Portal de Periódicos da CAPES

Mineralogy and Petrology of the Santo Tomas-Black Mountain Basalt Field, Potrillo Volcanics, South-Central New Mexico

1971; Geological Society of America; Volume: 82; Issue: 3 Linguagem: Inglês

10.1130/0016-7606(1971)82[603

1943-2674

Jerry M. Hoffer,

Geological and Geochemical Analysis

Research Article| March 01, 1971 Mineralogy and Petrology of the Santo Tomas-Black Mountain Basalt Field, Potrillo Volcanics, South-Central New Mexico JERRY M HOFFER JERRY M HOFFER Department of Geological Sciences, The University of Texas at El Paso, El Paso, Texas 79900 Search for other works by this author on: GSW Google Scholar Author and Article Information JERRY M HOFFER Department of Geological Sciences, The University of Texas at El Paso, El Paso, Texas 79900 Publisher: Geological Society of America Received: 06 Apr 1970 Revision Received: 21 Oct 1970 First Online: 02 Mar 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Copyright © 1971, 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 (1971) 82 (3): 603–612. https://doi.org/10.1130/0016-7606(1971)82[603:MAPOTS]2.0.CO;2 Article history Received: 06 Apr 1970 Revision Received: 21 Oct 1970 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 JERRY M HOFFER; Mineralogy and Petrology of the Santo Tomas-Black Mountain Basalt Field, Potrillo Volcanics, South-Central New Mexico. GSA Bulletin 1971;; 82 (3): 603–612. doi: https://doi.org/10.1130/0016-7606(1971)82[603:MAPOTS]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 The Santo Tomas-Black Mountain basalts were erupted during the Quaternary from four centers. Six lava flows are present at Black Mountain, three at Santo Tomas, and one each at Little Black Mountain and San Miguel. The basalts are grouped into three major types of phenocryst mineralogy: (l) plagioclase abundant, (2) olivine abundant, and (3) both olivineand plagioclase abundant.All three types are alkali-olivine basalts, showing high alkali-silica ratios and total alkali content increasing with silica.Seven periods of basaltic extrusion among the centers have been established on the basis offieldevidence, phenocryst mineralogy, and pyroxene-olivineratios. K-Ar dates show the basalts to be less than 0.3 × 106 m.y. old.The basalts are thought to have originated from a single small, shallow magma chamber which was under the influence of a high thermal gradient during differentiation. 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.