You are browsing the archive for Friday Fold Archives - Mountain Beltway.

22 April 2016

Friday fold: Crumpled Dinwoody Formation, Sheep Mountain, Wyoming

Today for your folding pleasure, I give you two field GigaPans shot by Jeffrey Rollins, a two-time Rockies field course alumnus and Old Dominion University student working under my colleague Declan De Paor, assisted by NOVA student Bridget Gomez, during last summer’s extended GigaPan expedition at the Sheep Mountain Anticline, Wyoming. This particular outcrop was found near the axis of the massive Laramide fold, and shows an extensively deformed section …

Read More >>

No Comments/Trackbacks >>


15 April 2016

Friday fold: Shiny pahoehoe

Friday fold: Shiny pahoehoe

James Farrell is our newest Friday fold source. Today he shares a primary (not tectonic)  fold – the fold is in the ropy texture of a pahoehoe flow: Those colors! What a gorgeous rock. Thanks for sharing, James! You, too, can share your folds here. Send me your images. I look forward to featuring them on the Friday fold!

Read More >>

No Comments/Trackbacks >>


11 March 2016

Friday fold: disharmony in the Old Lyme Gneiss

Friday fold: disharmony in the Old Lyme Gneiss

Happy Friday – it’s the end of a very busy week for me, and I hope you too are looking forward to a fun and rejuvenating weekend. Here’s your Friday fold – like last week, a guest submission from Joe Kopera: Wowzers; that’s a looker! What are we looking at here? Joe writes: This photo shows geologic mapper and structural geologist Greg Walsh (USGS) explaining disharmonic folding to assembled geologists …

Read More >>

2 Comments/Trackbacks >>


4 March 2016

Friday fold: Mount Monadnock, New Hampshire

Friday fold: Mount Monadnock, New Hampshire

It’s Friday, so in search of an appropriate fold, Joe Kopera leads us to the top of New Hampshire’s Mt. Monadnock. Bonus: boudinage!

Read More >>

No Comments/Trackbacks >>


26 February 2016

Friday fold: Siccar Point video from BGS

Friday fold: Siccar Point video from BGS

The British Geological Survey just came out with a new video on Siccar Point, featuring some excellent drone video of the site (in very good weather!). In addition to the unconformity, one of the things you will appreciate about the video is an excellent end-on view of a plunging synform exposed just above waterline: You’ll get a much better sense of its shape by enjoying the motion of the drone’s …

Read More >>

1 Comment/Trackback >>


19 February 2016

Friday fold: Catalina Island #3

Friday fold: Catalina Island #3

Happy Friday – sorry to have not shared any folds with you last week. I hope these beautiful folds in Catalina Island meta-cherts will make up for it: As with the previous couple of Friday folds, this image is courtesy of Sarah Penniston-Dorland (University of Maryland, College Park).

Read More >>

No Comments/Trackbacks >>


5 February 2016

Friday fold: Catalina Island #2

Friday fold: Catalina Island #2

Happy Friday! Here’s another fold from Catalina Island, California – an antiform in metasediments, courtesy of Sarah Penniston-Dorland of the University of Maryland:

Read More >>

5 Comments/Trackbacks >>


29 January 2016

Friday fold: Catalina Island #1

Friday fold: Catalina Island #1

My friend Sarah Penniston-Dorland, of the University of Maryland, supplied this week’s Friday fold. it comes from Catalina Island, California, where Sarah just wrapped up some field work with two of her students. All three of them have given me permission to post the images here: The Catalina Schist is a suite of subduction-related metamorphic rocks. These rocks are amphibolite facies gneisses, but part of the Catalina Schist. The metamorphic …

Read More >>

No Comments/Trackbacks >>


15 January 2016

Friday fold: Harpers Ferry

Friday fold: Harpers Ferry

The geology east of Harpers Ferry, West Virginia, is cool. It’s Blue Ridge rocks, from basement to the cover sequence, tilted to the west and broken and repeated by the Short Hill Fault. Here’s a look at a detail of the Geology of the Harpers Ferry quadrangle by Southworth and Brezinski (1996). So there’s a fault! Good – but the title of this post isn’t “Friday fault” – Where’s the …

Read More >>

No Comments/Trackbacks >>


8 January 2016

Friday fold: Cho La Pass, Himalayas

Friday fold: Cho La Pass, Himalayas

Today’s Friday fold comes from Martin Schmidt, who has shared a few previous folds with Mountain Beltway readers. It shows a folded ptygmatic vein from the Himalayas. Pretty sweet, amiright? Thanks, Martin. Happy Friday, all!

Read More >>

4 Comments/Trackbacks >>