Explore clusters of M4.5+ events observed around significant earthquakes. These clusters are descriptive and are not presented as earthquake predictions.
After the M 7.8 reference event, Quake Pulse counts 10 M4+ event(s) in the first 24 hours and 22 in the first 7 days. Fourteen-day M4.5+ activity is about 34.8× the average equivalent derived from the previous year. The largest secondary event is M 1.7 below the reference event.
Descriptive comparison with M4.5+ events observed in the same radius during the 365 days before the sequence.
A ratio above 1 means denser M4.5+ activity than the average equivalent derived from the previous 365 days. It is not a risk measure or a forecast.
Earlier events are shown as context only. They are not labelled precursors and should not be interpreted as predictive signals.
Shows M4+ cluster events according to elapsed time after the reference event.
Dots represent M4+ events retained by the sequence detector. Dot size depends on magnitude.
Sequences are descriptive groupings based on spatial and temporal proximity. Quake Pulse does not establish a causal link between every event here and does not provide earthquake forecasts.
195 Felt reports · PAGER GREEN · Tsunami indicator · Shallow
| Magnitude | Location | Depth | Time | |
|---|---|---|---|---|
| M 7.8 | 2020 Perryville, Alaska Earthquake | 28.0 km | 2020-07-22 06:12:44 UTC | View event → |
| M 6.1 | 101 km ESE of Sand Point, Alaska | 16.5 km | 2020-07-22 06:16:18 UTC | View event → |
| M 5.6 | 122 km ESE of Sand Point, Alaska | 24.6 km | 2020-07-22 06:20:07 UTC | View event → |
| M 4.5 | 126 km SSE of Perryville, Alaska | 25.9 km | 2020-07-22 06:22:15 UTC | View event → |
| M 5.7 | 76 km ESE of Sand Point, Alaska | 45.2 km | 2020-07-22 08:13:30 UTC | View event → |
| M 4.7 | 98 km SSE of Perryville, Alaska | 34.8 km | 2020-07-22 10:08:38 UTC | View event → |
| M 4.7 | 98 km SSE of Perryville, Alaska | 37.3 km | 2020-07-22 10:08:38 UTC | View event → |
| M 4.5 | 134 km SSE of Perryville, Alaska | 17.6 km | 2020-07-22 10:18:22 UTC | View event → |
| M 4.9 | 56 km SSW of Sand Point, Alaska | 42.6 km | 2020-07-22 11:02:12 UTC | View event → |
| M 4.5 | 120 km SSE of Perryville, Alaska | 13.2 km | 2020-07-22 13:33:38 UTC | View event → |
| M 5.5 | 73 km S of Ivanof Bay, Alaska | 35.6 km | 2020-07-22 21:39:58 UTC | View event → |
| M 5.0 | 57 km ESE of Sand Point, Alaska | 44.9 km | 2020-07-23 11:08:38 UTC | View event → |
| M 4.7 | 54 km S of Sand Point, Alaska | 41.0 km | 2020-07-23 19:56:50 UTC | View event → |
| M 5.0 | 58 km S of Sand Point, Alaska | 43.2 km | 2020-07-24 03:07:08 UTC | View event → |
| M 4.5 | 59 km ESE of Sand Point, Alaska | 44.2 km | 2020-07-24 03:12:58 UTC | View event → |
| M 4.5 | 80 km S of Perryville, Alaska | 42.0 km | 2020-07-24 07:17:31 UTC | View event → |
| M 5.0 | 55 km SSW of Sand Point, Alaska | 45.2 km | 2020-07-24 13:24:39 UTC | View event → |
| M 4.7 | 51 km SSE of Sand Point, Alaska | 38.1 km | 2020-07-26 08:29:22 UTC | View event → |
| M 4.5 | 99 km SSE of Perryville, Alaska | 32.6 km | 2020-07-26 10:00:27 UTC | View event → |
| M 4.9 | 68 km SSE of Sand Point, Alaska | 36.1 km | 2020-07-26 21:35:53 UTC | View event → |
| M 5.5 | 46 km SSE of Sand Point, Alaska | 37.5 km | 2020-07-27 19:34:37 UTC | View event → |
| M 6.1 | 75 km SW of Sand Point, Alaska | 35.2 km | 2020-07-28 08:03:43 UTC | View event → |
| M 5.0 | 49 km SSE of Sand Point, Alaska | 41.9 km | 2020-07-28 12:42:51 UTC | View event → |
| M 5.6 | 44 km SSE of Sand Point, Alaska | 39.0 km | 2020-07-29 09:12:16 UTC | View event → |
| M 4.8 | 82 km SSW of Sand Point, Alaska | 38.3 km | 2020-07-29 13:09:10 UTC | View event → |
| M 5.0 | 134 km SSE of Perryville, Alaska | 33.9 km | 2020-07-30 16:08:18 UTC | View event → |
| M 4.7 | 63 km S of Sand Point, Alaska | 38.6 km | 2020-08-01 07:00:12 UTC | View event → |
| M 4.8 | 89 km SSW of Sand Point, Alaska | 31.0 km | 2020-08-02 14:39:24 UTC | View event → |
| M 5.2 | 79 km SSW of Sand Point, Alaska | 35.0 km | 2020-08-04 12:47:18 UTC | View event → |
Explore clusters of M4.5+ events observed around significant earthquakes. These clusters are descriptive and are not presented as earthquake predictions. Historical small-earthquake detection varies through time. Long-term comparisons are most robust at higher magnitude thresholds.
Guides, explainers and practical reading to go beyond the live data.
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