3 small quakes reported near Santa Rosa

A 2.3 magnitude temblor was recorded at 8:04 p.m. Saturday, followed by two other “micro” quakes early Sunday just east of Santa Rosa.|

PRESS DEMOCRAT STAFF

October 1, 2022

How to prepare for an earthquake

One of the most important things you and your family can do before an earthquake is to have a plan:

— Be prepared by creating a plan for how to reach one another.

— Establish out-of-area contact who coordinate family members' locations and information should you become separated. Make sure children learn the phone numbers and addresses, and know the emergency plans.

— Keep copies of important documents at the house of your out-of-area contact or keep important documents and valuables in a fireproof storage box or safe deposit box.

— Prepare a disaster supplies kit, which includes emergency food and water for the home. Keep a smaller version in your vehicle. Families with children should have each child create their own personal pack. View the California Department of Public Health's recommendations on what to pack.

— Know evacuation routes. Establish several different routes in case certain roads are blocked or closed.

— Decide how to take care of pets. Pets are not allowed in places where food is served — so you will need to have a place to take your pets if you have to go to a shelter.

— Don't run out of gas! Always run on the top half of the tank, not on the bottom half.

— Visit other earthquake preparation sites, including: Earthquake Country Alliance, SF72, Great California Shakeout, and Santa Rosa Citizens Organized to Prepare for Emergencies (COPE).

Source: srcity.org

Three very small temblors were recorded this weekend in Sonoma County, earthquake experts reported.

The first one occurred just after 8 p.m. Saturday, roughly 2 miles east of Santa Rosa.

According to initial readings, it occurred at 8:04 p.m. and registered 2.4 magnitude. It was later downgraded to 2.3.

The Southern California Earthquake Data Center classified the temblor as a “micro” quake and estimated its depth at about 5.6 miles below the earth’s surface.

Just after 4 a.m. Sunday two additional micro quakes were reported.

The first, a 1.4 magnitude, was recorded at 4:09 a.m. and originated 8 miles slightly northeast of Cloverdale, according to the data center. Its depth was 1.5 miles.

The second micro temblor, which occurred at 4:25 a.m., registered 1.6 magnitude with a depth of well under a tenth of a mile. It was about half a mile southeast of the Larkfield-Wikiup area, just north of Santa Rosa.

There were no reports of any injuries or damage in any of the events.

The U.S. Geologic Survey, which usually lists only quakes of 2.5 magnitude or greater, did have mentions of the three temblors.

According to an earthquake magnitude scale published by Michigan Tech University, a 2.5 temblor will barely be felt and will likely cause no damage.

These three minor events come on the heels of two larger quakes that occurred Sept. 13 along the Rodgers Creek fault.

The 4.4 and 4.3 magnitude shakers occurred 42 seconds apart at about 6:39 p.m. and caused moderate damage to a number of homes in the Larkfield-Wikiup area.

The Rodgers Creek fault, runs from San Pablo Bay at the southern tip of Sonoma County north through Santa Rosa to Healdsburg. It is also part of the Hayward fault system.

It sits along Santa Rosa's east side — from Taylor Mountain, through Doyle Park, near Providence Santa Rosa Memorial Hospital and past the Santa Rosa Rural Cemetery.

The last big earthquake along it occurred 53 years ago.

Scientists say the Hayward-Rodgers Creek fault line is most likely to produce a major earthquake in the region in the coming years.

They forecast about a 33% chance of at least one magnitude 6.7 quake or greater occurring somewhere on one of the faults, or simultaneously, by 2043.

The seismic activity Sept. 13 apparently shook loose a water source beneath Mark West Creek, boosting the drought-depleted stream level by about 6 inches in the hours following the temblor and bumping the current flow to more than seven times its previous rate.