DGS Geologic Map No. 18 (Bethany Beach and Assawoman Bay 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 Series No. 18 (Bethany Beach and Assawoman Bay Quadrangles). 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. An additional dataset of datapoints used to generate rock unit polygons for the surficial geology in the Delaware Coastal Plain covered by DGS Geologic Map Series No. 18 (Bethany Beach and Assawoman Bay quadrangles) exists for use in conjunction with this dataset.
- alluvial deposits
- alluvium and swamp deposits
- Assawoman Bay
- barrier washover deposits
- beach deposits
- Beaverdam Formation
- Bethany Beach
- Bethany Formation
- Carolina Bay deposits
- coastal geology
- dredge disposal deposits
- dune deposits
- dune washovers
- Fenwick Island
- fill
- finger shoal deposits
- lagoon deposits
- Lynch Heights Formation
- marine deposits
- marsh and tidal deposits
- marsh deposits
- nearshore deposits
- Quaternary Period
- sheet sand deposits
- shoreline deposits
- Sinepuxent Formation
- STATEMAP
- surficial geology
- Shapefile
GM18 Geologic Map of the Bethany Beach and Assawoman Bay Quadrangles
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.
- alluvial deposits
- alluvium and swamp deposits
- Assawoman Bay
- Atlantic Coastal Plain
- barrier washover deposits
- beach deposits
- Beaverdam Formation
- Bethany Beach
- Bethany Formation
- Carolina Bay deposits
- coastal geology
- dredge disposal deposits
- dune deposits
- dune washovers
- Fenwick Island
- fill
- finger shoal deposits
- lagoon deposits
- Lynch Heights Formation
- marine deposits
- marsh and tidal deposits
- marsh deposits
- nearshore deposits
- Quaternary Period
- sheet sand deposits
- shoreline deposits
- Sinepuxent Formation
- STATEMAP
- surficial geology
GM14 Geologic Map of Kent County, Delaware
This map shows the surficial geology of Kent County, Delaware at a scale of 1:100,000. Maps at this scale are useful for viewing the general geologic framework on a county-wide basis, determining the geology of watersheds, and recognizing the relationship of geology to regional or county-wide environmental or land-use issues. This map, when combined with the subsurface geologic information, provides 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 to support state, county, and local land-use and planning decisions.
- alluvial deposits
- alluvium and swamp deposits
- Appalachian Piedmont
- Atlantic Coastal Plain
- Beaverdam Formation
- Calvert Formation
- Carolina Bay deposits
- Choptank Formation
- Clayton
- Columbia Formation
- cross-sections
- Dover
- fill
- Holocene
- Kent County
- Lynch Heights Formation
- mapping
- marsh deposits
- Miocene
- Neogene
- Oligocene
- Piney Point Formation
- Pliocene
- rocks
- Scotts Corners Formation
- shoreline deposits
- Smyrna
- St. Marys Formation
- STATEMAP
- surficial geology
- swamp deposits
- Turtle Branch Formation
- undrained depression deposits
- upper Eocene
- upper Holocene
- upper Pleistocene
- upper Pliocene
- Eocene
- lower Holocene
- lower Pliocene
- middle Eocene
- middle Pleistocene
- Miocene
- Paleogene
- Pleistocene
- Tertiary Period
- upper Miocene
- lower Eocene
- lower Pleistocene
- middle Miocene
- lower Miocene
GM13 Geologic Map of New Castle County, Delaware
This map shows the surficial geology of New Castle County, Delaware at a scale of 1:100,000. Maps at this scale are useful for viewing the general geologic framework on a county-wide basis, determining the geology of watersheds, and recognizing the relationship of geology to regional or county-wide environmental or land-use issues. This map, when combined with the subsurface geologic information, provides 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 sinkholes and flood-prone areas, to identify sand and gravel resources, and for supporting state, county, and local land-use and planning decisions.
- alluvial deposits
- Appalachian Piedmont
- Ardentown Granitic Suite
- Atlantic Coastal Plain
- Baltimore Gneiss
- Barley Mill Gneiss
- Brandywine Blue Gneiss
- Bridgeton Formation
- Bringhurst Gabbro
- Bryn Mawr Formation
- Calvert Formation
- Chesapeake and Delaware Canal
- Christianstead Gneiss
- Cockeysville Marble
- Columbia Formation
- Cretaceous Period
- cross-sections
- Delaware Bay Group
- dredge disposal deposits
- Englishtown Formation
- Faulkland Gneiss
- fill
- Holocene
- Hornerstown Formation
- Iron Hill Gabbro
- Lynch Heights Formation
- Magothy Formation
- Manasquan Formation
- mapping
- Marcus Hook
- marsh deposits
- Marshalltown Formation
- Merchantville Formation
- Metapyroxenite and metagabbro (undifferentiated)
- Middletown
- Mill Creek Metagabbro
- Miocene
- Mount Laurel Formation
- Navesink Formation
- Neogene
- New Castle County
- Newark
- Odessa
- Old College Formation
- Oligocene
- Pegmatite
- Pennsylvanian Period
- Perkins Run Gabbronorite Suite
- Permian Period
- Pliocene
- Potomac Formation
- Quaternary Period
- Rockford Park Gneiss
- rocks
- Scotts Corners Formation
- Serpentinite
- Setters Formation
- Shark River Formation
- STATEMAP
- surficial geology
- swamp deposits
- undrained depression deposits
- Upper Cretaceous
- upper Eocene
- upper Holocene
- upper Pleistocene
- upper Pliocene
- Vincentown Formation
- Wilmington
- Wilmington Complex
- Wissahickon Formation
- Carboniferous Period
- Eocene
- Jurassic Period
- Lower Cretaceous
- lower Holocene
- lower Pliocene
- middle Eocene
- middle Pleistocene
- Miocene
- Mississippian Period
- Paleogene
- Pleistocene
- Tertiary Period
- upper Miocene
- Devonian Period
- lower Eocene
- lower Pleistocene
- middle Miocene
- Paleocene
- Triassic Period
- lower Miocene
- Silurian Period
- Ordovician Period
- Cambrian Period
- Mesozoic Era
- Paleozoic Era
- Precambrian
DGS Geologic Map No. 14 (Kent County) Dataset
This data set contains the rock unit polygons for the surficial geology in ESRI shapefile format for DGS Geologic Map No. 14 (Geologic Map of Kent County, Delaware). This map shows the surficial geology of Kent County, Delaware, at a scale of 1:100,000.
- alluvium and swamp deposits
- Appalachian Piedmont
- ArcGIS
- Atlantic Coastal Plain
- Beaverdam Formation
- Calvert Formation
- Carolina Bay deposits
- Choptank Formation
- Clayton
- Columbia Formation
- cross-sections
- Dover
- fill
- Kent County
- Lynch Heights Formation
- mapping
- marsh deposits
- Piney Point Formation
- Quantum GIS
- rocks
- Scotts Corners Formation
- shoreline deposits
- Smyrna
- St. Marys Formation
- surficial geology
- swamp deposits
- Turtle Branch Formation
- undrained depression deposits
- WFS Feature Service
- WMS Map Service
- Shapefile
DGS Geologic Map No. 13 (New Castle County) Dataset
This dataset contains the geologic polygons used for the creation of DGS Geologic Map 13. This dataset shows the surficial geology of New Castle County, Delaware, at a scale of 1:100,000.
- Appalachian Piedmont
- ArcGIS
- Ardentown Granitic Suite
- Atlantic Coastal Plain
- Baltimore Gneiss
- Barley Mill Gneiss
- Brandywine Blue Gneiss
- Bridgeton Formation
- Bringhurst Gabbro
- Bryn Mawr Formation
- Calvert Formation
- Chesapeake and Delaware Canal
- Christianstead Gneiss
- Cockeysville Marble
- Columbia Formation
- cross-sections
- Delaware Bay Group
- dredge disposal deposits
- Englishtown Formation
- Faulkland Gneiss
- fill
- Hornerstown Formation
- Iron Hill Gabbro
- Lynch Heights Formation
- Magothy Formation
- Manasquan Formation
- Marcus Hook
- marsh deposits
- Marshalltown Formation
- Merchantville Formation
- Metapyroxenite and metagabbro (undifferentiated)
- Middletown
- Mill Creek Metagabbro
- Mount Laurel Formation
- Navesink Formation
- New Castle County
- Newark
- Odessa
- Old College Formation
- Pegmatite
- Perkins Run Gabbronorite Suite
- Potomac Formation
- Quantum GIS
- Rockford Park Gneiss
- rocks
- Scotts Corners Formation
- Serpentinite
- Setters Formation
- Shark River Formation
- surficial geology
- swamp deposits
- undrained depression deposits
- Vincentown Formation
- WFS Feature Service
- Wilmington
- Wilmington Complex
- Wissahickon Formation
- WMS Map Service
- Shapefile



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