Petrology of the Vulcan Peak Alpine-Type Peridotite, Southwestern Oregon

Abstract

Research Article| May 01, 1973 Petrology of the Vulcan Peak Alpine-Type Peridotite, Southwestern Oregon GLEN R. HIMMELBERG; GLEN R. HIMMELBERG 1Department of Geology, University of Missouri, Columbia, Missouri 65201 Search for other works by this author on: GSW Google Scholar ROBERT A. LONEY ROBERT A. LONEY 2U.S. Geological Survey, Menlo Park, California 94025 Search for other works by this author on: GSW Google Scholar GSA Bulletin (1973) 84 (5): 1585–1600. https://doi.org/10.1130/0016-7606(1973)84<1585:POTVPA>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 GLEN R. HIMMELBERG, ROBERT A. LONEY; Petrology of the Vulcan Peak Alpine-Type Peridotite, Southwestern Oregon. GSA Bulletin 1973;; 84 (5): 1585–1600. doi: https://doi.org/10.1130/0016-7606(1973)84<1585:POTVPA>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 alpine-type peridotite in the area of Vulcan Peak, Oregon, is part of the larger Josephine ultramafic complex in the Klamath Mountains geologic province. Partially serpentinized, foliated harzburgite with 15 to 30 percent orthopyroxene makes up approximately 90 percent of the body. The remaining 10 percent is dunite that occurs in the harzburgite as concordant and discordant layers and as irregular bodies. In general, the peridotite at Vulcan Peak is similar in structure, texture, mineralogy, and chemistry to the peridotite at Burro Mountain, California. Structures, textures, and compositions of coexisting phases are consistent with high-temperature (1,000° to 1,200°C) deformation and recrystallization in the upper mantle, and tectonic emplacement into its present crustal position. Evidence to indicate whether the peridotite originated as a refractory residue during partial fusion processes that produced mafic melt or by crystallization from an ultramafic or picritic magma remains inconclusive; poikilitic clinopyroxene enclosing olivine in some dunites, and certain chromitite textures, may represent relict igneous features suggesting a magmatic stage in the history of the peridotite. 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.