M1.8 earthquake 4 km SW of Cobb, California

Magnitude

1.8 (Md, duration), micro

Magnitude from

Northern California Seismic System

Local time

Fri, Aug 14, 1987, 5:35 PM PDT

UTC

1987-08-15 00:35:35 UTC

Depth

0.3 km (0.2 mi), shallow

Epicenter

38.793° N, 122.765° W

Region

California

Tsunami flag

No

Status

Reviewed by a seismologist

Location uncertainty

About 0.2 km horizontally, 0.6 km in depth

Magnitude uncertainty

±0.14

Depth from

From location

Station coverage gap

53°

Stations used

15

• Cobb, CaliforniaPopulation 1,778. Forecast5 kmSW
• Clearlake, CaliforniaPopulation 15,182. Forecast22 kmSSW
• Santa Rosa, CaliforniaPopulation 178,127. Forecast39 kmN
• Los Angeles, CaliforniaPopulation 3,820,914. Forecast664 kmNW

After

1. 1.87 km W of Cobb, CaliforniaFri, Aug 14, 7:48 PM PDT · 14293 days ago · 1 km deep · 6 km away
2. 1.87 km WSW of Cobb, CaliforniaSat, Aug 15, 4:55 AM PDT · 14293 days ago · 2 km deep · 3 km away
3. 1.97 km WSW of Cobb, CaliforniaSat, Aug 15, 7:58 PM PDT · 14292 days ago · 1 km deep · 4 km away
4. 1.72 km SSW of Clearlake, CaliforniaSun, Aug 16, 6:37 AM PDT · 14292 days ago · 3 km deep · 19 km away
5. 1.8Northern CaliforniaSun, Aug 16, 12:20 PM PDT · 14291 days ago · 1 km deep · 5 km away
6. 1.59 km ESE of Hidden Valley Lake, CaliforniaSun, Aug 16, 1:02 PM PDT · 14291 days ago · 5 km deep · 27 km away
7. 1.91 km W of Green Valley, CaliforniaSun, Aug 16, 3:59 PM PDT · 14291 days ago · 10 km deep · 79 km away
8. 2.15 km SW of Cobb, CaliforniaMon, Aug 17, 2:46 AM PDT · 14291 days ago · 2 km deep · 1 km away
9. 2.06 km W of Cobb, CaliforniaMon, Aug 17, 6:38 AM PDT · 14291 days ago · 4 km deep · 5 km away
10. 1.65 km W of Cobb, CaliforniaMon, Aug 17, 6:58 AM PDT · 14291 days ago · 1 km deep · 4 km away
11. 1.63 km NNW of Cloverdale, CaliforniaMon, Aug 17, 6:05 PM PDT · 14290 days ago · -1 km deep · 23 km away
12. 1.75 km WSW of Cobb, CaliforniaMon, Aug 17, 11:11 PM PDT · 14290 days ago · 0 km deep · 1 km away
13. 1.811 km SSW of Cloverdale, CaliforniaTue, Aug 18, 5:46 AM PDT · 14290 days ago · 4 km deep · 29 km away
14. 1.64 km SW of Cobb, CaliforniaTue, Aug 18, 11:26 AM PDT · 14289 days ago · 0 km deep · 1 km away
15. 2.58 km W of Cobb, CaliforniaWed, Aug 19, 2:45 AM PDT · 14289 days ago · 0 km deep · 6 km away
16. 2.110 km ENE of Lucerne, CaliforniaWed, Aug 19, 3:19 AM PDT · 14289 days ago · 24 km deep · 39 km away
17. 2.67 km W of Cobb, CaliforniaWed, Aug 19, 6:13 AM PDT · 14289 days ago · 3 km deep · 5 km away
18. 2.16 km W of Cobb, CaliforniaWed, Aug 19, 7:13 PM PDT · 14288 days ago · 3 km deep · 4 km away
19. 1.63 km NNW of Cloverdale, CaliforniaThu, Aug 20, 5:52 PM PDT · 14287 days ago · 2 km deep · 24 km away
20. 1.96 km W of Cobb, CaliforniaThu, Aug 20, 9:50 PM PDT · 14287 days ago · -1 km deep · 5 km away
21. 1.86 km W of Cobb, CaliforniaThu, Aug 20, 9:59 PM PDT · 14287 days ago · 0 km deep · 5 km away
22. 1.96 km W of Cobb, CaliforniaThu, Aug 20, 9:59 PM PDT · 14287 days ago · 0 km deep · 4 km away
23. 1.66 km W of Cobb, CaliforniaFri, Aug 21, 1:55 AM PDT · 14287 days ago · 1 km deep · 5 km away
24. 1.75 km W of Cobb, CaliforniaFri, Aug 21, 2:31 AM PDT · 14287 days ago · 0 km deep · 5 km away
25. 1.86 km W of Cobb, CaliforniaSat, Aug 22, 7:13 AM PDT · 14286 days ago · 3 km deep · 4 km away
26. 2.16 km W of Cobb, CaliforniaSat, Aug 22, 7:33 AM PDT · 14286 days ago · 3 km deep · 4 km away
27. 1.65 km WNW of Cobb, CaliforniaSat, Aug 22, 10:58 AM PDT · 14285 days ago · 1 km deep · 5 km away
28. 2.9Northern CaliforniaSat, Aug 22, 11:03 AM PDT · 14285 days ago · 2 km deep · 7 km away
29. 2.27 km WSW of Cobb, CaliforniaSat, Aug 22, 11:16 PM PDT · 14285 days ago · 0 km deep · 4 km away
30. 1.87 km W of Cobb, CaliforniaSun, Aug 23, 1:54 AM PDT · 14285 days ago · 3 km deep · 5 km away
31. 2.06 km WSW of Cobb, CaliforniaSun, Aug 23, 2:53 AM PDT · 14285 days ago · 1 km deep · 3 km away
32. 2.14 km W of Cobb, CaliforniaSun, Aug 23, 4:28 AM PDT · 14285 days ago · 1 km deep · 4 km away
33. 2.06 km WSW of Cobb, CaliforniaSun, Aug 23, 9:05 AM PDT · 14285 days ago · 1 km deep · 3 km away
34. 1.711 km WNW of Redwood Valley, CaliforniaSun, Aug 23, 10:24 AM PDT · 14285 days ago · 6 km deep · 75 km away
35. 2.17 km WSW of Cobb, CaliforniaSun, Aug 23, 8:23 PM PDT · 14284 days ago · 1 km deep · 4 km away
36. 2.67 km W of Cobb, CaliforniaMon, Aug 24, 1:10 AM PDT · 14284 days ago · 0 km deep · 6 km away
37. 1.88 km NW of Redwood Valley, CaliforniaMon, Aug 24, 6:59 AM PDT · 14284 days ago · 2 km deep · 73 km away
38. 1.611 km N of Brooktrails, CaliforniaMon, Aug 24, 8:43 PM PDT · 14283 days ago · 6 km deep · 100 km away
39. 1.64 km S of Cobb, CaliforniaMon, Aug 24, 11:51 PM PDT · 14283 days ago · -1 km deep · 3 km away
40. 2.45 km SW of Cobb, CaliforniaTue, Aug 25, 3:50 AM PDT · 14283 days ago · 0 km deep · 1 km away
41. 1.82 km WNW of Brooktrails, CaliforniaTue, Aug 25, 5:54 AM PDT · 14283 days ago · 2 km deep · 92 km away
42. 1.86 km NE of Brooktrails, CaliforniaTue, Aug 25, 6:22 AM PDT · 14283 days ago · 5 km deep · 92 km away
43. 1.79 km W of Cobb, CaliforniaWed, Aug 26, 11:09 AM PDT · 14281 days ago · -1 km deep · 6 km away
44. 2.16 km E of Hidden Valley Lake, CaliforniaThu, Aug 27, 7:16 AM PDT · 14281 days ago · 14 km deep · 25 km away
45. 2.18 km W of Cobb, CaliforniaThu, Aug 27, 8:53 AM PDT · 14281 days ago · 0 km deep · 6 km away
46. 1.88 km W of Cobb, CaliforniaThu, Aug 27, 8:54 AM PDT · 14281 days ago · 0 km deep · 6 km away
47. 2.38 km WSW of Cobb, CaliforniaThu, Aug 27, 11:54 AM PDT · 14280 days ago · 2 km deep · 4 km away
48. 2.56 km W of Cobb, CaliforniaFri, Aug 28, 1:27 PM PDT · 14279 days ago · 1 km deep · 4 km away
49. 2.26 km W of Cobb, CaliforniaFri, Aug 28, 4:53 PM PDT · 14279 days ago · 3 km deep · 4 km away
50. 1.7Northern CaliforniaSat, Aug 29, 5:00 AM PDT · 14279 days ago · 0 km deep · 6 km away
51. 2.37 km WSW of Cobb, CaliforniaSat, Aug 29, 6:24 AM PDT · 14279 days ago · 1 km deep · 4 km away
52. 2.028 km NNE of Potter Valley, CaliforniaSun, Aug 30, 6:16 AM PDT · 14278 days ago · 13 km deep · 87 km away
53. 2.05 km WNW of Cobb, CaliforniaSun, Aug 30, 10:24 AM PDT · 14278 days ago · 2 km deep · 5 km away
54. 1.65 km SSW of Cobb, CaliforniaSun, Aug 30, 12:42 PM PDT · 14277 days ago · 0 km deep · 1 km away
55. 2.14 km W of Cobb, CaliforniaSun, Aug 30, 2:46 PM PDT · 14277 days ago · 0 km deep · 3 km away
56. 1.97 km W of Cobb, CaliforniaSun, Aug 30, 5:06 PM PDT · 14277 days ago · 3 km deep · 5 km away
57. 2.05 km SSE of Kelseyville, CaliforniaTue, Sep 1, 9:10 AM PDT · 14276 days ago · 0 km deep · 16 km away
58. 3.08 km W of Cobb, CaliforniaTue, Sep 1, 9:41 AM PDT · 14276 days ago · 1 km deep · 5 km away
59. 2.06 km NNE of Penngrove, CaliforniaTue, Sep 1, 1:55 PM PDT · 14275 days ago · 4 km deep · 51 km away
60. 1.76 km W of Cobb, CaliforniaTue, Sep 1, 8:20 PM PDT · 14275 days ago · 1 km deep · 5 km away

The first 60 of 166.

Before

1. 2.27 km W of Cobb, CaliforniaFri, Aug 14, 12:09 PM PDT · 14293 days ago · 4 km deep · 5 km away
2. 1.74 km W of Cobb, CaliforniaFri, Aug 14, 9:28 AM PDT · 14294 days ago · 1 km deep · 3 km away
3. 1.55 km WNW of Cobb, CaliforniaThu, Aug 13, 10:16 PM PDT · 14294 days ago · 1 km deep · 5 km away
4. 1.56 km W of Cobb, CaliforniaThu, Aug 13, 5:25 PM PDT · 14294 days ago · 2 km deep · 4 km away
5. 1.79 km SE of Boonville, CaliforniaThu, Aug 13, 12:05 PM PDT · 14294 days ago · 7 km deep · 48 km away
6. 1.87 km WSW of Cobb, CaliforniaThu, Aug 13, 12:03 PM PDT · 14294 days ago · 1 km deep · 3 km away
7. 1.57 km WSW of Cobb, CaliforniaThu, Aug 13, 6:23 AM PDT · 14295 days ago · 3 km deep · 3 km away
8. 1.66 km SW of Cobb, CaliforniaWed, Aug 12, 6:47 PM PDT · 14295 days ago · 0 km deep · 1 km away
9. 1.83 km N of Cloverdale, CaliforniaWed, Aug 12, 5:48 PM PDT · 14295 days ago · 0 km deep · 23 km away
10. 1.66 km W of Cobb, CaliforniaWed, Aug 12, 4:34 PM PDT · 14295 days ago · 2 km deep · 4 km away
11. 1.86 km WSW of Cobb, CaliforniaWed, Aug 12, 10:59 AM PDT · 14295 days ago · 1 km deep · 3 km away
12. 1.86 km WSW of Cobb, CaliforniaWed, Aug 12, 10:48 AM PDT · 14295 days ago · 0 km deep · 3 km away
13. 2.010 km SE of Willits, CaliforniaWed, Aug 12, 6:47 AM PDT · 14296 days ago · 0 km deep · 75 km away
14. 1.86 km SW of Cobb, CaliforniaWed, Aug 12, 1:57 AM PDT · 14296 days ago · 0 km deep · 1 km away
15. 1.67 km W of Cobb, CaliforniaTue, Aug 11, 12:16 PM PDT · 14296 days ago · 1 km deep · 5 km away
16. 1.75 km W of Cobb, CaliforniaMon, Aug 10, 10:10 PM PDT · 14297 days ago · -1 km deep · 5 km away
17. 1.86 km SW of Cobb, CaliforniaMon, Aug 10, 9:42 PM PDT · 14297 days ago · 1 km deep · 1 km away
18. 1.86 km SW of Cobb, CaliforniaMon, Aug 10, 7:28 PM PDT · 14297 days ago · 1 km deep · 1 km away
19. 1.66 km W of Cobb, CaliforniaMon, Aug 10, 12:45 PM PDT · 14297 days ago · 3 km deep · 4 km away
20. 1.64 km WSW of Cobb, CaliforniaMon, Aug 10, 10:01 AM PDT · 14298 days ago · 1 km deep · 1 km away

From the USGS Earthquake Hazards Program and its partner networks, event nc104598. Read Fri, Oct 2, 2026, 5:01 AM UTC.