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Earthquakes / EVENT RECORD

M 4.8 - 97 km W of Petrolia, CA

USGS · Every measurement below belongs to the selected record.

Captured 2026-09-30 22:14:41 UTC

Around the epicentre

Regional view · markers are locations, not affected areas

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● This earthquake ● Nearby recorded activityRegional map

Magnitude

M 4.77

Scale: mw

Depth

10 km

operator assigned

Reported by people

20

Number of felt reports

USGS review

reviewed

Review does not imply final measurements

What the record tells us

USGS reports a magnitude 4.77 earthquake in 97 km W of Petrolia, CA, at a depth of 10 km.

Detailed source data captured 2026-09-30 22:14:41 UTC.

Measurements & confidence

Event time (UTC)
2026-09-29 11:36:39.240 UTC
Source updated (UTC)
2026-09-30 11:46:40.665 UTC
Location
40.422°, -125.418°
Stations used for location
152
Horizontal error
1.11 km
Depth error
31.61 km
Magnitude error
Not published

Errors are the source’s reported uncertainty estimates, not guaranteed bounds. A depth marked “operator assigned” was fixed during analysis.

Shaking & impact

Instrumental intensity
2.268 MMI
Felt-report intensity
3.1 CDI
PAGER impact alert
green

No published assessment does not mean no shaking or no impact. A magnitude value alone cannot establish damage or a tsunami warning.

Shaking map · available at USGS ↗
PAGER impact assessment · available at USGS ↗
Did You Feel It? reports · available at USGS ↗
Fault-motion solution · available at USGS ↗
USGS shaking intensity map for this earthquake
Official USGS ShakeMap product. Follow USGS for revisions.

Nearby seismic activity

Within 500 km · M2.5+ · seven days before the event through the latest query, up to seven days after

13 nearby records

Query window: 2026-09-22 11:36:39 to 2026-09-30 22:14:41 UTC. This is spatial proximity, not an identified aftershock sequence.

M3.08 km ESE of Cloverdale, CA2026-09-30 21:07:19 UTC
281 km away · 4.03000020980835 km deep ↗
M2.61 km SW of Anderson Springs, CA2026-09-30 20:48:14 UTC
297 km away · 1.78999996185303 km deep ↗
M2.66 km W of Yountville, CA2026-09-29 16:06:37 UTC
342 km away · 8.30000019073486 km deep ↗
M3.2275 km W of Indianola, California2026-09-28 13:30:32 UTC
189 km away · 10 km deep ↗
M2.7199 km W of Gold Beach, Oregon2026-09-28 08:45:20 UTC
236 km away · 10 km deep ↗
M2.69 km NW of Redwood Valley, CA2026-09-27 19:10:36 UTC
220 km away · -0.379999995231628 km deep ↗
M2.626 km WSW of Westley, CA2026-09-27 14:40:46 UTC
478 km away · 2.70000004768372 km deep ↗
M3.327 km WSW of Westley, CA2026-09-27 14:21:50 UTC
479 km away · 3.37 km deep ↗
M2.710 km W of Boonville, CA2026-09-26 04:02:07 UTC
228 km away · 3.46000003814697 km deep ↗
M3.710 km W of Boonville, CA2026-09-26 03:42:49 UTC
228 km away · 4.78 km deep ↗
M2.81 km WNW of Sun Valley, Nevada2026-09-23 05:33:37 UTC
488 km away · 5.092 km deep ↗
M2.540 km W of Petrolia, CA2026-09-22 19:00:08 UTC
57 km away · 2 km deep ↗
M2.647 km WNW of Petrolia, CA2026-09-22 15:23:58 UTC
52 km away · 26.3600006103516 km deep ↗
View the USGS catalogue query ↗

The record as it develops

This timeline begins when our journal started capturing details. It is not a complete USGS revision history.

  1. Captured 2026-09-29 11:59:40 UTC

    First detailed capture · M4.73 · 2.27999997138977 km deep · 10 nearby records

    Source updated 2026-09-29 11:59:02 UTC

  2. Captured 2026-09-29 12:14:40 UTC

    Updated capture · M4.73 · 2.27999997138977 km deep · 10 nearby records

    Source updated 2026-09-29 12:09:59 UTC

  3. Captured 2026-09-29 12:29:45 UTC

    Updated capture · M4.73 · 2.27999997138977 km deep · 10 nearby records

    Source updated 2026-09-29 12:25:26 UTC

  4. Captured 2026-09-29 12:44:43 UTC

    Updated capture · M4.73 · 2.27999997138977 km deep · 10 nearby records

    Source updated 2026-09-29 12:40:33 UTC

  5. Captured 2026-09-29 12:59:40 UTC

    Updated capture · M4.73 · 2.27999997138977 km deep · 10 nearby records

    Source updated 2026-09-29 12:56:57 UTC

  6. Captured 2026-09-29 13:29:41 UTC

    Updated capture · M4.73 · 2.27999997138977 km deep · 10 nearby records

    Source updated 2026-09-29 13:22:26 UTC

  7. Captured 2026-09-29 13:44:40 UTC

    Updated capture · M4.73 · 2.27999997138977 km deep · 10 nearby records

    Source updated 2026-09-29 13:42:38 UTC

  8. Captured 2026-09-29 13:59:40 UTC

    Updated capture · M4.73 · 2.27999997138977 km deep · 10 nearby records

    Source updated 2026-09-29 13:57:52 UTC

  9. Captured 2026-09-29 14:59:42 UTC

    Updated capture · M4.73 · 2.27999997138977 km deep · 10 nearby records

    Source updated 2026-09-29 13:57:52 UTC

  10. Captured 2026-09-29 15:59:40 UTC

    Updated capture · M4.73 · 2.27999997138977 km deep · 10 nearby records

    Source updated 2026-09-29 15:53:55 UTC

  11. Captured 2026-09-29 16:29:40 UTC

    Updated capture · M4.73 · 2.27999997138977 km deep · 11 nearby records

    Source updated 2026-09-29 16:29:27 UTC

  12. Captured 2026-09-29 16:44:41 UTC

    Updated capture · M4.73 · 2.27999997138977 km deep · 11 nearby records

    Source updated 2026-09-29 16:29:27 UTC

  13. Captured 2026-09-29 16:59:40 UTC

    Updated capture · M4.73 · 10 km deep · 11 nearby records

    Source updated 2026-09-29 16:57:43 UTC

  14. Captured 2026-09-29 17:14:40 UTC

    Updated capture · M4.73 · 10 km deep · 11 nearby records

    Source updated 2026-09-29 17:07:23 UTC

  15. Captured 2026-09-29 17:29:40 UTC

    Updated capture · M4.73 · 10 km deep · 11 nearby records

    Source updated 2026-09-29 17:17:30 UTC

  16. Captured 2026-09-29 17:44:43 UTC

    Updated capture · M4.73 · 10 km deep · 11 nearby records

    Source updated 2026-09-29 17:41:03 UTC

  17. Captured 2026-09-29 17:59:41 UTC

    Updated capture · M4.73 · 10 km deep · 11 nearby records

    Source updated 2026-09-29 17:46:42 UTC

  18. Captured 2026-09-29 19:14:43 UTC

    Updated capture · M4.73 · 10 km deep · 11 nearby records

    Source updated 2026-09-29 17:46:42 UTC

  19. Captured 2026-09-29 20:14:41 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-29 20:12:57 UTC

  20. Captured 2026-09-29 20:44:41 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-29 20:31:44 UTC

  21. Captured 2026-09-29 21:14:41 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-29 21:05:49 UTC

  22. Captured 2026-09-29 22:29:40 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-29 21:05:49 UTC

  23. Captured 2026-09-29 23:37:14 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-29 21:05:49 UTC

  24. Captured 2026-09-29 23:52:17 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-29 23:46:46 UTC

  25. Captured 2026-09-30 01:07:16 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-29 23:46:46 UTC

  26. Captured 2026-09-30 02:22:15 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-29 23:46:46 UTC

  27. Captured 2026-09-30 03:37:14 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-30 03:31:03 UTC

  28. Captured 2026-09-30 04:52:14 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-30 03:31:03 UTC

  29. Captured 2026-09-30 05:52:14 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-30 05:46:44 UTC

  30. Captured 2026-09-30 06:07:15 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-30 05:56:14 UTC

  31. Captured 2026-09-30 07:22:14 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-30 05:56:14 UTC

  32. Captured 2026-09-30 08:26:57 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-30 05:56:14 UTC

  33. Captured 2026-09-30 09:41:57 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-30 05:56:14 UTC

  34. Captured 2026-09-30 10:41:58 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-30 05:56:14 UTC

  35. Captured 2026-09-30 11:41:59 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-30 11:41:10 UTC

  36. Captured 2026-09-30 12:56:57 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-30 11:46:40 UTC

  37. Captured 2026-09-30 14:14:40 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-30 11:46:40 UTC

  38. Captured 2026-09-30 15:14:47 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-30 11:46:40 UTC

  39. Captured 2026-09-30 16:29:40 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-30 11:46:40 UTC

  40. Captured 2026-09-30 17:29:41 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-30 11:46:40 UTC

  41. Captured 2026-09-30 18:44:40 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-30 11:46:40 UTC

  42. Captured 2026-09-30 19:44:42 UTC

    Updated capture · M4.77 · 10 km deep · 11 nearby records

    Source updated 2026-09-30 11:46:40 UTC

  43. Captured 2026-09-30 20:59:42 UTC

    Updated capture · M4.77 · 10 km deep · 12 nearby records

    Source updated 2026-09-30 11:46:40 UTC

  44. Captured 2026-09-30 22:14:41 UTC

    Updated capture · M4.77 · 10 km deep · 13 nearby records

    Source updated 2026-09-30 11:46:40 UTC

Magnitude is not shaking

Magnitude describes the earthquake’s size. The shaking experienced at a place depends on distance, depth, local ground conditions and the rupture.

Depth needs context

A reported depth describes the location of the earthquake underground. Some solutions use an assigned depth; uncertainty and review status matter.

Nearby does not mean aftershock

Our regional search finds events by distance and time. Establishing an aftershock sequence requires seismological assessment.

Read the original USGS record ↗

This is a source-linked archive. Source measurements and assessments can change. An archived bulletin is not evidence that a warning is currently active.

In the daily journal

30 September 2026 ↗29 September 2026 ↗

SOURCE ID usgs:nc75444322