The geologic history of the surficial units of the Bethany Beach and Assawoman Bay Quadrangles is that of deposition of the Beaverdam Formation and its subsequent modification by erosion and deposition related to sea-level fluctuations during the Pleistocene. The geology reflects this complex history onshore, in Indian River Bay and Assawoman Bay, and offshore in the Atlantic Ocean.
This report supplements the map "Geology of the Seaford Area, Delaware" (Andres and Ramsey, 1995). The map portrays surficial and shallow subsurface stratigraphy and geology in and around the Seaford East and Delaware portion of the Seaford West quadrangles. The Quaternary Nanticoke deposits and Pliocene Beaverdam Formation are the primary lithostratigraphic units covering upland surfaces in the map area. Recent swamp, alluvial, and marsh deposits cover most of the floodplains of modern streams and creeks. The Miocene Choptank, St.
Southern New Castle County is dependent on ground water for nearly all of its water supply. The area has been undergoing development from predominately agricultural land use to urban/suburban land use (Delaware Water Supply Coordinating Council [WSCC], 2006). With this development comes a need to more accurately predict the availability of ground water to reduce the potential of overusing the resource. This report has 3 plates listed as separate files.
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.
The ground-water recharge potential map of Kent County, Delaware, is a compilation of 1:24,000-scale maps of the water-transmitting properties of sediments in the interval between land surface and 20 ft below land surface. Water-transmitting properties are a key factor in determining the amount of water that recharges Delawareâs aquifers and the susceptibility of aquifers used as sources of water supply to contamination from near-surface pollutant sources.
Geology and hydrology of the Smyrna-Clayton area, Delaware. There are 2 sheets in this series.
Geology and hydrology of the Southern Coastal Area, Delaware. There are 2 sheets in this series.
This map shows the surficial geology of Kent County, Delaware at a scale of 1:100,000. Maps at this scale are useful for viewing the general geologic framework on a county-wide basis, determining the geology of watersheds, and recognizing the relationship of geology to regional or county-wide environmental or land-use issues. This map, when combined with the subsurface geologic information, provides a basis for locating water supplies, mapping ground-water recharge areas, and protecting ground and surface water.