Surface-sediment grain-size distributions from the Elwha River delta, Washington, May 2014
Dates
Publication Date
2017
Date Collected
2014-05-12
Citation
Stevens, A.W., Gelfenbaum, G., Warrick, J.A., Miller, I.M., and Weiner, H.M., 2017, Bathymetry, topography, and sediment grain-size data from the Elwha River delta, Washington, April and May 2014: U.S. Geological Survey data release, http://dx.doi.org/10.5066/F76T0JSP
Summary
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 was added to remove [...]
Summary
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 was added to remove organic material in the sample. The sample was heated at 250 °C to remove any remaining hydrogen peroxide and was placed in an ultrasonic bath to liberate the fine fraction. Subsequently the sample was centrifuged for 1.5 hours to remove soluble salts. Samples were funneled through 2 mm and 63 um sieves to separate the gravel (>2 mm), sand (63 um to 2 mm), and mud (<63 um). The sand and gravel fractions were dried in an 80 °C oven and weighed. Five mL of sodium hexametaphosphate was added to the mud fraction and a 20 mL aliquot was taken from a 1 L graduated cylinder to determine the weight of the mud. The particle-size distribution of the mud and sand fractions was analyzed separately using a Beckman Coulter LS 13 320, and the gravel, sand, and mud results were integrated into a single grain-size distribution for each sample. The final grain-size data are provided in comma-separated text format (.csv).
Data were obtained to assess the ecosystem response following the removal of two dams on the Elwha River. These data are intended for science researchers, students, policy makers, and the general public.
