Did you feel that earthquake Monday morning?

Monday morning’s quake was about 30 miles southwest of Bellingham.
Monday morning’s quake was about 30 miles southwest of Bellingham. Courtesy to The Bellingham Herald

A small earthquake shook the San Juan Islands on Monday morning, one of a dozen tiny shakers within a few miles of each other, starting Sunday night and lasting into Monday afternoon.

A quake of magnitude 3.1 was reported at 3:03 a.m. Monday, centered in the Salish Sea about one-half mile between the northern tip of San Juan Island and the southwestern tip of Orcas Island – about 30 miles southeast of Bellingham. It was measured at 8.5 miles deep, according to the Pacific Northwest Seismic Network.

Recordings at the U.S. Geological Survey placed the quake at 5 1/2 miles north-northwest of Friday Harbor, on San Juan Island.

It’s nothing to be alarmed about. But it woke them up in the San Juans.

John Vidale, seismologist

A quake of magnitude 3.0 is easily felt by humans, but rarely causes damage, the USGS said.

No damage was reported, but it awakened at least 120 residents of the San Juan Islands who reported the quake on the USGS’ “Did You Feel It?” web page.

“People shouldn’t worry, but it is somewhat unusual,” said seismologist John Vidale, director of the Pacific Northwest Seismic Network and University of Washington professor. “It’s nothing to be alarmed about. It was up in the crust. But it woke them up in the San Juans.”

Nine smaller quakes hit the immediate area within the last day: a 2.8 magnitude quake at 6:28 p.m. Sunday, followed by a 1.4 magnitude quake at 12:10 a.m. Monday and seven other quakes from 2:47 a.m. to 5:47 a.m. Monday, ranging in magnitude from .03 to 1.7.

Two additional quakes were recorded in the same general region almost simultaneously at 2:42 p.m. Monday. They were magnitude 1.5 and 1.6.

Quakes of less than magnitude 3.0 are common, and tens of thousands are reported worldwide every year, according to the USGS.

Robert Mittendorf: 360-756-2805, @BhamMitty

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