South Coast Geophysicist Says Tectonic Plate Off Pacific Northwest Poses Risk Of Mega-Earthquake

Jun 13, 2017

It’s a little known tectonic plate in the Pacific Ocean some 300 miles off the Pacific Northwest.

But, a UC Santa Barbara researcher says we need to learn more about it because it has the potential to trigger mega-earthquakes, and tsunamis.

Zach Eilon is a UCSB geophysicist who’s been studying the Juan de Fuca tectonic plate off the Pacific Northwest, which is sandwiched between the Pacific and North American tectonic plates a mile and a half below the ocean’s surface.

To visualize tectonic plates, think of the Earth like a hard boiled egg, with cracks in its shell. Now, if the pieces of the shell move against each other, some go under other pieces, some over, and some up against each other. In terms of the Earth, that kind of action can create mountains, ocean trenches, and earthquakes.

Eilon says they deployed some 70 seismometers underwater around the Juan de Fuca plate, so they could try to learn more about it. He says it allowed some of the most comprehensive research ever done on the plate and its boundaries. Eilon says they discovered the Pacific side of the plate had hot, molten material.

He says the research has provided important new information about the way the plates interact with each other. And, Eilon says the research also helps show that this is something which poses a major potential geologic hazard, potentially capable of a magnitude nine earthquake.

The UCSB researcher says he’s going to use some of what he learned monitoring the Juan de Fuca plate off the Pacific Northwest as part of an international effort to study a previously seismically uncharted part of the Pacific Ocean.

The Juan de Fuca plate research was published in the journal “Science Advances.”