Group photograph, Elephant Rocks State Park.

Brian does not look too impressed...

Close up of enclave-host relationship.

Spectacular lithophysae in an ~1.5 Ga rhyolite lava flow

Flow banding in an ~1.5 Ga rhyolite lava flow

That's what I call dedication to get to the outcrop...

Complex magma mingling relationships that make this the most interesting riverbed I have ever seen.

Textbook cross-cutting relationships (dike is aplitic).

The mafic component of the local bimodal activity.

It would not be a midwestern geology trip without sedimentary rocks- the Cambrian/Precambrian unconformity. Highly weathered vertical zone is the same mafic dike in previous picture.

Unconformity up close. Dike is cutting the Grassy Mountain ignimbrite, a highly welded ignimbrite.

Running to the outcrop....

Is it is a lava flow or an ignimbrite?

Billy, pay attention....I may have to bring out the chalk!

Jointing in the Graniteville granite (the "Missouri Red").

Group photograph on Taum Sauk Mountain.

Group photograph, Elephant Rocks State Park.