Often I feature a fold photo here on Friday, but today I give you a folded coal, so therefore a “coald” – this is from the Pennsylvanian Conemaugh Formation on the Alleghany Plateau in West Virginia, near Bismarck. Photo by Sebastian Andres Kaempfe Droguett.
An easter egg on a piece of toast? No, it’s a nice example of Liesegang rings in a slab of sandstone. Explore more in this blog post.
My son and I hiked Compton Peak in Shenandoah National Park this morning, and saw these two lovely examples of xenoliths. The example above is small, but it shows clearly the difference between the coarse, felsic basement rock (Mesoproterozoic granitoid, comprising the xenolith) and the surrounding fine-grained dark green metabasalt of the Catoctin Formation (Neoproterozoic). … Read more
Check this out: That’s a beautiful example of weathering in a dolerite dike on Arran. The igneous rock was broken along two more or less perpendicular joint sets, and then fluid flow along those fractures helped “rot” the adjacent rock through oxidation and hydrolysis. The resulting brownish weathering rind grows at the expense of the … Read more
I did a double-take in the library last week. I was scanning the shelves of audio books, looking for something interesting, when I saw one called The Sixth Extinction. Ahh, such a good book – Elizabeth Kolbert did such a great job with – WAIT – This one has “James Rollins” listed as the author. It … Read more
The Friday fold is a sheet of paper. Yes, really!
The evidence for a meteorite impact origin for the Stoer Group’s Stac Fada member seems to stack up. Engage in a virtual field investigation on Mountain Beltway.
I just discovered a 2015 book that explores the relation between the American landscape to the history of its people, indigenous, enslaved, and enslaver. The author, Lauret Savoy, is a professor at Mount Holyoke College, where she teaches in the department of environmental studies. In the book, Savoy explores the combined history of place and … Read more
Owls are nocturnal birds of prey that eat rodents and grasshoppers, digest the good stuff, and cough up the rest in compressed “pellets” of fur, bone, and chitinous exoskeleton. I found an owl pellet in my yard a few weeks ago, and imaged it using my GIGAmacro Magnify2. I rotated it around to get multiple … Read more
Okay, let’s get this out of the way up front: In no no way is Robopocalypse of anything like the caliber of Our Final Invention or Superintelligence. Though written by an author who holds a PhD in robotics from Carnegie Mellon, this is an adventure novel. It explores some interesting aspects of a AI vs. … Read more