USGS_Delmarva_SedTexture_Geomorph: Sediment Texture and Geomorphology of the Sea Floor from Fenwick Island, Maryland to Fisherman's Island, Virginia (polygon shapefile, Geographic, WGS84)

These data are a qualitatively derived interpretive polygon shapefile defining surficial sediment type and distribution, and geomorphology, for nearly 1,400 square kilometers of sea floor on the inner-continental shelf from Fenwick Island, Maryland to Fishermans Island, Virginia, USA. These data are classified according to Barnhardt and others (1998) bottom-type classification system, which was modified to highlight changes in secondary sediment-types such as mud and gravel across this primarily sandy shelf. Most of the geophysical and sample data used to create this interpretive layer were collected as part of the Linking Coastal Processes and Vulnerability: Assateague Island Regional Study project (GS2-2C), supported by the U.S. Department of the Interior Hurricane Sandy Recovery program. Additional sample data were provided by the Maryland Geological Survey and the Virginia Division of Geology and Mineral Resources. Additional hydrographic data were available through the National Oceanographic and Atmospheric Administrations National Ocean Service surveys collected between 2006 and 2014. The primary objective of the Hurricane Sandy Recovery program is to provide science for coastal resilience, and these interpretive data support the program goal by supplying regional geologic framework information for the management of coastal and marine resources. Accurate data and maps of seafloor geology are important first steps toward protecting fish habitat, delineating marine resources on the inner-shelf, understanding sediment transport pathways, and assessing environmental changes because of natural or human effects. The Assateague Island Regional Study project is focused on the inner-continental shelf of Maryland and Virginia, north of Chesapeake Bay entrance. Data collected during the mapping portion of this study have been released in a series of USGS data releases (https://woodshole.er.usgs.gov/project-pages/delmarva/). A combination of geophysical and sample data including high resolution bathymetry, acoustic-backscatter intensity, bottom photographs, and sediment samples are used to create this seafloor interpretation.

本数据集为经定性推导得到的解释性多边形矢量shapefile（shapefile），用于界定美国马里兰州芬威克岛至弗吉尼亚州费希尔曼岛附近近1400平方千米陆架浅海区域的海底表层沉积物类型与分布及地貌形态。本数据集依据Barnhardt等人（1998）提出的底质分类系统开展分类，该系统经修改后可突出本以砂质为主的陆架区域内泥、砾石等次级沉积物类型的分布变化。用于生成该解释图层的大部分地球物理与采样数据，均取自“关联海岸过程与脆弱性：阿萨蒂格岛区域研究”（Linking Coastal Processes and Vulnerability: Assateague Island Regional Study）项目（编号GS2-2C），该项目由美国内政部桑迪飓风恢复计划资助。额外采样数据由马里兰州地质调查局与弗吉尼亚州地质与矿产资源局提供。补充水文数据则取自2006至2014年间由美国国家海洋和大气管理局（National Oceanic and Atmospheric Administration, NOAA）国家海洋服务局开展的勘测项目。桑迪飓风恢复计划的核心目标是为海岸韧性建设提供科学支撑，本解释数据集通过提供区域地质框架信息以辅助海岸与海洋资源管理，契合该计划的目标。精准的海底地质数据与图件是开展多项核心工作的首要基础：包括保护鱼类栖息地、划定陆架浅海海洋资源范围、明晰沉积物输运路径，以及评估自然或人为活动引发的环境变化。阿萨蒂格岛区域研究项目的研究区域为切萨皮克湾入口以北的马里兰州与弗吉尼亚州陆架浅海区。本研究制图阶段采集的数据已以一系列美国地质调查局（United States Geological Survey, USGS）数据发布形式公开，公开链接为：https://woodshole.er.usgs.gov/project-pages/delmarva/。本海底地质解释图层的生成综合运用了多类地球物理与采样数据，包括高分辨率水深测量数据、声学背散射强度数据、海底照片以及沉积物样品。