Exfoliating granite is a granite undergoing exfoliation, or onion skin weathering (desquamation). The external delaminated layers of granite are gradually produced by the cyclic variations of temperature at the surface of the rock in a process also called spalling. Frost and ice expansion in the joints during the winter accelerate the alteration process while the most unstable loosen external layers are removed by gravity assisted by runoff water.
Exfoliating slabs of granite, on Half Dome in Yosemite National Park, USA
Exfoliating granite, at Enchanted Rock State Natural Area, Texas
Exfoliation joints or sheet joints are surface-parallel fracture systems in rock, often leading to the erosion of concentric slabs.
Exfoliation joints wrapping around Half Dome in Yosemite National Park, California.
Exfoliation joints in granite at Enchanted Rock State Natural Area, Texas, US. Detached blocks have slid along the steeply-dipping joint plane.
Exfoliation joints exposed in a road cut in Yosemite National Park, California.
Exfoliation joints have modified the near-surface portions of massive granitic rocks in Yosemite National Park, helping create the many spectacular domes, including Half Dome shown here.
