Track a Major Earthquake and Its Aftershocks
When a big quake hits the news, use the tracker to follow the aftershock sequence in near real time.
- 1
Find the region of the mainshock
Open the region page where the large quake occurred. The mainshock will usually sit at the top of the strongest-sorted list, with its magnitude badge colored red or dark red.
- 2
Sort by newest to watch the sequence
Switch the sort to newest and refresh every few minutes. You will see smaller quakes appearing near the mainshock as faults around the rupture adjust. This is the aftershock sequence unfolding live.
- 3
Watch the rate slow down
Over the following days the aftershocks thin out, following Omori's law where frequency drops roughly with time. A region that was producing several quakes an hour may settle to a few a day within a week.