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Site content related to keyword: "Lynch Heights Formation"

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

GM8 Geology of the Milford and Mispillion River Quadrangles, Delaware

Geology of the Milford and Mispillion River Quadrangles, Delaware

This map is the first detailed surficial geologic map in southern Kent and northern Sussex counties. Other maps covering the same or adjacent areas have focused on subsurface geology (Benson and Pickett, 1986), hydrogeology (Talley, 1982), or surficial geology on a regional basis (Jordan, 1964; Owens and Denny, 1979; Ramsey and Schenck, 1990). The purpose of this map is to show the distribution of geologic units found at or near the present land surface. These units are composed of the geologic materials that support agriculture and development, are mined for sand and gravel resources, and are the surface-to-subsurface pathway for water.

Map Scale: 
24,000

DGS Geologic Map No. 8 (Milford-Mispillion River Quadrangles) Dataset

DGS Geologic Map No. 8 (Milford-Mispillion River Quadrangles) Dataset

The scanned raster and vector datasets contains the rock unit polygons for the surficial geology for DGS Geologic Map No. 8 (Milford-Mispillion River Quadrangles). This map is the first detailed surficial geologic map in southern Kent and northern Sussex counties.