ellowstone Hot Spot Shreds Ancient Pacific Ocean

[n2doc]

Analysis by Michael Reilly

If you thought the geysers and overblown threat of a supervolcanic eruption in Yellowstone National Park were dramatic, you ain't seen nothing: deep beneath Earth's surface, the hot spot that feeds the park has torn an entire tectonic plate in half.

The revelation comes from a new study in the journal Geophysical Research Letters that peered into the mantle beneath the Pacific Northwest to see what happens when ancient ocean crust from the Pacific Ocean runs headlong into a churning plume of ultra-hot mantle material.

Geologically speaking, the Pacific Northwest is a peculiar place. Hot spots usually sit way out on their own in the middle of a tectonic plate (think Hawaii or the Galapagos). Not Yellowstone -- it pokes its way to the surface just a few hundred miles from the edge of the North America plate, where a giant trench sends the Juan de Fuca tectonic plate sliding underneath Washington, Oregon, and northern California.

So, who cares? The encounter has had several amazing consequences. First, and most obvious, it resurfaced much of northern Nevada, Idaho, and Wyoming over the last several million years in basalt through a series of massive volcanic eruptions. Then there were the tremendous supervolcanic explosions, which coated much of the western U.S. in thick blankets of ash and made the Yellowstone park region what it is today.


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http://news.discovery.com/earth/yellowstone-hot-spot-shreds-ancient-pacific-ocean.html

[AlecBGreen]

1. interesting read but have a bone to pick w the author

"Hot spots usually sit way out on their own in the middle of a tectonic plate (think Hawaii or the Galapagos)..."



I count 25 hotspots, many of which (10+, including the Galapagos) are directly on plate boundaries. 2 more (east african rift zone) are under a newly forming boundary, and 2 more (near madagascar) are likely going to create the rest of that divergent boundary by linking up with the indian plate boundary. So no, "hotspots DONT usually sit way out on their own in the middle of a tectonic plate."

"Not Yellowstone -- it pokes its way to the surface just a few hundred miles from the edge of the North America plate..."

By that metric, almost every single hotspot is 'next to' a boundary.

If someone is going to write a SCIENTIFIC article for a SCIENTIFIC magazine (for a living, no less!) they should try to get their facts straight. Sorry for my McCain grouchy-old-man impersonation ;)

[Odin2005]

2. Very interesting!