M1.8 earthquake 6 km W of Cobb, California

Magnitude

1.8 (Md, duration), micro

Magnitude from

Northern California Seismic System

Local time

Sun, Apr 12, 1987, 9:35 PM PDT

UTC

1987-04-13 04:35:31 UTC

Depth

3.0 km (1.8 mi), shallow

Epicenter

38.821° N, 122.796° W

Region

California

Tsunami flag

No

Status

Reviewed by a seismologist

Location uncertainty

About 0.2 km horizontally, 0.4 km in depth

Magnitude uncertainty

±0.16

Depth from

From location

Station coverage gap

61°

Stations used

19

• Cobb, CaliforniaPopulation 1,778. Forecast6 kmW
• Clearlake, CaliforniaPopulation 15,182. Forecast21 kmSW
• Santa Rosa, CaliforniaPopulation 178,127. Forecast43 kmN
• Los Angeles, CaliforniaPopulation 3,820,914. Forecast668 kmNW

After

1. 1.62 km ESE of Calpella, CaliforniaMon, Apr 13, 2:36 AM PDT · 14417 days ago · 5 km deep · 56 km away
2. 1.97 km W of Cobb, CaliforniaMon, Apr 13, 4:48 AM PDT · 14417 days ago · 4 km deep · 1 km away
3. 1.87 km W of Cobb, CaliforniaMon, Apr 13, 5:31 AM PDT · 14417 days ago · 4 km deep · 1 km away
4. 2.06 km SW of Cobb, CaliforniaTue, Apr 14, 10:42 AM PDT · 14416 days ago · 3 km deep · 4 km away
5. 1.67 km W of Cobb, CaliforniaTue, Apr 14, 9:02 PM PDT · 14415 days ago · 3 km deep · 2 km away
6. 1.65 km SW of Cobb, CaliforniaTue, Apr 14, 10:39 PM PDT · 14415 days ago · 0 km deep · 5 km away
7. 1.66 km W of Cobb, CaliforniaTue, Apr 14, 11:45 PM PDT · 14415 days ago · 2 km deep · 0 km away
8. 1.87 km WSW of Cobb, CaliforniaWed, Apr 15, 3:43 AM PDT · 14415 days ago · 1 km deep · 2 km away
9. 1.95 km SSW of Cobb, CaliforniaWed, Apr 15, 6:27 AM PDT · 14415 days ago · 0 km deep · 6 km away
10. 1.67 km W of Cobb, CaliforniaWed, Apr 15, 2:32 PM PDT · 14414 days ago · 1 km deep · 2 km away
11. 1.83 km W of Cobb, CaliforniaWed, Apr 15, 5:51 PM PDT · 14414 days ago · 1 km deep · 3 km away
12. 1.86 km SW of Cobb, CaliforniaWed, Apr 15, 6:51 PM PDT · 14414 days ago · 2 km deep · 4 km away
13. 2.16 km W of Cobb, CaliforniaWed, Apr 15, 10:16 PM PDT · 14414 days ago · 3 km deep · 0 km away
14. 2.14 km SW of Cobb, CaliforniaThu, Apr 16, 3:02 AM PDT · 14414 days ago · 0 km deep · 5 km away
15. 2.25 km W of Cobb, CaliforniaThu, Apr 16, 3:32 PM PDT · 14413 days ago · 1 km deep · 1 km away
16. 1.65 km SW of Cobb, CaliforniaThu, Apr 16, 6:18 PM PDT · 14413 days ago · -1 km deep · 5 km away
17. 1.54 km SW of Cobb, CaliforniaThu, Apr 16, 8:43 PM PDT · 14413 days ago · 0 km deep · 5 km away
18. 1.79 km WNW of Cobb, CaliforniaFri, Apr 17, 11:46 AM PDT · 14413 days ago · 1 km deep · 4 km away
19. 1.76 km W of Cobb, CaliforniaSat, Apr 18, 5:09 PM PDT · 14411 days ago · 2 km deep · 1 km away
20. 1.64 km SW of Cobb, CaliforniaSat, Apr 18, 9:38 PM PDT · 14411 days ago · 0 km deep · 5 km away
21. 2.35 km SW of Cobb, CaliforniaSat, Apr 18, 9:58 PM PDT · 14411 days ago · 1 km deep · 4 km away
22. 1.513 km NNE of Angwin, CaliforniaSun, Apr 19, 6:44 PM PDT · 14410 days ago · 4 km deep · 38 km away
23. 1.76 km WSW of Cobb, CaliforniaMon, Apr 20, 9:37 AM PDT · 14410 days ago · 4 km deep · 2 km away
24. 2.27 km WSW of Cobb, CaliforniaMon, Apr 20, 10:57 AM PDT · 14410 days ago · 1 km deep · 3 km away
25. 2.38 km WSW of Cobb, CaliforniaMon, Apr 20, 1:20 PM PDT · 14409 days ago · 1 km deep · 3 km away
26. 2.86 km W of Cobb, CaliforniaMon, Apr 20, 2:58 PM PDT · 14409 days ago · 2 km deep · 1 km away
27. 2.17 km W of Cobb, CaliforniaTue, Apr 21, 4:08 AM PDT · 14409 days ago · 3 km deep · 1 km away
28. 1.512 km NE of Lucerne, CaliforniaTue, Apr 21, 8:50 AM PDT · 14409 days ago · 13 km deep · 41 km away
29. 1.811 km NNE of Geyserville, CaliforniaTue, Apr 21, 9:29 AM PDT · 14409 days ago · 3 km deep · 5 km away
30. 1.77 km W of Cobb, CaliforniaTue, Apr 21, 6:26 PM PDT · 14408 days ago · 3 km deep · 2 km away
31. 1.76 km W of Cobb, CaliforniaTue, Apr 21, 9:27 PM PDT · 14408 days ago · 4 km deep · 0 km away
32. 1.84 km W of Moskowite Corner, CaliforniaWed, Apr 22, 7:05 AM PDT · 14408 days ago · 7 km deep · 64 km away
33. 1.76 km WSW of Cobb, CaliforniaWed, Apr 22, 2:34 PM PDT · 14407 days ago · 1 km deep · 2 km away
34. 1.87 km W of Cobb, CaliforniaThu, Apr 23, 2:51 AM PDT · 14407 days ago · 3 km deep · 1 km away
35. 1.74 km SSW of Cobb, CaliforniaThu, Apr 23, 8:35 AM PDT · 14407 days ago · -1 km deep · 6 km away
36. 2.15 km WNW of Cobb, CaliforniaThu, Apr 23, 10:14 PM PDT · 14406 days ago · 0 km deep · 1 km away
37. 1.65 km W of Cobb, CaliforniaFri, Apr 24, 1:11 AM PDT · 14406 days ago · 1 km deep · 1 km away
38. 1.65 km W of Cobb, CaliforniaFri, Apr 24, 4:01 AM PDT · 14406 days ago · -1 km deep · 1 km away
39. 2.47 km WSW of Cobb, CaliforniaFri, Apr 24, 5:00 AM PDT · 14406 days ago · 1 km deep · 2 km away
40. 2.2Northern CaliforniaFri, Apr 24, 5:02 AM PDT · 14406 days ago · 2 km deep · 4 km away
41. 1.56 km W of Cobb, CaliforniaFri, Apr 24, 1:03 PM PDT · 14405 days ago · 1 km deep · 1 km away
42. 1.75 km WNW of Cobb, CaliforniaFri, Apr 24, 2:07 PM PDT · 14405 days ago · 1 km deep · 2 km away
43. 1.85 km WNW of Cobb, CaliforniaSat, Apr 25, 6:51 AM PDT · 14405 days ago · 1 km deep · 1 km away
44. 2.85 km SW of Cobb, CaliforniaSat, Apr 25, 10:26 AM PDT · 14405 days ago · 2 km deep · 5 km away
45. 1.86 km W of Cobb, CaliforniaSat, Apr 25, 1:06 PM PDT · 14404 days ago · 3 km deep · 1 km away
46. 2.10 km SSW of Kelseyville, CaliforniaSun, Apr 26, 12:15 AM PDT · 14404 days ago · 4 km deep · 18 km away
47. 1.70 km SSW of Kelseyville, CaliforniaSun, Apr 26, 12:19 AM PDT · 14404 days ago · 4 km deep · 18 km away
48. 1.60 km N of Kelseyville, CaliforniaSun, Apr 26, 12:34 AM PDT · 14404 days ago · 4 km deep · 18 km away
49. 2.7Northern CaliforniaSun, Apr 26, 2:54 AM PDT · 14404 days ago · 4 km deep · 18 km away
50. 2.0Northern CaliforniaSun, Apr 26, 3:01 AM PDT · 14404 days ago · 4 km deep · 18 km away
51. 1.80 km N of Kelseyville, CaliforniaSun, Apr 26, 3:03 AM PDT · 14404 days ago · 3 km deep · 18 km away
52. 2.80 km WSW of Kelseyville, CaliforniaSun, Apr 26, 3:09 AM PDT · 14404 days ago · 3 km deep · 18 km away
53. 1.70 km WSW of Kelseyville, CaliforniaSun, Apr 26, 3:20 AM PDT · 14404 days ago · 4 km deep · 18 km away
54. 2.8Northern CaliforniaSun, Apr 26, 4:35 AM PDT · 14404 days ago · 4 km deep · 18 km away
55. 1.80 km N of Kelseyville, CaliforniaSun, Apr 26, 7:18 AM PDT · 14404 days ago · 3 km deep · 18 km away
56. 1.70 km NNW of Kelseyville, CaliforniaSun, Apr 26, 7:34 AM PDT · 14404 days ago · 2 km deep · 18 km away
57. 1.77 km WSW of Cobb, CaliforniaSun, Apr 26, 9:34 AM PDT · 14404 days ago · 3 km deep · 2 km away
58. 1.615 km ENE of Potter Valley, CaliforniaSun, Apr 26, 12:03 PM PDT · 14404 days ago · 6 km deep · 62 km away
59. 2.15 km WSW of Cobb, CaliforniaSun, Apr 26, 9:52 PM PDT · 14403 days ago · 4 km deep · 3 km away
60. 2.54 km SW of Cobb, CaliforniaMon, Apr 27, 12:34 AM PDT · 14403 days ago · 0 km deep · 4 km away

The first 60 of 175.

Before

1. 1.9Northern CaliforniaSun, Apr 12, 4:28 PM PDT · 14417 days ago · 0 km deep · 2 km away
2. 2.16 km W of Cobb, CaliforniaSun, Apr 12, 3:27 PM PDT · 14417 days ago · 4 km deep · 1 km away
3. 1.95 km W of Cobb, CaliforniaSun, Apr 12, 8:25 AM PDT · 14418 days ago · 1 km deep · 1 km away
4. 2.47 km W of Cobb, CaliforniaSat, Apr 11, 6:43 PM PDT · 14418 days ago · 1 km deep · 2 km away
5. 2.66 km W of Cobb, CaliforniaSat, Apr 11, 11:11 AM PDT · 14419 days ago · 3 km deep · 0 km away
6. 1.64 km WSW of Cobb, CaliforniaFri, Apr 10, 8:15 AM PDT · 14420 days ago · 2 km deep · 2 km away
7. 1.67 km ENE of Talmage, CaliforniaFri, Apr 10, 1:23 AM PDT · 14420 days ago · 4 km deep · 46 km away
8. 1.720 km ENE of Potter Valley, CaliforniaThu, Apr 9, 8:36 PM PDT · 14420 days ago · 7 km deep · 65 km away
9. 1.83 km SW of Cobb, CaliforniaThu, Apr 9, 4:36 PM PDT · 14420 days ago · 0 km deep · 5 km away
10. 1.76 km ENE of Willits, CaliforniaThu, Apr 9, 3:54 PM PDT · 14420 days ago · 3 km deep · 80 km away
11. 2.36 km ENE of Willits, CaliforniaThu, Apr 9, 3:53 PM PDT · 14420 days ago · 3 km deep · 80 km away
12. 2.56 km ENE of Willits, CaliforniaThu, Apr 9, 3:43 PM PDT · 14420 days ago · 3 km deep · 80 km away
13. 2.86 km ENE of Willits, CaliforniaThu, Apr 9, 3:42 PM PDT · 14420 days ago · 3 km deep · 80 km away
14. 1.56 km ENE of Willits, CaliforniaThu, Apr 9, 3:35 PM PDT · 14420 days ago · 4 km deep · 80 km away
15. 1.76 km ENE of Willits, CaliforniaThu, Apr 9, 3:33 PM PDT · 14420 days ago · 3 km deep · 80 km away
16. 2.96 km ENE of Willits, CaliforniaThu, Apr 9, 3:32 PM PDT · 14420 days ago · 4 km deep · 80 km away
17. 1.8Northern CaliforniaWed, Apr 8, 9:15 PM PDT · 14421 days ago · 6 km deep · 28 km away
18. 2.45 km WNW of Cobb, CaliforniaWed, Apr 8, 8:03 PM PDT · 14421 days ago · 1 km deep · 2 km away
19. 1.611 km S of Kelseyville, CaliforniaWed, Apr 8, 2:24 PM PDT · 14421 days ago · 0 km deep · 8 km away
20. 1.65 km SW of Cobb, CaliforniaTue, Apr 7, 6:30 PM PDT · 14422 days ago · 0 km deep · 5 km away

From the USGS Earthquake Hazards Program and its partner networks, event nc98450. Read Fri, Oct 2, 2026, 7:22 AM UTC.