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Site content related to keyword: "Sussex County"

Cypress Swamp Formation

Qcs

The upper part of the Cypress Swamp Formation is a multi-colored, thinly bedded to laminated, quartzose fine sand to silty fine sand, with areally discontinuous laminae to thin beds of fine to coarse sand, sandy silt, clayey silt, organic silt, and peat. The lowermost 3 to 6 ft of the unit are commonly composed of thin beds of dark-colored, organic-rich, clayey silt with laminae to thin beds of fine sand and peat. Fine sand to fine sandy silt are present at the base of the unit in boreholes where the lower organic-rich beds are absent. Dark-colored, peaty, organic-rich silt and clayey silt with laminae of fine to medium sand as much as 4.5 ft thick are common within 5 ft of land surface, but may be absent in some locations. Colors are shades of brown, gray, and green where the unit contains visible organic matter, and orange, yellow, and red at shallow depths where the organic-rich beds are absent. Clay-sized minerals are a mixed suite that includes kaolinite, chlorite, illite, and vermiculite.

RI76 Stratigraphy, Correlation, and Depositional Environments of the Middle to Late Pleistocene Interglacial Deposits of Southern Delaware

RI76 Stratigraphy, Correlation, and Depositional Environments of the Middle to Late Pleistocene Interglacial Deposits of Southern Delaware

Rising and highstands of sea level during the middle to late Pleistocene deposited swamp to nearshore sediments along the margins of an ancestral Delaware Bay, Atlantic coastline, and tributaries to an ancestral Chesapeake Bay. These deposits are divided into three lithostratigraphic groups: the Delaware Bay Group, the Assawoman Bay Group (named herein), and the Nanticoke River Group (named herein). The Delaware Bay Group, mapped along the margins of Delaware Bay, is subdivided into the Lynch Heights Formation and the Scotts Corners Formation. The Assawoman Bay Group, recognized inland of Delaware’s Atlantic Coast, is subdivided into the Omar Formation, the Ironshire Formation, and the Sinepuxent Formation. The Nanticoke River Group, found along the margins of the Nanticoke River and its tributaries, is subdivided into the Turtle Branch Formation (named herein) and the Kent Island Formation.

Delaware Bay Group deposits consist of bay-margin coarse sand and gravel that fine upward to silt and silty sand. Beds of organic-rich mud were deposited in tidal marshes. Near the present Atlantic Coast, the Delaware Bay Group includes organic-rich muds and shelly muds deposited in lagoonal environments.

Assawoman Bay Group deposits range from very fine, silty sands to silty clays with shells deposited in back-barrier lagoons, to fine to coarse, well-sorted sands deposited in barriers and spits.

Nanticoke River Group deposits consist of coarse sand and gravel that fine upward to silty clays. Oyster shells are found associated with the clays in the Turtle Branch Formation. Organic-rich clayey silts were deposited in swamps and estuaries. Well-sorted fine sands to gravelly sands were deposited on beaches and tidal flats on the flanks of the ancestral Nanticoke River and its tributaries.

The Lynch Heights, Omar, and Turtle Branch Formations are age-equivalent units associated with highstands of sea level,which occurred at approximately 400,000 and 325,000 yrs B.P. (MIS 11 and 9, respectively). The Scotts Corners, Ironshire, Sinepuxent, and Kent Island Formations are age-equivalent units associated with highstands of sea level, which occurred between 120,000 and 80,000 yrs B.P. (MIS 5e and 5a, respectively).

Number of Pages: 
50

DGS releases new geologic map of Georgetown area

The Delaware Geological Survey (DGS) has published a new geologic map of the Georgetown area in eastern Sussex County entitled Geologic Map of the Georgetown Quadrangle, Delaware. Geologic Map No. 15 presents the results of research by Kelvin W. Ramsey of the DGS.

DGS issues report on the surficial geology of southern Delaware

Report of Investigation 76

The Delaware Geological Survey (DGS) has released a new technical report entitled Stratigraphy, Correlation, and Depositional Environments of the Middle to Late Pleistocene Interglacial Deposits of Southern Delaware.

GM15 Geologic Map of the Georgetown Quadrangle, Delaware

GM15 Geologic Map of the Georgetown Quadrangle, Delaware

The geologic history of the surficial geologic units of the Georgetown Quadrangle is primarily that of deposition of the Beaverdam Formation and its subsequent modification by erosion and deposition of younger stratigraphic units. The age of the Beaverdam Formation is uncertain due to the lack of age-definitive fossils within the unit. Stratigraphic relationships in Delaware indicate that it is no older than late Miocene and no younger than early Pleistocene. Regional correlations based on similarities of depositional style, stratigraphic position, and sediment textures suggest that it is likely late Pliocene in age; correlative with the Bacons Castle Formation of Virginia (Ramsey, 1992, 2010).

Map Scale: 
24,000

Stream Station: Millsboro Pond Outlet at Millsboro

USGS 01484525 MILLSBORO POND OUTLET AT MILLSBORO, DE

Station Type: 
Stream
Period of Record: 
May 1986 to September 1988; March 1991 to Present
Frequency: 
Monthly
Map County: 
Sussex County
Map Location: 
38.594556,-75.291028

Water Conditions Summary Station Map

Map displaying all observing stations monitored by DGS for current and long-term conditions as part of the Water Conditions Summary for Delaware.

Groundwater Station: DGS Well Nc13-03

DGS Well Nc13-03

Station Type: 
Groundwater
Period of Record: 
1970 to present
Frequency: 
Quarterly
Map County: 
Sussex County
Map Location: 
38.825698, -75.615997

Presentation on land application of waste water

Scott Andres of the Delaware Geological Survey presented “Land application of wastewater” and participated in a panel discussion of land use effects on water resources at a forum sponsored by the Sussex County League of Women Voters in Georgetown, Del., Jan 13.
Also, Andres presented “Groundwater Resources and Ag Water Use in Delaware” at the irrigation session during Delaware Ag Week in Harrington, Del., Jan 20.

Meteorological Station: Greenwood

Greenwood Meterological Station

Station Type: 
Meteorological
Period of Record: 
1986 to present
Frequency: 
Monthly
Map County: 
Sussex County
Map Location: 
38.80706,-75.59132

Meteorological Station: City of Lewes

City of Lewes Meteorological Station

Station Type: 
Meteorological
Period of Record: 
1949 to Mar 2011
Frequency: 
Monthly
Map County: 
Sussex County
Map Location: 
38.769555,-75.138527

Hydrogeologic Resources for Delaware

Brandywine Creek in Northern Delaware

Hydrogeologic data and information for Delaware. This includes the Water Conditions Report, groundwater well data, links to real-time data from DEOS and USGS, and other general information about Delaware's hydrogeology.

Groundwater Station: DGS Well Qe44-01

DGS Well Qe44-01

Station Type: 
Groundwater
Period of Record: 
1959 to Present
Frequency: 
Monthly
Map County: 
Sussex County
Map Location: 
38.527698,-75.433502

Groundwater Station: DGS Well Mc51-01a

DGS Well Mc51-01a

Station Type: 
Groundwater
Period of Record: 
1958 to Present
Frequency: 
Monthly
Map County: 
Sussex County
Map Location: 
38.845401,-75.665496

Meteorological Station: Town of Selbyville

Town of Selbyville Meterological Station

Station Type: 
Meteorological
Period of Record: 
1994 to Present
Frequency: 
Monthly
Map County: 
Sussex County
Map Location: 
38.466667,-75.216667

Meteorological Station: Georgetown Sussex County Airport

Georgetown NWS Meterological Station

Station Type: 
Meteorological
Period of Record: 
1949 to Present
Frequency: 
Monthly
Map County: 
Sussex County
Map Location: 
38.683333,-75.366667