Contrast of Opinions Concerning the Formation of the Black Canyon - Continued

Continued from Previous Post

Photo Credit: Nefratiri Weeks

At first, pyroclastic flows directed the course of the river, but over time, its course became set. When it came to the hard Precambrian rocks, it could not change course and began to cut through the hard rocks until it carved the canyon to its current form. This is where geologist Shawn La Bounty disagrees with the USGS explanation.

Shawn explains that the entire region was under an immense amount of strain from tectonic activity and this strain caused the Black Canyon Anticline. He explains, “I do not disagree that this area was blanketed with ash (in fact many times), and this ash may have directed the river in places, especially from Upper Blue Mesa to Curecanti creek, but the placement of the Black Canyon on the top of the Gunnison Uplift (Black Canyon Anticline) was no "Lucky Event"."

"It is widely known that Stress Fractures are caused by the strain hardening of anticlines.” “There are thousands … of scientific journals that explain the common occurrence of this fracturing. Thus the more plausible explanation of the depth and scope of the canyon is that the fractures of the canyon were already in place and the river was simply captured …”

Photo Credit: Nefratiri Weeks

References:

La Bounty, Shawn. Personal Interview. November 18 and 22, 2010.

Black Canyon of the Gunnison National Park & Curecanti National Recreation Area Geologic Resource Evaluation Report. Jan. 2005. National Park Service US Dept of the Interior. http://www.nature.nps.gov/geology/inventory/publications/reports/blca_cure_gre_rpt_view.pdf. Retrieved October 18, 2010.

Johnson, A. The faulting and folding of strain-hardening sedimentary rocks. Tectonophysics, Volume 62, Issues 3-4, 20 February 1980, Pages 251-278.