Ch
Harpers Formation (Lower Cambrian); Greenish-brownish-gray phyllite and metasiltstone with light-gray to brown thin-bedded metasandstone
Harpers
Bedrock
Chilhowee
Sedimentary
Bedding
Lower Cambrian
Greenish-brownish gray
Phyllite and metasiltstone with thin-bedded metasandstone
Chilhowee Group Harpers Formation (Lower Cambrian)
Cwo
Owens Creek Member; Dark-gray quartzite and pebble-conglomerate
Owens Creek
Weverton
Dark-gray
Quartzite and pebble-conglomerate
Weverton Formation (Lower Cambrian) Owens Creek Member
Cwm
Maryland Heights Member; Gray quartzite and metasiltstone
Maryland Heights
Gray
Quartzite and metasiltstone
Weverton Formation (Lower Cambrian) Maryland Heights Member
Cwb
Buzzard Knob Member; Light-gray metagraywacke, quartzite, meta-arkose, and metasiltstone
Buzzard Knob
Light-gray
Metagraywacke, quartzite, metaarkose, and metasiltstone
Weverton Formation (Lower Cambrian) Buzzard Knob Member
Clc
Conglomerate; Dark-variegated polymictic quartz pebble and cobble conglomerate
Loudoun
Dark-variegated
Quartz pebble and cobble
Loudoun Formation (Lower Cambrian) Conglomerate
Clp
Phyllite; Dark-variegated phyllite; amygdaloidal, vesicular, and tuffaceous
Phyllite; amygdaloidal, vesicular, and tuffaceous
Loudoun Formation (Lower Cambrian) Phyllite
Zcp
Porphyritic metabasalt
Catoctin
Metamorphic
Ediacaran
Green
Basalt
Catoctin Formation (Ediacaran) Porphyritic metabasalt
Zc
Metabasalt; Green massive to schistose metamorphosed basalt flows
Schistose basalt
Catoctin Formation (Ediacaran) Metabasalt
Zcr
Metarhyolite; Light-gray and tan phyllite and aphanitic quartz-muscovite schist
Light-gray and tan
Phyllite and quartz-muscovite schist
Catoctin Formation (Ediacaran) Metarhyolite