M1.5 earthquake 8 km W of Cobb, California

Magnitude

1.5 (Md, duration), micro

Magnitude from

Northern California Seismic System

Local time

Sat, Mar 28, 1987, 4:47 PM PST

UTC

1987-03-29 00:47:39 UTC

Depth

1.1 km (0.7 mi), shallow

Epicenter

38.824° N, 122.820° W

Region

California

Tsunami flag

No

Status

Reviewed by a seismologist

Location uncertainty

About 0.4 km horizontally, 0.7 km in depth

Magnitude uncertainty

±0.14

Depth from

From location

Station coverage gap

96°

Stations used

8

• Cobb, CaliforniaPopulation 1,778. Forecast8 kmW
• Clearlake, CaliforniaPopulation 15,182. Forecast23 kmSW
• Santa Rosa, CaliforniaPopulation 178,127. Forecast44 kmNNW
• Los Angeles, CaliforniaPopulation 3,820,914. Forecast670 kmNW

After

1. 1.70 km SSW of Larkfield-Wikiup, CaliforniaSat, Mar 28, 4:51 PM PST · 14433 days ago · 0 km deep · 36 km away
2. 3.05 km WSW of Cobb, CaliforniaSat, Mar 28, 9:26 PM PST · 14433 days ago · 1 km deep · 4 km away
3. 2.16 km WSW of Cobb, CaliforniaSun, Mar 29, 4:08 AM PST · 14432 days ago · 0 km deep · 4 km away
4. 2.54 km WSW of Cobb, CaliforniaSun, Mar 29, 5:53 AM PST · 14432 days ago · -1 km deep · 5 km away
5. 2.06 km WSW of Cobb, CaliforniaSun, Mar 29, 7:37 AM PST · 14432 days ago · 0 km deep · 4 km away
6. 1.55 km SW of Cobb, CaliforniaSun, Mar 29, 12:52 PM PST · 14432 days ago · 2 km deep · 6 km away
7. 2.95 km SW of Cobb, CaliforniaSun, Mar 29, 10:20 PM PST · 14432 days ago · 3 km deep · 5 km away
8. 1.95 km SW of Cobb, CaliforniaTue, Mar 31, 1:09 AM PST · 14430 days ago · 1 km deep · 6 km away
9. 1.76 km W of Cobb, CaliforniaTue, Mar 31, 4:51 AM PST · 14430 days ago · 3 km deep · 2 km away
10. 2.615 km W of Guinda, CaliforniaTue, Mar 31, 2:55 PM PST · 14430 days ago · -1 km deep · 39 km away
11. 1.64 km ESE of Boonville, CATue, Mar 31, 8:46 PM PST · 14430 days ago · 4 km deep · 48 km away
12. 1.84 km ESE of Boonville, CaliforniaTue, Mar 31, 11:33 PM PST · 14430 days ago · 5 km deep · 47 km away
13. 1.63 km ESE of Boonville, CaliforniaWed, Apr 1, 6:21 AM PST · 14429 days ago · 5 km deep · 48 km away
14. 2.96 km WSW of Cobb, CaliforniaWed, Apr 1, 1:42 PM PST · 14429 days ago · 4 km deep · 3 km away
15. 2.06 km SW of Cobb, CaliforniaWed, Apr 1, 2:02 PM PST · 14429 days ago · -1 km deep · 6 km away
16. 1.77 km W of Cobb, CaliforniaThu, Apr 2, 1:40 AM PST · 14428 days ago · 0 km deep · 2 km away
17. 1.67 km W of Cobb, CaliforniaThu, Apr 2, 2:18 PM PST · 14428 days ago · 2 km deep · 1 km away
18. 1.613 km ESE of Hidden Valley Lake, CaliforniaThu, Apr 2, 3:40 PM PST · 14428 days ago · 3 km deep · 35 km away
19. 2.16 km W of Cobb, CaliforniaFri, Apr 3, 5:41 AM PST · 14427 days ago · 4 km deep · 2 km away
20. 1.93 km ESE of Kenwood, CaliforniaFri, Apr 3, 12:54 PM PST · 14427 days ago · 0 km deep · 55 km away
21. 1.79 km W of Cobb, CaliforniaFri, Apr 3, 10:53 PM PST · 14427 days ago · 0 km deep · 1 km away
22. 1.84 km WSW of Cobb, CaliforniaSat, Apr 4, 3:05 AM PST · 14426 days ago · 1 km deep · 5 km away
23. 1.68 km W of Cobb, CaliforniaSat, Apr 4, 8:31 AM PST · 14426 days ago · 1 km deep · 1 km away
24. 1.64 km WSW of Cobb, CaliforniaSat, Apr 4, 6:27 PM PST · 14426 days ago · 0 km deep · 5 km away
25. 1.66 km SW of Cobb, CaliforniaSun, Apr 5, 6:33 AM PDT · 14425 days ago · 1 km deep · 6 km away
26. 1.94 km WSW of Cobb, CaliforniaMon, Apr 6, 6:45 PM PDT · 14424 days ago · 2 km deep · 4 km away
27. 1.76 km W of Cobb, CaliforniaTue, Apr 7, 11:35 AM PDT · 14423 days ago · 3 km deep · 2 km away
28. 1.57 km WSW of Cobb, CaliforniaTue, Apr 7, 11:36 AM PDT · 14423 days ago · 3 km deep · 4 km away
29. 1.66 km W of Cobb, CaliforniaTue, Apr 7, 4:22 PM PDT · 14423 days ago · 3 km deep · 2 km away
30. 1.68 km WSW of Cobb, CaliforniaTue, Apr 7, 5:51 PM PDT · 14423 days ago · 3 km deep · 4 km away
31. 1.65 km SW of Cobb, CaliforniaTue, Apr 7, 6:30 PM PDT · 14423 days ago · 0 km deep · 6 km away
32. 1.611 km S of Kelseyville, CaliforniaWed, Apr 8, 2:24 PM PDT · 14422 days ago · 0 km deep · 7 km away
33. 2.45 km WNW of Cobb, CaliforniaWed, Apr 8, 8:03 PM PDT · 14422 days ago · 1 km deep · 3 km away
34. 1.8Northern CaliforniaWed, Apr 8, 9:15 PM PDT · 14422 days ago · 6 km deep · 28 km away
35. 2.96 km ENE of Willits, CaliforniaThu, Apr 9, 3:32 PM PDT · 14421 days ago · 4 km deep · 79 km away
36. 1.76 km ENE of Willits, CaliforniaThu, Apr 9, 3:33 PM PDT · 14421 days ago · 3 km deep · 79 km away
37. 1.56 km ENE of Willits, CaliforniaThu, Apr 9, 3:35 PM PDT · 14421 days ago · 4 km deep · 79 km away
38. 2.86 km ENE of Willits, CaliforniaThu, Apr 9, 3:42 PM PDT · 14421 days ago · 3 km deep · 78 km away
39. 2.56 km ENE of Willits, CaliforniaThu, Apr 9, 3:43 PM PDT · 14421 days ago · 3 km deep · 78 km away
40. 2.36 km ENE of Willits, CaliforniaThu, Apr 9, 3:53 PM PDT · 14421 days ago · 3 km deep · 79 km away
41. 1.76 km ENE of Willits, CaliforniaThu, Apr 9, 3:54 PM PDT · 14421 days ago · 3 km deep · 78 km away
42. 1.83 km SW of Cobb, CaliforniaThu, Apr 9, 4:36 PM PDT · 14421 days ago · 0 km deep · 7 km away
43. 1.720 km ENE of Potter Valley, CaliforniaThu, Apr 9, 8:36 PM PDT · 14421 days ago · 7 km deep · 64 km away
44. 1.67 km ENE of Talmage, CaliforniaFri, Apr 10, 1:23 AM PDT · 14420 days ago · 4 km deep · 44 km away
45. 1.64 km WSW of Cobb, CaliforniaFri, Apr 10, 8:15 AM PDT · 14420 days ago · 2 km deep · 4 km away
46. 2.66 km W of Cobb, CaliforniaSat, Apr 11, 11:11 AM PDT · 14419 days ago · 3 km deep · 2 km away
47. 2.47 km W of Cobb, CaliforniaSat, Apr 11, 6:43 PM PDT · 14419 days ago · 1 km deep · 1 km away
48. 1.95 km W of Cobb, CaliforniaSun, Apr 12, 8:25 AM PDT · 14418 days ago · 1 km deep · 3 km away
49. 2.16 km W of Cobb, CaliforniaSun, Apr 12, 3:27 PM PDT · 14418 days ago · 4 km deep · 2 km away
50. 1.9Northern CaliforniaSun, Apr 12, 4:28 PM PDT · 14418 days ago · 0 km deep · 3 km away
51. 1.86 km W of Cobb, CaliforniaSun, Apr 12, 9:35 PM PDT · 14418 days ago · 3 km deep · 2 km away
52. 1.62 km ESE of Calpella, CaliforniaMon, Apr 13, 2:36 AM PDT · 14417 days ago · 5 km deep · 54 km away
53. 1.97 km W of Cobb, CaliforniaMon, Apr 13, 4:48 AM PDT · 14417 days ago · 4 km deep · 1 km away
54. 1.87 km W of Cobb, CaliforniaMon, Apr 13, 5:31 AM PDT · 14417 days ago · 4 km deep · 1 km away
55. 2.06 km SW of Cobb, CaliforniaTue, Apr 14, 10:42 AM PDT · 14416 days ago · 3 km deep · 5 km away
56. 1.67 km W of Cobb, CaliforniaTue, Apr 14, 9:02 PM PDT · 14416 days ago · 3 km deep · 2 km away
57. 1.65 km SW of Cobb, CaliforniaTue, Apr 14, 10:39 PM PDT · 14416 days ago · 0 km deep · 6 km away
58. 1.66 km W of Cobb, CaliforniaTue, Apr 14, 11:45 PM PDT · 14416 days ago · 2 km deep · 2 km away
59. 1.87 km WSW of Cobb, CaliforniaWed, Apr 15, 3:43 AM PDT · 14415 days ago · 1 km deep · 3 km away
60. 1.95 km SSW of Cobb, CaliforniaWed, Apr 15, 6:27 AM PDT · 14415 days ago · 0 km deep · 7 km away

The first 60 of 171.

Before

1. 1.65 km WSW of Cobb, CaliforniaSat, Mar 28, 12:17 PM PST · 14433 days ago · 0 km deep · 5 km away
2. 1.77 km W of Cobb, CaliforniaSat, Mar 28, 9:45 AM PST · 14433 days ago · 3 km deep · 2 km away
3. 1.6Northern CaliforniaSat, Mar 28, 4:15 AM PST · 14433 days ago · 0 km deep · 5 km away
4. 1.86 km W of Cobb, CaliforniaFri, Mar 27, 9:49 PM PST · 14434 days ago · 3 km deep · 2 km away
5. 2.33 km NE of Anchor Bay, CaliforniaFri, Mar 27, 2:42 PM PST · 14434 days ago · 0 km deep · 63 km away
6. 1.59 km NW of Cobb, CaliforniaFri, Mar 27, 5:27 AM PST · 14434 days ago · 1 km deep · 7 km away
7. 1.81 km WSW of Hopland, CaliforniaThu, Mar 26, 9:46 PM PST · 14435 days ago · 0 km deep · 31 km away
8. 1.89 km ESE of Hidden Valley Lake, CaliforniaThu, Mar 26, 10:45 AM PST · 14435 days ago · 5 km deep · 32 km away
9. 1.75 km WNW of Cobb, CaliforniaThu, Mar 26, 10:37 AM PST · 14435 days ago · 1 km deep · 4 km away
10. 1.66 km W of Cobb, CaliforniaWed, Mar 25, 10:51 AM PST · 14436 days ago · 3 km deep · 2 km away
11. 1.76 km W of Cobb, CaliforniaWed, Mar 25, 2:09 AM PST · 14436 days ago · 1 km deep · 2 km away
12. 2.08 km W of Cobb, CaliforniaWed, Mar 25, 2:00 AM PST · 14436 days ago · 2 km deep · 1 km away
13. 1.88 km W of Cobb, CaliforniaWed, Mar 25, 12:43 AM PST · 14436 days ago · 3 km deep · 2 km away
14. 2.37 km WSW of Cobb, CaliforniaTue, Mar 24, 6:05 AM PST · 14437 days ago · 1 km deep · 3 km away
15. 1.74 km W of Cobb, CaliforniaMon, Mar 23, 1:48 PM PST · 14438 days ago · 0 km deep · 4 km away
16. 3.17 km WSW of Cobb, CaliforniaMon, Mar 23, 8:44 AM PST · 14438 days ago · 1 km deep · 3 km away
17. 1.610 km W of Cobb, CaliforniaMon, Mar 23, 3:12 AM PST · 14438 days ago · 4 km deep · 2 km away
18. 2.16 km SW of Cobb, CaliforniaMon, Mar 23, 1:30 AM PST · 14438 days ago · 0 km deep · 6 km away
19. 1.65 km W of Cobb, CaliforniaSun, Mar 22, 10:08 PM PST · 14439 days ago · 1 km deep · 3 km away
20. 1.65 km SW of Cobb, CaliforniaSun, Mar 22, 8:37 PM PST · 14439 days ago · 3 km deep · 7 km away

From the USGS Earthquake Hazards Program and its partner networks, event nc1148637. Read Fri, Oct 2, 2026, 7:49 PM UTC.