Skip to main content
U.S. flag

An official website of the United States government

Eruptive history of Middle Sister, Oregon Cascades-Product of a late Pleistocene eruptive episode

August 10, 2018

New mapping, geochemistry, and argon geochronology illuminate a brief, remarkably silicic episode set in a mafic segment of the Cascade arc. Middle Sister was constructed during a 35-k.y. episode in the late Pleistocene from mafic, intermediate, and silicic eruptions adjacent to the primarily rhyolitic South Sister. Eruptions in the Three Sisters volcanic cluster prior to 50 ka were exclusively mafic (

Publication Year 2018
Title Eruptive history of Middle Sister, Oregon Cascades-Product of a late Pleistocene eruptive episode
DOI 10.1130/GES01638.1
Authors Andrew T. Calvert, Judith E. Fierstein, Wes Hildreth
Publication Type Article
Publication Subtype Journal Article
Series Title Geosphere
Index ID 70262507
Record Source USGS Publications Warehouse
USGS Organization Volcano Science Center
Was this page helpful?