Friday fold: Kyanite quartzite
3 February 2023 06:00 in folds, foliation, Friday Fold, metamorphism, minerals, piedmont, virginia by Callan Bentley
A return to the “video Friday fold” format:
3 February 2023 06:00 in folds, foliation, Friday Fold, metamorphism, minerals, piedmont, virginia by Callan Bentley
A return to the “video Friday fold” format:
2 December 2022 10:00 in boudinage, folds, Friday Fold, metamorphism, piedmont, structure, virginia by Callan Bentley
Two weeks ago was the annual Virginia Geological Field Conference, which was centered this year on the Goochland Terrane, an interesting block of crust in the Piedmont which shows some similarities to the Blue Ridge geologic province, but also shows some differences that suggest it’s not just a mini-Blue-Ridge. One of the best exposures was in Hidden Rock Park, where a series of “whaleback” outcrops expose things like this: There, …
16 September 2022 10:50 in folds, Friday Fold, limestone, ordovician, valley and ridge, virginia by Callan Bentley
This weekend, my family and I traveled to a little agrotainment complex north of Harrisonburg, Virginia, a joint called Back Home On The Farm. It featured a corn maze, hayrides, petting zoo, apple cider donuts, and pumpkin picking. All typical fall frolic; good clean fun. But there were also big blocks of limestone everywhere on the property. I did my best to check them all out. I was mainly scanning …
1 July 2022 15:33 in coastal plain, folds, Friday Fold, maryland, piedmont by Callan Bentley
A quick Friday fold that I observed last month in a boulder of riprap at Chippokes State Park in Surry, Virginia. I have absolutely no idea where this rock was quarried; but it doesn’t look like anything I’m familiar with in Virginia, so maybe the Baltimore Mafic Complex??? Anyhow, it’s not native to the Coastal Plain, but it shows a pleasing fold train of green and gray amid the black …
24 June 2022 10:23 in blue ridge, cleavage, folds, foliation, Friday Fold, neoproterozoic, proterozoic, virginia by Callan Bentley
Happy Friday! Here are some kink-folded metasediments from Virginia’s Lynchburg Group to help usher in the weekend.
15 April 2022 11:38 in alberta, canada, cretaceous, faults, folds, Friday Fold by Callan Bentley
A guest contribution for the Friday fold, from reader Christian Gronau: Christian reports that this is located on the North side of Hwy.11, 20 miles east of Saskatchewan River Crossing, Alberta. Eastern foothills of the Canadian Rocky Mountains. Faulting and folding in Early Cretaceous Luscar Group sediments. Typical repeating sequence of sandstone, siltstone and coal. Thanks for pitching in, Christian! Happy Friday to all!
12 November 2021 11:12 in folds, Friday Fold, sediment, vermont by Callan Bentley
Happy Friday, all! Two shots today from my friend Joe up in Vermont. He sends these from the Champlain Valley, at a place called Raven’s Ridge. It looks like an alternating series of sandstones and shales, arched into an anticline, perhaps during the Acadian Orogeny (??). According to the Nature Conservancy’s website, porcupines live in this anticline, which is called “The Oven.” Looks like most of the strata around there …
25 June 2021 11:17 in blue ridge, folds, Friday Fold, neoproterozoic, proterozoic, virginia, weathering by Callan Bentley
Inside the Blue Ridge (in an 1850s-era railroad tunnel), Callan finds folds and boudinage that formed during Appalachian mountain-building.
11 June 2021 10:33 in analogies, folds, foliation, Friday Fold by Callan Bentley
It’s Friday! Adam Forte, a geology professor at LSU, posted this image yesterday on Twitter: It’s a box of sheets of newsprint, stored vertically and ignored for a while, now rotated 90° so we’re looking at a cross-sectional view. To me, this is an excellent example of a physical analogue modelling experiment (albeit inadvertent) that demonstrates the process by which kink folds form. The key parameters to get this distinctive …
7 May 2021 12:04 in blue ridge, cleavage, folds, foliation, Friday Fold, mass wasting, proterozoic, structure, virginia, weathering by Callan Bentley
On his way to get his COVID vaccine, Callan visits a new outcrop showing folded and faulted strata of the Neoproterozoic Lynchburg Group.