Research led by the University of Wyoming shows that physical weathering is far more important than previously recognized in the breakdown of rock in mountain landscapes. Because it is difficult to measure, physical weathering has commonly been assumed to be negligible in previous studies.
Cliff Riebe, a professor in UW’s Department of Geology and Geophysics, headed a research group that discovered that climate and erosion rates strongly regulate the relative importance of subsurface physical and chemical weathering of saprolite, the zone of weathered rock that retains the relative positions of mineral grains of the parent bedrock and lies between the layer of soil and harder rock underneath. Saprolite is much like the weathered granite found on the flat areas surrounding the hard granite of Vedauwoo.
“Our work shows that physical strain can no longer be ignored in studies of subsurface weathering. It’s not just a chemical process. It is physical as well,” Riebe says. “What we found is that anisovolumetric weathering is much more common than previously thought, and that variations in this process can be explained by climate and erosion.”
Read more at: University of Wyoming
Brad Carr, a University of Wyoming associate research scientist in geology and geophysics, uses a Geoprobe instrument to sample the subsurface in the foothills of the southern Sierra Nevada in California. Carr contributed to a study that was published in the Jan. 12 issue of Geology. The research shows that physical weathering is far more important than previously recognized in the breakdown of rock in mountain landscapes. (Photo Credit: Sarah Granke)