30 Cenozoic dynamics of the western North American plate boundary: Insights from offshore marine geology and geophysics into Cordilleran tectonics
We invite presentations on Cenozoic tectonics, volcanism, sedimentation, and geohazards offshore and along the margin of western North America. Example topics include crustal structure, mantle processes, triple-junction migration, paleomagnetism, active faulting, marine stratigraphy, and seismicity.
Friday, 24 April 2026
8:00 AM - 12:00 PM
LMH, Deli
The Yellowstone Hot Spot or Not Revisited
Paper number: 30-7
Program: Technical Sessions
Time: 9:55 AM – 10:15 AM
Authors
Abstract
Reviewed here is a brief history of the Yellowstone Hotspot concept, the early seismic imagery not showing a deep mantle source and more recent imagery showing a possible deep mantle source. The deep mantle plume is evaluated in the broader context of the tectonic histories of the Western US, the East Pacific Rise spreading ridge, and the Farallon Oceanic Plate subducted under North America using Paleomap Paleoatlas v1f (ESHGIS) software. It is concluded that the Plume imaged from the deep mantle does not appear to engage the McDermott Caldera or the time transgressive path from there to Yellowstone considered to be the diagnostic hot spot signature. Alternate explanation will be required for both the northeastward toward Yellowstone and the northwestward toward Newberry volcanic trends from McDermott. A further conclusion is that relict activity from the subducted East Pacific Rise should not be ignored in interpreting the vast shallow fast anomaly south of the Mendocino Fracture Zone in North America.
Geological Society of America Abstracts with Programs. Vol. 58, No. 3
doi: 10.1130/abs/2026CD-410743
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