Nature and timing of faulting and synextensional magmatism in the southern Basin and Range, central-eastern Durango, Mexico

Abstract

Research Article| November 01, 1993 Nature and timing of faulting and synextensional magmatism in the southern Basin and Range, central-eastern Durango, Mexico GERARDO J. AGUIRRE-DÍAZ; GERARDO J. AGUIRRE-DÍAZ 1Department of Geological Sciences, The University of Texas at Austin, Austin, Texas 78712 Search for other works by this author on: GSW Google Scholar FRED W. McDOWELL FRED W. McDOWELL 1Department of Geological Sciences, The University of Texas at Austin, Austin, Texas 78712 Search for other works by this author on: GSW Google Scholar GSA Bulletin (1993) 105 (11): 1435–1444. https://doi.org/10.1130/0016-7606(1993)105<1435:NATOFA>2.3.CO;2 Article history first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation GERARDO J. AGUIRRE-DÍAZ, FRED W. McDOWELL; Nature and timing of faulting and synextensional magmatism in the southern Basin and Range, central-eastern Durango, Mexico. GSA Bulletin 1993;; 105 (11): 1435–1444. doi: https://doi.org/10.1130/0016-7606(1993)105<1435:NATOFA>2.3.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 The Nazas area, in the central-eastern portion of the state of Durango, is within the poorly studied southern half of the Basin and Range province in Mexico. At Nazas, high-angle normal faults that cut part of the mid-Tertiary volcanic sequence strike between N 20° and 70° W, with 40% of them between N 40° and 50° W. Tilting of faulted blocks varies from 5° to 35° to the northeast, most commonly around 25° NE. A few blocks are tilted to the southwest as much as 25°. Fault offsets range from 40 m to nearly 300 m. The earliest faulting occurred between 31 and 29 Ma, before the emplacement of mid-Tertiary ash-flow tuffs had ended. The Santa Inés Formation, a widespread fanglomerate, was deposited after the earliest faulting episode and is overlain by 24 to 20 Ma alkalic basalt flows. Although not cut by faults, the flows are adjacent to or cover normal faults. Some of the mapped faults could have been coeval with basalt eruption, as is the case in Trans-Pecos Texas, where alkalic basalt having similar age and composition to that in the Nazas area erupted contemporaneously with normal faulting. The Nazas alkalic basalt also has similar age and stratigraphic position as, but is compositionally distinct from, the Southern Cordilleran Basaltic Andesite (SCORBA), a widespread mafic suite in southwestern North America that has been linked to regional extension. 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.