Research Article| January 01, 1938 Laramide igneous sequence and differentiation in the Front Range, Colorado T. S. LOVERING; T. S. LOVERING Search for other works by this author on: GSW Google Scholar E. N. GODDARD E. N. GODDARD Search for other works by this author on: GSW Google Scholar Author and Article Information T. S. LOVERING E. N. GODDARD Publisher: Geological Society of America Received: 22 Jul 1937 First Online: 02 Mar 2017 Online Issn: 1943-2674 Print Issn: 0016-7606 © 1938 Geological Society of America GSA Bulletin (1938) 49 (1): 35–68. https://doi.org/10.1130/GSAB-49-35 Article history Received: 22 Jul 1937 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 T. S. LOVERING, E. N. GODDARD; Laramide igneous sequence and differentiation in the Front Range, Colorado. GSA Bulletin 1938;; 49 (1): 35–68. doi: https://doi.org/10.1130/GSAB-49-35 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 INTRODUCTIONGENERAL FEATURESThe Laramide1 (late Cretaceous—early Eocene) igneous rocks or “porphyries” of the Front Range are largely confined to a belt about 15 miles wide that extends diagonally across the pre-Cambrian core of the range, from Breckenridge northeast to Lyons (Fig. 1). The intrusives show a wide variety both of composition and of form. Dikes are abundant throughout the porphyry belt, but stocks are concentrated along the northwest side, and sills are almost confined to the sediments bordering the pre-Cambrian near Breckenridge and between Lyons and Boulder. South of Boulder, late Cretaceous surface flows and a few dikes and sheets occur near Golden. Co-extensive with the porphyry belt are important ore deposits of lead-silver, gold, gold-telluride, tungsten, and fluorspar.Many contributions have been made on local problems of petrology and petrography, and a few papers dealing with some of the broader regional aspects have been published, notably the . . . 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.