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23 June 2017

Friday fold: Canoeing the Célé River, France

Friday fold: Canoeing the Célé River, France

I was in southern France last week, exploring an awesome suite of caves cut into the Causses limestone plateau. My family and I took an afternoon to paddle a canoe down 5 kilometers of the Célé River. While floating along, we spied a gentle, open fold in the limestone layers that crop out along the banks. This low-amplitude fold is highlighted with the “horizontal” reference line of the river’s edge. …

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16 June 2017

Friday fold: toothpasty Tomstown

Friday fold: toothpasty Tomstown

I spent last weekend at the National Association of Geoscience Teachers’ Eastern Section meeting, based out of the Community College of Baltimore County in Catonsville, Maryland. One of the two field trips I took headed out to the western Piedmont, Blue Ridge and Valley & Ridge provinces of western Maryland. On that trip, we took a tour of Crystal Grottoes, a commercial cave south of Boonsboro. I was impressed at …

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9 June 2017

Friday fold – or is it a fauxld?

Friday fold - or is it a fauxld?

Check this out: is it a fold? Annotated to show the 3D expression of the ‘bed’ (left) and cross-sectional view (right): Here’s a 3D model of the outcrop to better convey its shape: This is in the same sandstone unit I blogged about on Tuesday with the apparent soft-sediment deformation. This could be another example of the same general class of pre-lithification structures, or it could be an optical illusion. …

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26 May 2017

Friday fold: Macigno turbidites II

Friday fold: Macigno turbidites II

It’s Friday. We return to Italy’s Macigno Formation for a fold, courtesy of blog reader Samuele Papeschi.

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5 May 2017

Friday fold: sea monster in stone

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.

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28 April 2017

Friday fold: Two more from the Lewisian gneiss of Scotland

Friday fold: Two more from the Lewisian gneiss of Scotland

Happy Friday! Here are two more folds in gneisses of the Lewisian, in the North West Highlands of Scotland, near Tarbet. Enjoy!

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21 April 2017

Friday (coal)d

Friday (coal)d

Often I feature a fold photo here on Friday, but today I give you a folded coal, so therefore a “coald” – this is from the Pennsylvanian Conemaugh Formation on the Alleghany Plateau in West Virginia, near Bismarck. Photo by Sebastian Andres Kaempfe Droguett.

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7 April 2017

Friday fold: paper demo

Friday fold: paper demo

The Friday fold is a sheet of paper. Yes, really!

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10 March 2017

Friday fold: Sheba Mine sample

Friday fold: Sheba Mine sample

When touring the geology of the Barberton Greenstone Belt last August, our group visited the Sheba Mine, a gold mine high in the hills. Their geologist kindly showed us around and allowed us to visit his history-laden office. I have no idea where this sample originated, but it was the only fold I saw in the place, nestled between sepia-toned photographs and old lanterns and rusty picks. I wonder what …

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3 March 2017

Friday fold: Kink folded Dalradian metasediments

Let’s reminisce back to the Walls Boundary Fault on the Ollaberry Peninsula of Shetland today. Here’s a 3D model to go along with the ones I posted last time: It’s a little ragged, but so am I at the end of the workweek! Happy Friday. Have fun spinning this thing.

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