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This portion of the USGS data release presents digital elevation models (DEMs) derived from bathymetric and topographic surveys conducted on the Elwha River delta, Washington, in September 2013 (USGS Field Activity Number W-07-13-PS). Nearshore bathymetry data were collected using two personal watercraft (PWCs) equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers. Topography data were collected on foot with survey-grade GNSS receivers mounted on backpacks. Positions of the survey platforms were referenced to a GNSS base station placed on a benchmark with known horizontal and vertical coordinates relative to the North American Datum of 1983 (CORS96 realization)...
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This portion of the USGS data release presents sediment grain-size data from samples collected on the Elwha River delta, Washington, in August 2012 (USGS Field Activity Number W-05-12-PS). Surface sediment was sampled using a small ponar, or 'grab', sampler between August 28 and August 30, 2012 from the R/V Frontier at a total of 57 locations in water depths between about 1 and 9 m around the delta. A handheld global satellite navigation system (GNSS) receiver was used to determine the locations of sediment samples. Grab samples that yielded less than 50 g of sediment were omitted from analysis and are classified as "no sample". The grain-size distributions of samples that yielded more than 50 g of sediment were...
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This portion of the USGS data release presents digital elevation models (DEMs) derived from bathymetric and topographic surveys conducted on the Elwha River delta, Washington, in September 2014 (USGS Field Activity Number 2014-649-FA). Nearshore bathymetry data were collected using two personal watercraft (PWCs) equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers. Topography data were collected on foot with survey-grade GNSS receivers mounted on backpacks. Positions of the survey platforms were referenced to a GNSS base station placed on a benchmark with known horizontal and vertical coordinates relative to the North American Datum of 1983 (CORS96 realization)...
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This portion of the USGS data release presents bathymetry data collected during surveys performed on the Elwha River delta, Washington in April 2014 (USGS Field Activity Number 2014-620-FA). Bathymetry data were collected using two personal watercraft (PWCs), each equipped with single-beam sonar systems and global navigation satellite system (GNSS) receivers. The PWC sonar systems consisted of an Odom Echotrac CV-100 single-beam echosounder and 200 kHz transducer with a 9° beam angle. Raw acoustic backscatter returns were digitized by the echosounder with a vertical resolution of 1.25 cm. Depths from the echosounders were computed using sound velocity profiles measured using a YSI CastAway CTD during the survey....
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This portion of the USGS data release presents sediment grain-size data from samples collected on the Elwha River delta, Washington, in March 2013 (USGS Field Activity Number W-01-13-PS). Surface sediment was sampled using a small ponar, or 'grab', sampler on March 4, 2013 from the R/V Frontier at a total of 48 locations in water depths between about 1 and 12 m around the delta. An additional 7 sediment samples were collected between March 6 and March 7, 2013 at low tide from intertidal locations on the delta. A handheld global satellite navigation system (GNSS) receiver was used to determine the locations of sediment samples. Grab samples that yielded less than 50 g of sediment were omitted from analysis and are...
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Two dams on the Elwha River, Washington State, USA trapped over 20 million m3 of sediment, reducing downstream sediment fluxes and contributing to erosion of the river's coastal delta. The removal of the Elwha and Glines Canyon dams between 2011 and 2014 induced massive increases in river sediment supply and provided an unprecedented opportunity to examine the response of a delta system to changes in sediment supply. The U.S. Geological Survey (USGS) developed an integrated research program aimed at understanding the ecosystem responses following dam removal. The research program included repeated surveys of beach topography, nearshore bathymetry, and surface sediment grain size to quantify changes in delta morphology...
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This portion of the USGS data release presents bathymetry data collected during surveys performed in the Columbia River littoral cell, Washington and Oregon in 2018 (USGS Field Activity Number 2018-652-FA). Bathymetry data were collected using four personal watercraft (PWCs) equipped with single-beam sonar systems and global navigation satellite system (GNSS) receivers. The sonar systems consisted of an Odom Echotrac CV-100 single-beam echosounder and 200 kHz transducer with a 9 degree beam angle. Raw acoustic backscatter returns were digitized by the echosounder with a vertical resolution of 1.25 cm. Depths from the echosounders were computed using sound velocity profiles measured using a YSI CastAway CTD during...
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This portion of the USGS data release presents digital elevation models (DEMs) derived from bathymetric and topographic surveys conducted along northern Monterey Bay, California, in March 2016 (USGS Field Activity Number 2016-627-FA). Nearshore bathymetry data were collected using two personal watercraft (PWCs) equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers. Topography data were collected using an all-terrain vehicle equipped with a GNSS receiver and on foot with GNSS receivers mounted on backpacks. Additional topography data were collected with a terrestrial lidar scanner. Positions of the survey platforms were referenced to a GNSS base station placed...
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This portion of the USGS data release presents sediment grain-size data from samples collected on the Elwha River delta, Washington, in May 2014 (USGS Field Activity Number 2014-620-FA). Surface sediment was collected on May 12, 2014, at a total of 43 locations using a small ponar, or 'grab', sampler from a small boat in water depths between approximately 1 and 12 m around the delta. A hand-held global satellite navigation system (GNSS) receiver was used to determine the locations of sediment samples. The grain-size distributions of samples were determined in the USGS Pacific Coastal and Marine Science Center sediment lab. Approximately 20 g of sediment was sub-sampled and 10 mL of 35 percent hydrogen peroxide...
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This portion of the USGS data release presents topography data collected during surveys performed on the Elwha River delta, Washington, in July 2015 (USGS Field Activity Number 2015-648-FA). Topography data were collected on foot with global navigation satellite systems (GNSS) equipment mounted on backpacks operating primarily in Real-Time Kinematic (RTK) mode. A total of 5 GNSS backpacks, each equipped with a dual-frequency GNSS receiver and handheld data collector, were used during the survey. Differential corrections were transmitted at 1-Hz intervals by a VHF radio to the backpack GNSS receivers from a GNSS base station placed on a benchmark with known horizontal and vertical coordinates relative to the North...


map background search result map search result map Topography data from the Elwha River delta, Washington, July 2015 Digital elevation models (DEMs) of the Elwha River delta, Washington, September 2014 Nearshore bathymetry data from the Elwha River delta, Washington, April 2014 Surface-sediment grain-size distributions from the Elwha River delta, Washington, May 2014 Digital elevation models (DEMs) of the Elwha River delta, Washington, September 2013 Surface-sediment grain-size distributions from the Elwha River delta, Washington, March 2013 Surface-sediment grain-size distributions from the Elwha River delta, Washington, August 2012 Digital elevation models (DEMs) of northern Monterey Bay, California, March 2016 Bathymetry, topography, and sediment grain-size data from the Elwha River delta, Washington Nearshore bathymetry of the Columbia River littoral cell, Washington and Oregon, 2018 Digital elevation models (DEMs) of the Elwha River delta, Washington, September 2013 Digital elevation models (DEMs) of the Elwha River delta, Washington, September 2014 Topography data from the Elwha River delta, Washington, July 2015 Nearshore bathymetry data from the Elwha River delta, Washington, April 2014 Bathymetry, topography, and sediment grain-size data from the Elwha River delta, Washington Digital elevation models (DEMs) of northern Monterey Bay, California, March 2016 Nearshore bathymetry of the Columbia River littoral cell, Washington and Oregon, 2018