You are browsing the archive for 2012 April.
30 April 2012
Callan shares images of extraordinary boudinage outcrops in strained Archean meta-basalts on the Quetico-Wabigoon subprovince boundary within the southern Superior Craton. Ogle these gorgeous structures in awe and wonder.
28 April 2012
This week, I took 20 minutes out of my day to have a conversation with a group of students… …in Canada. As you can see, our conversation was not in person, but mediated by the Internet’s video conferencing technology service called Skype. A free Skype account and a video camera allows free, easy video conversations in real time, with people anywhere in the world. It is an absolutely amazing technology, …
27 April 2012
The Friday fold is a contribution from the Massachusetts Geological Survey. It shows a migmatite with lovely structure. An upcoming (free) field trip to this location will be part of the 2012 Structural Geology and Tectonics Forum: an event readers may be interested in attending
26 April 2012
Another shot from my pre-GSA structural geology field trip to the Superior Craton last fall, up in southern Ontario, Canada. The image shows slickenlines coated with brownish fault gouge and oxide staining, cutting through a high-potassium granite (see fresh surface at upper left). The slickenlines are little gouged grooves where asperities (bumps) on the block of rock opposite this one ground into this rock along the fault surface as the …
24 April 2012
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, bearing well-developed axial plane cleavage: Annotated: Close-up of the cleaved central bed:
23 April 2012
Last Saturday, before the rains moved in…
22 April 2012
Once again, we roll around to another Earth Day. I find myself in a more-contemplative-than-normal mood this year, and I’d like to take this opportunity to share a bit about what I’ve been thinking. This is a post about the personal side of geoscience – taking data, and its logical implications, and smashing it into life, and seeing what comes out the other side. Two years ago (to the day!), …
20 April 2012
I got this note via email last week. Hi Callan, First of all, congratulations to your blog. It is just great. I would like to contribute to your “Friday fold” section. A few words about myself. I am born in Austria and did my BSc and MSc at the Montanuniversitaet Leoben. In September 2011 I started my PhD here at Monash University (Australia), focusing on 3D implicit modelling of folded deposits …
18 April 2012
Lily and I went out to look at houses last weekend, and I couldn’t help but take some photos of cool rocks I saw along the route. See if you can identify / name / interpret all four: And here’s a bonus: Can anyone tell me what kind of bird built this diminutive nest?