A Geoscience Digital Image Library

TitleWeathered granite outcrop, Tomichi Valley on U.S. 50, near Parlin, Colorado
DescriptionThese outcrops of Precambrian granite have weathered to form rounded knobs, typical when granite or related rocks are exposed at the Earth's surface for long periods of time. The deep cracks and gullies in the outcrop formed because of joints that allowed water to enter the rock, enhancing mineral decomposition. Sharp corners created by fracturing and jointing only existed temporarily, because weathering and mineral decomposition are more rapid at exposed corners than on flat surfaces.
LocationUSA ▹ Colorado ▹ Gunnison. Near Parlin. View from U.S. 50.
PhotographerDexter Perkins. 1999.
Key wordsgranite, weathering, Colorado
Tech details346 KB. Vista. Canon EOS Rebel, 55mm, Kodak Elite Chrome 100 ASA.
GeoDIL number1775