March 18, 2011

NNW Jerome, AZ


A earthquake of Magnitude 3.7 shook the region north of Jerome, AZ this afternoon a little before 1:00 pm. As of 1.30 this afternoon we have received 2 felt reports from the Cottonwood area, about 10 km to the SE of the epicenter. This earthquake is the latest in a series of smaller events in the area starting with the magnitude 3.6 west of Sedona, Arizona in January this year.

We currently have no fault plane solutions for this event. The nearest faults are the Big Chino 30 km to the northwest, the Little Chino, mapped late in 2009 by the AZGS, and the Prescott and Williamson Valley Grabens. The Prescott Valley fault is thought to be responsible for the February 1976 Magnitude 4.9. event. The latest activity on the Big Chino was between 1994 and 1997- the largest event being 3.6. This fault is estimated to be capable of generating 6.5-7.0 magnitude events at a recurrence of 10,000 to 30,000 years. In general these are N-NW trending normal faults.

The data for this afternoon's earthquake are as follows: