ALEUTIANS WEST CENSUS AREA, AK — A 6.3 magnitude quake slammed near Nikolski at midnight on Thursday, the U.S. Geological Survey reported.

A tremor rocked the area at 11:17 a.m. (12:17 a.m. local time). The earthquake’s epicenter was about 52 miles south-southwest of Nikolski and occurred at a depth of 22 miles. Seismologists first reported it as a 6.2 event, but later upgraded it to 6.3.

Did you feel it?

You can let the USGS know if you noticed the quake by filling out their Felt Report form.

Impact and estimated losses

The USGS categorized this as a Green Alert, which means there is a low likelihood of casualties and damage.

Structure information summary

Most structures in this region are resistant to earthquake shaking, though vulnerable structures exist. The predominant vulnerable building types are unreinforced brick masonry and reinforced masonry construction.

Earthquakes past week

Last week, there have been 52 tremors of magnitude 2.5 or greater centered nearby. The strongest, a 5.3 magnitude quake, was recorded in the same region on Sep. 31.

Area struck by 6.9 quake in 1987
The area has weathered major earthquakes before. On Feb. 27, 1987, a magnitude 6.9 tremor struck southwest of Unalaska in Aleutians West Census Area, at a depth of 6.2 miles.

Source: The U.S. Geological Survey