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
Lynch Heights Formation
Heterogeneous unit of light-gray to brown to light-yellowish brown, medium to fine sand with discontinuous beds of coarse sand, gravel, silt, fine to very fine sand, and organic-rich clayey silt to silty sand. Upper part of the unit commonly consists of fine, well-sorted sand. Small-scale cross-bedding within the sands is common. Some of the interbedded clayey silts and silty sands are burrowed. Beds of shell are rarely encountered. Sands are quartzose and slightly feldspathic, and typically micaceous where very fine to fine grained. Unit underlies a terrace parallel to the present Delaware Bay that has elevations between 50 and 30 feet. Interpreted to be a fluvial to estuarine unit of fluvial channel, tidal flat, tidal channel, beach, and bay deposits (Ramsey, 1997). Overall thickness ranges up to 50 feet.



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