California earthquakes

M1.5 earthquake 8 km WSW of Cobb, California

A magnitude 1.5 earthquake struck 8 km WSW of Cobb, California on Wed, Apr 20, 1983, 1:51 AM PST (09:51 UTC), 6 km (3 mi) below the surface.

A larger quake followed: M3.4 7 km WSW 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.

Open the live map with earthquakes

The earthquake

Magnitude
1.5 (Md, duration), micro
Magnitude from
Northern California Seismic System
Local time
UTC
1983-04-20 09:51:24 UTC
Depth
5.6 km (3.5 mi), shallow
Epicenter
38.793° N, 122.815° 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 0.9 km horizontally, 2.2 km in depth
Magnitude uncertainty
±0.09
Depth from
From location
Station coverage gap
175°
Stations used
10

Nearest places

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

Nearby

Within 100 km, magnitude 1.5 and up: 140 in the 60 days after this one and 72 in the 30 days before it.

After

  1. 1.95 km SSW of Cobb, California · 15871 days ago · -1 km deep · 7 km away
  2. 2.012 km ENE of Hidden Valley Lake, California · 15870 days ago · 6 km deep · 34 km away
  3. 3.118 km E of Potter Valley, California · 15870 days ago · 10 km deep · 62 km away
  4. 1.818 km E of Potter Valley, California · 15870 days ago · 8 km deep · 62 km away
  5. 1.65 km SW of Cobb, California · 15870 days ago · 0 km deep · 4 km away
  6. 2.14 km SW of Cobb, California · 15870 days ago · -1 km deep · 5 km away
  7. 2.04 km SSE of Clear Lake Riviera, California · 15870 days ago · 3 km deep · 17 km away
  8. 1.86 km W of Kenwood, California · 15869 days ago · 8 km deep · 47 km away
  9. 1.55 km ENE of Willits, California · 15869 days ago · 3 km deep · 83 km away
  10. 1.69 km ESE of Hidden Valley Lake, California · 15869 days ago · 4 km deep · 31 km away
  11. 1.84 km S of Cobb, California · 15869 days ago · 1 km deep · 8 km away
  12. 1.94 km S of Cobb, California · 15869 days ago · 2 km deep · 8 km away
  13. 2.56 km WSW of Cobb, California · 15868 days ago · 0 km deep · 2 km away
  14. 1.96 km WSW of Cobb, California · 15868 days ago · 1 km deep · 2 km away
  15. 1.6near the coast of Northern California · 15868 days ago · 3 km deep · 58 km away
  16. 1.77 km WSW of Cobb, California · 15867 days ago · 3 km deep · 2 km away
  17. 2.26 km SW of Cobb, California · 15867 days ago · 0 km deep · 3 km away
  18. 1.88 km SW of Calistoga, California · 15867 days ago · 4 km deep · 34 km away
  19. 1.63 km ENE of Calistoga, California · 15866 days ago · 4 km deep · 33 km away
  20. 2.110 km ENE of Cloverdale, California · 15865 days ago · 4 km deep · 9 km away
  21. 1.53 km ENE of Calistoga, California · 15865 days ago · 0 km deep · 32 km away
  22. 2.07 km WSW of Cobb, California · 15865 days ago · 0 km deep · 1 km away
  23. 1.920 km NE of Potter Valley, California · 15864 days ago · 13 km deep · 72 km away
  24. 2.06 km WSW of Cobb, California · 15863 days ago · 3 km deep · 2 km away
  25. 1.89 km NNE of Brooktrails, California · 15863 days ago · 8 km deep · 92 km away
  26. 1.85 km W of Cobb, California · 15862 days ago · 2 km deep · 3 km away
  27. 2.17 km W of Cobb, California · 15862 days ago · 3 km deep · 2 km away
  28. 1.57 km W of Cobb, California · 15862 days ago · 3 km deep · 3 km away
  29. 1.88 km W of Cobb, California · 15862 days ago · 3 km deep · 2 km away
  30. 1.618 km NE of Upper Lake, California · 15861 days ago · 10 km deep · 56 km away
  31. 1.62 km NE of Clearlake, California · 15861 days ago · -1 km deep · 27 km away
  32. 1.64 km SW of Cobb, California · 15861 days ago · -1 km deep · 4 km away
  33. 2.09 km WSW of Cobb, California · 15858 days ago · 2 km deep · 1 km away
  34. 2.47 km WSW of Cobb, California · 15858 days ago · 2 km deep · 1 km away
  35. 1.53 km E of Hopland, California · 15857 days ago · 1 km deep · 30 km away
  36. 1.67 km WSW of Cobb, California · 15856 days ago · 3 km deep · 1 km away
  37. 1.67 km WSW of Cobb, California · 15856 days ago · 3 km deep · 1 km away
  38. 1.91 km SE of Calpella, California · 15855 days ago · 3 km deep · 58 km away
  39. 1.62 km SE of Clear Lake Riviera, California · 15854 days ago · 1 km deep · 19 km away
  40. 2.05 km W of Cobb, California · 15854 days ago · 0 km deep · 5 km away
  41. 2.28 km WSW of Cobb, California · 15854 days ago · 3 km deep · 1 km away
  42. 1.72 km SE of Clear Lake Riviera, California · 15854 days ago · 0 km deep · 19 km away
  43. 1.618 km NE of Sea Ranch, California · 15854 days ago · 9 km deep · 43 km away
  44. 1.77 km W of Cobb, California · 15853 days ago · 5 km deep · 3 km away
  45. 1.922 km NNE of Potter Valley, California · 15853 days ago · 5 km deep · 81 km away
  46. 1.524 km SE of Covelo, California · 15852 days ago · 5 km deep · 94 km away
  47. 1.826 km N of Potter Valley, California · 15852 days ago · 0 km deep · 89 km away
  48. 1.77 km W of Cobb, California · 15852 days ago · 2 km deep · 2 km away
  49. 1.96 km SW of Cobb, California · 15849 days ago · 1 km deep · 4 km away
  50. 1.79 km E of Geyserville, California · 15849 days ago · 5 km deep · 10 km away
  51. 1.99 km W of Calpella, California · 15848 days ago · 14 km deep · 65 km away
  52. 1.76 km WSW of Cobb, California · 15847 days ago · 2 km deep · 2 km away
  53. 1.55 km SW of Cobb, California · 15846 days ago · 1 km deep · 3 km away
  54. 2.35 km SW of Cobb, California · 15844 days ago · 0 km deep · 4 km away
  55. 1.65 km W of Cobb, California · 15844 days ago · 1 km deep · 5 km away
  56. 1.87 km W of Cobb, California · 15844 days ago · 3 km deep · 3 km away
  57. 1.86 km SW of Cobb, California · 15843 days ago · 3 km deep · 3 km away
  58. 1.67 km WSW of Cobb, California · 15842 days ago · 1 km deep · 2 km away
  59. 1.714 km WSW of Calpella, California · 15842 days ago · 2 km deep · 66 km away
  60. 2.213 km SW of Willits, California · 15841 days ago · 0 km deep · 80 km away

The first 60 of 140.

Before

  1. 1.57 km WSW of Cobb, California · 15872 days ago · 3 km deep · 1 km away
  2. 3.47 km WSW of Cobb, California · 15872 days ago · 4 km deep · 1 km away
  3. 1.94 km S of Cobb, California · 15872 days ago · 1 km deep · 8 km away
  4. 1.56 km W of Cobb, California · 15873 days ago · 3 km deep · 3 km away
  5. 1.85 km SW of Kenwood, California · 15873 days ago · 11 km deep · 50 km away
  6. 3.56 km W of Cobb, California · 15873 days ago · 3 km deep · 4 km away
  7. 1.97 km WSW of Cobb, California · 15873 days ago · 0 km deep · 1 km away
  8. 1.922 km NE of Potter Valley, California · 15874 days ago · 6 km deep · 76 km away
  9. 1.67 km WSW of Cobb, California · 15874 days ago · 1 km deep · 2 km away
  10. 1.67 km WSW of Cobb, California · 15875 days ago · 1 km deep · 1 km away
  11. 1.69 km W of Cobb, California · 15876 days ago · 1 km deep · 4 km away
  12. 2.77 km WSW of Cobb, California · 15876 days ago · 2 km deep · 2 km away
  13. 1.95 km SW of Cobb, California · 15877 days ago · 0 km deep · 4 km away
  14. 2.28 km WSW of Cobb, California · 15877 days ago · 1 km deep · 1 km away
  15. 3.07 km W of Cobb, California · 15877 days ago · 2 km deep · 2 km away
  16. 3.27 km WSW of Cobb, California · 15877 days ago · 3 km deep · 2 km away
  17. 2.26 km SW of Cobb, California · 15878 days ago · 1 km deep · 4 km away
  18. 1.611 km NNE of Brooktrails, California · 15878 days ago · 11 km deep · 95 km away
  19. 1.68 km NNE of Larkfield-Wikiup, California · 15878 days ago · 4 km deep · 26 km away
  20. 1.97 km W of Cobb, California · 15878 days ago · 3 km deep · 2 km away

Earthquakes todayCalifornia earthquakesLive radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event nc1090636. Read Fri, Oct 2, 2026, 8:08 PM UTC.