Long-time readers (and students) know that I have a special corner of my heart reserved for plumose structure and hackle fringes, that finely-filigreed anatomy of a fracture surface. Fractures are everywhere in rocks, and often they show neat little “topographic” details that show fracture propagation direction and stress fields. Here are three that I haven’t yet posted* from more than a year ago, when I spent a week in the Owens Valley of California on an awesome GSA Field Forum:

I’m building up photos faster than I can post them on this blog — I can’t believe these have been sitting in my My Pictures folder for well more than a year. Feel free to discuss.

* At least I don’t think I have. Feel free to search the archives to be sure.