Mystery Quakes May Be Among World’s Longest-Lived Aftershocks
By Ilima Loomis 23 hours ago
Central Washington State isn’t known for being very seismically active, especially compared with the western part of the state, where earthquakes are fairly common. But the town of Entiat, about 3 hours east of Seattle, is an exception: The area recorded hundreds of earthquakes over the past century. A group of scientists investigating this unusual and long-lasting activity recently reported that the quakes may actually be aftershocks of a larger earthquake, one that occurred 145 years ago.
“I went into the study thinking, ‘you know, it’s been 145 years; they’re probably not aftershocks.’”
Tom Brocher, a research geophysicist at the U.S. Geological Survey’s Earthquake Science Center in Menlo Park, Calif., and lead author of the study published in the October issue of the Bulletin of the Seismological Society of America, said he was surprised by the results. “I went into the study thinking, ‘you know, it’s been 145 years; they’re probably not aftershocks,’” he said. “I had more of a regional interest in trying to figure out what’s causing these earthquakes in central Washington.”
https://eos.org/articles/mystery-quakes-may-be-among-worlds-longest-lived-aftershocks
