Delaware Geologic Information Resource (DGIR) Map Viewer
- Appalachian Piedmont
- Atlantic Coastal Plain
- Cheswold aquifer
- Columbia aquifer
- elevation
- Englishtown aquifer
- Federalsburg aquifer
- Frederica aquifer
- GIS
- hydrogeology
- Manokin aquifer
- Milford aquifer
- Mount Laurel aquifer
- Piney Point aquifer
- Pocomoke aquifer
- Rancocas aquifer
- subsurface
- surficial geology
- technology
- water table
- watersheds
- wells
Data and Graphs of 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.
- aquifer
- Cheswold aquifer
- Cockeysville aquifer
- Columbia aquifer
- Delaware
- Federalsburg aquifer
- Frederica aquifer
- groundwater
- instrumented borehole
- Kent County
- Magothy aquifer
- Manokin aquifer
- Mount Laurel aquifer
- New Castle County
- Piney Point aquifer
- Pocomoke aquifer
- Potomac aquifer
- Rancocas aquifer
- Sussex County
- TAB
- wells
- Wissahickon aquifer
- Interactive
Delaware Groundwater Monitoring Network
- aquifer
- Cheswold aquifer
- Cockeysville aquifer
- Columbia aquifer
- Delaware
- environmental monitoring
- Frederica aquifer
- groundwater
- Magothy aquifer
- Manokin aquifer
- Mount Laurel aquifer
- Piney Point aquifer
- Pocomoke aquifer
- Potomac aquifer
- Rancocas aquifer
- unconfined aquifer
- water resources
- Water Table Aquifer
- wells
First Geologic Map (Statewide Generalized Geologic Map)
- Appalachian Piedmont
- Atlantic Coastal Plain
- bedrock
- Cheswold aquifer
- Columbia Formation
- cross-sections
- Delaware
- Frederica aquifer
- geology
- groundwater
- Hornerstown Formation
- hydrogeology
- Magothy Formation
- Manokin aquifer
- mapping
- Matawan Formation
- Monmouth Formation
- Nanjemoy Formation
- Pamunkey Formation
- Piney Point aquifer
- Pocomoke aquifer
- Potomac Formation
- Rancocas Formation
- subsurface
- Vincentown Formation
Hydrologic Stratigraphic Chart
- aquifer
- Cheswold aquifer
- Columbia aquifer
- Cretaceous Period
- groundwater recharge
- Holocene
- hydrogeology
- Kent County
- Magothy aquifer
- Manokin aquifer
- Milford aquifer
- Miocene
- Mount Laurel aquifer
- Neogene
- New Castle County
- Oligocene
- Piney Point aquifer
- Pliocene
- Pocomoke aquifer
- Rancocas aquifer
- stratigraphy
- Sussex County
- unconfined aquifer
- Upper Cretaceous
- upper Eocene
- upper Holocene
- upper Pleistocene
- upper Pliocene
- Eocene
- Jurassic Period
- Lower Cretaceous
- lower Holocene
- lower Pliocene
- middle Eocene
- middle Pleistocene
- Miocene
- Paleogene
- Pleistocene
- Tertiary Period
- upper Miocene
- lower Eocene
- lower Pleistocene
- middle Miocene
- Paleocene
- Triassic Period
- lower Miocene
- Mesozoic Era
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.
- Beaverdam Formation
- Bethany Beach
- Bethany Formation
- Calvert Formation
- Cat Hill Formation
- Cheswold aquifer
- Choptank Formation
- Columbia Formation
- Federalsburg aquifer
- Frederica aquifer
- Manokin aquifer
- Milford aquifer
- Miocene
- Neogene
- Oligocene
- Omar Formation
- Pliocene
- Pocomoke aquifer
- St. Marys Formation
- stratigraphy
- Sussex County
- upper Pleistocene
- upper Pliocene
- wellhead protection areas
- lower Pliocene
- middle Pleistocene
- Miocene
- Paleogene
- Pleistocene
- Tertiary Period
- upper Miocene
- lower Pleistocene
- middle Miocene
- lower Miocene
RI42 Stratigraphy and Depositional History of the Post-Choptank Chesapeake Group
Onshore and offshore geological and geophysical data were used to investigate the lithostratigraphy, seismic stratigraphy, and depositional history of the late Tertiary age post-Choptank Chesapeake Group rocks in Sussex County, Delaware and adjacent counties in Maryland. The results of this investigation suggest that the St. Marys (?) Formation and the sandy interval of which the Manokin aquifer is a part, are distinct lithostratigraphic units. The Manokin formation is proposed as an informal lithostratigraphic unit that refers to the sandy interval of which the Manokin aquifer is a part. On a regional scale, the section containing the Ocean City and Pocomoke aquifers and adjacent and intervening confining beds is best treated as a single undifferentiated lithostratigraphic unit. The Bethany formation is proposed as an informal lithostratigraphic unit that refers to this section.
RI38 Hydrology of the Manokin, Ocean City, and Pocomoke Aquifers of Southeastern Delaware
Population and accompanying water use are expected to increase by 34 percent in southeastern Delaware between 1975 and 2000. To assess the capability of the aquifers in that area to supply the required amount of ground water, a study of those aquifers was started in 1976. Interpretation of geologic sections developed from drilling and geophysical data showed that the confining beds between the Manokin, Ocean City, and Pocomoke aquifers of Neogene age are thin and discontinuous in some parts of the area. Possible fault zones coinciding with deep tectonic features may also contribute to interconnection of these aquifers. Hydrographs of water levels in the aquifers show differential drawdown during periods of heavy pumping, but levels return to a common altitude during unstressed periods. Because of these characteristics, the Manokin, Ocean City, and Pocomoke aquifers are considered to be a single confined aquifer, in most places.
DGS issues report on the geology of Bethany Beach
- Beaverdam Formation
- Bethany Beach
- Bethany Formation
- Calvert Formation
- Cat Hill Formation
- Cheswold aquifer
- Choptank Formation
- coastal geology
- Columbia Formation
- Federalsburg aquifer
- Frederica aquifer
- Manokin aquifer
- Milford aquifer
- Miocene
- Neogene
- Oligocene
- Omar Formation
- Pliocene
- Pocomoke aquifer
- St. Marys Formation
- stratigraphy
- Sussex County
- upper Pleistocene
- upper Pliocene
- wellhead protection areas
- lower Pliocene
- middle Pleistocene
- Miocene
- Paleogene
- Pleistocene
- Tertiary Period
- upper Miocene
- lower Pleistocene
- middle Miocene
- lower Miocene



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