Friday fold: the Brooks Range, Alaska
It’s Friday, thank goodness. Today our “Friday fold” feature heads north, way north, to the Brooks Range of Alaska. There we find a trio of mountainsides exposing folds photographed in the 1990s.
sediment
Friday fold: the Devil’s Backbone and its neighbor
It’s Friday; time to stretch our backbones out in anticipation of the weekend. Let’s look to a backboney-named Friday fold for a little inspiration… …And what’s that, just down the road? Another fold, in need of a catchy name…
Friday fold: Ferruginous sediments in Barberton Mountain Land
A trip back to Archean sedimentary rocks in Barberton, South Africa, reveals a few folds on the roadside…
Friday folds: Continuing contorted Conestoga carbonates
The first Friday of September calls out for a fold. The Burle Business Park in Lancaster, Pennsylvania has an answer – several of them, in fact!
Friday fold: new folds from the Empire Formation, Glacier National Park
Hiking Siyeh Pass in Glacier in Glacier National Park on Tuesday with my Montana State University field course, we spotted a few new folds in the Empire Formation (a transitional unit between Helena Formation and Grinnell Formation). Here is one of the students serving as a sense of scale, with interesting features on either side … Read more
Friday fold: twisted turbidites at Usal Beach
Last week, I spent two perfect days camping with family at Usal Beach, in Mendocino County, California. Along the beachside cliffs there, I spotted plenty of lovely turbidites: graywacke and shale and a little bit of conglomerate that had been scraped off the subducted Farrallon Plate to help contribute to the bulk of the Franciscan … Read more
Deformed conglomerate of Frog Lakes, California
Fifteen years after mapping deformed rocks of the Sierra Crest shear zone system in the high Sierra, a family vacation brings Callan back to the pre-batholith metasedimentary rocks which show a pronounced strain.
Friday fold: a quartet from Marli Miller’s website
Marli Miller is a senior instructor at the University of Oregon. She is the author of Roadside Geology of Oregon and (with Darrel Cowan) Roadside Geology of Washington. She’s also a very talented geological photographer. She launched a website recently to showcase her work and make it available for instructors: Geology Pics. After chatting with … Read more
2/3 pass rate on determining geopetal “up”
A visual challenge via Twitter to determine stratigraphic younging direction ends with equivocal results. So let’s use GIGAmacro imagery to school your sedimentological students on how three primary sedimentary structures look different right-side-up versus up-side-down.
Friday fold: Isoclinal in Damaraland
A guest Friday fold from Graham Andrews of West Virginia University: Graham describes this as an almost along axis view of a huge isocline in the Damaraland belt, Namibia Thanks for sharing! And a happy Friday to all.