Digital data released by the DGS represent the results of original professional research and are used by professionals and the public.
Lithologic logs from 268 vibracores taken from the Delaware Atlantic offshore were evaluated for sediment type and compatibility with historical beach sediment textures. A model of sand resource evaluation, known as "stack-unit mapping" (Kempton, 1981) was applied to all of the cores, and each core was labeled by its lithology in vertical sequence. The results are shown in detailed maps of the beach-quality sand resources offshore in state and federal waters.
Sand and gravel are essential for supporting and maintaining economic development throughout Delaware. These natural resources are used primarily for aggregate in the productions of concrete for residential, commercial, and industrial buildings, bridge and highway construction, fill for road beds and foundations, water and wastewater treatment facilities, and for replenishment of our Atlantic and Delaware Bay beaches.
The purpose of this report is to provide information on the mining industry of Delaware as an essential component of a growing economy. The industry, particularly in sand and gravel mining, must deal with uneven regulation, land use competition, and environmental pressures. It is hoped that the information gathered here will assist planning and regulatory agencies as well as an interested general public in evaluating the role of the extractive mineral industry.
In Delaware, the oldest unit of the Atlantic Coastal Plain is the Potomac Formation. Sediment eroded from the Appalachian Mountains was deposited in rivers and swamps in a tropical climate along the margins of the forming ocean during the latter part of Early Cretaceous time, about 120 million years ago.