Structural Study of a Laramide Fold Involving Shallow-Seated Basement Rock, Front Range, Colorado

Abstract

Research Article| February 01, 1970 Structural Study of a Laramide Fold Involving Shallow-Seated Basement Rock, Front Range, Colorado WESLEY E LeMASURIER WESLEY E LeMASURIER University of Colorado, Denver Center, Denver, Colorado 80202 Search for other works by this author on: GSW Google Scholar Author and Article Information WESLEY E LeMASURIER University of Colorado, Denver Center, Denver, Colorado 80202 Publisher: Geological Society of America Received: 07 Apr 1969 Revision Received: 30 Sep 1969 First Online: 02 Mar 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Copyright © 1970, 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 (1970) 81 (2): 421–434. https://doi.org/10.1130/0016-7606(1970)81[421:SSOALF]2.0.CO;2 Article history Received: 07 Apr 1969 Revision Received: 30 Sep 1969 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 WESLEY E LeMASURIER; Structural Study of a Laramide Fold Involving Shallow-Seated Basement Rock, Front Range, Colorado. GSA Bulletin 1970;; 81 (2): 421–434. doi: https://doi.org/10.1130/0016-7606(1970)81[421:SSOALF]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 An anticline three miles west of Loveland, Colorado, exposes Precambrian basement rock, and permits a study of fold mechanisms within the en echelon fold belt of the Colorado Front Range. The contrast in mechanical properties between basement rock and superjacent sediments has resulted in two entirely different mechanisms of folding in this area. Studies of fold geometry, jointing, and stratigraphic thickness indicate that the sedimentary rocks yielded to Laramide stresses by concentric folding, up to a limiting curvature. Thereafter, additional displacements took place by faulting across the steeper limb of the anticline. The relationships of Precambrian structures to the fold geometry indicate that basement adjustments to Laramide stresses took place by differential movement along pre-existing fractures, within a zone adjacent to the unconformity that separates the basement from the sedimentary cover. In the lower basement zone, displacement along high angle reverse faults is virtually the only recognizable feature of Laramide deformation. 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.