Quaternary glaciation and volcanism, Metolius River area, Oregon

Research Article| January 01, 1977 Quaternary glaciation and volcanism, Metolius River area, Oregon WILLIAM E. SCOTT WILLIAM E. SCOTT 1Department of Geological Sciences, University of Washington, Seattle, Washington 98195 Search for other works by this author on: GSW Google Scholar Author and Article Information WILLIAM E. SCOTT 1Department of Geological Sciences, University of Washington, Seattle, Washington 98195 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1977) 88 (1): 113–124. https://doi.org/10.1130/0016-7606(1977)88<113:QGAVMR>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 Email Permissions Search Site Citation WILLIAM E. SCOTT; Quaternary glaciation and volcanism, Metolius River area, Oregon. GSA Bulletin 1977;; 88 (1): 113–124. doi: https://doi.org/10.1130/0016-7606(1977)88<113:QGAVMR>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 Evidence of three major Quaternary glaciations is recognized in the Metolius River area on the east flank of. the High Cascades. The latest glaciation (Cabot Creek glaciation) is multiple, with evidence of a late readvance (Canyon Creek advance) well displayed in cirques. Post-Altithermal glacial activity is restricted to a twofold late Neoglacial advance on Mount Jefferson and Three-Fingered Jack. Stone-weathering characteristics and soil development are used to differentiate and correlate the drifts throughout the area. The degree of soil development on the drifts suggests that there was a longer period of time between the oldest and intermediate glaciations than between the intermediate and youngest glaciations.Volcanic activity may have been restricted to times of little ice cover, since no evidence of intraglacial volcanism was observed. Tephra and lava flows were erupted during two Pleistocene interglaciations and during Holocene time at scattered locations. The High Cascade platform and probably the stratovolcanoes were largely constructed prior to the earliest recognized glaciation (Abbott Butte glaciation).Information on extent of ice cover during the Cabot Creek glaciation and the Neoglacial advance is sufficiently detailed to reconstruct past glacier margins and estimate former equilibrium-line altitudes (ELA). An accumulation-area ratio of 0.6 ± 0.1 was employed to calculate past ELAs. During the Cabot Creek glaciation, ELAs ranged from about 950 m lower than present at the maximum to 700 to 750 m lower than present for the Canyon Creek advance. Neoglacial ELAs on Mount Jefferson glaciers were lower than present by 200 to 250 m. ELA gradients across the Western Cascades during the Cabot Creek glaciation averaged about 5 m/km, increased to 14 m/km across the High Cascades, and were greater than 38 m/km farther east. This reflects a pattern of precipitation similar to that of the present. 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.