Peach Springs Tuff: Its Bearing on Structural Evolution of the Colorado Plateau and Development of Cenozoic Drainage in Mohave County, Arizona

Abstract

Research Article| January 01, 1974 Peach Springs Tuff: Its Bearing on Structural Evolution of the Colorado Plateau and Development of Cenozoic Drainage in Mohave County, Arizona RICHARD A. YOUNG; RICHARD A. YOUNG 1Department of Geological Sciences, State University of New York, Geneseo, New York 14454 Search for other works by this author on: GSW Google Scholar WILLIAM J. BRENNAN WILLIAM J. BRENNAN 1Department of Geological Sciences, State University of New York, Geneseo, New York 14454 Search for other works by this author on: GSW Google Scholar GSA Bulletin (1974) 85 (1): 83–90. https://doi.org/10.1130/0016-7606(1974)85<83:PSTIBO>2.0.CO;2 Article history first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation RICHARD A. YOUNG, WILLIAM J. BRENNAN; Peach Springs Tuff: Its Bearing on Structural Evolution of the Colorado Plateau and Development of Cenozoic Drainage in Mohave County, Arizona. GSA Bulletin 1974;; 85 (1): 83–90. doi: https://doi.org/10.1130/0016-7606(1974)85<83:PSTIBO>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 Peach Springs Tuff, a welded ash flow of Miocene age, formerly blanketed a minimum area of 2,000 sq mi on both sides of the western edge of the Colorado Plateau in Mohave County, Arizona, and filled northeast-trending, pre–Colorado River canyons cut through the Paleozoic rocks.Paleomagnetic direction, petrography, and field relations indicate that the tuff is a single cooling unit of trachytic composition and normal polarity. It was erupted across the region prior to the last major movement of the plateau marginal faults, the completion of a significant amount of Basin and Range block faulting, and development of the existing topographic relief. A pre-tuff period of uplift and erosion exposed the Precambrian basement rocks directly west of the plateau.Gravel buried in canyons beneath the tuff on the edge of the Hualapai Plateau is evidence of northeast-flowing, incised drainage, in pre-tuff time, which probably continued northward along the Hurricane fault zone across the region where the younger canyon of the Colorado River is now. This ancient drainage system was disrupted by faulting, volcanism, and localized fluvial aggradation, followed by gradual incision of the modern Colorado River drainage.South of the Truxton Valley, there is evidence of a pre–middle Miocene drainage divide along the edge of the present plateau.All geologic evidence points to an early to middle Pliocene age for the modern Colorado River and associated tributary drainage on the Hualapai Plateau west of the Hurricane fault. 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.