Friday, September 2, 2011
This small quartzite boulder, found in morainal deposits between Stella Lake and Teresa Lake below Wheeler Peak in Great Basin National Park, shows cross-bedding defined by dark purplish to reddish laminations. Up appears to be to the left. Without a stratigraphic context it's hard to say whether this quartzite is part of the late Precambrian McCoy Creek Group (pCMc) or the possibly late Precambrian to mostly early Cambrian Prospect Mountain Quartzite (Cpm), but most slopes uphill from this spot are in the Prospect Mountain Quartzite. Depositional environment was likely nearshore to offshore marine.