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Site content related to keyword: "Beaverdam Formation"

RI47 Ages of the Bethany, Beaverdam, and Omar Formations of Southern Delaware

RI47 Ages of the Bethany, Beaverdam, and Omar Formations of Southern Delaware

The microflora of the Bethany formation and the lower part of the Beaverdam Formation is characterized by a Quercus-Carya assemblage, very few non-arboreal pollen, and Pterocarya and Sciadopitys as exotic constituents. This assemblage has much in common with that of the Brandywine Formation of Maryland and the Eastover Formation of Virginia which are of late Miocene or early Pliocene age. The environment of deposition of the Bethany was probably deltaic, and that of the lower Beaverdam fluviatile.

RI24 Relation of Ground Water to Surface Water in Four Small Basins of the Delaware Coastal Plain

RI24 Relation of Ground Water to Surface Water in Four Small Basins of the Delaware Coastal Plain

Beaverdam Branch, the Nanticoke River, Sowbridge Branch, and Stockley Branch drain small basins in the Delaware Coastal Plain that are characterized by similar climate, topography, geology, and land use. Withdrawals of ground water and surface water are very small, there is little urbanization, and other man-made effects, which include minor regulation on Sowbridge Branch and construction of drainage ditches in the Nanticoke basin, probably have had minimal effect on the natural hydrologic regimen. These are virtually natural-flow streams, which, because of similar basin characteristics, have nearly identical rates of evapotranspiration and runoff. During the 10-year period, 1959-68, precipitation averaged 40-42 inches annually, runoff averaged 16-17 inches annually, and evapotranspiration averaged 23-25 inches annually.

Coastal Plain Rock Units (Stratigraphic Chart)

The geology of Delaware includes parts of two geologic provinces: the Appalachian Piedmont Province and the Atlantic Coastal Plain Province. The Piedmont occurs in the hilly northernmost part of the state and is composed of crystalline metamorphic and igneous rocks. This chart summarizes the age and distribution of the geologic units that are recognized in the state by the Delaware Geological Survey.

GM14 Geologic Map of Kent County, Delaware

GM14 Geologic Map of Kent County, Delaware

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. Geologic maps are also used to identify geologic hazards, such as flood-prone areas, to identify sand and gravel resources, and to support state, county, and local land-use and planning decisions.

Map Scale: 
100,000

GM12 Geology of the Lewes and Cape Henlopen Quadrangles, Delaware

GM12 Geology of the Lewes and Cape Henlopen Quadrangles, Delaware

The surficial geology of the Lewes and Cape Henlopen quadrangles reflects the geologic history of the Delaware Bay estuary and successive high and low stands of sea levels during the Quaternary. The subsurface Beaverdam Formation was deposited as part of a fluvial-estuarine system during the Pliocene, the sediments of which now form the core of the Delmarva Peninsula. Following a period of glacial outwash during the early Pleistocene represented by the Columbia Formation found to the northwest of the map area (Ramsey, 1997), the Delaware River and Estuary developed their current positions. The Lynch Heights and Scotts Corners Formations (Ramsey, 1993, 1997, 2001) represent shoreline and estuarine deposits associated with high stands of sea level during the middle to late Pleistocene on the margins of the Delaware Estuary. In the map area, the Lynch Heights Formation includes relict spit and dune deposits at the ancestral intersection of the Atlantic Coast and Delaware Bay systems, similar in geomorphic position to the modern Cape Henlopen.

Map Scale: 
24,000

GM11 Geology of the Ellendale and Milton Quadrangles, Delaware

GM11 Geology of the Ellendale and Milton Quadrangles, Delaware

The surficial geology of the Ellendale and Milton quadrangles reflects the geologic history of the Delaware Bay estuary and successive high and low sea levels during the Quaternary. Ramsey (1992) interpreted the Beaverdam Formation as deposits of a fluvial-estuarine system during the Pliocene. Sediment supply was high, in part due to geomorphic adjustments in the Appalachians related to the first major Northern Hemisphere glaciations around 2.4 million years ago. The Beaverdam Formation forms the core of the central Delmarva Peninsula around which wrap the Quaternary deposits.

Map Scale: 
24,000

GM9 Geology of the Seaford Area, Delaware

GM9 Geology of the Seaford Area, Delaware

This map shows the distribution of geologic units found at or near land surface. These units support agriculture and development, are mined for sand and gravel resources, and are the surface-to-subsurface pathway for water. Previous maps and reports covering the same of adjacent areas have focused on hydrogeology (Andres, 1994), surficial geology on a regional basis (Jordan, 1964, 1974; Owens and Denny, 1979, 1986; Denny et al., 1979; Ramsey and Schenck, 199), or subsurface geology (Hansen, 1981; Andres, 1986).

Map Scale: 
24,000

DGS Geologic Map No. 9 (Seaford area) Dataset

DGS Geologic Map No. 9 (Seaford area) Dataset

These raster and vector datasets contains the rock unit polygons for DGS Geologic Map No. 9 (Seaford). This map shows the distribution of geologic units found at or near land surface.

DGS issues report on the geology of Bethany Beach

RI75 Stratigraphy And Correlation Of The Oligocene To Pleistocene Section At Bethany Beach, Delaware

The Delaware Geological Survey (DGS) at the University of Delaware released a report that provides new insights into the underground geology and hydrology of southeastern Sussex County, Delaware. The report, "Stratigraphy and Correlation of the Oligocene to Pleistocene Section at Bethany Beach, Delaware," summarizes the results of geological investigations conducted on a 1,470-foot-deep research borehole drilled at Bethany Beach, Del.