2018 M7.9 Offshore Kodiak Earthquake

The source complexity of the M7.9 Offshore Kodiak Earthquake is demonstrated by the aftershock distribution, which extends over a 100 km x 100 km (62 miles x 62 miles) region. The largest aftershock was a M5.6 that occurred more than three months into the sequence. More than 270 aftershocks with magnitudes greater than 4 were recorded. The Alaska Earthquake Center reported nearly 5,000 aftershocks through the end of 2019. The magnitude of completeness for this sequence is around 3 due to the lack of station coverage within 150 miles of the sequence. Aftershocks are likely to continue for a few years.

Last Modified: April 15, 2024