M1.9 earthquake 7 km W of Cobb, California

Magnitude

1.9 (md), micro

Local time

Tue, Sep 22, 1987, 7:59 PM PDT

UTC

1987-09-23 02:59:55 UTC

Depth

3.1 km (1.9 mi), shallow

Epicenter

38.812° N, 122.812° W

Region

California

Tsunami flag

No

Status

Reviewed by a seismologist

Location uncertainty

About 0.3 km horizontally, 0.5 km in depth

Magnitude uncertainty

±0.08

Depth from

From location

Station coverage gap

111°

Stations used

14

• Cobb, CaliforniaPopulation 1,778. Forecast8 kmW
• Clearlake, CaliforniaPopulation 15,182. Forecast23 kmSW
• Santa Rosa, CaliforniaPopulation 178,127. Forecast42 kmNNW
• Los Angeles, CaliforniaPopulation 3,820,914. Forecast668 kmNW

After

1. 2.06 km WSW of Cobb, CaliforniaTue, Sep 22, 8:15 PM PDT · 14251 days ago · 1 km deep · 1 km away
2. 2.77 km WSW of Cobb, CaliforniaWed, Sep 23, 1:25 AM PDT · 14251 days ago · 3 km deep · 1 km away
3. 1.78 km W of Cobb, CaliforniaWed, Sep 23, 10:54 PM PDT · 14250 days ago · 1 km deep · 1 km away
4. 1.711 km W of Cobb, CaliforniaThu, Sep 24, 5:12 AM PDT · 14250 days ago · 4 km deep · 4 km away
5. 2.15 km SW of Cobb, CaliforniaThu, Sep 24, 5:49 AM PDT · 14250 days ago · 0 km deep · 6 km away
6. 3.05 km SW of Cobb, CaliforniaThu, Sep 24, 5:50 AM PDT · 14250 days ago · 0 km deep · 6 km away
7. 1.86 km WSW of Cobb, CaliforniaThu, Sep 24, 10:47 AM PDT · 14249 days ago · 0 km deep · 2 km away
8. 1.76 km SW of Cobb, CaliforniaThu, Sep 24, 4:09 PM PDT · 14249 days ago · 0 km deep · 5 km away
9. 1.65 km WSW of Cobb, CaliforniaFri, Sep 25, 2:34 PM PDT · 14248 days ago · 0 km deep · 3 km away
10. 2.25 km SSW of Cobb, CaliforniaFri, Sep 25, 5:39 PM PDT · 14248 days ago · 12 km deep · 6 km away
11. 2.55 km W of Cobb, CaliforniaFri, Sep 25, 7:39 PM PDT · 14248 days ago · 3 km deep · 2 km away
12. 2.97 km WSW of Cobb, CaliforniaSat, Sep 26, 7:55 AM PDT · 14247 days ago · 1 km deep · 1 km away
13. 1.77 km WSW of Cobb, CaliforniaSat, Sep 26, 9:50 AM PDT · 14247 days ago · 1 km deep · 2 km away
14. 1.86 km WSW of Cobb, CaliforniaSun, Sep 27, 12:18 AM PDT · 14247 days ago · 0 km deep · 2 km away
15. 2.62 km ESE of Mendocino, CaliforniaSun, Sep 27, 1:26 AM PDT · 14247 days ago · 26 km deep · 99 km away
16. 1.54 km WSW of Cobb, CaliforniaSun, Sep 27, 6:39 AM PDT · 14246 days ago · 0 km deep · 4 km away
17. 3.05 km SW of Cobb, CaliforniaTue, Sep 29, 12:04 AM PDT · 14245 days ago · 0 km deep · 4 km away
18. 3.25 km SW of Cobb, CaliforniaTue, Sep 29, 12:04 AM PDT · 14245 days ago · 0 km deep · 4 km away
19. 1.64 km N of Clear Lake Riviera, CaliforniaTue, Sep 29, 5:18 AM PDT · 14245 days ago · 1 km deep · 22 km away
20. 2.011 km W of Cobb, CaliforniaTue, Sep 29, 9:11 AM PDT · 14244 days ago · 2 km deep · 4 km away
21. 2.06 km W of Cobb, CaliforniaTue, Sep 29, 6:59 PM PDT · 14244 days ago · 3 km deep · 2 km away
22. 1.710 km W of Cobb, CaliforniaTue, Sep 29, 8:26 PM PDT · 14244 days ago · 1 km deep · 4 km away
23. 1.57 km W of Cobb, CaliforniaThu, Oct 1, 12:32 AM PDT · 14243 days ago · 3 km deep · 0 km away
24. 1.86 km WSW of Cobb, CaliforniaThu, Oct 1, 11:17 AM PDT · 14242 days ago · 4 km deep · 2 km away
25. 1.96 km S of Clear Lake Riviera, CaliforniaThu, Oct 1, 4:13 PM PDT · 14242 days ago · -1 km deep · 12 km away
26. 2.19 km W of Cobb, CaliforniaThu, Oct 1, 4:51 PM PDT · 14242 days ago · 0 km deep · 2 km away
27. 1.75 km WSW of Cobb, CaliforniaFri, Oct 2, 3:04 AM PDT · 14242 days ago · -1 km deep · 3 km away
28. 1.54 km SW of Kenwood, CaliforniaFri, Oct 2, 12:47 PM PDT · 14241 days ago · 2 km deep · 51 km away
29. 1.85 km W of Cobb, CaliforniaSat, Oct 3, 6:14 AM PDT · 14240 days ago · 1 km deep · 2 km away
30. 1.77 km W of Cobb, CaliforniaSat, Oct 3, 7:59 AM PDT · 14240 days ago · 0 km deep · 2 km away
31. 2.112 km NE of Philo, CaliforniaSat, Oct 3, 1:19 PM PDT · 14240 days ago · -1 km deep · 61 km away
32. 1.57 km W of Cobb, CaliforniaSun, Oct 4, 2:15 AM PDT · 14240 days ago · 3 km deep · 1 km away
33. 1.74 km WSW of Cobb, CaliforniaSun, Oct 4, 8:50 AM PDT · 14239 days ago · 2 km deep · 4 km away
34. 1.57 km W of Cobb, CaliforniaSun, Oct 4, 7:17 PM PDT · 14239 days ago · 0 km deep · 2 km away
35. 1.7Northern CaliforniaMon, Oct 5, 6:07 AM PDT · 14238 days ago · 2 km deep · 51 km away
36. 1.56 km WNW of Cobb, CaliforniaMon, Oct 5, 3:23 PM PDT · 14238 days ago · 0 km deep · 3 km away
37. 1.71 km ENE of American Canyon, CaliforniaTue, Oct 6, 6:18 AM PDT · 14237 days ago · 9 km deep · 86 km away
38. 3.16 km W of Cobb, CaliforniaTue, Oct 6, 9:30 AM PDT · 14237 days ago · 3 km deep · 2 km away
39. 1.611 km WNW of Calistoga, CaliforniaTue, Oct 6, 3:26 PM PDT · 14237 days ago · 7 km deep · 24 km away
40. 1.72 km NNW of Clear Lake Riviera, CaliforniaTue, Oct 6, 9:32 PM PDT · 14237 days ago · 8 km deep · 19 km away
41. 2.04 km SW of Hopland, CaliforniaFri, Oct 9, 1:24 AM PDT · 14235 days ago · 4 km deep · 34 km away
42. 3.16 km W of Cobb, CaliforniaFri, Oct 9, 2:05 AM PDT · 14235 days ago · 4 km deep · 2 km away
43. 1.86 km W of Cobb, CaliforniaFri, Oct 9, 2:07 AM PDT · 14235 days ago · 3 km deep · 1 km away
44. 1.54 km WSW of Cobb, CaliforniaFri, Oct 9, 9:01 AM PDT · 14234 days ago · 1 km deep · 3 km away
45. 1.56 km W of Cobb, CaliforniaFri, Oct 9, 5:49 PM PDT · 14234 days ago · 3 km deep · 2 km away
46. 2.16 km SW of Cobb, CaliforniaSat, Oct 10, 4:18 AM PDT · 14234 days ago · 1 km deep · 5 km away
47. 1.67 km W of Cobb, CaliforniaSat, Oct 10, 5:18 AM PDT · 14234 days ago · 1 km deep · 2 km away
48. 1.85 km WSW of Cobb, CaliforniaSat, Oct 10, 7:36 AM PDT · 14233 days ago · 0 km deep · 3 km away
49. 1.94 km NW of Philo, CaliforniaSat, Oct 10, 2:33 PM PDT · 14233 days ago · -1 km deep · 66 km away
50. 1.59 km WSW of Cobb, CaliforniaSat, Oct 10, 6:43 PM PDT · 14233 days ago · 1 km deep · 2 km away
51. 2.3Northern CaliforniaSun, Oct 11, 3:42 AM PDT · 14233 days ago · 1 km deep · 2 km away
52. 2.37 km NNE of Hopland, CaliforniaSun, Oct 11, 7:08 AM PDT · 14232 days ago · 1 km deep · 33 km away
53. 1.96 km W of Cobb, CaliforniaSun, Oct 11, 8:37 AM PDT · 14232 days ago · 3 km deep · 2 km away
54. 1.66 km W of Cobb, CaliforniaMon, Oct 12, 12:36 AM PDT · 14232 days ago · 3 km deep · 1 km away
55. 1.85 km W of Cobb, CaliforniaMon, Oct 12, 12:38 AM PDT · 14232 days ago · 2 km deep · 2 km away
56. 2.55 km W of Cobb, CaliforniaMon, Oct 12, 12:40 AM PDT · 14232 days ago · 2 km deep · 2 km away
57. 1.68 km W of Cobb, CaliforniaMon, Oct 12, 6:37 AM PDT · 14231 days ago · 3 km deep · 1 km away
58. 1.66 km SW of Cobb, CaliforniaMon, Oct 12, 4:05 PM PDT · 14231 days ago · 0 km deep · 5 km away
59. 2.24 km S of Cobb, CaliforniaMon, Oct 12, 4:41 PM PDT · 14231 days ago · 2 km deep · 9 km away
60. 2.28 km WSW of Cobb, CaliforniaMon, Oct 12, 9:55 PM PDT · 14231 days ago · 0 km deep · 1 km away

The first 60 of 161.

Before

1. 1.74 km SE of Clear Lake Riviera, CaliforniaTue, Sep 22, 4:17 PM PDT · 14251 days ago · 7 km deep · 17 km away
2. 2.05 km WSW of Cobb, CaliforniaTue, Sep 22, 3:20 PM PDT · 14251 days ago · 1 km deep · 3 km away
3. 1.77 km WSW of Cobb, CaliforniaMon, Sep 21, 7:00 PM PDT · 14252 days ago · 2 km deep · 1 km away
4. 1.55 km WNW of Cobb, CaliforniaSun, Sep 20, 10:18 PM PDT · 14253 days ago · 1 km deep · 3 km away
5. 1.77 km W of Cobb, CaliforniaSun, Sep 20, 11:26 AM PDT · 14253 days ago · -1 km deep · 2 km away
6. 3.44 km W of Cobb, CaliforniaSun, Sep 20, 11:23 AM PDT · 14253 days ago · 2 km deep · 4 km away
7. 1.97 km WSW of Cobb, CaliforniaSun, Sep 20, 8:56 AM PDT · 14253 days ago · 1 km deep · 1 km away
8. 1.93 km NNW of Cloverdale, CaliforniaSat, Sep 19, 4:37 PM PDT · 14254 days ago · -1 km deep · 19 km away
9. 2.58 km W of Cobb, CaliforniaSat, Sep 19, 2:19 AM PDT · 14255 days ago · 1 km deep · 1 km away
10. 1.98 km W of Cobb, CaliforniaSat, Sep 19, 2:06 AM PDT · 14255 days ago · -1 km deep · 2 km away
11. 2.46 km W of Cobb, CaliforniaFri, Sep 18, 8:39 PM PDT · 14255 days ago · 2 km deep · 1 km away
12. 2.55 km SW of Cobb, CaliforniaFri, Sep 18, 7:50 PM PDT · 14255 days ago · 1 km deep · 4 km away
13. 1.76 km W of Cobb, CaliforniaFri, Sep 18, 11:19 AM PDT · 14255 days ago · 1 km deep · 2 km away
14. 2.018 km NE of Potter Valley, CaliforniaFri, Sep 18, 6:57 AM PDT · 14255 days ago · 6 km deep · 73 km away
15. 1.65 km SW of Cobb, CaliforniaThu, Sep 17, 6:24 AM PDT · 14256 days ago · -1 km deep · 6 km away
16. 1.617 km N of Upper Lake, CaliforniaThu, Sep 17, 5:10 AM PDT · 14257 days ago · 1 km deep · 57 km away
17. 1.52 km NNE of Cloverdale, CaliforniaWed, Sep 16, 5:17 PM PDT · 14257 days ago · 0 km deep · 17 km away
18. 1.74 km W of Cobb, CaliforniaWed, Sep 16, 2:46 PM PDT · 14257 days ago · 0 km deep · 4 km away
19. 1.94 km W of Cobb, CaliforniaWed, Sep 16, 2:15 PM PDT · 14257 days ago · 1 km deep · 3 km away
20. 1.69 km WSW of Cobb, CaliforniaWed, Sep 16, 12:13 PM PDT · 14257 days ago · 0 km deep · 1 km away

From the USGS Earthquake Hazards Program and its partner networks, event nc106213. Read Tue, Sep 29, 2026, 12:23 AM UTC.