The largest earthquakes this evening - one with a magnitude of 3.7 and the other with a magnitude of 3.9 - shook an area seven miles west of Prunedale at 7:54 p.m. and 8 p.m., respectively.
Since Wednesday morning, that area of the hills bordering Monterey and San Benito counties has experienced 27 earthquakes following the magnitude 4.5 quake that punctuated the day's seismic activity.
That tremor struck near Fremont Peak State Park at 12:51 a.m., according to the USGS, and had a depth of 1.8 miles. The epicenter was located 10 miles east-southeast of Prunedale and 45 miles south-southeast of San Jose.
Most of the aftershocks had a magnitude between 1.1 and 2.9, but four of the 27 measured 3.0 or larger.
Hundreds of people in the Bay Area reported that they felt weak shaking due to the quakes, according to information collected by the USGS, with the strongest shaking felt around Salinas and San Juan Bautista and weak shaking reported as far away as San Rafael.
This is the second time since Friday that the greater Bay Area has experienced a temblor with a magnitude larger than 4.0. On Friday, an earthquake with a magnitude of 4.1 struck east of San Jose and could be felt throughout much of the Bay Area.
Before Wednesday, the most recent earthquake in the San Juan Bautista area measured 2.2 and struck on Jan. 6, 2011, according to the USGS.