Friday it was geese. Today, it’s a Clark’s nutcracker: The Clark’s nutcracker is a beefy alpine corvid (perching birds related to crows) of the American west. It’s a great bird in my mind, because if you’re looking at one, it means you’re up in the high country. It means you’re out where the good stuff … Read more
I took my structural geology students to that fine outcrop of the Swift Run Formation in eastern Shenandoah National Park on Friday. There, we saw lovely primary structures with tectonic fabric overprinting (as I have showcased here previously). Consider this graded bed with subsequent (vertical) cleavage: And here’s the hinge of a nice passive fold, … Read more
Last Saturday, before the rains moved in…
Here’s where to get yourself a copy: Smithsonian Institution Secretary, Charles Doolittle Walcott My visit to Walcott’s grave (alluded to in the video) is here. [youtube=”http://www.youtube.com/watch?v=armXHEa4PGo”]
… a brief glimpse of summer in the Rockies: [youtube=”http://www.youtube.com/watch?v=hbRx7W1nYUk”] Footage shot south of Blacktail Butte, in Jackson Hole, looking west towards the Teton Range, in Wyoming. July 2011. Gros Ventre River terrace in the mid-ground.
More pillow-like structures, seen in the Catoctin Formation, on the west side of the Blue Ridge Parkway about ten miles south of Interstate 64. Mini Sharpie for scale – what do you think? They don’t seem to be as strongly fracture-controlled as the Stony Man area “pillows.” But dang, they sure are small… Read the … Read more
Callan and three students visit a world-class outcrop of columnar jointing in Shenandoah National Park.
Today, I share with you eight images that I took yesterday on Skyline Drive in Shenandoah National Park: Blocks of Antietam Formation quartzite (meta-quartz sandstone) of Cambrian age, used in the low rock walls of an overlook parking pull-out. They all bear lovely Skolithos trace fossils (seen end-on, and in cross-section):
After my talk Wednesday night to the Potomac Appalachian Trail Club, I got an email from PATC member Tom Johnson, with an extraordinary photo attached. It shows an exceptional outcrop of the Neoproterozoic Catoctin Formation, exposed atop Compton Peak in northern Shenandoah National Park, Virginia. The outcrop features enormous, well-preserved cooling columns from these ancient … Read more
This summer, a week or two after our wedding, my wife and I found ourselves in the Canadian Rockies for a pre-honeymoon. Part of our time was spent on a backpacking trip to Floe Lake in Kootenay National Park, British Columbia. On our hike in, we passed this outcrop of Chancellor Slate, a Cambrian aged … Read more