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Geology

Geology Faculty Publications and Presentations

2022

Volcanic ash tuff etc -- Eastern Oregon

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Full-Text Articles in Physical Sciences and Mathematics

Filling Critical Gaps In The Space-Time Record Of High Lava Plains And Co-Columbia River Basalt Group Rhyolite Volcanism, Vanessa Marie Swenton, Martin J. Streck, Daniel P. Miggins, William C. Mcintosh Nov 2022

Filling Critical Gaps In The Space-Time Record Of High Lava Plains And Co-Columbia River Basalt Group Rhyolite Volcanism, Vanessa Marie Swenton, Martin J. Streck, Daniel P. Miggins, William C. Mcintosh

Geology Faculty Publications and Presentations

Miocene rhyolitic volcanism of eastern Oregon, USA, can be divided into two main episodes. Mantle plume upwelling is thought to have generated Columbia River Basalt Group (CRBG) lavas and coeval >16.5−15 Ma silicic volcanism trending north−south from northeast Oregon to northern Nevada. Rhyolite volcanism of the 12−0 Ma High Lava Plains province has been ascribed to either buoyancy-driven westward plume spreading or to slab rollback and mantle convection spanning from southeast Oregon to Newberry Volcano to the west. The apparent ca. 15−12 Ma eruptive hiatus suggests that rhyolites of these provinces were a product of separate processes, yet this gap …


Pre-Eruptive Magma Configurations And Petrogenetic Relationships Of The Rattlesnake Tuff, Oregon–Insights From Spectacularly Banded High-Silica Rhyolite Pumices, Vanessa M. Swenton, Martin J. Streck May 2022

Pre-Eruptive Magma Configurations And Petrogenetic Relationships Of The Rattlesnake Tuff, Oregon–Insights From Spectacularly Banded High-Silica Rhyolite Pumices, Vanessa M. Swenton, Martin J. Streck

Geology Faculty Publications and Presentations

The 7.1Ma Rattlesnake Tuff (RST) of eastern Oregon is a widespread and voluminous (>300 km3) ignimbrite composed of 99% crystal poor (≤1%) high-silica rhyolite (HSR) and