Callan Bentley We return for today’s Friday fold to a site on the coast of Greenland’s King Oscar Fjord, featured in photographs by Alistair Knock, that first graced Mountain Beltway’s digital pages eight years ago.
Who wouldn’t want to buy that fold?
Quick, awesome Friday fold here from the Canadian Rockies and Maggie Romuld: Maggie also posted another intriguing image of her hiking in the Canadian Rockies – and set geoTwitter abuzz with a discussion of whether she had captured load casts bulging out of the bottom side of a bed or stromatolites projecting upward from the … Read more
The Friday fold erupted out of a volcano, completing the second part of its two stage cooling history, then later got folded and metamorphosed. It was found atop a high cliff near the northern Newfoundland town of St. Anthony.
The ‘Friday fold’ shows gorgeous conjugate sets of kink bands transecting the plane of foliation in some phyllitic metasediments seen on the southern Burin Peninsula of Newfoundland.
Yesterday, I featured some folds from Broom Point, but there are also faults there. With the intriguing local limestone conglomerates providing easily-discernible marker beds, these apparently vertical faults are easy to spot. Here are three examples:
Here’s a look at some of the outcrops at Broom Point, within sight of the famous uplifted fjord called Western Brook Pond: The limestone beds here are Ordovician in age, and they dip to the east: In places through there are folds to be spotted in the beds:
A final Friday fold from Madison, Wisconsin: this one a slab of cut and polished banded iron formation from Australia: What exquisitely beautiful rock! Happy Friday!
Here is an outcrop of folded limestone along route 430 in Newfoundland, inside Gros Morne National Park, just west of the crossroads called Wiltondale: A detailed look at the left antiformal portion of the outcrop: A zoomed-in examination of the rightmost part, where a goopy looking synform resides: Just down the way, a second outcrop … Read more
Traveling in Newfoundland, Callan visits a seaside outcrop showing a Proterozoic submarine slump complex, overprinted by tectonic cleavage and weathered by the sea.
Today’s Friday fold is rendered in stained glass, along with a bunch of other geological details, as seen at the entrance to the geology museum at the University of Wisconsin (site of our previous Friday fold): Beautiful work!
I’m at a workshop in Madison, Wisconsin, this week. I took the lunch hour today and walked over to the geology department to check out their rock garden and geology museum. I was pleased to find a Friday fold in the rock garden: a limestone with cherty nodules/layering that has been folded…. Bonus: some nice … Read more
Last weekend was the annual meeting of the eastern section of the National Association of Geoscience Teachers. On Friday afternoon, we visited Harpers Ferry, West Virginia, and my colleague Beth Doyle led a great field trip to examine the rocks exposed there. This was my favorite outcrop we saw: Here is a close up of … Read more
It’s Friday, and I’m grateful that Bret Leslie of the NRC has stepped up with a Friday fold contribution from coastal California: Bret says this outcrop is: from my trip last month to the Sonoma and Mendocino coast. The first is the cliff below the Pt. Arena lighthouse. The marine deposits (now a marine terrace) … Read more
Naomi Barshi shares this “deskcrop” Friday fold… Naomi says she found this fold: near the Riffelhorn, Gornergrat, above Zermatt, Switzerland. The sample has befriended my other show-off sample of a mantle xenolith from San Quintin, Baja California. Thanks for sharing, Naomi! The xenolith is a nice bonus!
Photoshop is a powerful image editing program. Its “cloning” tool allows the removal of “distracting” data from geological imagery. Examine these four examples and consider the ethical limits of the technique. Is it okay to remove fractures and lichens from an outcrop photo in order to allow novices to focus on the geological content you want them to learn from?
This week, for Friday folds, I offer up some random folds that have passed my perceptual transom this week. First up: In the new Netflix series Our Planet, in episode 7 (Fresh Water), an anticline/syncline pair makes a brief appearance as David Attenborough discusses glaciers as a reservoir for fresh water. Here is a screenshot: … Read more
A book review of one of the runners-up for this year’s Pulitzer Prize for general nonfiction: Elizabeth Rush’s chronicle of modern sea level rise.
When a dike is subjected to shear, how does it deform? A guest Friday fold from Darrel Cowan of the University of Washington teaches a nice little lesson. Join the field trip in Monarch Canyon of Death Valley National Park…
Peter Wohlleben is a forester, managing a forest in Germany. Over decades among the trees, he has had major insights into the “inner lives” of the trees, and uses this book to collate them and share them with a wider audience. The book opens with an anecdote: he walks by some moss-covered lumps in the … Read more
The Friday fold can be found in a boulder of gray chert layers on Black Sands Beach, at Marin Headlands in California.