Tholeiitic Basalt Ridge in the Peru Trench

Abstract

Research Article| September 01, 1973 Tholeiitic Basalt Ridge in the Peru Trench L. D. Kulm; L. D. Kulm 1School of Oceanography, Oregon State University, Corvallis, Oregon 97331 Search for other works by this author on: GSW Google Scholar K. F. Scheidegger; K. F. Scheidegger 1School of Oceanography, Oregon State University, Corvallis, Oregon 97331 Search for other works by this author on: GSW Google Scholar R. A. Prince; R. A. Prince 1School of Oceanography, Oregon State University, Corvallis, Oregon 97331 Search for other works by this author on: GSW Google Scholar J. Dymond; J. Dymond 1School of Oceanography, Oregon State University, Corvallis, Oregon 97331 Search for other works by this author on: GSW Google Scholar T. C. Moore, Jr.; T. C. Moore, Jr. 1School of Oceanography, Oregon State University, Corvallis, Oregon 97331 Search for other works by this author on: GSW Google Scholar D. M. Hussong D. M. Hussong 2Hawaii Institute of Geophysics, University of Hawaii, Honolulu, Hawaii 96822 Search for other works by this author on: GSW Google Scholar Geology (1973) 1 (1): 11–14. https://doi.org/10.1130/0091-7613(1973)1<11:TBRITP>2.0.CO;2 Article history first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation L. D. Kulm, K. F. Scheidegger, R. A. Prince, J. Dymond, T. C. Moore, D. M. Hussong; Tholeiitic Basalt Ridge in the Peru Trench. Geology 1973;; 1 (1): 11–14. doi: https://doi.org/10.1130/0091-7613(1973)1<11:TBRITP>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search nav search search input Search input auto suggest search filter All ContentBy SocietyGeology Search Advanced Search Abstract A prominent ridge occurs in the axis of the Peru Trench between 7°25′ to 7°50′ and 8°30′ to 9°30′ S. It rises as much as 900 m above the turbidite fill in the trench axis at 9° 20′ and consists of relatively fresh tholeiitic basalt which is overlain by Pleistocene trench turbidites. The tholeiitic basalt was derived from oceanic layer 2 which has been faulted and uplifted relative to the trench floor as the Nazca lithospheric plate descended into the Peru Trench. A K-Ar date of 8.7 m.y. was obtained on the basalt. This date allows three possible interpretations: (1) that the oceanic crust along the eastern edge of the Nazca plate is younger than indicated by magnetic anomalies; (2) that midplate volcanism has occurred on the older oceanic crust of the Nazca plate; or (3) that the basalt is more weathered and hence older than our data suggest. The second interpretation is preferred within the framework of the existing data. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not currently have access to this article.