Thanks for the all the links. My wife and I have been talking about going on a road trip that way sometime, your info will come in handy, and probably drive my wife nuts with my side trips to view new geology.
As it turns out, a recent project of mine has me deeply involved in understanding the geologic history of the Central Appalachian area, which is closely related to the Ouachita history. It is amazingly complex, trying to unravel three major metamorphic and deformational events, and that's just the compressional tectonics. The stratigraphy of the rifted margin and foreland basins is still debated. But I see similar structures there in Texas that I see in Virginia, but without the metamorphism. What a range of mountains they must have been!
The blue quartz I've only seen as very small phenocrysts in what we would call "quartz-eye" rhyolites. Never seen them this big, or with the Kspar phenos.
Space/Science » in reply to Llanite
I'm gonna bookmark that one, REB.