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21 June 2022
Another example of overturned bedding
One of my favorite tricks is using bedding / cleavage intersections to identify tectonically inverted strata. On a field trip yesterday to check out soapstone quarries in the Albemarle/Nelson border region, I got to see this lovely example of Lynchburg Group metasediments that showcased a textbook example of the phenomenon: Bedding was initially horizontal, or close to it, and cleavage (formed under tectonic compression) initially vertical. Subsequent deformation rotated the …
18 October 2019
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. Creepy! Another shot of the same fold, with a thick massive sand above a thicker …