RIDGECREST – (INT) – The earth is still moving in a 3-county area, but most aftershocks in the so-called Ridgecrest Sequence that began more than a month ago are no longer perceptible.

Of the tens of thousands, the strongest are barely above M3.0.

Aftershocks are occurring over a 31 mile wide area, with a cluster of activity approximately 15 miles NW from the mainshock and about 6 miles to the southeast of the Coso Geothermal Field.

The initial M6.4 and M7.1 quakes were the result of shallow strike slip faulting in the crust of the North America plate, the USGS said. They were the strongest in Southern California in 20-years.

Aftershocks are expected to continue for months to years, but the magnitude and number will decrease through time, the USGS predicted.

Story Date: August 19, 2019