Earthquake rocked Northern California near Isleton. Did Stanislaus County feel it?
The United State Geological Survey sent a ShakeAlert on Wednesday morning warning some California residents that an earthquake was detected 2.5 miles south-southwest of Isleton, a 60-mile drive from Modesto, in Sacramento County.
The quake on Brannan Island was recorded as a 4.2 magnitude and described as having moderate shaking with a low likelihood of casualties and damage. It originated over 6.5 miles deep in the earth.
Nearly a month ago, Stanislaus County recorded at least six earthquakes in a 24-hour period.
Here’s where the fault lines are in Stanislaus County and how likely it is to have an earthquake in the region:
Editor’s note: The following information was originally published in a story on Sept. 19, 2023, and has been updated to reflect the most recent quake:
What parts of Stanislaus County can feel earthquakes the most?
Modesto would have felt weak shaking from the Isleton-area earthquake Wednesday morning, according to a USGS map.
Several faults run through Stanislaus County, including the Great Valley thrust fault system. The series of lines runs along the west side of the San Joaquin Valley, Belle Philibosian, a research geologist with the United States Geological Survey, previously told The Bee.
No active faults are currently known to exist within the valley portion of the county, a 2017 version of the county’s hazard mitigation plan says.
Since the 1970s, when there were instruments to record them in Stanislaus County, there have been dozens of earthquakes around 3-4.5 magnitudes, Philibosian said.
The active faults that may cause ground shaking in the county include the San Andreas, Calaveras and Hayward faults, according to Stanislaus County.
Earthquakes typically occur in the the western region of Stanislaus County. The effects of quakes that occur in that region lessen in the more incorporated parts of the county, like Modesto.
There is an 80.62% chance of a major earthquake within 31 miles of Stanislaus County within the next 50 years, according to the 2017 hazard plan, and the probability of one impacting the region is likely.
What do you want to know about life in Modesto? Ask our service journalism team your top-of-mind questions in the module below or email servicejournalists@modbee.com.
