2 more small quakes in a half hour rattle area south of the Twin Sisters Monday afternoon
Two small earthquakes within a half hour of each other shook just south of the Twin Sisters and within 14 miles of the summit of Mount Baker Monday afternoon. It was the second quake to strike the area in the past 48 hours.
The first quake, which struck at 3:27 p.m. Aug. 23, initially was measured with a 3.5 magnitude, according to the U.S. Geological Survey’s web page on the quake, but was later downgraded to 2.8 magnitude. It struck approximately 25 miles east southeast of Bellingham and 6.5 miles north of Hamilton in Skagit County.
The epicenter was located just north of the South Fork of the Nooksack River and approximately six miles directly south of the South Twin, according to Google Maps.
The quake was measured near 2.4 kilometers beneath the earth’s surface, the USGS reported.
The second quake struck at 3:50 p.m. Monday and was measured at a 2.5 magnitude, according to the U.S. Geological Survey’s web page on the quake.
Its epicenter was approximately a mile and half southeast of the first, according to Google Maps, which the USGS reported was about 26 miles east southeast of Bellingham and 5.6 miles north northeast of Hamilton. Its depth was 2.8 kilometers beneath the earth’s surface, according to the USGS.
As of Tuesday morning, 34 people, including six in Whatcom County had reported feeling the shaking of the first quake on the USGS’ “Did You Feel It?” page. Eight people reported feeling the second quake, though only one was in Whatcom County.
Quakes of less than magnitude 3.0 are common, and tens of thousands are reported worldwide every year, according to the USGS. A quake of magnitude 1.0 to 3.0 is not felt except by a very few under especially favorable conditions, according to the USGS.
The quakes were within several miles of where a 2.3-magnitude quake struck Saturday evening.
This story was originally published August 23, 2021 at 4:09 PM.
