M3.3 Earthquake & aftershocks in northwestern-most Arizona

M3.3 Earthquake & 7 aftershocks (8/28/2017)

At 7:03 a.m. on 28 August, a magnitude 3.3 earthquake occurred in the northwest corner of Arizona about 20 miles SSE of Mesquite, Nevada. Seven smaller aftershocks followed on the heels of the initial event (Table 1, Figure 1). 

According to AZGS geologist Jeri Young, the earthquakes occurred just west of the Grand Wash Fault.  The range of depths, from 0 to 13 km is not uncommon ‘due to the westward stepping off the Colorado Plateau here.’

Table 1*. Earthquake events of NW Arizona of 8/28/2017 

MAGNITUDE (ML)            DATE               LAT        LONG       DEPTH (km)

0.8                        8/28/2017           36.593   -113.848              9.7

1.1                        8/28/2017           36.584   -113.866              13.3

1                            8/28/2017           36.609   -113.813              13.2

0.3                        8/28/2017           36.638   -113.832              12.1

0.2                        8/28/2017           36.611   -113.854              0

1.3                        8/28/2017           36.627   -113.823              12.3

1.2                        8/28/2017           36.622   -113.826              6.1

3.3                        8/28/2017           36.572   -113.887              3.8

*Data derived from the Arizona Broadband Seismic Network by Jeri Young (AZGS).