Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 1 of 1
Full-Text Articles in Physical Sciences and Mathematics
A Petrologic Study Of The Teanaway Basalt: Eocene Slab Window Volcanism In Central Wa, Liz Roepke
A Petrologic Study Of The Teanaway Basalt: Eocene Slab Window Volcanism In Central Wa, Liz Roepke
Summer Research
The Teanaway Basalt (TB) includes subaerial basalt to andesite flows, mafic to felsic tuffs, and rhyolite domes in the Central Cascades of Washington State. These volcanics overlie the extensive ~47 Ma Teanaway Dike Swarm (TDS) that cuts the underlying Swauk Formation. Samples were collected from 3 main localities: Easton Ridge (ER) in the west, Liberty Ridge (LR) in the east, and the Middle Fork of the Teanaway River (MF) in the center.
The bimodal TB consists predominantly of basaltic andesite and andesite (45.3–63.1 wt% SiO2) with subordinate rhyolite (75.9–79.4 wt% SiO2). The mafic rocks classify as …