Posted on 09/03/2018 10:26:25 PM PDT by BenLurkin
... Mount St. Helens is located outside the main line of the Cascade Arc of volcanoes.
...scientists discovered a giant subsurface rock formation, known as the Spirit Lake batholith. They say it appears the batholith diverted magma and partially melted rock outside of the arc and to the west, forming Mount St. Helens.
Researchers used two methods to analyze the subsurface rocks and geomagnetic and geoelectric fields; they studied data from earthquakes and explosions and used magnetotelluric to measure the Earth’s subsurface and conductivity.
,,,
Schultz said the batholith acts like a plug in the crust and diverted magma that would otherwise have erupted in line with the other major Cascade volcanoes. That’s how St. Helens formed to the west of the Cascadia Arc. This is also what caused Mt. Adams to form slightly to the east.
(Excerpt) Read more at katu.com ...
always wondered about this. Thanks for posting.
Ping
Way to the west of Rainier, Adams, Hood, Jefferson, etc.
It really is 2018.
Not my fault.
It’s name is for a woman and a woman never walks a straight line in Nature. She’s a free spirit and roams at will.
Weird that they named a volcano chain after dishwashing soap. ;^)
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