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.
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 … Read more
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 … Read more
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”]
Another Friday fold from the pre-GSA Superior Craton field trip: Happy Friday. I’m setting this to auto-post on the day that my wife and I arrive in Johannesburg to start our honeymoon. I hope everyone’s doing well in my absence.
…in an Archean schist within the Superior Craton. Same outcrop as the criss-crossing dikes I showed yesterday. We’ve got tourmalines on the plane of foliation in the Setters Schist in Maryland, too, but they aren’t aligned like these Canadian tourmalines; instead the Maryland ones are scattered willy-nilly across the plane of foliation, like pencils on … Read more
A pretty cool outcrop I saw on my pre-GSA structural geology field trip to the Superior Craton: Can you see what caught my eye here? It’s a nice series of cross-cutting relationships. A series of sedimentary rocks were sheared out and metamorphosed, transforming into schists with internal boudins, and then they were cross-cut by first … Read more
Today the Friday fold comes with copious bonus structures. It’s the first stop we hit on Day 3 of the pre-GSA Minneapolis field trip to examine the structural geology of the subprovince boundaries within the Superior Craton. This particular site showed granitoid dikes that had been deformed during dextral transpression into a variety of structures … Read more
Sorry to be late with this – I think that’s the first time I’ve forgotten to post a Friday fold. Blame it on the tryptophan.
Okay – in spite of numerous distractions (see every other post so far this week), it’s time to return to the pre-GSA Minneapolis structural geology field trip. Our final stop of the second day in the field was a series of folded up mafic metavolcanics. I’ve got some photographs of them. These mafic volcanics were … Read more