Friday Fold

Friday fold: Isla Escarpada, Chile

by

I’m very nearly delinquent on posting the Friday fold… Here you go – a Google Earth view of a differentially-weathered fold partly above and partly below sea level in Chilean Patagonia, south of Puerto Natales: They call it Isla Escarpada. Awesome. Here’s a Google Maps link if you want to explore it yourself. Happy Friday!

Friday fold: flexed turbidites

by

Spring is almost here! As you get ready for the equinox, enjoy this gentle fold on a Friday: These are turbidites (graywacke and shale) of the late Ordovician Martinsburg Formation, seen in Edinburg Gap, western Massanutten Range, greater Shenandoah Valley, Virginia. Bedding is flexed very slightly here, from moderately-dipping to more steep, and then back … Read more

Friday fold: Mazatzal Orogeny, Arizona

by

Reader Mike Pendergrass contributes this Friday’s fold: I found your blog a couple years ago and I share your love of structural geology.  I did my Master’s Thesis while at Northern Arizona University in the early 80’s and mapped an area on the Mazatzal Mountains of central Arizona.  The Mazatzals in my field area contain … Read more

Friday folds: Three tweets

by

Back at the beginning of January, I asked for help on Twitter for Friday fold fodder. Here are three responses I got: @callanbentley one of my favorites from South Georgia Island. Have more on the laptop. pic.twitter.com/UaRtxM77Vm — John Van Hoesen (@Taconic_Musings) January 8, 2015 @callanbentley 2 folds from my SC Inner Piedmont MS thesis … Read more

Friday fold: Ptygmatic Irving Fm., Colorado

by

Another one from Kim: Kim says: Pygmatic folds in the Precambrian Irving Formation. I think this is 1.7 Ga deformation, late in the Yavapai orogeny, which added various arcs in Colorado to North America. Good place to think about strain ellipses in progressive deformation. Zooming in on the best part, and dialing up the contrast … Read more