of Glen Canyon Dam in 1963, the downstream reach of the Colorado River in Marble and Grand Canyons has exhibited evidence of sand-supply limitation. Sand transport in the river is now approximately equally regulated by changes in the discharge of water and changes in the grain sizes of sand on the channel bed and eddy sandbars. Previous work has shown that changes in the grain size of sand on the bed of the channel (driven by...
Categories: Publication; Types: Citation; Tags: Sedimentology
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The effects of wave action and horseshoe crab spawning on the topography and grain-size characteristics on the foreshore of an estuarine sand beach in Delaware Bay, New Jersey, USA were evaluated using data collected over six consecutive high tides. Data were gathered inside and outside a 25 m long exclosure constructed to create a control area free of disturbance by crabs. The density of crabs in the swash zone outside the exclosure was 8??1 organisms m-2. The maximum depth of sediment activation on the upper foreshore where spawning occurred was 0??103 m during periods characterized by low significant wave heights: < 0??08 m. This depth is greater than the depth of activation by waves alone during moderate significant...
Categories: Publication; Types: Citation; Tags: Sedimentology
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A physiographically prominent, approximately 40 square km plateau lies roughly 20 km east of Mount Spurr volcano, northwestern Cook Inlet region, Alaska, and comprises the preserved remnant of a volcaniclastic succession, designated in this study as map unit Qvc. Although this readily mappable package of volcaniclastic rocks has been recognized in numerous studies during the past five decades, uncertainties regarding its age and origin have persisted. We describe the general characteristics of the volcaniclastic plateau, provide new age constraints for deposits, present lithofacies descriptions and interpretations of the volcaniclastic strata, and synthesize our observations and lithofacies analysis to propose an...
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This dataset summarizes various sedimentary data from ten U.S. Geological Survey (USGS) surface water sites across the contiguous United States. These sites include: 01648010 Rock Creek at Joyce Road, Washington, DC 05586300 Illinois River at Florence, Illinois 06731000 Cherry Creek below Cherry Creek Lake, Colorado 06807000 Missouri River at Nebraska City, Nebraska 06935965 Missouri River at St. Charles, Missouri 08374550 Rio Grande near Castolon, Texas 08375300 Rio Grande at Rio Grande Village, Big Bend National Park, Texas 09404200 Colorado River above Diamond Creek near Peach Springs, Arizona 11447650 Sacramento River at Freeport, California 12046260 Elwha River at diversion near Port Angeles, Washington The...
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These data were collected from the TOPGUN-SODA10 2AK core collected in 2010 by LacCore (University of Minnesota), the USGS. and the University of California (U.C.) Berkeley. The 8.9 meter length core had stable isotopes of oxygen and carbon sampled every 10 millimeters or so, and diatoms samples at every 50 millimeters to 200 millimeters depending on the depth in the core. mineralogic data were collected using X-ray diffraction and grain-size analysis were done at various depths. These data are used to interpret the Holocene and late Pleistocene hydrology and paleoclimate of the lake and the region. The interpretation can be found in: Rosen, M.R., Reidy, L., Starratt, S., Zimmerman, S., in review, Middle Holocene...
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This dataset contains the model outputs from the daily Hydrological Simulation Program - FORTRAN (HSPF) model of the Sacramento River Basin, including streamflow and sediment time series from water years 1981-2099. Streamflow time series data are in cubic feet per second, sediment loads are in tons per day, and suspended sediment concentrations are in milligrams per liter.
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The 2008 - Present Ecosystem History of South Florida's Estuaries Database contains listings of all sites (modern and core) and modern monitoring site survey information (water chemistry, floral and faunal data, etc.). Two general types of data are contained within this database: 1) Modern Field Data and 2) Core data - location information. Data are available for modern sites (from 2008 to present) and cores in the general areas of Florida Bay, Biscayne Bay, and the southwest (Florida) coastal mangrove estuaries. Specific sites in the Florida Bay area include Taylor Creek, Bob Allen Key, Russell Bank, Pass Key, Whipray Basin, Rankin Bight, park Key, and Mud Creek core). Specific Biscayne Bay sites include Manatee...
Tags: 002, 004, 007, 008, 012, All tags...
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From 2008 to 2012, the U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, Walla Walla District, developed an acoustic backscatter surrogate (model 1.0) for estimating real-time suspended-sediment concentration and loads at Clearwater River at Spalding, ID (USGS ID: 13342500) using a horizontally-mounted 3000kHz acoustic Doppler velocity meter (ADVM). This study is a continuation of the 2008 to 2012 acoustic backscatter surrogate study using samples collected since 2015 to validate the continued use of model 1.0. Sample data collected in 2015 to 2018 show a deviation from model 1.0 when backscatter data from the ADVM, after correction for acoustic losses, is greater than 65.7 decibels....
Channel- and lens-shaped deposits of non-eolian red sandstone are enclosed within the eolian Leche-e Member of the Page Sandstone in south-central Utah. Detailed analysis of lithology and geometry, and regional correlation of the red sandstone deposits suggests that the channel-shaped scours and in-filling deposits were formed by ephemeral stream processes, in contrast to earlier interpretations that suggested a marine estuarine origin. We hypothesize that ephemeral streams transporting volcanic debris flowed toward the north and northeast along the western edge of the Page erg. Local avulsion, possibly caused by eolian damming of an adjacent drainage, led to stream flow into low areas of the Page erg. Entrainment...
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At the head of the Arm, decrease in percent sand of surface sediments with time and return of rodents, pulmonate gastropods, trees, bushes and grasses to the intertidal region, indicate that the rate of sediment deposition has slowed and the Upper Turnagain Arm area has returned to a state of preearthquake equilibrium only 17 years after the event. -Author
Categories: Publication; Types: Citation; Tags: Sedimentology
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Temporally and spatially averaged models of bedload transport are inadequate to describe the highly variable nature of particle motion at low transport stages. The primary sources of this variability are the resisting forces to downstream motion resulting from the geometrical relation (pocket friction angle) of a bed grain to the grains that it rests upon, variability of the near-bed turbulent velocity field and the local modification of this velocity field by upstream, protruding grains. A model of bedload transport is presented that captures these sources of variability by directly integrating the equations of motion of each particle of a simulated mixed grain-size sediment bed. Experimental data from the velocity...
Categories: Publication; Types: Citation; Tags: Sedimentology
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Episodic, large-volume pulses of volcaniclastic sediment and coseismic subsidence of the coast have influenced the development of a late Holocene delta at southern Puget Sound. Multibeam bathymetry, ground-penetrating radar (GPR) and vibracores were used to investigate the morphologic and stratigraphic evolution of the Nisqually River delta. Two fluvial–deltaic facies are recognized on the basis of GPR data and sedimentary characteristics in cores, which suggest partial emplacement from sediment-rich floods that originated on Mount Rainier. Facies S consists of stacked, sheet-like deposits of andesitic sand up to 4 m thick that are continuous across the entire width of the delta. Flat-lying, highly reflective surfaces...
Categories: Publication; Types: Citation; Tags: Sedimentology
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Deposits within the floor of the Norwegian Basin were sampled to characterize the deposition from the Storegga Slide, the largest known Holocene-aged continental margin slope failure complex. A 29 to 67 cm thick veneer of variable-coloured, finely layered Holocene sediment caps a homogeneous, extremely well-sorted, poorly consolidated, very fine-grained, grey-coloured sediment section that is >20 m thick on the basin floor. This homogeneous unit is interpreted to represent the uppermost deposits generated by a gravity flow associated with the last major Storegga Slide event. Sediments analogous to the inferred source material of the slide deposits were collected from upslope on the Norwegian Margin. Sediments sampled...
Categories: Publication; Types: Citation; Tags: Sedimentology
Channel- and lens-shaped deposits of non-eolian red sandstone are enclosed within the eolian Leche-e Member of the Page Sandstone in south-central Utah. Detailed analysis of lithology and geometry, and regional correlation of the red sandstone deposits suggests that the channel-shaped scours and in-filling deposits were formed by ephemeral stream processes, in contrast to earlier interpretations that suggested a marine estuarine origin. We hypothesize that ephemeral streams transporting volcanic debris flowed toward the north and northeast along the western edge of the Page erg. Local avulsion, possibly caused by eolian damming of an adjacent drainage, led to stream flow into low areas of the Page erg. Entrainment...


map background search result map search result map Evolution of a Holocene delta driven by episodic sediment delivery and coseismic deformation, Puget Sound, Washington, USA The tail of the Storegga Slide: Insights from the geochemistry and sedimentology of the Norwegian Basin deposits Geologic context, age constraints, and sedimentology of a Pleistocene volcaniclastic succession near Mount Spurr volcano, south-central Alaska Model Archive Summary for Suspended Sediment,  Acoustic Sediment Surrogate Model 2.0, USGS gage number 13342500, Clearwater River at Spalding, Idaho 2008 - Present Ecosystem History of South Florida's Estuaries Database Version 5 Mineralogic, grain-size, biologic, and stable isotopic analyses of core TOPGUN-SODA10 2A-K from Big Soda Lake, Nevada, USA Sacramento River Basin future daily streamflow and sediment HSPF outputs Data for Field Evaluation of the Sequoia Scientific LISST-ABS Acoustic Backscatter Sediment Sensor Mineralogic, grain-size, biologic, and stable isotopic analyses of core TOPGUN-SODA10 2A-K from Big Soda Lake, Nevada, USA Model Archive Summary for Suspended Sediment,  Acoustic Sediment Surrogate Model 2.0, USGS gage number 13342500, Clearwater River at Spalding, Idaho Geologic context, age constraints, and sedimentology of a Pleistocene volcaniclastic succession near Mount Spurr volcano, south-central Alaska Evolution of a Holocene delta driven by episodic sediment delivery and coseismic deformation, Puget Sound, Washington, USA 2008 - Present Ecosystem History of South Florida's Estuaries Database Version 5 Sacramento River Basin future daily streamflow and sediment HSPF outputs The tail of the Storegga Slide: Insights from the geochemistry and sedimentology of the Norwegian Basin deposits Data for Field Evaluation of the Sequoia Scientific LISST-ABS Acoustic Backscatter Sediment Sensor