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Site content related to keyword: "sand resources"

DGS Geologic Map No. 16 (Fairmont Rehoboth Beach Quadrangles) Dataset

DGS Geologic Map No. 16 (Fairmont Rehoboth Beach Quadrangles) Dataset

This vector data set contains the rock unit polygons for the surficial geology in the Delaware Coastal Plain covered by DGS Geologic Map No. 16 (Fairmount and Rehoboth Beach quadrangles). The geologic history of the surficial units of the Fairmount and Rehoboth Beach 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 both onshore, in Rehoboth Bay, and offshore. Erosion during the late Pleistocene sea-level low stand and ongoing deposition offshore and in Rehoboth Bay during the Holocene rise in sea level represent the last of several cycles of erosion and deposition.

To facilitate the GIS community of Delaware and to release the geologic map of the Fairmount and Rehoboth Beach quadrangles with all cartographic elements (including geologic symbology, text, etc.) in a form usable in a GIS, we have released this digital coverage of DGS Geological Map 16. The update of earlier work and mapping of new units is important not only to geologists, but also to hydrologists who wish to understand the distribution of water resources, to engineers who need bedrock information during construction of roads and buildings, to government officials and agencies who are planning for residential and commercial growth, and to citizens who are curious about the bedrock under their homes. Formal names are assigned to all rock units according to the guidelines of the 1983 North American Stratigraphic Code (NACSN, 1983).

DGS releases new geologic map of Rehoboth Beach area

The Delaware Geological Survey (DGS) has published a new geologic map of the Rehoboth Beach area in eastern Sussex County entitled Geologic Map of the Fairmount and Rehoboth Beach Quadrangles, Delaware. Geologic Map 16 presents the results of research by Kelvin W. Ramsey of the DGS.

GM16 Geologic Map of the Fairmount and Rehoboth Beach Quadrangles, Delaware

GM16 Geologic Map of the Fairmount and Rehoboth Beach Quadrangles, Delaware

The geologic history of the surficial units of the Fairmount and Rehoboth Beach 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 both onshore, in Rehoboth Bay, and offshore. Erosion during the late Pleistocene sea-level low stand and ongoing deposition offshore and in Rehoboth Bay during the Holocene rise in sea level represent the last of several cycles of erosion and deposition.

Map Scale: 
24,000

Delaware Offshore Geologic Inventory Dataset

Delaware Offshore Geologic Inventory Dataset

Since 1992, the Delaware Geological Survey (DGS) has compiled a geologic database known as the Delaware Offshore Geologic Inventory (DOGI) that consists of sediment samples, radiocarbon and amino acid racemization dates, seismic profiles, and vibracores taken from the near-shore and inner continental shelf in state and federal waters. Most of the 366 vibracores are stored at the DGS on-site core and sample repository.

Delaware Offshore Geologic Inventory Map

Since 1992, the Delaware Geological Survey (DGS) has compiled a geologic database known as the Delaware Offshore Geologic Inventory (DOGI) that consists of sediment samples, radiocarbon and amino acid racemization dates, seismic profiles, and vibracores taken from the nearshore and inner continental shelf in state and federal waters. Most of the 366 vibracores are stored at the DGS on-site core and sample repository.

DGS Digital Datasets

In the same ways as our printed publications, digital data released by the DGS represent the results of original professional research and as such are used by professionals and the public.

RI63 An Evaluation of Sand Resources, Atlantic Offshore, Delaware

RI63 An Evaluation of Sand Resources, Atlantic Offshore, Delaware

Lithologic logs from 268 vibracores taken from the Delaware Atlantic offshore were evaluated for sediment type and compatibility with historical beach sediment textures. A model of sand resource evaluation, known as "stack-unit mapping" (Kempton, 1981) was applied to all of the cores, and each core was labeled by its lithology in vertical sequence. The results are shown in detailed maps of the beach-quality sand resources offshore in state and federal waters. Results show significant quantities (approximately 54 million cubic yards) of excellent beach-quality sand sources within the three-mile state limit offshore Indian River Inlet, and within the Inner Platform and Detached Shoal Field geomorphic regions. In federal waters, sand is found on Fenwick Shoal Field and farther offshore Indian River Inlet on the Outer Platform (approximately 43.6 million cubic yards combined). Most of the beach-quality sand resources are believed to be reworked tidal delta deposits of a former Indian River Inlet during periods of lower sea level. Farther south, the resources are accumulations of recent surficial sands of the inner shelf (Detached Shoal Field and Fenwick Shoal Field) showing that the geomorphic region does influence sediment quality. This study found that paleochannels and bathymetry had no relationship to grain size. Multiple cut and fill episodes contributed to the diversity in grain sizes.

Sand and Gravel

Locations of Sand and Gravel Producers in Delaware

Sand and gravel are essential for supporting and maintaining economic development throughout Delaware. These natural resources are used primarily for aggregate in the productions of concrete for residential, commercial, and industrial buildings, bridge and highway construction, fill for road beds and foundations, water and wastewater treatment facilities, and for replenishment of our Atlantic and Delaware Bay beaches.

OFR13 Delaware's Extractive Mineral Industry

OFR13 Delaware's Extractive Mineral Industry

The purpose of this report is to provide information on the mining industry of Delaware as an essential component of a growing economy. The industry, particularly in sand and gravel mining, must deal with uneven regulation, land use competition, and environmental pressures. It is hoped that the information gathered here will assist planning and regulatory agencies as well as an interested general public in evaluating the role of the extractive mineral industry.

Geologic History of the Delaware Coastal Plain

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.