Contours at Base of Onshore Quaternary Sediments for the region of Grand Strand, South Carolina(ONSHORE_CON, Polygon shapefile)

In 1999, the U.S. Geological Survey (USGS), in partnership with the South Carolina Sea Grant Consortium, began a study to investigate processes affecting shoreline change along the northern coast of South Carolina, focusing on the Grand Strand region. Previous work along the U.S. Atlantic coast shows that the structure and composition of older geologic strata located seaward of the coast heavily influences the coastal behavior of areas with limited sediment supply, such as the Grand Strand. By defining this geologic framework and identifying the transport pathways and sinks of sediment, geoscientists are developing conceptual models of the present-day physical processes shaping the South Carolina coast. The primary objectives of this research effort are: 1) to provide a regional synthesis of the shallow geologic framework underlying the coastal upland, shoreface and inner continental shelf, and define its role in coastal evolution and modern beach behavior; 2) to identify and model the physical processes affecting coastal ocean circulation and sediment transport, and to define their role in shaping the modern shoreline; and 3) to identify sediment sources and transport pathways; leading to construction of a regional sediment budget.

1999年，美国地质调查局（U.S. Geological Survey, USGS）与南卡罗来纳州海洋资助联盟（South Carolina Sea Grant Consortium）合作启动一项研究，旨在探究影响南卡罗来纳州北部海岸海岸线变化的各类过程，研究重点聚焦大斯特兰德地区（Grand Strand）。此前美国大西洋沿岸的相关研究显示，海岸向海侧的古老地质地层的结构与组成，会对沉积物供给有限的区域（如大斯特兰德地区）的海岸行为产生显著影响。通过明确该地质框架并识别沉积物的运移路径与汇点，地球科学家正构建塑造南卡罗来纳州海岸的现代物理过程的概念模型。本研究的核心目标如下：1） 对海岸高地、滨面（shoreface）及内大陆架（inner continental shelf）浅部的浅层地质框架开展区域综合研究，并明确其在海岸演化与现代海滩行为中的作用；2） 识别并模拟影响海岸海洋环流与沉积物运移的物理过程，明确其在塑造现代海岸线中的作用；3） 识别沉积物源区与运移路径，进而构建区域沉积物收支。