Second strong quake jolts Alaska Peninsula within four days, aftershock threat persists

The Alaska Peninsula experienced yet another powerful earthquake early Monday morning, marking the second major seismic event in the region within just four days. According to the National Center for Seismology (NCS), the latest quake occurred at 3:58 AM IST on July 21, registering a magnitude of 6.2 on the Richter Scale. The tremor originated at a shallow depth of 48 kilometers, with its epicenter located at latitude 54.99°N and longitude 159.98°W.

In a statement released on X (formerly Twitter), the NCS emphasized that the quake’s shallow depth heightens the risk of aftershocks in the area. Experts caution that shallow earthquakes tend to cause more severe ground shaking compared to deeper ones, potentially resulting in greater damage and risk to life.

This seismic event comes just days after a more powerful earthquake measuring 7.3 struck the same region on July 17 at 2:07 AM IST. That quake, too, occurred at a shallow depth of 36 kilometers, with coordinates pinpointed at 54.91°N and 160.56°W.

The Alaska Peninsula lies along the Alaska-Aleutian subduction zone, one of the world’s most geologically volatile regions. It holds the record for generating the highest number of magnitude 8.0+ earthquakes globally in the past century. The area is also particularly vulnerable to tsunamis triggered by seismic activity or underwater landslides.

In addition to its seismic risks, the region is home to more than 130 volcanoes and volcanic fields—comprising over 75% of all volcanic eruptions in the United States during the past 200 years.

Authorities are maintaining heightened surveillance in light of the back-to-back quakes. Residents and nearby communities have been urged to stay alert for aftershocks and possible secondary hazards such as landslides or tsunami waves.