Advertisement

You are browsing the archive for national parks Archives - Mountain Beltway.

14 December 2018

Friday fold: Titus Canyon Anticline

A guest Friday fold brings us to a position in the sky somewhere over eastern Death Valley National Park. Join us in contemplating the Titus Canyon Anticline.

Read More >>

No Comments/Trackbacks >>


26 October 2018

Friday folds: Mather Gorge Formation

It’s been a very Billy-Goaty week for me. Three times since Sunday afternoon, I’ve taken people to the Billy Goat Trail’s “A” loop in C&O Canal National Historical Park. On Tuesday and Thursday, it was my NOVA Physical Geology students. On Sunday, though, it was just my son and me. Good news! He helped me discover a new fold by exploring some new rock outcrops and climbing on them. He …

Read More >>

No Comments/Trackbacks >>


3 November 2017

Friday fold: More kinks from Glacier National Park

This Friday, let’s return to Glacier National Park. Here are some folds in Helena Formation limestone: Can’t see them? Fair enough – the point of maximum inflection appears to be hidden behind a snow-filled gully: But in addition to that big fold, there are several kink bands in there, too. Let’s zoom in: Here they are: Zooming in further, on the right-most of these kink bands: …And here, with the …

Read More >>

No Comments/Trackbacks >>


20 October 2017

Friday fold: Kink folds in Glacier National Park, part II

Over the summer, I treated you to a great big kink fold in the sedimentary rocks of Glacier National Park. Here’s another set: Did you see both of them in that first picture? – one bigger down below, one smaller up above. Both kink bands dip to the left. Let’s zoom in on the upper one: There’s more where this came from – stay tuned for more…. and in the …

Read More >>

No Comments/Trackbacks >>


9 August 2017

A suite of new 3D models

A showcase of five new 3D digital models of awesome rock samples and outcrops, produced using Agisoft Photoscan.

Read More >>

No Comments/Trackbacks >>


28 July 2017

Friday fold: Big kink fold in Grinnell Formation

It’s Friday! How about we celebrate with a beautiful kink fold from a gorgeous national park?

Read More >>

No Comments/Trackbacks >>


5 May 2017

Friday fold: sea monster in stone

It’s Friday, the end of the workweek, but also the beginning of the celebration of folded rocks. Examine a particularly sinuous example from the buckled Cambrian limestones of Canada’s Kootenay National Park.

Read More >>

No Comments/Trackbacks >>


15 April 2017

Basement xenoliths in Catoctin Formation, Compton Pass

My son and I hiked Compton Peak in Shenandoah National Park this morning, and saw these two lovely examples of xenoliths. The example above is small, but it shows clearly the difference between the coarse, felsic basement rock (Mesoproterozoic granitoid, comprising the xenolith) and the surrounding fine-grained dark green metabasalt of the Catoctin Formation (Neoproterozoic). Here’s another, bigger example: These two Blue Ridge examples both illustrate the principle of relative …

Read More >>

No Comments/Trackbacks >>


29 October 2016

New digital media of Shenandoah National Park feeder dikes

In Shenandoah National Park, astride Virginia’s Blue Ridge, feeder dikes of Catoctin Formation (meta-)basalt cut across the Grenvillian-aged granitoid basement. Due to their mafic composition and columnar jointing, these feeder dikes generally weather more rapidly than their host rocks. I led a field trip in the park on Thursday for my son’s school, and my student Marissa was there the weekend prior, checking out the autumn leaves and geology with …

Read More >>

No Comments/Trackbacks >>


16 September 2016

Friday fold: Centenary migmatite

The Friday fold is a guest submission from Bill Burton, who took the photo of these lovely ptygmatic folds in migmatite in a national park on the 100th anniversary of the founding of the Park Service.

Read More >>

No Comments/Trackbacks >>