Friday fold: tension gashes near Sunflower, Arizona

Reader John Christian shared these folds with me via email last week. They are quartz veins in slightly metamorphosed Precambrian igneous rocks found near Sunflower, AZ in the Mazatzal Mountains. The second photo is a close-up shot of the curviest, cleanest batch of folds from the first shot. These are beautiful examples of folds in … Read more

Friday fold: Noonday Dolomite in Mosaic Canyon

Because I’m putting together a field course for spring break 2020 to Death Valley California, I was looking through old Death Valley photos this week, from the last time I went to that special place. It was seven years ago! How time flies… This one is in Mosaic Canyon, and was taken by my student … Read more

Friday fold: two samples from Tennessee Tech

I spent some time in east central Tennessee last week, visiting the Earth Sciences department at Tennesee Technical University in their lovely newly-remodeled home on the main campus quad. In a hallway display case, they had many beautiful specimens on display to educate and inspire. Here are two lovely examples of folding. Terrific rocks to … Read more

Friday folds from the Foreknobs Formation

TGIF! That’s my seven year old field assistant showing off the shape of a syncline in shale, siltstone, and fine sandstone of the Foreknobs Formation, a Devonian nearshore package of clastic sediment in the Valley & Ridge Province of eastern West Virginia. Want to see something freaky for Halloween? Photoshop can make it happen: Ewwww. … Read more