Callan gets ready for a summer of travels out in the Rocky Mountains, including teaching a field geology course, participating in a workshop about teaching energy, visiting the Burgess Shale, and… getting married!
I don’t have much time to blog this day/week/month, so here are two stromatolite images from downstream of Grinnell Glacier in Glacier National Park, Montana. This is the same area where I was attacked by a voracious stromatolitic Pac-man, of course. For more on the geology of GNP, see Filip’s post here.
A few microscope photos for you, showing close-ups of feldspars in igneous dikes in the Crazy Mountains of Montana… You’ve seen these rocks before, when I posted a few field photos from this area in August 2009. I took these images of feldspar phenocrysts in a hand sample (from a quartz latite dike) with my … Read more
Friday’s prompt to post the French Thrust shot gave me the opportunity to dig into my “Rockies” folder a bit. Here’s two other shots from my inaugural summer leading my Geology 295 field class out there. Hiking the trail to Grinnell Glacier: …It looks like we’re in the Appekunny Formation here, third from the bottom … Read more
That title sounds kinky, right? Well, calm down. I’m behind the curve on the latest Accretionary Wedge (as I was for the one before that), but here’s a quick image to join the parade of geologic photos that Ann is hosting. While it’s not my favorite, it’s definitely a favorite, more by virtue of the … Read more
Here’s your Friday fold, straight from the canyon of the Jefferson River, near Cardwell, Montana. Perspective is to the south. East is on the left; west is on the right. Bigger version This is right next to the outcrops of LaHood Conglomerate that I mentioned earlier this week. My Rockies course co-instructor Pete Berquist and … Read more
Remember the LaHood Conglomerate? Here’s a few field photos of my Rockies class visiting it last July: Amphibolite clast: Marble clast: I love how well-rounded these clasts can be — like eggs. When these grains were loose cobbles, tumbling down into the Belt Sea, the Earth was only 3 to 3.5 billion years old. The … Read more
Yesterday, I asked for you to evaluate this rock sample of the Belt supergroup and tell me how many structures (both primary and tectonic) that you could identify in it. Thanks to everyone who participated in the discussion. Here’s my annotated copy of that photo for comparison:
Last summer, in Bonner, Montana on my Rockies field course, I took the students to see some nice exposures of Belt Supergroup strata on the side of the road. We were keeping our eyes peeled for both primary structures (i.e., patterns in the sediment that formed at the time of their deposition) and secondary, or … Read more