M3.0 earthquake 5 km SW of Cobb, California

Magnitude

3.0 (ml), minor

Local time

Tue, Dec 18, 1984, 6:40 PM PST

UTC

1984-12-19 02:40:01 UTC

Depth

0.8 km (0.5 mi), shallow

Epicenter

38.791° N, 122.774° W

Region

California

Tsunami flag

No

Status

Reviewed by a seismologist

Location uncertainty

About 0.1 km horizontally, 0.2 km in depth

Depth from

From location

Station coverage gap

46°

Stations used

35

• Cobb, CaliforniaPopulation 1,778. Forecast6 kmSW
• Healdsburg, CaliforniaPopulation 11,742. Forecast22 kmNNE
• Santa Rosa, CaliforniaPopulation 178,127. Forecast39 kmN
• Los Angeles, CaliforniaPopulation 3,820,914. Forecast665 kmNW

After

1. 3.06 km W of Cobb, CaliforniaSat, Dec 29, 8:21 AM PST · 15242 days ago · 3 km deep · 4 km away
2. 2.77 km WSW of Cobb, CaliforniaSat, Dec 29, 3:50 PM PST · 15242 days ago · 1 km deep · 3 km away
3. 1.94 km WSW of Cobb, CaliforniaSat, Dec 29, 4:10 PM PST · 15242 days ago · 1 km deep · 2 km away
4. 1.89 km NNW of Redwood Valley, CaliforniaSat, Dec 29, 7:53 PM PST · 15241 days ago · 7 km deep · 74 km away
5. 1.66 km W of Cobb, CaliforniaSun, Dec 30, 4:38 AM PST · 15241 days ago · 2 km deep · 3 km away
6. 1.916 km ENE of Potter Valley, CaliforniaSun, Dec 30, 9:29 AM PST · 15241 days ago · 6 km deep · 68 km away
7. 1.87 km W of Cobb, CaliforniaSun, Dec 30, 6:11 PM PST · 15240 days ago · 0 km deep · 4 km away
8. 2.07 km W of Cobb, CaliforniaSun, Dec 30, 8:13 PM PST · 15240 days ago · 1 km deep · 4 km away
9. 1.610 km WNW of Potter Valley, CaliforniaMon, Dec 31, 1:28 AM PST · 15240 days ago · 7 km deep · 75 km away
10. 1.67 km WSW of Cobb, CaliforniaMon, Dec 31, 3:38 PM PST · 15240 days ago · 0 km deep · 3 km away
11. 1.66 km W of Cobb, CaliforniaMon, Dec 31, 6:49 PM PST · 15239 days ago · 1 km deep · 5 km away
12. 1.66 km WSW of Cobb, CaliforniaMon, Dec 31, 7:03 PM PST · 15239 days ago · 0 km deep · 3 km away
13. 1.67 km WSW of Cobb, CaliforniaTue, Jan 1, 11:21 PM PST · 15238 days ago · 3 km deep · 3 km away
14. 2.48 km WSW of Cobb, CaliforniaWed, Jan 2, 5:12 AM PST · 15238 days ago · -1 km deep · 4 km away
15. 2.45 km W of Cobb, CaliforniaWed, Jan 2, 3:12 PM PST · 15238 days ago · 0 km deep · 4 km away
16. 1.75 km W of Cobb, CaliforniaWed, Jan 2, 3:12 PM PST · 15238 days ago · 0 km deep · 4 km away
17. 1.75 km SW of Cobb, CaliforniaWed, Jan 2, 5:53 PM PST · 15237 days ago · 1 km deep · 0 km away
18. 1.96 km W of Cobb, CaliforniaThu, Jan 3, 5:17 AM PST · 15237 days ago · 3 km deep · 4 km away
19. 1.89 km W of Cobb, CaliforniaThu, Jan 3, 7:39 AM PST · 15237 days ago · 0 km deep · 5 km away
20. 1.87 km WSW of Cobb, CaliforniaThu, Jan 3, 10:36 PM PST · 15236 days ago · 2 km deep · 3 km away
21. 2.28 km W of Cobb, CaliforniaFri, Jan 4, 4:05 AM PST · 15236 days ago · 0 km deep · 6 km away
22. 2.54 km ENE of Geyserville, CaliforniaFri, Jan 4, 1:07 PM PST · 15236 days ago · 14 km deep · 10 km away
23. 2.220 km NNE of Upper Lake, CaliforniaFri, Jan 4, 4:49 PM PST · 15235 days ago · 7 km deep · 62 km away
24. 1.65 km NNW of Hidden Valley Lake, CaliforniaSat, Jan 5, 9:58 AM PST · 15235 days ago · 7 km deep · 18 km away
25. 1.619 km ENE of Potter Valley, CaliforniaSat, Jan 5, 8:36 PM PST · 15234 days ago · 10 km deep · 67 km away
26. 2.35 km SW of Cobb, CaliforniaSun, Jan 6, 10:16 AM PST · 15234 days ago · 1 km deep · 0 km away
27. 1.64 km WSW of Cobb, CaliforniaSun, Jan 6, 3:39 PM PST · 15234 days ago · 1 km deep · 1 km away
28. 1.96 km W of Cobb, CaliforniaSun, Jan 6, 6:17 PM PST · 15233 days ago · 1 km deep · 4 km away
29. 2.48 km WSW of Cobb, CaliforniaMon, Jan 7, 4:30 AM PST · 15233 days ago · 3 km deep · 4 km away
30. 1.53 km WNW of Cobb, CaliforniaMon, Jan 7, 2:08 PM PST · 15233 days ago · 2 km deep · 4 km away
31. 1.76 km W of Cobb, CaliforniaMon, Jan 7, 3:21 PM PST · 15233 days ago · 4 km deep · 4 km away
32. 1.56 km WSW of Cobb, CaliforniaTue, Jan 8, 1:41 AM PST · 15232 days ago · 0 km deep · 2 km away
33. 1.97 km W of Cobb, CaliforniaTue, Jan 8, 2:38 AM PST · 15232 days ago · 0 km deep · 5 km away
34. 1.916 km ENE of Potter Valley, CaliforniaTue, Jan 8, 2:07 PM PST · 15232 days ago · 7 km deep · 69 km away
35. 1.5Northern CaliforniaTue, Jan 8, 2:30 PM PST · 15232 days ago · 1 km deep · 7 km away
36. 1.88 km W of Cobb, CaliforniaTue, Jan 8, 6:58 PM PST · 15231 days ago · 0 km deep · 6 km away
37. 1.75 km W of Cobb, CaliforniaWed, Jan 9, 10:52 AM PST · 15231 days ago · 1 km deep · 4 km away
38. 1.77 km WSW of Cobb, CaliforniaWed, Jan 9, 1:19 PM PST · 15231 days ago · 3 km deep · 3 km away
39. 1.58 km W of Cobb, CaliforniaWed, Jan 9, 1:19 PM PST · 15231 days ago · 1 km deep · 6 km away
40. 1.6Northern CaliforniaWed, Jan 9, 7:40 PM PST · 15230 days ago · 0 km deep · 1 km away
41. 1.74 km NNW of Geyserville, CaliforniaWed, Jan 9, 10:22 PM PST · 15230 days ago · 3 km deep · 13 km away
42. 1.98 km W of Cobb, CaliforniaThu, Jan 10, 12:47 AM PST · 15230 days ago · 0 km deep · 5 km away
43. 1.76 km W of Cobb, CaliforniaThu, Jan 10, 1:07 AM PST · 15230 days ago · 3 km deep · 4 km away
44. 1.57 km WSW of Cobb, CaliforniaThu, Jan 10, 10:26 AM PST · 15230 days ago · 2 km deep · 3 km away
45. 2.06 km W of Cobb, CaliforniaThu, Jan 10, 12:42 PM PST · 15230 days ago · 2 km deep · 3 km away
46. 2.16 km W of Cobb, CaliforniaThu, Jan 10, 5:07 PM PST · 15229 days ago · 3 km deep · 4 km away
47. 1.613 km E of Angwin, CaliforniaThu, Jan 10, 9:39 PM PST · 15229 days ago · 2 km deep · 48 km away
48. 1.75 km SW of Cobb, CaliforniaFri, Jan 11, 6:47 AM PST · 15229 days ago · 1 km deep · 2 km away
49. 1.86 km WSW of Cobb, CaliforniaFri, Jan 11, 7:59 AM PST · 15229 days ago · 0 km deep · 2 km away
50. 2.24 km W of Cobb, CaliforniaFri, Jan 11, 5:56 PM PST · 15228 days ago · 0 km deep · 3 km away
51. 1.54 km W of Cobb, CaliforniaFri, Jan 11, 5:57 PM PST · 15228 days ago · 0 km deep · 3 km away
52. 1.52 km WNW of Clear Lake Riviera, CaliforniaFri, Jan 11, 7:05 PM PST · 15228 days ago · 4 km deep · 19 km away
53. 2.04 km WSW of Cobb, CaliforniaSat, Jan 12, 5:16 AM PST · 15228 days ago · 1 km deep · 1 km away
54. 1.64 km SSW of Clear Lake Riviera, CaliforniaSat, Jan 12, 6:17 AM PST · 15228 days ago · -1 km deep · 14 km away
55. 1.66 km W of Cobb, CaliforniaSat, Jan 12, 2:50 PM PST · 15228 days ago · 3 km deep · 4 km away
56. 2.19 km SW of Hopland, CaliforniaSat, Jan 12, 5:50 PM PST · 15227 days ago · 14 km deep · 37 km away
57. 2.26 km WNW of Potter Valley, CaliforniaSat, Jan 12, 7:49 PM PST · 15227 days ago · 5 km deep · 71 km away
58. 1.86 km WSW of Cobb, CaliforniaSat, Jan 12, 9:36 PM PST · 15227 days ago · 1 km deep · 2 km away
59. 1.56 km W of Cobb, CaliforniaSat, Jan 12, 11:32 PM PST · 15227 days ago · 3 km deep · 4 km away
60. 1.520 km NNE of Upper Lake, CaliforniaSun, Jan 13, 1:21 PM PST · 15227 days ago · 5 km deep · 62 km away

The first 60 of 197.

From the USGS Earthquake Hazards Program and its partner networks, event nc39437 (also filed as usp0002a7d). Read Tue, Sep 22, 2026, 12:16 PM UTC.