The Greywacke, by Nick Davidson

Just finished a geologically focused book that the readers of this blog might be interested in. It is a history of work on delineating the early part of the Phanerozoic timescale in Wales and Scotland. The majority of the book is about Adam Sedgewick and Roderick Murchison and their close collaboration and increasing divergence and … Read more

Tension gashes in the Tonoloway Formation

I spent yesterday on Corridor H in eastern West Virginia’s Valley & Ridge province. The rocks here are a mid- to upper-Paleozoic set of strata that record the switch from post-Taconian passive margin sedimentation into Acadian clastic deposition, and then everything is deformed by Alleghanian folding and thrusting. I found myself taking photographs of the … Read more

Kinked metavolcanics of the Castine Formation, eastern Maine

Callan shares a few outcrops from coastal Maine, part of the Avalonia terrane that accreted to ancestral North America during the Acadian Orogeny. They are volcaniclastic rocks, coarse and fine, and showing both overprinting kink bands and cross-cutting basaltic dikes.

Friday fold: Wills Mountain Anticline

Eric Fulmer (who pitched in with last week’s Friday fold) returns this week with another treasure. He writes, I was in Hopeville, WV a couple of years ago. The entire area between Cabins and Hopeville is a real joy (geologically and recreationally) as some of the most resistant rocks of the Mid-Atlantic Appalachians are folded … Read more

Virtual field trip to Siccar Point, Scotland

Time for another virtual field trip on the Geologist’s Grand Tour of the United Kingdom: the most famous outcrop in the world. Today, we visit Siccar Point, Scotland. You’ve probably already seen photos of this place – they usually look something like this: To those who aren’t familiar, here’s what going on: There are two … Read more