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Site content related to keyword: "Delaware"

United States Geoscience Information Network (USGIN)

United States Geoscience Information Network (USGIN)
Project Contact(s):

The United States Geoscience Information Network (USGIN) initiative is the product of a partnership between the Association of American State Geologists (AASG) and the United States Geological Survey (USGS) created to facilitate discovery of, and access to, geoscience information provided by state and federal geological surveys of the United States. DGS has entered into a partnership with the Arizona Geological Survey (AZGS) to participate in USGIN by establishing a metadata clearinghouse node for Delaware.

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The Earthquake of August 23, 2011

Seismograph recording of the August 23, 2011 earthquake

Delaware and surrounding areas experienced an earthquake event on the afternoon of Tuesday, August 23, 2011. According to the US Geological Survey, a magnitude 5.8 earthquake struck at 1:51 p.m. in central Virginia, in an area referred to as “the Central Virginia Seismic Zone” because of its relatively active earthquake activity for the region. The epicenter was located five miles south-southwest of Mineral, Virginia, with the quake was focused at a depth of 6 km (3.7 miles) below the surface ( The Virginia Geological Survey reports that this is the largest Virginia earthquake known in historic times. A few small aftershocks have occurred in the hours afterward.

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Delaware Groundwater Monitoring Network

The Delaware Geological Survey (DGS) currently monitors groundwater levels in a network of 68 wells in Delaware. Long time-series of water levels in major aquifers serve as critical baseline data for resource management and analyses of aquifer response to pumping, climatic variability, drought hazards, seawater intrusion, and interaction with streams and their ecosystems.

A flood of innovation - UD and the state work together to mitigate coastal flooding in Delaware

Two state agencies, the Delaware Emergency Management Agency (DEMA) and the Delaware Department of Natural Resources and Environmental Control (DNREC), collaborated with the University of Delaware and the Delaware Geological Survey (DGS) and found an answer in the Delaware Environmental Observing System (DEOS). DEOS was created in 2003 as a real-time, regional monitoring system that provides data on weather conditions, water levels, snow depth, and various other environmental factors obtained from automated weather stations in and around the state.

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).

Delaware Geologic Mapping Program (STATEMAP)


The Delaware Geological Survey has a continuing program to map the geology of the entire state at the detailed scale of 1:24,000. The STATEMAP component of the National Cooperative Geologic Mapping Program has contributed significantly to our surficial geologic mapping program. This work has resulted in not only new geologic mapping, but also the digital compilation of previous mapping. Products of this program include file formats that can be downloaded and printed from the web as geologic map products and imported into GIS software as georeferenced layers.

Delaware Geological Survey - US Geological Survey Stream and Tide Gaging Program

The US Geological Survey in cooperation with the Delaware Geological Survey through a State-Federal partnership program operates and maintains stream and tide gages throughout Delaware. The streamgage network is a component of the National Streamflow Information Program (NSIP), a program that provides real-time and long-term current and historical streamflow information that is not only accurate and unbiased, but also meets the needs of many users.

IS7 The Delaware Geological Survey

IS7 The Delaware Geological Survey

IS7 is a foldout brochure that briefly discusses the background and current activities of the DGS. Specifically, the following major programs are listed: Geology, Hydrology, Cartographic Information, Geologic Hazards, Seismograph Network, Outer Continental Shelf, Mineral Resources, Well Records and Sample Library, Publications, and Joint-funded Programs.

IS5 Earthquakes in Delaware

IS5 Earthquakes in Delaware

Delaware is not in a seismically active region but, even here, earthquakes occur because of sudden adjustments in the earth's crust. Even though such movements can be startling they yield important information about the behavior of the earth and the potential for future events. The Delaware Geological Survey continually monitors seismicity in the State because of both the scientific value of the information and to help address the concern of residents and other agencies over possible effects.

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IS1 Delaware Geological Survey Cartographic Information Center

IS1 Delaware Geological Survey Cartographic Information Center

The Delaware Geological Survey Cartographic Information Center has made the DGS a focal point for questions concerning the availability of all types of aerial photography, thematic maps, planimetric maps, topographic maps, historic maps, LANDSAT imagery, space imagery, side looking aerial radar imagery (SLAR), and geodetic control. Sources of maps, charts, aerial photography, boundary mark information, and vertical geodetic control can be obtained for your area of interest within the State through the Center's computer-searchable data bases. In addition, through the Center's affiliation with the U. S. Geological Survey's National Cartographic Information Center (NCIC) in Reston, Virginia, we can locate all cartographic materials covering the United States produced by federal agencies.

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DGS Reinvents Itself on the Web

Screenshot of the new DGS web site
Date: Sep 2010

The Delaware Geological Survey has unveiled a new version of their public web site. Although many of the technologies employed are consistent with modern web standards, giving the user a familiar feel and comfort level, particular attention has been paid to information and the retrieval of it. The site is designed to encourage users to explore content they wouldn't other wise read.

DGS unveils new website

The Delaware Geological Survey has unveiled a new version of their public web site. Although many of the technologies employed are consistent with modern web standards, giving the user a familiar feel and comfort level, particular attention has been paid to information and the retrieval of it.

SP11 Instructions for Preparation of Delaware Geological Survey Data Base Schedules

SP11 Instructions for Preparation of Delaware Geological Survey Data Base SchedulesInstructions for Preparation of Delaware Geological Survey Data Base Schedules

The DGS, in response to the needs for efficient storage, manipulation,retrieval, and report-generating capability, has proceeded with the conversion of the paper file data base to an integrated automated geologic, hydrologic, and mineral resource management information system. It is necessary to organize data in a systematic and standardized fashion for efficient entry into the automated system. To accomplish this, the DGS has made major revisions in the data recording and filing systems.

This report contains the new DGS data schedules, describes the information that should be recorded on each schedule, and presents instructions for preparation of the schedules. The schedules are designed to make various kinds of data consistent with the input format screens utilized in the automated system.

The types of schedules described include:
1. Well
2. Water Level
3. Lithologic Log
4. Sample
5. Aquifer Test
6. Geophysical Log
7. Field Water Quality
8. Laboratory Water Quality
9. OCS Well

A Generalized Geologic Map of Delaware

Generalized Geologic Map of Delaware

The Delaware Geological Survey (DGS) has published the surficial geology of the state of Delaware at a scale of 1:100,000 for New Castle and Kent counties (Ramsey, 2005, 2007). Maps at this scale are useful for viewing general geologic framework on a county-wide basis, determining the geology of watersheds, and recognizing the relationship of geology to county-wide environmental or land-use issues. These maps, when combined with subsurface geologic information, provide a basis for locating water supplies, mapping ground-water recharge areas, and protecting ground and surface water. Geologic maps are also used to identify geologic hazards, such as flood-prone areas, to identify sand and gravel resources, and for supporting state, county, and local land-use planning decisions. Portions of Sussex County have previously been mapped at 1:24,000-scale.

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Web-Delivered Application for Hydrogeologic Data

Project Contact(s):

This project is designed to deliver, by web-based technologies, the most commonly available and requested geologic and hydrologic information used in hydrologic studies required by regulation and ordinance and used by state agencies to support resource-management decisions. Available information can be associated with points or areas. Information associated with points includes descriptive logs, geophysical logs, raw and interpreted groundwater levels, aquifer and geologic unit identification, and hydraulic characteristics of wells. Information associated with areas is either in the form of raster-based (grid) data or polygons. Examples of raster-based data include water-table depths and elevations, tops and thicknesses of geologic and aquifer units, and aquifer transmissivity. Examples of polygons include surficial geology and groundwater recharge potential.

The intent of developing a web-technology enabled system is to provide a more intuitive and comprehensive toolset for locating, quickly viewing, and downloading the desired information in an efficient, extensible, and familiar manner.

MS1 Availability of Earth Science Maps in Delaware (Out-Of-Print)

MS1 Availability of Earth Science Maps in Delaware

Map showing the types of Earth science maps that are available from State, Federal, and County agencies. Final revision was March of 1990. This publication is now Out-Of-Print.

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Presentation on groundwater availability

John Talley, of the Delaware Geological Survey, made a presentation titled “Groundwater Availability, Trends in Water Use, and Potential Conflicts” at the Pickle Packers International spring meeting, Philadelphia, April 15.

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A GIS screening tool for assessing suitability of land for RIBS

Scott Andres and Edward Walther, of the Delaware Geological Survey, presented "Development and Application of a GIS Screening Tool for Assessing Suitability of Land for Rapid Infiltration Basin Systems" at the National Ground Water Association Summit, Denver, April 12-15. Andres also participated in a panel discussion co-sponsored by the U.S. Subcommittee on Groundwater, "National Groundwater Monitoring Network: Listening Session."

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