Last Sunday morning, two of my former GMU students, Aaron and Alan, led a hike for the GMU Geo-Club to Thoroughfare Gap, a water gap in the Bull Run Mountains of Virginia’s eastern Blue Ridge province. I’ve mentioned the Weverton Formation structures we saw there, and a nice example of a hackle fringe in previous … Read more
Callan joins some students from George Mason University on a field trip to the rock exposures at Thoroughfare Gap, Virginia, where meta-sedimentary rocks are exposed in the eastern Blue Ridge province.
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
The Friday fold takes us to some high-grade metamorphic rocks in the Piedmont of northern Virginia.
Today’s edition of the Friday fold is a cross-section: Doesn’t look too spectacular, does it? — “Why, it’s just a bunch of strata folded into anticlines and synclines,” I’ll bet you’re thinking. But no… it’s actually more complicated than that. We know it’s more complicated by examining geopetal primary structures in the strata. Geopetal structures … Read more
The Friday fold is a series of strata underwater near California’s famed “Mavericks” surf break.
This week’s edition of the “Friday fold” takes us to Route 55 in West Virginia, to deformed Appalachian strata of the Valley and Ridge province. A few bonus structures are also shown — some ripple marks, slickensides, and pencil cleavage.
Norwegian structural geologist Haaken Fossen contributes two incredible images for this week’s Friday fold: a pavement of drastically-shortened banded iron formation from Minnesota, and a trio of three white granitoid dikes, buckled within a gneiss from the Jotun Nappe, in the Norwegian Caledonides. Gorgeous images of gorgeous folds, with links to the rest of Fossen’s collection.
The weekly example of a fold is especially… “cool” this week.
The Friday fold visits the French Broad Massif of North Carolina’s Blue Ridge province.