Paleomagnetic Correlations and Potassium-Argon Dating of Middle Tertiary Ash-Flow Sheets in the Eastern Great Basin, Nevada and Utah

Abstract

Research Article| June 01, 1972 Paleomagnetic Correlations and Potassium-Argon Dating of Middle Tertiary Ash-Flow Sheets in the Eastern Great Basin, Nevada and Utah C. S GROMMÉ; C. S GROMMÉ U.S. Geological Survey, Menlo Park, California 94025 Search for other works by this author on: GSW Google Scholar E. H McKEE; E. H McKEE U.S. Geological Survey, Menlo Park, California 94025 Search for other works by this author on: GSW Google Scholar M. C BLAKE, JR. M. C BLAKE, JR. U.S. Geological Survey, Menlo Park, California 94025 Search for other works by this author on: GSW Google Scholar GSA Bulletin (1972) 83 (6): 1619–1638. https://doi.org/10.1130/0016-7606(1972)83[1619:PCAPDO]2.0.CO;2 Article history received: 12 Aug 1971 rev-recd: 15 Nov 1971 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 C. S GROMMÉ, E. H McKEE, M. C BLAKE; Paleomagnetic Correlations and Potassium-Argon Dating of Middle Tertiary Ash-Flow Sheets in the Eastern Great Basin, Nevada and Utah. GSA Bulletin 1972;; 83 (6): 1619–1638. doi: https://doi.org/10.1130/0016-7606(1972)83[1619:PCAPDO]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 Directions of natural remanent magnetization are used to identify and correlate individual cooling units in the middle Tertiary ash-flow province in central and eastern Nevada and western Utah. Potassium-argon dating indicates that the minimum time between eruptions of individual but genetically related ash-flow cooling units is on the order of 0.8 m.y. As this interval is long in comparison with the secular variation of the direction of the geomagnetic field, in a given volcanic province the direction of natural thermoremanent magnetization is a unique characteristic of each cooling unit. Ash-flow sheets investigated include the Stone Cabin Formation, the tuff of Pancake Summit, the Windous Butte Formation, the Needles Range Formation, the Bates Mountain Tuff, and the tuff of Clipper Gap, of Oliogcene to early Miocene age. The original areas of individual ash-flow cooling units are as great as 8,000 km2; the volumes, 1,300 km3. The paleomagnetic correlations, made over distances up to 200 km, confirm most of the previously made lithologic correlations and allow more accurate delineation of single cooling units. These correlations are particularly useful in those parts of the Basin and Range province where the Tertiary stratigraphic section consists mainly of ash-flow sheets, and the outcrops are confined to mountain ranges that are separated by alluvium-filled valleys. 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.