1997 shotpoint navigation at 500 shot intervals off the coast of Washington and Oregon (geographic coordinates)

Two 21-day field operations were conducted in 1997 and 1998 in the estuaries and on the inner continental shelf off the northern Oregon and southern Washington coast. These cruises aboard the R/V Corliss were run in order to generate reconnaissance maps of the seafloor geology and the shallow subsurface stratigraphy using sidescan sonar and seismic-reflection mapping techniques. The 1998 cruise also collected sediment grab samples, bottom photographs, and video images to verify the sidescan-sonar imagery and to document the seafloor geology. The combination of these data with previously collected sediment sample data (Robert, 1974; Nittrouer, 1978; and Smith et. al., 1980) has been used to define the extent and lithology of shelf sediments associated with the Columbia River littoral cell. This work is one component of a larger project studying the erosion of the Washington and Oregon coast and is being coordinated by the U.S. Geological Survey and the Washington State Department of Ecology. The reason for collecting these data is to provide a regional synthesis of the offshore geology to support a wide variety of management decisions and to provide a basis for further process-oriented investigations.1997年与1998年，研究团队于俄勒冈州北部及华盛顿州南部沿岸的河口区域与内陆架海域，先后开展两期为期21天的野外调查作业。本次科考由R/V Corliss号考察船执行，旨在通过侧扫声呐与地震反射测绘技术，绘制海底地质与浅地下地层结构的普查图件。1998年的航次额外采集了沉积物抓取样品、海底摄影照片及视频影像，用于验证侧扫声呐成像结果并详实记录海底地质特征。本研究将本次采集的数据与此前已收集的沉积物样品数据（Robert，1974；Nittrouer，1978；Smith等，1980）进行整合，以此明确与哥伦比亚河沿岸输沙单元相关的陆架沉积物的分布范围与岩性特征。此项工作是华盛顿州与俄勒冈州海岸侵蚀大型研究项目的组成部分，由美国地质调查局（U.S. Geological Survey）与华盛顿州生态部统筹协调。本次数据采集的核心目标为构建近海地质的区域综合数据集，为各类海洋管理决策提供支撑，并为后续面向过程的专项研究奠定基础。