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Site content related to keyword: "Sussex County"

Delaware Geological Survey releases new geologic map of the Trap Pond area

The Delaware Geological Survey (DGS) has published a new geologic map of the Trap Pond and Pittsville areas in central Sussex County titled Geologic Map of the Trap Pond and Pittsville Quadrangles, Delaware.

DGS Geologic Map No. 21 (Trap Pond and Pittsville Quadrangles, Delaware) Dataset

DGS Geologic Map No. 21 (Trap Pond and Pittsville 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. 21 (Trap Pond and Pittsville Quadrangles, Delaware). The geological history of the surficial units of the Trap Pond and the Delaware portion of the Pittsville Quadrangle was the result of deposition of the Beaverdam Formation and its subsequent modification by erosion and deposition related to the sea-level fluctuations during the Pleistocene. The geology reflects this complex history by the cut and fill geometry of the Middle and late Pleistocene deposits into the Beaverdam Formation. The geology is further complicated by periglacial activity that produced dune deposits and Carolina Bays in the map area, which modified the land surface. Surficial geologic mapping was conducted using field maps at a scale of 1:12,000 with 2-foot contours. Stratigraphic boundaries drawn at topographic breaks reflect detailed mapping using contours not shown on this map.

GM21 Geologic Map of the Trap Pond and Pittsville Quadrangles, Delaware

GM21 Geologic Map of the Trap Pond and Pittsville Quadrangles, Delaware

The geological history of the surficial units of the Trap Pond and the Delaware portion of the Pittsville Quadrangle was the result of deposition of the Beaverdam Formation and its subsequent modification by erosion and deposition related to the sea-level fluctuations during the Pleistocene. The geology reflects this complex history by the cut and fill geometry of the Middle and late Pleistocene deposits into the Beaverdam Formation. The geology is further complicated by periglacial activity that produced dune deposits and Carolina Bays in the map area, which modified the land surface. Surficial geologic mapping was conducted using field maps at a scale of 1:12,000 with 2-foot contours. Stratigraphic boundaries drawn at topographic breaks reflect detailed mapping using contours not shown on this map.

Number of Pages: 
1
Map Scale: 
24,000

Delaware Geological Survey releases geologic map of Frankford, Selbyville area

The Delaware Geological Survey (DGS) has published a new geologic map of the Frankford and Selbyville area in eastern Sussex County titled Geologic Map of the Frankford and Selbyville Quadrangles, Delaware.

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Elevation Contours Dataset for Delaware

Elevation Contours Dataset for Delaware

Elevation contours at 2 foot intervals for the State of Delaware were produced for New Castle and Kent Counties based on the 2007 LIDAR) and for Sussex County (based on the 2005 LIDAR.) Data are in line shapefile format.

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.

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.

Number of Pages: 
1
Map Scale: 
24,000

Data and Graphs of Water Level Summaries for Wells with 20+ Years or 100+ Observations

Example Hydrograph for DB24-18 - Water Level Summaries for Wells with 20+ Years or 100+ Observations

Ground-water levels are basic information needed for evaluating water conditions and for basic and applied research. For these efforts, water levels are being measured statewide in wells completed in multiple aquifers. Some wells are measured for specific projects, such as the Coastal Aquifers Salinity Project and the Water Conditions program, while other wells are measured so that staff can maintain long term records of ground-water levels for evaluation of trends. Table contains summary data from wells having 100 or more water level observations.

Effect of tropical storms Irene and Lee on groundwater levels in well Qb35-08 near Laurel, Delaware

Rapid, significant groundwater recharge occurred in response to tropical storms Irene and Lee.a

Effect of tropical storms Irene and Lee on groundwater levels in well Qb35-08

Plot of groundwater levels, groundwater temperature, and rainfall near Laurel, Delaware

Tropical storms Irene and Lee caused a 9-1/2 foot rise of the water table in western Sussex County near Laurel. Groundwater levels and temperatures in Qb35-08 were collected with an automated pressure-temperature datalogger system. At the same time, rainfall and soil moisture data were recorded by the DEOS Laurel Airport station located approximately 5 miles from the well.

Mapping Tsunami Inundation for the U.S. East Coast

National Tsunami Hazard Mitigation Program
Project Contact(s):

This project will assess tsunami hazard from the above mentioned and other relevant tsunami sources recently studied in the literature and model the corresponding tsunami inundation in affected US East coast communities. We will combine ocean scale simulations of transoceanic tsunami sources, such as Lisbon 1755 like or Puerto Rico Trench co-seismic events, and CVV collapse, with regional scale simulations of these events, along with the regional scale SMF events, in order to establish the relative degree of hazards for East Coast communities. Detailed inundation studies will be conducted for highest-risk East Coast communities, and results of these studies will be used to construct a first-generation of tsunami inundation maps for the chosen communities.

DGS Geologic Map No. 17 (Harbeson quadrangle) Dataset

DGS Geologic Map No. 17  (Harbeson quadrangle) 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. 17 (Harbeson quadrangle). The complex geologic history of the surficial units of the Harbeson Quadrangle 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 is further complicated by periglacial activity that produced dune deposits and Carolina Bays scattered throughout the map area.

GM17 Geologic Map of the Harbeson Quadrangle, Delaware

GM17 Geologic Map of the Harbeson Quadrangle, Delaware

The complex geologic history of the surficial units of the Harbeson Quadrangle is one of deposition of the Beaverdam Formation and its subsequent modification by erosion and deposition related to sea-level fluctuations during the Pleistocene. The geology is further complicated by periglacial activity that produced dune deposits and Carolina Bays scattered throughout the map area.

Map Scale: 
24.000

A.Scott Andres was referenced in a News Journal article about Cypress Swamp

In 2000, A. Scott Andres, a senior scientist and hydrologist with the Delaware Geological Survey, released findings that disclosed a unique formation at the swamp.
In geologic time, the swamp isn't that old.
It formed about 22,000 years ago in a fresh-water, cold-climate marsh and boreal forested swamp.
Organic matter started building up and a cold wind blew in silt, clay and sand from nearby dunes and surrounding high ground. More sediment washed in with runoff from streams.
Thin sheets of sand likely spread during times when the land thawed.
Conditions began to change about 10,000 years ago as the climate warmed, forming a temperate-forested swamp, bog and flood plain.
There was more erosion and movement of organic-rich sediment to the fresh-water swamp. Today, it's considered the northernmost Southern forest on the East Coast.

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).

The Delaware Water Conditions Summary

The Water Conditions Summary is an online monthly summary of water conditions in Delaware. Principal factors in determining water conditions are precipitation, streamflow, and groundwater levels in aquifers. Data from rain gages, stream gages, and observation wells located throughout Delaware have been collected and compiled since the 1960s by the Delaware Geological Survey. These data are displayed as hydrographs and are also available for download. In general, water is abundant in Delaware, but supply is restricted by natural geologic conditions in some areas, by contamination in others, and is dependent on precipitation.

Nanticoke River Group

Qnrg

The Nanticoke River Group consists of the Turtle Branch and Kent Island Formations. The Nanticoke River Group consists of heterogeneous units of interbedded fine to coarse sand, clayey silt, sandy silt, and silty clay. Where the units are muddy, downstream of Seaford, the sequence consists of a lower fluvial to estuarine swamp to tidal stream deposits (coarse sand to gravelly sand with scattered organic-rich muddy beds) overlain by estuarine clayey silts and silty clays that contain rare to common Crassostrea (oyster) bioherms. The silts and clays are overlain by sands with clay laminae, to fine to coarse well-sorted, clean sand that are estuarne beach and eolian in origin. Upstream, the mud beds are rarer and restricted to the west side of streams and consist of organic rich clayey silt. Most of the stratigraphic section is dominated by clean, well-sorted sands.

Assawoman Bay Group

Qabg

The Assawoman Bay Group consists of the well-sorted sands, silts, and clays of the Omar, Ironshire, and Sinepuxent Formations found adjacent to and inland of the Atlantic Coast of Delaware and Maryland. These deposits in Delaware and Maryland were named from oldest to youngest: the Omar Formation (Jordan, 1962, 1964), the Ironshire Formation (Owens and Denny, 1979a), and the Sinepuxent Formation (Owens and Denny, 1979a).

Kent Island Formation

Qki

Owens and Denny (1979) named the Kent Island Formation for deposits bordering the Chesapeake Bay found underneath lowlands that ranged in elevation from 0 to 25 feet in elevation but most of the land surface area is less than 10 feet in elevation. These lowlands are bordered by a scarp with at toe at approximately 25 feet. In its type area, the Kent Island Formation was described as consisting of thick beds of loose, light colored, cross-stratified sand overlying dark-colored massive to thinly laminated clay-silt. Pebbles as much as 10 cm (4 in.) in diameter occur in thin beds with the sand or as scattered clasts in both the sand and clay-silt. Locally, large tree stumps in growth position are encased in the clay-silt. Maximum thickness of the Kent Island was about 12 m (40 feet).