You are browsing the archive for 2015 February.
27 February 2015
Back at the beginning of January, I asked for help on Twitter for Friday fold fodder. Here are three responses I got: @callanbentley one of my favorites from South Georgia Island. Have more on the laptop. pic.twitter.com/UaRtxM77Vm — John Van Hoesen (@Taconic_Musings) January 8, 2015 @callanbentley 2 folds from my SC Inner Piedmont MS thesis mapping field work (1997). biotite gneiss and amphibolite. pic.twitter.com/cnoyzwK3cL — Doug (@dropstones) January 8, 2015 …
24 February 2015
My student Robin has been busy cranking out great new macro GigaPans. Check out a few of these new examples: link link link link link link link link
17 February 2015
Today is the 10-year-anniversary of the day I adopted Lola the cat. She’s been a faithful companion for a quarter of my life! Here’s the day it happened, as recorded in my 2005 calendar: Look at this historical document – Titanic opens; Malcolm Gladwell giving a talk; I was still doing woodcut block printing – and I was teaching structural geology at GMU then, too. Earlier in the same week, …
13 February 2015
Another one from Kim: Kim says: Pygmatic folds in the Precambrian Irving Formation. I think this is 1.7 Ga deformation, late in the Yavapai orogeny, which added various arcs in Colorado to North America. Good place to think about strain ellipses in progressive deformation. Zooming in on the best part, and dialing up the contrast a bit: That’s intense! Seriously strained rocks. What fun!
10 February 2015
Pisolites are large primary concretions that develop in backreef or lagoonal settings such as the Permian Tansil Formation of New Mexico, into which is cut the enormous hole called Carlsbad Caverns.
6 February 2015
Kim Hannula shares a fold today: Kim says: The rocks folded here mostly the Devonian Ouray Limestone. There’s a fault through the outcrop, and another fault to the left of the photo. Regionally, the faults are mapped as normal faults, mostly with the east (right in photo) side down. Locally, that’s not what I see in this outcrop, which makes this a funky place to look at a fold with …