California earthquakes

M1.8 earthquake 7 km WSW of Cobb, California

A magnitude 1.8 earthquake struck 7 km WSW of Cobb, California on Mon, Dec 28, 1987, 1:38 AM PST (09:38 UTC), 5 km (3 mi) below the surface.

A larger quake followed: M2.0 7 km W of Cobb, California. This one was a foreshock.

Cobb forecastMore in California

Map

Where this earthquake was located, with the others nearby. Select one for its page.

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The earthquake

Magnitude
1.8 (md), micro
Local time
UTC
1987-12-28 09:38:50 UTC
Depth
5.2 km (3.2 mi), shallow
Epicenter
38.795° N, 122.798° W
Tsunami flag
No
Status
Reviewed by a seismologist

Did you feel it?

No one has reported feeling this quake to the USGS.

How well it is located

Reviewed by a seismologist.

Location uncertainty
About 0.6 km horizontally, 1.0 km in depth
Magnitude uncertainty
±0.14
Depth from
From location
Station coverage gap
52°
Stations used
13

Nearest places

Distance and direction from each place to the epicenter, with its forecast.

Nearby

Within 100 km, magnitude 1.5 and up: 169 in the 60 days after this one and 0 in the 30 days before it.

After

  1. 1.56 km WSW of Cobb, California · 14140 days ago · 13 km deep · 1 km away
  2. 1.86 km W of Cobb, California · 14140 days ago · 0 km deep · 3 km away
  3. 2.07 km W of Cobb, California · 14140 days ago · 1 km deep · 4 km away
  4. 1.79 km WSW of Cobb, California · 14140 days ago · -1 km deep · 3 km away
  5. 1.79 km WSW of Cobb, California · 14139 days ago · 1 km deep · 3 km away
  6. 1.79 km W of Cobb, California · 14139 days ago · 1 km deep · 5 km away
  7. 2.08 km W of Cobb, California · 14138 days ago · 0 km deep · 3 km away
  8. 1.811 km SW of Kelseyville, California · 14138 days ago · 6 km deep · 15 km away
  9. 1.88 km W of Cobb, California · 14138 days ago · 1 km deep · 3 km away
  10. 1.75 km W of Cobb, California · 14137 days ago · 0 km deep · 4 km away
  11. 1.54 km WSW of Cobb, California · 14137 days ago · 0 km deep · 2 km away
  12. 1.86 km WNW of Cobb, California · 14136 days ago · 3 km deep · 4 km away
  13. 1.96 km W of Cobb, California · 14136 days ago · 2 km deep · 2 km away
  14. 1.94 km WSW of Cobb, California · 14136 days ago · 2 km deep · 2 km away
  15. 1.86 km SW of Cobb, California · 14136 days ago · 2 km deep · 2 km away
  16. 2.67 km WSW of Cobb, California · 14136 days ago · 1 km deep · 1 km away
  17. 2.27 km WNW of Princeton, California · 14136 days ago · 24 km deep · 93 km away
  18. 1.64 km WNW of Cobb, California · 14136 days ago · 2 km deep · 5 km away
  19. 2.17 km W of Cobb, California · 14135 days ago · 3 km deep · 2 km away
  20. 1.95 km SSW of Cobb, California · 14135 days ago · 1 km deep · 4 km away
  21. 2.46 km W of Cobb, California · 14135 days ago · 3 km deep · 2 km away
  22. 2.217 km ESE of Hidden Valley Lake, California · 14135 days ago · 8 km deep · 36 km away
  23. 1.917 km ESE of Hidden Valley Lake, California · 14135 days ago · 7 km deep · 37 km away
  24. 2.47 km WSW of Cobb, California · 14134 days ago · 1 km deep · 1 km away
  25. 1.67 km WSW of Cobb, California · 14134 days ago · 1 km deep · 1 km away
  26. 1.86 km WSW of Cobb, California · 14134 days ago · -1 km deep · 1 km away
  27. 2.16 km SSW of Cobb, California · 14134 days ago · -1 km deep · 5 km away
  28. 1.86 km WNW of Cobb, California · 14133 days ago · 0 km deep · 5 km away
  29. 1.616 km ENE of Angwin, CA · 14133 days ago · 8 km deep · 50 km away
  30. 1.77 km WSW of Cobb, California · 14133 days ago · 1 km deep · 1 km away
  31. 1.78 km W of Cobb, California · 14133 days ago · 1 km deep · 3 km away
  32. 1.65 km WNW of Cobb, California · 14132 days ago · 2 km deep · 5 km away
  33. 1.50 km ENE of Benicia, California · 14132 days ago · 8 km deep · 100 km away
  34. 1.65 km SSW of Cobb, California · 14131 days ago · -1 km deep · 4 km away
  35. 1.78 km WSW of Cobb, California · 14131 days ago · 3 km deep · 1 km away
  36. 2.28 km W of Cobb, California · 14131 days ago · 1 km deep · 5 km away
  37. 1.56 km WSW of Cobb, California · 14130 days ago · 3 km deep · 1 km away
  38. 1.84 km WSW of Cobb, California · 14130 days ago · 1 km deep · 2 km away
  39. 2.014 km WSW of Geyserville, California · 14130 days ago · 4 km deep · 27 km away
  40. 2.65 km WNW of Cobb, California · 14130 days ago · 2 km deep · 4 km away
  41. 1.75 km W of Cobb, California · 14130 days ago · 1 km deep · 4 km away
  42. 1.55 km W of Cobb, California · 14130 days ago · 1 km deep · 3 km away
  43. 1.87 km W of Cobb, California · 14130 days ago · 1 km deep · 5 km away
  44. 1.68 km W of Cobb, California · 14130 days ago · 1 km deep · 5 km away
  45. 1.712 km NW of Guinda, California · 14129 days ago · 9 km deep · 45 km away
  46. 2.34 km NNW of Redwood Valley, California · 14129 days ago · 9 km deep · 67 km away
  47. 2.48 km W of Cobb, California · 14128 days ago · -1 km deep · 5 km away
  48. 1.77 km WSW of Cobb, California · 14128 days ago · 1 km deep · 1 km away
  49. 2.02 km WSW of Geyserville, California · 14128 days ago · 11 km deep · 15 km away
  50. 1.611 km W of Cobb, California · 14128 days ago · 0 km deep · 6 km away
  51. 1.98 km WSW of Cobb, California · 14127 days ago · 0 km deep · 2 km away
  52. 3.05 km WNW of Cobb, California · 14127 days ago · -1 km deep · 4 km away
  53. 2.85 km W of Cobb, California · 14127 days ago · 0 km deep · 4 km away
  54. 1.95 km W of Cobb, California · 14127 days ago · 1 km deep · 4 km away
  55. 3.17 km WSW of Cobb, California · 14127 days ago · 1 km deep · 1 km away
  56. 3.17 km WSW of Cobb, California · 14126 days ago · 2 km deep · 1 km away
  57. 1.77 km WSW of Cobb, California · 14126 days ago · 1 km deep · 1 km away
  58. 1.78 km W of Cobb, California · 14126 days ago · 0 km deep · 3 km away
  59. 1.78 km SSW of Cobb, California · 14126 days ago · 3 km deep · 6 km away
  60. 2.8Northern California · 14126 days ago · 1 km deep · 2 km away

The first 60 of 169.

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Sources

From the USGS Earthquake Hazards Program and its partner networks, event nc1154534. Read Tue, Sep 22, 2026, 10:55 AM UTC.