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Local politics, the county, and the world, as viewed by Tammy Maygra Tammy’s views are her own, and do not necessarily reflect the views of Bill Eagle, his pastor, Tammy’s neighbors, Wayne Mayo, Brian Stout, Former President Trump, Henry Heimuller, Joe Biden, Jerry Falwell Jr., Mike Johnson, Ted Cruz, Joe Biden’s dogs, or Claudia Eagle’s Cats. This Tammy’s Take (with the exception of this disclaimer) is not paid for or written by, or even reviewed by anyone but Tammy and she refuses to be bullied by anyone. See Bill’s Standard Disclaimer
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Under this beautiful area, the sea floor is moving and shaking Earthquakes as many as 2,000 a day.
Crustal Plate Techtonics
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. So far no threats to the people. They're relatively small and centered on a spot called the Endeavour site, about 150 miles 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. Mid-ocean ridges aren't actually capable of producing that large of earthquakes, not too far above a magnitude five. Scientists say 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. 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. On March 6, activity went wild, with at least 200 small earthquakes shaking the seafloor per hour. In all, the researchers detected about 1,850 quakes in a single day. The quakes are small pops but allows scientists to see what is moving and breaking. The most likely reason for the quakes is that the seafloor is stretched to its maximum extent and has built up a great deal of stress. At the Endeavour site, this happens when the plates pull apart by about 3.3 feet, and the stress is ultimately relieved when magma rises up into the thinned crust and cools. What is really cool is that this happens on an approximately 20-year cycle, which puts the area right on schedule: The last time it was this seismically shaky was in 2005. As of now the quakes have slowed down a lot, but teams of scientists are watching and learning from this event. With even better technology than 2005 had, scientists are learning a great deal about the earths crusts and earthquakes and faults.
Tammy
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