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Site content related to keyword: "Sussex County"

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

Stream Station: Nanticoke River near Bridgeville

USGS 01487000 NANTICOKE RIVER NEAR BRIDGEVILLE, DE

Station Type: 
Stream
Period of Record: 
April 1943 to Present
Frequency: 
Monthly
Map County: 
Sussex County
Map Location: 
38.728333, -75.561861

Digital Water-Table Data for Sussex County, Delaware (Digital Data Product No. 05-01)

Digital Water-Table Data for Sussex County, Delaware

This digital product contains gridded estimates of water-table (wt) elevation and depth to water (dtw) under dry, normal, and wet conditions for Sussex County, Delaware. Files containing the point data used to create the grids are also included. This work is the final component of a larger effort to provide estimates of water-table elevations and depths to water for the Coastal Plain portion of Delaware. Mapping was supported by the Delaware Department of Natural Resources and Environmental Control and the Delaware Geological Survey.

These grids were produced with the same multiple linear regression (MLR) method as Andres and Martin (2005). Briefly, this method consists of: identifying dry, normal, and wet periods from long-term observation well data (Nc45-01, Ng11-01, Qe44-01); estimating a minimum water table (Sepulveda, 2002) by fitting a localized polynomial surface to elevations of surface water features (e.g., streams, swamps, and marshes); and computing a second variable in the regression from water levels observed in wells. A separate MLR equation was determined for dry, normal, and wet periods, and these equations were used in ArcMap v.9 (ESRI, 2004) to estimate grids of water-table elevations and depths to water. Grids produced in this project were merged with those previously completed for eastern Sussex and smoothed to minimize edge effects.

Thousands come out to celebrate the sea at Coast Day 2009

Coast Day visitor Brandon Herbert Mears at the ever popular critter touch tanks. Photo by Lisa Tossey

A 33-year tradition, Coast Day lets visitors learn more about the state's ocean and coastal resources as well as the work of CEOE researchers, Delaware Sea Grant, and their many partners.

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.

Groundwater affected by development, scientists say

Groundwater is both the source of drinking water and the method of disposing of wastewater, said Scott Andres, hydrogeologist with the Delaware Geological Survey. There is plenty of water to be had, he said, but the challenge is protecting public and environmental health.

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.

MS4 Seismic Stratigraphy Along Three Multichannel Seismic Reflection Profiles off Delaware's Coast (Front and Back Pages)

Seismic Stratigraphy Along Three Multichannel Seismic Reflection Profiles off Delaware's Coast

Three multichannel, common-depth-point (CDP), seismic reflection profiles were run off Delaware's coast for the Delaware Geological Survey. Their purposes were (1) to determine the depth to the unconformity (post-rift unconformity) at the base of the nearshore submerged Coastal Plain sedimentary rocks and (2) to relate onshore with offshore
geology as interpreted from the U. S. Geological Survey's network of regional seismic profiles. In addition, the nearshore profiles reveal considerable detail about the nature of the Neogene lithostratigraphic units and aquifers within them that supply water to the coastal communities of Delaware and Maryland (Miller, 1971; Weigle and Achmad, 1982).

Thickness, Elevation of the Base, and Transmissivity Grids of the Unconfined Aquifer of Sussex County (Data Product No. 06-01)

Thickness, Elevation of the Base, and Transmissivity Grids of the Unconfined Aquifer of Sussex County (Data Product No. 06-01)

The unconfined portion of the Columbia aquifer is a key hydrologic unit in Delaware, supplying water to many agricultural, domestic, industrial, public, and irrigation wells. The aquifer is recharged through infiltration of precipitation and is the source of fair-weather stream flow and water in deeper confined aquifers. The aquifer occurs in permeable sediments ranging in age from Miocene to Recent. Over most of Delaware, the top of the unconfined or water-table portion of the Columbia aquifer occurs at depths less than 10 feet below land surface. Because of the permeable character of the aquifer and its near-surface location, the unconfined aquifer is highly susceptible to contamination.

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.

Catalog of Delaware Earthquakes Spreadsheet

Catalog of Delaware Earthquakes Spreadsheet

The occurrences of earthquakes in northern Delaware and adjacent areas of Pennsylvania, Maryland, and New Jersey are well documented by both historical and instrumental records. Over 550 earthquakes have been documented within 150 miles of Delaware since 1677. One of the earliest known events occurred in 1737 and was felt in Philadelphia and surrounding areas. The largest known event in Delaware occurred in the Wilmington area in 1871 with an intensity of VII (Modified Mercalli Scale). The second largest event occurred in the Delaware area in 1973 (magnitude 3.8 and maximum Modified Mercalli Intensity of V-VI). The epicenter for this event was placed in or near the Delaware River. Sixty-nine earthquakes have been documented or suspected in Delaware since 1871.

Kent and Sussex Water Recharge Data (Digital Data Product No 02-01)

Ground-Water Recharge Potential For Kent and Sussex Counties

Ground-water recharge potential maps show land areas characterized by their abilities to transmit water from land surface to a depth of 20 feet. The basic methods for mapping ground-water recharge potential are presented in Delaware Geological Survey Open File Report No. 34 (Andres, 1991) and were developed specifically for the geohydrologic conditions present in the Coastal Plain of Delaware. The digital data for this layer comes from DGS Digital Data Product DP 02-01, Digital Ground-Water Recharge Potential Map Data For Kent and Sussex Counties, Delaware: A. S. Andres, C. S. Howard, T. A. Keyser, L. T. Wang, 2002.

Sussex County Emergency Operation Center (SCOM) Seismic Station

Sussex County Emergency Operation Center (SCOM) Seismic Station. The seismometer, located on the property of the Sussex County Emergency Operation Center, is positioned on the Beaverdam Formation. The Beaverdam Formation is a very coarse sand with beds of fine to medium sand. It is interpreted to be a Pliocene fluvial to estuarine deposit.

RI75 Stratigraphy and Correlation of the Oligocene to Pleistocene Section at Bethany Beach, Delaware

RI75 Stratigraphy and Correlation of the Oligocene to Pleistocene Section at Bethany Beach, Delaware

The Bethany Beach borehole (Qj32-27) provides a nearly continuous record of the Oligocene to Pleistocene formations of eastern Sussex County, Delaware. This 1470-ft-deep, continuously cored hole penetrated Oligocene, Miocene, and Pleistocene stratigraphic units that contain important water-bearing intervals. The resulting detailed data on lithology, ages, and environments make this site an important reference section for the subsurface geology of the region.

Number of Pages: 
47

RI74 Locating Ground-Water Discharge Areas in Rehoboth and Indian River Bays and Indian River, Delaware Using Landsat 7 Imagery

RI74 Locating Ground-Water Discharge Areas in Rehoboth and Indian River Bays and Indian River, Delaware Using Landsat 7 Imagery

Delaware’s Inland Bays in southeastern Sussex County are valuable natural resources that have been experiencing environmental degradation since the late 1960s. Stresses on the water resource include land use practices, modifications of surface drainage, ground-water pumping, and wastewater disposal. One of the primary environmental problems in the Inland Bays is nutrient over-enrichment. Nitrogen and phosphorous loads are delivered to the bays by ground water, surface water, and air. Nitrogen loading from ground-water discharge is one of the most difficult to quantify; therefore, locating these discharge areas is a critical step toward mitigating this load to the bays. Landsat 7 imagery was used to identify ground-water discharge areas in Indian River and Rehoboth and Indian River bays in Sussex County, Delaware. Panchromatic, near-infrared, and thermal bands were used to identify ice patterns and temperature differences in the surface water, which are indicative of ground-water discharge. Defining a shoreline specific to each image was critical in order to eliminate areas of the bays that were not representative of open water. Atmospheric correction was not necessary due to low humidity conditions during image acquisition. Ground-water discharge locations were identified on the north shore of Rehoboth Bay (west of the Lewes and Rehoboth Canal), Herring and Guinea creeks, the north shore of Indian River, and the north shore of Indian River Bay near Oak Orchard.

Number of Pages: 
17

RI70 Thickness and Transmissivity of the Unconfined Aquifer of Eastern Sussex County, Delaware

RI70 Thickness and Transmissivity of the Unconfined Aquifer of Eastern Sussex County, Delaware

The unconfined portion of the Columbia aquifer is a key hydrologic unit in Delaware, supplying water to many agricultural, domestic, industrial, public, and irrigation wells. The aquifer is recharged through infiltration of precipitation and is the source of fair-weather stream flow and water in deeper confined aquifers. The aquifer occurs in permeable sediments ranging in age from Miocene to Recent. Over most of Delaware, the top of the unconfined or water-table portion of the Columbia aquifer occurs at depths less than 10 feet below land surface. Because of the permeable character of the aquifer and its near-surface location, the unconfined aquifer is highly susceptible to contamination.

Number of Pages: 
25