Chilhowee Group

Chilhowee Group Stratigraphic range: Cambrian
Type	Group
Underlies	Tomstown Dolomite
Overlies
Location
Region	West Virginia
Country	United States

The Chilhowee Group is a sedimentary body composed of early Cambrian siliciclastic sedimentary rocks which crop out along the eastern margin of the Blue Ridge province in Maryland and Virginia. They represent a rift to passive margin sequence, with mostly coarse, feldspathic sandstones and conglomerates in the lower member and shales and phyllite in the upper members.The Chilhowee Group contains four formations; the Loudoun, Weverton, Harpers and Antietam.<ref>[http://pubs.usgs.gov/bul/b2123/paleo.html Southworth, Another name for the Harpers formations is the Hampton formation, and the Antietam Formation is also known as the Erwin Formation. The Hampton Formation has minor economic importance in the area near the James River Face Wilderness. As of 1982 there were three quarries operating near the James River Face Wilderness. Those quarries produced roofing shale, light weight aggregate, and various materials for brick making. The Antietam Formation also had a minor economic importance, particularly from 1945 up until 1966. There were three quarries producing crushed quartzite, which wa used to produce concrete aggregates, road metal and railroad ballast (Brown 1982).

https://pubs.usgs.gov/mf/1337-D/report.pdf

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