Pacific Northwest Volcanism—55 million years to present

Collaboration between Oregon State University and IRIS

The Pacific Northwest is a volcanological wonderland. The western margin of North America has long been dominated by subduction and dextral transtension. Ocean-ridge rifting produces submarine volcanism offshore. Subduction of the young Juan de Fuca Plate creates the arc of Cascades volcanoes. Hot-spot volcanism drives the Yellowstone caldera system. Continental extension of the Basin and Range province, plus a northward migrating triple junction add to a complex volcanic history.

Using map view in concert with cross sections, this animation steps the viewer through both volcanic and simplified tetonic processes. 

CLOSED CAPTIONING: .srt file is included with the download. Use an appropriate media player to utilize captioning.


Keypoints:

Tectonics of the Pacific Northest yield:

  • Active ocean-ridge volcanoes
  • Cascades Arc of subduction related volcanism
  • Back-arc volcanoes
  • Yellowstone Hotspot
  • Basin and Range lava fields


Level: Intermediate

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