You are browsing the archive for 2012 August.
31 August 2012
The Friday fold, delayed by a week from last week’s contest, appears in Yoho National Park, British Columbia, near the “Natural Bridge” over the Kicking Horse River.
30 August 2012
Here’s a cool outcrop of the Neoproterozoic Miette Group. Most of the Miette is classified as “slate” and “gritstone,” through these particular exposures, on the Icefields Parkway south of Jasper, are fine-grained and lacking in slaty cleavage. They don’t seem to have been too metamorphosed at all right here, as Sebastian shows in this photo: You’re looking (obliquely) up at the bedding plane there, with the bed dipping towards your …
28 August 2012
A guest post by Callan’s student Jacob Douma Traveling with Callan Bentley and Pete Berquist through the Canadian Rockies on their Regional Geology Field Course in July 2012, we were exposed to a variety of physiographic features. Among them, was Red Rock Canyon located 16 km from Waterton Townsite within Waterton Lakes National Park, Alberta. In this guest blog post, I’ll be talking about the canyon’s physiographic features and origins. …
27 August 2012
Here’s the link to the book on Amazon.
26 August 2012
A weekend expedition to GigaPan the C&O Canal’s singular Paw Paw Tunnel results in an exposition on Devonian sedimentation, Alleghanian mountain-building, structural geology, and the incision of the Potomac River to produce entrenched meanders.
23 August 2012
Take a crack at it. I’ll discuss it in full tomorrow later. The blue thing is the handle of a dry-erase marker, to give you a sense of scale.
22 August 2012
Today is the first day of class for the fall semester at Northern Virginia Community College. For the first time in seven years, however, I won’t be in the classroom. For the 2012-13 academic year, I’ll be on sabbatical. Sabbatical is a magic word in my mind. It’s a brilliant idea to allow motivated professors to work on things they wouldn’t ordinarily get the time for, and to take time …
21 August 2012
A few photos from the Canadian Rockies illustrated the characteristic “look” of glacial striations. Callan also demonstrates how they can be used for outright tomfoolery.
20 August 2012
Royal Tyrrell Museum geologist Dave Eberth donates time and expertise to help Callan’s students understand the Cretaceous-aged Horseshoe Canyon Formation in central Alberta.
18 August 2012
Evelyn put up a cat photo on Geokittehs earlier today, and it reminded me of anatexis, the process of partial melting. Anatexis is my favorite way to produce a migmatite. In this model, the light-colored (felsic) ginger cat is derived from the partial melting of another cat, partly dark (mafic) and partly felsic (ginger). Where the low-melting-temperature minerals have been extracted, the source cat is much darker. Fresh injections of …