Metarhyolite and Aasociated Pyroclastic Sediments (MDpCAmv;2)

Metarhyolite and Assoicated Pyroclastic Sediments - Metarhyolite - Dense, blue, cryptocrystalline, with white feldspar phenocrysts and glassy quartz; red porphyritic metarhyolite at contact with Catoctin Metabasalt; and Pyroclastic sediments - tuff breccia, blue slaty tuff, white tuffaceous sericitic schist, and banded green slate.

State	Maryland
Name	Metarhyolite and Aasociated Pyroclastic Sediments
Geologic age	Late Precambrian
Original map label	pCmv
Primary rock type	meta-rhyolite
Secondary rock type	schist
Other rock types	slate
Lithologic constituents	Major Metamorphic > Metaigneous > Metavolcanic > MetarhyoliteDense, blue, cryptocrystalline, with white feldspar phenocrysts and glassy quartz; red porphyritic metarhyolite at contact with Catoctin Metabasalt Minor Metamorphic > Metasedimentary > Metaclastic > Slatebanded green slate Metamorphic > Schistwhite tuffaceous sericitic schist
Map references	Cleaves, E.T., Edwards, J., Jr., Glaser, J.D., 1968, Geologic Map of Maryland: Maryland Geological Survey, Baltimore, Maryland, scale 1:250,000.
Unit references	Cleaves, E.T., Edwards, J., Jr., Glaser, J.D., 1968, Geologic Map of Maryland: Maryland Geological Survey, Baltimore, Maryland, scale 1:250,000. Unpublished digital version of the Maryland state geologic map that was digitized by the USGS Water Resources Office in Towson, MD
Geographic coverage	Frederick - Washington