Surface-sediment grain-size distributions from the Elwha River delta, Washington, August 2012

This portion of the data release presents sediment grain-size data from samples collected on the Elwha River delta, Washington, in August 2012 (USGS Field Activity 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. The locations of grab samples were determined with a hand-held global navigation satellite system (GNSS). The grain-size distributions of samples were determined using standard techniques developed by the USGS Pacific Coastal and Marine Science Center sediment lab. Grab samples that yielded less than 50 g of sediment were omitted from analysis and are classified as "no sample". The grain-size data are provided in a comma-delimited spreadsheet (.csv).本数据集发布的此部分内容包含2012年8月于美国华盛顿州埃尔瓦河三角洲采集的沉积物粒度数据，对应美国地质调查局（USGS）野外活动编号W-05-12-PS。2012年8月28日至8月30日，研究团队依托“前沿号”（R/V Frontier）科考船，在三角洲周边水深约1至9米的区域内，共设置57个采样点位，采用小型波诺采泥器（又称“抓斗式采泥器”）采集表层沉积物样品。所有抓斗采样点位均通过手持全球导航卫星系统（GNSS）确定坐标。样品的粒度分布由美国地质调查局太平洋海岸与海洋科学中心沉积物实验室开发的标准实验方法测定。采集到的沉积物重量不足50克的抓斗样品将被排除在分析之外，并归类为“无样品”。本次粒度数据以逗号分隔值电子表格（.csv）格式提供。