A Geoscience Digital Image Library

TitleBlack Canyon Gneiss with pegmatite dikes, Black Canyon of the Gunnison National Park
DescriptionNear Gunnison, Colorado, the Gunnison River has eroded a deep canyon into ancient rocks. The walls of the Black Canyon of the Gunnison are made predominately of Precambrian Black Canyon Gneiss. The gneiss is cut by dikes of a pinkish pegmatite. The dikes that are easily seen in this picture run parallel to the foliation of the gneiss, but that is not always the case.
LocationUSA ▹ Colorado ▹ Gunnison. Near Gunnison.
PhotographerDexter Perkins. 1999.
Key wordsgneiss, dike, precambrian, Black Canyon
Tech details511 KB. Vista. Canon EOS Rebel, 55mm, Kodak Elite Chrome 100 ASA.
GeoDIL number1730