You are browsing the archive for 2019 September.
27 September 2019
The western edge of O’Shaughnessy Boulevard, near Glen Canyon Park in San Francisco shows beautiful examples of crumpled cherts. Here are a few dozen photos of these glorious outcrops, and instructions on how to visit.
13 September 2019
AGU’s Chief Digital Officer Jay Brodsky offers up a fresh European fold for you today — and this one is on rather a smaller scale than Jay’s last Friday fold contribution… Click through for a bigger version. These are lovely crinkly folds in highly foliated rocks. I love boxy little crenulations like these. Jay tells me that this is from Graines, Italy, in one of the valleys of the Val …
6 September 2019
Science writer Gabe Popkin shared two fold photos with me this week – both from near Sargans, Switzerland, adjacent to the Rhine River Valley and the border with Lichtenstein. The photos shows the mountain called Gonzen. There, Jurassic limestones crop out in a very wavy pattern: I don’t know the geology of this area in any kind of detail, but I decided to trace out a distinctive upper surface of …