Fri, 25 Jul 2014 23:00:21 +0000
Kink folds, or chevron folds. Rocks units being compressed due to stress can fold into beautiful shapes. Chevron folds specifically form when the rock unit is composed of alternating layers of relatively "tough" and relatively "weak" rock.
Recumbent chevron folds in Early Pennsylvania graywacke and shale of the Bude Formation at Millook Havem on the north coast of Cornwall, southwestern Britain, record the development and deformation of the Varsican foreland basin -- testifying to the closure of the Rheic Ocean during the mid- to Late Pennsylvanian Variscan orogeny. From: GSA Today, Vol. 18, No. 12 (Dec.2009)