3 August 2018
Today we feature a
famous recumbent, chevron anticline near Hill City, South Dakota has been featured as a Friday Fold or not, but thought I would give it a go. The rocks are Proterozoic metagreywacke turbidites with 70 complete or partial Bouma sequences. This is believed to be a late (D4) fold in the Black Hills related to upward doming associated with the emplacement of the Harney Peak Granite, which is in the sub-surface. See p. 24 of Redden and DeWitt (2008, USGS Scientific Investigations Map 2777) for more info.
courtesy of Kent Ratajeski of the University of Kentucky. Thanks for sharing, Kent!