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Site content related to keyword: "Fenwick Island"

From where should beach replenishment sand come?

Delaware, Maryland and Virginia have received funds from the federal Disaster Relief Appropriations Act of 2013 to compile data on sand deposits. The data will give clues to where sand is located for future beach replenishment projects. (Photo: FILE PHOTO )

Delaware, Maryland and Virginia have each partnered with the Bureau of Ocean Energy Management to find new sand sources using existing mapping data. As part of the federal Disaster Relief Appropriations Act of 2013, which allocated $13.6 million to the bureau, all three states will each receive $200,000 for the two-year project.

DGS releases new geologic map of Bethany Beach and Fenwick Island area

The Delaware Geological Survey (DGS) has published a new geologic map of the Bethany Beach and Fenwick Island area in eastern Sussex County titled Geologic Map of the Bethany Beach and Assawoman Bay Quadrangles, Delaware.

Geologic Map 18 presents the results of research by Kelvin W. Ramsey and Jaime Tomlinson of the DGS and is the first web-only map published by the DGS.

DGS Geologic Map No. 18 (Bethany Beach and Assawoman Bay Quadrangles, Delaware) Dataset

DGS Geologic Map No. 18 (Bethany Beach and Assawoman Bay Quadrangles, Delaware) Dataset

This vector data set contains the rock unit polygons for the surficial geology in the Delaware Coastal Plain covered by DGS Geologic Map Series No. 18 (Bethany Beach and Assawoman Bay Quadrangles). 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. Erosion during the late Pleistocene sea-level lowstand and ongoing deposition offshore and in Indian River Bay during the Holocene rise in sea level represents the latest of several cycles of erosion and deposition. An additional dataset of datapoints used to generate rock unit polygons for the surficial geology in the Delaware Coastal Plain covered by DGS Geologic Map Series No. 18 (Bethany Beach and Assawoman Bay quadrangles) exists for use in conjunction with this dataset.

GM18 Geologic Map of the Bethany Beach and Assawoman Bay Quadrangles, Delaware

Geologic Map of the Bethany Beach and Assawoman Bay Quadrangles, Delaware

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. Erosion during the late Pleistocene sea-level lowstand and ongoing deposition offshore and in Indian River Bay during the Holocene rise in sea level represents the latest of several cycles of erosion and deposition.

Stream and Tide Gage Data for Hurricane Sandy

GOES Satellite Image of Hurricane Sandy (Image provided by NASA)

Hurricane Sandy was a major storm event for the tidal areas of Delaware. As a part of the mission of the Delaware Geological Survey, we have compiled preliminary data related to Delaware tide and stream levels related to the Hurricane Sandy and compared them with previous flooding records.

The Storm of '62

Kelvin Ramsey was quoted in the special section of Coastal Point, which featured the 50th anniversary of the Ash Wednesday 1962 nor'easter

MS6 Cross Section of Pliocene and Quaternary Deposits Along the Atlantic Coast of Delaware

Cross Section of Pliocene and Quaternary Deposits Along the Atlantic Coast of Delaware

Exploration for sand resources for beach nourishment has led to an increase in the amount of geologic data available from areas offshore Delaware's Atlantic Coast. These data are in the form of cores, core logs, and seismic reflection profiles. In order to provide a geologic context for these offshore data, this cross section has been constructed from well and borehole data along Delaware's Atlantic coastline from Cape Henlopen to Fenwick Island. Placing the offshore data in geologic context is important for developing stratigraphic and geographic models for predicting the location of stratigraphic units found offshore that may yield sand suitable for beach nourishment. The units recognized onshore likely extend offshore to where they are truncated by younger units or by the present seafloor.

RI13 The Occurrence of Saline Ground Water in Delaware Aquifers

RI13 The Occurrence of Saline Ground Water in Delaware Aquifers

The location of the fresh-salt-water-boundary in the deeper aquifers of Delaware is related mainly to head values. Near coastal areas, dynamic conditions may prevail that affect the interface position within shallow aquifers open to the sea. Holocene and Columbia sands which form Delaware's shallow water-table aquifers contain brackish water in scattered coastal areas while brackish water in the artesian aquifers is found at various depths. Water from Chesapeake Group sediments (Miocene) is fresh in Kent County but is salty in poorly defined areas of Sussex County. The interface in the Piney Point Formation (Eocene) lies just north of Milford and extends in a northeast-southwesterly direction across the State. Brackish water exists in the Magothy and Potomac formations of Cretaceous age a few miles south of Middletown. Heavy pumping near sources of brackish water should be avoided for the present. Proper location of monitoring wells is necessary for detection of future chloride movement.