A.I.duPont Students see geology of the Delaware Piedmont
- amphibolites
- Appalachian Piedmont
- Baltimore Gneiss
- Barley Mill Gneiss
- bedrock
- Brandywine Blue Gneiss
- Brandywine Springs
- Clinopyroxene
- Cockeysville Marble
- crystalline rocks
- deformation
- Delaware
- Enstatite (Bronzite)
- fall zone
- Fall Zone
- Faulkland Gneiss
- Garnet
- geology
- Glenarm Series
- Greenbank
- Hornblende
- Hypersthene
- igneous
- magma
- Magnetite
- mapping
- Metapyroxenite and metagabbro (undifferentiated)
- Mica
- Microcline
- Mount Cuba
- Orthoclase
- Orthopyroxene
- pegmatite
- Plagioclase
- Pyroxene
- Quartz
- Red Clay Creek
- Rockford Park Gneiss
- rocks
- Serpentinite
- Setters Formation
- Sillimanite
- Taconic Orogeny
- tectonics
- topography
- Wilmington Complex
- Wissahickon Formation
- Wooddale
- Yorklyn
- Zircon
Baltimore Gneiss
Granitic gneiss with swirling leucosomes and irregular biotite-rich restite layers is the dominant lithology and constitutes approximately 75 to 80 percent of the exposed rocks. The remaining 20 to 25 percent comprises hornblende-biotite gneiss, amphibolite with or without pyroxene, and pegmatite. Granitic gneiss is composed of quartz, plagioclase, biotite, and microcline. Minor and accessory minerals are garnet, muscovite, magnetite, ilmenite, sphene, apatite, and zircon. The hornblende gneiss contains plagioclase, quartz, hornblende, and biotite with/without orthopyroxene. Accessory minerals are garnet, muscovite, clinozoisite, perthitic orthoclase, iron-titanium oxides, sphene, and apatite. Amphibolites are composed of subequal amounts of hornblende and plagioclase with minor quartz, biotite, clinopyroxene, and orthopyroxene.
Deformation in the Piedmont
- Appalachian Piedmont
- Baltimore Gneiss
- Barley Mill Gneiss
- Brandywine Blue Gneiss
- Bringhurst Gabbro
- Christianstead Gneiss
- Cockeysville Marble
- crystalline rocks
- deformation
- Delaware
- Faulkland Gneiss
- folds
- geology
- Iron Hill Gabbro
- Metapyroxenite and metagabbro (undifferentiated)
- Mill Creek Metagabbro
- Montchanin Metagabbro
- New Castle
- New Castle County
- Rockford Park Gneiss
- Serpentinite
- Setters Formation
- Taconic Orogeny
- tectonics
- Wilmington Complex
- Windy Hills Gneiss
- Wissahickon Formation
What are GeoAdventures?
- amphibolites
- Appalachian Piedmont
- arc affinity
- Baltimore Gneiss
- Barley Mill Gneiss
- bedrock
- Brandywine Springs
- Cockeysville Marble
- cross-sections
- deformation
- Faulkland Gneiss
- folds
- gabbro
- geoadventure
- geology
- geomorphology
- Hoopes Reservoir
- igneous
- Metapyroxenite and metagabbro (undifferentiated)
- Mount Cuba
- outcrop
- pegmatite
- Serpentinite
- Setters Formation
- Taconic Orogeny
- Wilmington Complex
- Windy Hills Gneiss
- Wissahickon Formation
- Wooddale
- Yorklyn
A Summary of the Geologic History of Delaware
- Appalachian Piedmont
- Atlantic Coastal Plain
- Baltimore Gneiss
- Calcite
- Cockeysville Marble
- Cretaceous Period
- Dolomite
- Fall Zone
- fossils
- geomorphology
- Miocene
- Neogene
- Oligocene
- Pennsylvanian Period
- Permian Period
- Pliocene
- rocks
- sea level rise
- sediments
- Setters Formation
- stratigraphy
- subsurface
- Upper Cretaceous
- upper Eocene
- upper Pleistocene
- upper Pliocene
- Wilmington Complex
- Wissahickon Formation
- Carboniferous Period
- Eocene
- Jurassic Period
- Lower Cretaceous
- 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
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
GM10 Bedrock Geologic Map of the Piedmont of Delaware and Adjacent Pennsylvania
This is a map of the crystalline bedrock units in the Piedmont of Delaware and adjacent Pennsylvania. The southern boundary of the mapped area is the updip limit of the Potomac Formation (Woodruff and Thompson, 1972, 1975). Soil, regolith, and surficial deposits of Quaternary age are not shown.
- Appalachian Piedmont
- arc affinity
- Arden Granite
- Ardentown Granitic Suite
- Baltimore Gneiss
- Barley Mill Gneiss
- bedrock
- Brandywine Blue Gneiss
- Bringhurst Gabbro
- Christianstead Gneiss
- Cockeysville Marble
- Cretaceous Period
- cross-sections
- Faulkland Gneiss
- Iron Hill Gabbro
- mapping
- Metapyroxenite and metagabbro (undifferentiated)
- Mill Creek Metagabbro
- New Castle County
- Newark
- Pegmatite
- Pennsylvanian Period
- Permian Period
- Rockford Park Gneiss
- rocks
- Serpentinite
- Setters Formation
- Upper Cretaceous
- wetlands
- Wilmington
- Wilmington Complex
- Windy Hills Gneiss
- Wissahickon Formation
- Carboniferous Period
- Jurassic Period
- Lower Cretaceous
- Mississippian Period
- Devonian Period
- Triassic Period
- Silurian Period
- Ordovician Period
- Cambrian Period
- Mesozoic Era
- Paleozoic Era
- Precambrian
GM3 Geology of the Newark Area, Delaware
- Appalachian Piedmont
- Augite
- Baltimore Gneiss
- Cockeysville Marble
- Cretaceous Period
- cross-sections
- Faulkland Gneiss
- Glenarm Series
- Holocene
- Iron Hill Gabbro
- mapping
- Microcline
- Miocene
- Monazite
- Montmorillonite
- Neogene
- New Castle County
- Newark
- Oligocene
- Pegmatite
- Pennsylvanian Period
- Permian Period
- Pliocene
- rocks
- subsurface
- Upper Cretaceous
- upper Eocene
- upper Holocene
- upper Pleistocene
- upper Pliocene
- 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
- Mesozoic Era
- Paleozoic Era
DGS Geologic Map No. 10 (Bedrock Geologic Map of the Piedmont of Delaware and Adjacent Pennsylvania) Dataset
The vector and raster data sets contains the rock unit polygons for the surficial geology for DGS Geologic Map No. 10. This map is of the crystalline bedrock units in the Piedmont of Delaware and adjacent Pennsylvania.
- Appalachian Piedmont
- ArcGIS
- Arden Granite
- Ardentown Granitic Suite
- Baltimore Gneiss
- Barley Mill Gneiss
- bedrock
- Brandywine Blue Gneiss
- Bringhurst Gabbro
- Christianstead Gneiss
- Cockeysville Marble
- cross-sections
- Faulkland Gneiss
- Iron Hill Gabbro
- mapping
- Metapyroxenite and metagabbro (undifferentiated)
- Mill Creek Metagabbro
- New Castle County
- Pegmatite
- Pennsylvania
- Quantum GIS
- Rockford Park Gneiss
- rocks
- Serpentinite
- Setters Formation
- wetlands
- WFS Feature Service
- Wilmington Complex
- Windy Hills Gneiss
- Wissahickon Formation
- 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
Schenck rocks out on railroad geological tours
- Appalachian Piedmont
- Baltimore Gneiss
- Barley Mill Gneiss
- Biotite
- Brandywine Blue Gneiss
- Brandywine Springs
- Bronzite
- Cockeysville Marble
- Cordierite
- education
- Epidote
- Garnet
- geoadventure
- geology
- Greenbank
- Hoopes Reservoir
- Hornblende
- Hypersthene
- Magnetite
- Metapyroxenite and metagabbro (undifferentiated)
- Microcline
- Mill Creek Metagabbro
- Mount Cuba
- Orthoclase
- outreach
- Perkins Run Gabbronorite Suite
- Plagioclase
- Prices Corner
- Quartz
- Red Clay Creek
- Rockford Park Gneiss
- Serpentine
- Serpentinite
- Setters Formation
- Sillimanite
- Wilmington Complex
- Windy Hills Gneiss
- Wissahickon Formation
- Wooddale
- Yorklyn



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