A dying tectonic plate is creating a gaping hole beneath the ocean waters off the West Coast of the United States. It may seem as if it's wreaking havoc on the surface of the Earth, but it is not what people would expect.
The movement could trigger other earthquakes off the coast of Northern California, but it could also be used to explain why new volcanoes are being discovered in central Oregon. A new study found that the dying tectonic plate may have a tear. They may not be the first group to speak of it, but with a more detailed data set, they are the first one to say with most certainty that the dying is happening.
"Several studies have debated whether there was a tear or that there is none, but now, we are certain that the tear is real," said William Hawley, lead researcher and a doctoral student in the Earth and Planetary Science Department from the University of California, Berkeley. He told Live Science of their findings with utmost certainty.
The Juan de Fuca (pronounced as "whan de fyoo-kuh") stretches about 1,000 kilometers along the Pacific Northwest coast, from Vancouver Island, Canada, to Cape Mendocino, California. "There is no part of this plate that is found above water. It is basically a total of oceanic plate," Hawley said.
Between the period of 2011 to 2015, scientists studied different parts of the Juan de Fuca plate. They dropped seismometer ocean-bottom and let the sensors to collect seismic data from earthquakes that happen all over the world in a span of a year. After a year, the researchers went back to fish up the seismometers and upload all the data it has collected. This has allowed them to create a layout of the plate. Then, the researchers decided to deploy the devices in another location where the plate runs.
The data collected from the seismometers showed that seismic waves have travelled through the plate, which in turn, has revealed useful information about the plate including its composition and varying temperatures. There was one region where the plate runs under the central Oregon gap with high intensity seismic waves. Harley then interpreted it to be the hole. Along with his co-author in the study Richard Allen, Hawley hypothesized that the weak zone in the Juan de Fuca exists because there exists two ridges with overlapping segments.
"This tearing may eventually cause the plate to become fragments and the small parts of the plate will attach to the other plates nearby," the researchers wrote in their study. Simply put, "we seem to be witnessing the death of a plate, but it will take a few years for a plate to die," Hawley said.
The researchers estimate that the hole is located at a depth of 100km.
