Record earthquake activity off the coast of Vancouver Island hints at the birth of new oceanic crust.
© Paul Biris via Getty ImagesVictoria Harbor on Vancouver Island, Canada sits near the Juan de Fuca Ridge, where researchers recently measured nearly 2,000 earthquakes in a single day.
Almost 2,000 earthquakes rocked a spot off the coast of Canada in a single day earlier this month, which could be a sign that new oceanic crust is about to be birthed via a deep sea magmatic rupture.The quakes aren't any threat to people. They're relatively small and centered on a spot called the Endeavour site, about 150 miles (240 kilometers) off the coast of Vancouver Island. This spot hosts a number of hydrothermal vents and sits on the Juan de Fuca Ridge, where the ocean floor is spreading apart. This area is separate from the
subduction zone — a region where one tectonic plate is sinking into the mantle underneath another plate — closer to the coast that can create large, destructive earthquakes, said
Zoe Krauss, a doctoral candidate in marine geophysics in the University of Washington.
"Mid-ocean ridges aren't actually capable of producing that large of earthquakes, not too far above a magnitude five," Krauss told Live Science. "This is not going to trigger 'the big one' on the subduction zone."
The quakes are interesting scientifically because they can reveal details about how the ocean floor pulls apart and new crust forms, Krauss said. At the Endeavour site, the Pacific plate and the Juan de Fuca plate are pulling apart. This stretching creates long, linear fault lines and thins the crust, enabling magma to rise up. When the magma reaches the surface, it cools and hardens, becoming new ocean crust.
Comment: Update March 25
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