Cross-bedding
From Wikipedia, the free encyclopedia
In geology, cross-bedding refers to inclined sedimentary structures in a horizontal unit of rock; such tilted structures indicate the type of depositional environment, not post-depositional deformation.
Cross-bedding can form in a variety of different environments, though it is most common in stream deposits, as well as in sand dunes; careful study of cross-beds can often determine ancient current or wind directions. Sand dune cross-beds tend to be large, such as in the Jurassic-age erg deposits of the Navajo Sandstone.
[edit] References
- Monroe, James S., and Reed Wicander. The Changing Earth: Exploring Geology and Evolution, 2nd ed. Belmont: West Publishing Company, 1997. ISBN 0-314-09577-2 pp. 113-14.
