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Volcanoes & Earthquakes


Earthquake Activity

Yellowstone Super Volcano

"The Plume"

-- For years, scientific reasoning had postulated a finger, (plume,) of very hot and molten rock extending through the earth's mantle causing volcanic disturbances at the surface of the earth.

-- Sound hypotheses and reasoned speculation suggested that the plume was responsible for the surface geology and topography from near the Oregon-Idaho-Nevada border to Yellowstone.

-- New data, some new techniques of research, plus the integration of the old data now let us "see" the plume in 3-D. It extends down and to the west and north for quite some distance.

Image From: Science Daily; courtesy University of Utah.

The 17 million year earth forming saga has created much of the topography of Northern Nevada, Southern Idaho, Southwestern Montana - and perhaps much of the Columbia River basin in Eastern Washington and Oregon.

Known colloquially as the "Yellowstone Hotspot" this volcanic plume has bubbled throughout it's life and caused several eruptions along the way.

In the recently published special volume of the Journal of Volcanology, a team of researchers has detailed our current knowledge of this plume that created the park next door to West Yellowstone - AND, influenced it's weather.

The new findings, based on recent developments of seismic imaging, are fascinating. The plume extends to a depth of at least 450 miles with "blobs" at depths of about 355, 310, and 255 miles. Between 8% & 15% of the plume is melt, (liquid of a very viscous sort.) That's a very high percentage and makes the plume very restless.

The plume is being deformed, (or 'blown ',) by the earth's mantle, which is moving at about 2-inches-per-year in a southwest direction. No wonder we have about 300 earthquakes per year - or more! MY MY.