Eureka Quartzite in Mexico?—Tectonic implications

Abstract

Research Article| December 01, 1986 Eureka Quartzite in Mexico?—Tectonic implications Keith B. Ketner Keith B. Ketner 1U.S. Geological Survey, M.S. 939, Federal Center, Denver, Colorado 80225 Search for other works by this author on: GSW Google Scholar Author and Article Information Keith B. Ketner 1U.S. Geological Survey, M.S. 939, Federal Center, Denver, Colorado 80225 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1986) 14 (12): 1027–1030. https://doi.org/10.1130/0091-7613(1986)14<1027:EQIMI>2.0.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Keith B. Ketner; Eureka Quartzite in Mexico?—Tectonic implications. Geology 1986;; 14 (12): 1027–1030. doi: https://doi.org/10.1130/0091-7613(1986)14<1027:EQIMI>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 SocietyGeology Search Advanced Search Abstract At Cerro Cobachi, 90 km east of Hermosillo, Sonora, an Ordovician to Permian miogeoclinal assemblage and an Ordovician to Permian siliceous deep-water assemblage were juxtaposed by thrust faulting between mid-Permian and latest Cretaceous time. Both assemblages resemble counterparts in the Great Basin. One formation, an ultramature quartzite unit in the miogeoclinal assemblage, closely resembles the Middle Ordovician Eureka Quartzite. In the southern Great Basin, isopach lines of the Eureka trend south-southwestward. From a maximum thickness of 134 m near Owens Lake, California, the Eureka thins and splays northward in the southern Inyo Mountains and thins southeastward in the Nopah Range. But south-southwestward, parallel with the isopach lines, it apparently ends abruptly as if faulted. Because the Paleozoic stratigraphy of the western Great Basin and that of west Texas have elements in common, it is quite possible that the southwest-trending facies belts of the Great Basin originally wrapped around the southern border of the continent through northern Mexico and joined corresponding belts in Texas. Two hypotheses are suggested: (1) the Cerro Cobachi terrane, of which the quartzite is a part, is indigenous to northern Mexico, and (2) the Cerro Cobachi terrane is indigenous to California and was displaced tectonically to northern Mexico. The second hypothesis is favored by the apparently abrupt termination of the Eureka Quartzite near Owens Lake, the nearly identical thickness of the two quartzites, and their nearly identical lithic composition and texture. 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.