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.
In support of the University of Delaware's sustainability efforts, the Delaware Geological Survey is offering its First State Geology newsletter as an online document.
First State Geology features news about Delaware geology and water resources, recent DGS publications, and DGS staff activities.
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.
William "Sandy" Schenck lead a field trip through the Delaware Piedmont for the A.I. duPont High School Earth Science Class. The trip made use of the Wilmington-Western Railroad and everyone rode the railroad's "Doodle Bug." Activities included up close examinations of rock and mineral features and even "Panning for Garnets" at Brandywine Springs Park.
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.
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.
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.
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.