Large-Scale Exfoliation in Massive Sandstones of the Colorado Plateau

Abstract

Research Article| May 01, 1963 Large-Scale Exfoliation in Massive Sandstones of the Colorado Plateau WILLIAM C BRADLEY WILLIAM C BRADLEY Dept. Geology, University of Colorado, Boulder, Colo Search for other works by this author on: GSW Google Scholar Author and Article Information WILLIAM C BRADLEY Dept. Geology, University of Colorado, Boulder, Colo Publisher: Geological Society of America Received: 11 Jun 1962 First Online: 02 Mar 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Copyright © 1963, The Geological Society of America, Inc. Copyright is not claimed on any material prepared by U.S. government employees within the scope of their employment. GSA Bulletin (1963) 74 (5): 519–528. https://doi.org/10.1130/0016-7606(1963)74[519:LEIMSO]2.0.CO;2 Article history Received: 11 Jun 1962 First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation WILLIAM C BRADLEY; Large-Scale Exfoliation in Massive Sandstones of the Colorado Plateau. GSA Bulletin 1963;; 74 (5): 519–528. doi: https://doi.org/10.1130/0016-7606(1963)74[519:LEIMSO]2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract Massive igneous and metamorphic rocks commonly display a near-surface sheet jointing that is unrelated to other structures and textures but is related to topography in that it exists only at shallow depths and tends to parallel the surface of the ground. Most authors believe that this large-scale exfoliation accompanies expansion when erosion releases confining pressure on rocks which were once deeply buried. Confining pressure is released unequally, enabling residual compressive stresses parallel to the surface to cause the splitting. Little has been written about these structures in sedimentary rocks.Massive sandstones on the Colorado Plateau flake off in sheets bounded by joints which are unrelated to other structures and textures, which are found only at shallow depths, and which are oriented parallel to the outcrops. This large-scale exfoliation is similar in all important aspects to that found in crystalline terranes and it has been produced in the same way—by differential residual stresses resulting from erosion, particularly canyon cutting, of rocks that were once buried. Exfoliation has contributed to canyon development and has led to such distinctive topographic features as exfoliation caves and domes. Most existing exfoliation joints are probably of Pleistocene age. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.