An unfelt seismic event is taking place beneath western Washington. Earlier in the week, seismographs in the southern Hood Canal area began recording bursts of low-level shaking associated with what is called an episodic tremor-and-slip event. If this episode behaves true to form, the tremor will move north beneath the Olympic Mountains and across to Vancouver Island during the next two to three weeks. This the fifth so-called slow-slip event to be recorded since the phenomenon was discovered in 2002. Slow-slip events, or silent earthquakes, occur at a depth of about 25 miles and can last for several weeks. Though they are unfelt by humans, they can release as much energy as a large earthquake. Since they were first discovered in the Puget Sound region, such events have occurred regularly about every 14 months. The current slow-slip event was expected to start between mid-February and mid-April, and the first evidence that it had begun turned up on Sunday.
Nature has a way of continually surprising us and inspiring awe within us, and it seems there are just as many fantastical wonders t...