Stratigraphic, sedimentologic, and petrologic record of late Miocene subsidence of the central Oregon High Cascades

Abstract

Research Article| May 01, 1987 Stratigraphic, sedimentologic, and petrologic record of late Miocene subsidence of the central Oregon High Cascades Gary A. Smith; Gary A. Smith 1Department of Geology, Oregon State University, Corvallis, Oregon 97331 Search for other works by this author on: GSW Google Scholar Lawrence W. Snee; Lawrence W. Snee 1Department of Geology, Oregon State University, Corvallis, Oregon 97331 Search for other works by this author on: GSW Google Scholar Edward M. Taylor Edward M. Taylor 1Department of Geology, Oregon State University, Corvallis, Oregon 97331 Search for other works by this author on: GSW Google Scholar Author and Article Information Gary A. Smith 1Department of Geology, Oregon State University, Corvallis, Oregon 97331 Lawrence W. Snee 1Department of Geology, Oregon State University, Corvallis, Oregon 97331 Edward M. Taylor 1Department of Geology, Oregon State University, Corvallis, Oregon 97331 Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1987) 15 (5): 389–392. https://doi.org/10.1130/0091-7613(1987)15<389:SSAPRO>2.0.CO;2 Article history First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Gary A. Smith, Lawrence W. Snee, Edward M. Taylor; Stratigraphic, sedimentologic, and petrologic record of late Miocene subsidence of the central Oregon High Cascades. Geology 1987;; 15 (5): 389–392. doi: https://doi.org/10.1130/0091-7613(1987)15<389:SSAPRO>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 Pliocene to Holocene volcanics of the central Oregon High Cascades, largely confined to an intra-arc graben, bury older volcanic centers. Early High Cascade volcanism is recorded by late Miocene volcanics and sediments of the Deschutes Formation that accumulated in a fluvial basin east of the Cascades. Aggradation in the adjacent fluvial basin occurred episodically when pyroclastic debris choked streams. Deschutes basin aggradation commenced near 7.4 Ma and was synchronous with extension-influenced Cascade magmatism dominated by basalts and basaltic andesites. Initial subsidence of the Cascades occurred at about 5.4 Ma in response to plate-margin processes. Structural isolation of the basin from ignimbrites and volcanism-induced sedimentation resulted in widespread development of superimposed paleosols in the basin. Subsequent mafic lavas erupted near the eastern margin of the initial depression were truncated by east-stepping, down-to-the-west faults at about 5.3 Ma. 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.