This is a past event.

Anita Grunder
Oregon State University
Corvallis, OR

The abundant late Cenozoic bimodal volcanism of the Pacific Northwest occupies an enigmatic intracontinental tectonic setting affected by Cascadia subduction, Basin and Range extension, the Yellowstone plume, and lithospheric topography at the edge of the North American craton. The High Lava Plains of Oregon are characterized by thin widespread Miocene-Pleistocene lava flows of primitive basalt and a belt of silicic eruptive centers that are successively younger to the northwest, describing a mirror image to the basalt plateau and rhyolite age progression of the Snake River Plain. The High Lava Plains are associated with a zone of numerous, small northwest-striking faults and lies at the northern limit of major Basin and Range normal faults. The purpose of the talk is to focus on the late Cenozoic lithospheric evolution of this region, through the lens of the High Lava Plains, by considering structural, geophysical, and temporal perspectives with an emphasis on the petrologic evolution.

Suggested Reading Material

High Lava Plains website: http://www.dtm.ciw.edu/research/HLP/

JORDAN, GRUNDER, DUNCAN, DEINO
Geochronology of age-progressive volcanism of the Oregon High Lava Plains: Implications for the plume interpretation of Yellowstone

Host Elisabet Head (emhead@mtu.edu)