Keywords and Phrases
Break-thrust fold; Fold-thrust; Fold-thrust belt leading edge; Mountain belt; Sevier fold-thrust belt; Utah
“The Jurassic to Eocene Sevier fold-thrust belt is the subject of continued scientific curiosity in tectonics, stratigraphy, and industry. Understanding its development in southwest Utah is hindered in part due to the multiple origins proposed for the Kanarra anticline, a major leading edge structure -- a drag fold along the Hurricane fault, Laramide monocline, Sevier fault propagation fold, or a combination of these -- which have confused its tectonic significance and regional context. This confusion results from the structural complexity of its exposed eastern limb, as well as displacement and burial of its crest and western limb beneath Neogene sediments and volcanics along the Hurricane fault. New, detailed bedrock geologic mapping of the central portion of the fold near Kanarraville, Utah and geologic cross sections restored to Cretaceous time (i.e., pre-Basin and Range extension) demonstrate the formation of a composite anticline- syncline pair and fold accommodation thrust faulting are linked in the development of this Sevier structure. A previously unrecognized thrust, the Red Rock Trail thrust, formed due to fold tightening as a “break thrust” in a favorable position to link with the basal detachment. The traditional “Kanarra anticline” is more appropriately termed the “Kanarra fold-thrust system” considering the formation of the Red Rock Trail thrust and other thrusts on the fold. The east verging Red Rock Trail thrust locally presents as a distinctive cataclasite zone in the Navajo Sandstone, which is thrust over the Jurassic Carmel and younger Cretaceous strata. Traceable from Kanarraville to Parowan Gap, this thrust is the leading edge of the Sevier fold-thrust belt in southwest Utah. Stratigraphic relationships constrain the development of the Kanarra fold-thrust system to the Late Cretaceous to Early Eocene (~80 to 50 Ma). Thus the Red Rock Trail thrust records eastward advancement of the Sevier deformation front from the Iron Springs thrust (~100 Ma, coinciding with magmatic flare-ups in the Cordilleran arc and indicating close correspondence between arc-related processes and foreland deformation”--Abstract, page iv.
Hogan, John Patrick
Geosciences and Geological and Petroleum Engineering
Ph. D. in Geology and Geophysics
Missouri University of Science and Technology
Journal article titles appearing in thesis/dissertation
The Kanarra fold-thrust-system: The leading edge of the Sevier fold-and-thrust belt, southwestern Utah
xi, 121 pages
© 2022 William Joseph Michael Chandonia, All rights reserved.
Dissertation - Open Access
Chandonia, William Joseph Michael, "The kanarra fold-thrust system -- The leading edge of the sevier fold-thrust belt, southwest Utah" (2022). Doctoral Dissertations. 3144.