M2.1 earthquake 6 km WSW of Cobb, California

Magnitude

2.1 (Md, duration), micro

Magnitude from

Northern California Seismic System

Local time

Tue, Aug 23, 1983, 1:44 PM PDT

UTC

1983-08-23 20:44:25 UTC

Depth

-0.5 km (-0.3 mi), shallow

Epicenter

38.800° 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

±0.11

Depth from

From location

Station coverage gap

34°

Stations used

33

• Cobb, CaliforniaPopulation 1,778. Forecast7 kmWSW
• Healdsburg, CaliforniaPopulation 11,742. Forecast22 kmNNE
• Santa Rosa, CaliforniaPopulation 178,127. Forecast41 kmN
• Los Angeles, CaliforniaPopulation 3,820,914. Forecast667 kmNW

After

1. 1.67 km WSW of Cobb, CaliforniaTue, Aug 23, 1:53 PM PDT · 15745 days ago · -1 km deep · 1 km away
2. 1.7Northern CaliforniaTue, Aug 23, 2:41 PM PDT · 15745 days ago · -1 km deep · 1 km away
3. 1.69 km WSW of Cobb, CaliforniaTue, Aug 23, 2:58 PM PDT · 15745 days ago · 1 km deep · 3 km away
4. 1.57 km WSW of Cobb, CaliforniaWed, Aug 24, 12:38 AM PDT · 15744 days ago · 2 km deep · 1 km away
5. 1.626 km N of Potter Valley, CaliforniaWed, Aug 24, 1:25 PM PDT · 15744 days ago · -1 km deep · 88 km away
6. 1.87 km ENE of Brooktrails, CaliforniaWed, Aug 24, 4:37 PM PDT · 15744 days ago · 8 km deep · 86 km away
7. 1.75 km SW of Oakville, CaliforniaWed, Aug 24, 10:14 PM PDT · 15744 days ago · 4 km deep · 53 km away
8. 2.07 km W of Cobb, CaliforniaThu, Aug 25, 8:58 AM PDT · 15743 days ago · 3 km deep · 2 km away
9. 3.07 km WSW of Cobb, CaliforniaThu, Aug 25, 3:23 PM PDT · 15743 days ago · 1 km deep · 1 km away
10. 1.76 km S of Cobb, CaliforniaThu, Aug 25, 4:21 PM PDT · 15743 days ago · 0 km deep · 8 km away
11. 1.76 km ESE of Calpella, CaliforniaThu, Aug 25, 4:49 PM PDT · 15743 days ago · -1 km deep · 55 km away
12. 1.66 km W of Cobb, CaliforniaThu, Aug 25, 9:58 PM PDT · 15743 days ago · 2 km deep · 2 km away
13. 1.64 km S of Cobb, CaliforniaThu, Aug 25, 10:38 PM PDT · 15742 days ago · 0 km deep · 6 km away
14. 2.37 km WSW of Cobb, CaliforniaFri, Aug 26, 2:25 AM PDT · 15742 days ago · 0 km deep · 1 km away
15. 1.87 km W of Cobb, CaliforniaFri, Aug 26, 4:10 AM PDT · 15742 days ago · 3 km deep · 2 km away
16. 1.65 km SSW of Cobb, CaliforniaFri, Aug 26, 1:47 PM PDT · 15742 days ago · 0 km deep · 4 km away
17. 1.66 km WSW of Cobb, CaliforniaSat, Aug 27, 6:20 PM PDT · 15741 days ago · 1 km deep · 1 km away
18. 1.66 km W of Cobb, CaliforniaSun, Aug 28, 6:34 PM PDT · 15740 days ago · 1 km deep · 1 km away
19. 2.94 km ENE of Hopland, CaliforniaSun, Aug 28, 6:45 PM PDT · 15740 days ago · 6 km deep · 31 km away
20. 1.96 km WSW of Cobb, CaliforniaMon, Aug 29, 1:48 AM PDT · 15739 days ago · 0 km deep · 0 km away
21. 1.84 km S of Cobb, CaliforniaTue, Aug 30, 12:36 AM PDT · 15738 days ago · 1 km deep · 6 km away
22. 1.74 km S of Cobb, CaliforniaTue, Aug 30, 12:36 AM PDT · 15738 days ago · 1 km deep · 7 km away
23. 1.73 km S of Cobb, CaliforniaTue, Aug 30, 12:55 AM PDT · 15738 days ago · 0 km deep · 6 km away
24. 1.54 km S of Cobb, CaliforniaTue, Aug 30, 11:54 AM PDT · 15738 days ago · 1 km deep · 6 km away
25. 1.55 km SSW of Cobb, CaliforniaTue, Aug 30, 5:25 PM PDT · 15738 days ago · 0 km deep · 4 km away
26. 2.25 km E of Lower Lake, CaliforniaTue, Aug 30, 9:07 PM PDT · 15738 days ago · 5 km deep · 25 km away
27. 1.92 km ENE of Calpella, CaliforniaWed, Aug 31, 1:48 AM PDT · 15737 days ago · 8 km deep · 59 km away
28. 2.17 km W of Cobb, CaliforniaWed, Aug 31, 3:21 AM PDT · 15737 days ago · 3 km deep · 3 km away
29. 2.012 km WSW of Hopland, CaliforniaWed, Aug 31, 1:11 PM PDT · 15737 days ago · 0 km deep · 42 km away
30. 1.69 km WSW of Cobb, CaliforniaWed, Aug 31, 3:56 PM PDT · 15737 days ago · 2 km deep · 3 km away
31. 1.65 km SSW of Cobb, CaliforniaWed, Aug 31, 4:49 PM PDT · 15737 days ago · -1 km deep · 5 km away
32. 1.7Northern CaliforniaWed, Aug 31, 8:37 PM PDT · 15737 days ago · 13 km deep · 83 km away
33. 1.69 km SW of Clear Lake Riviera, CaliforniaThu, Sep 1, 7:15 AM PDT · 15736 days ago · 9 km deep · 10 km away
34. 1.610 km SSW of Comptche, CaliforniaThu, Sep 1, 2:00 PM PDT · 15736 days ago · 3 km deep · 82 km away
35. 1.88 km W of Cobb, CaliforniaThu, Sep 1, 3:30 PM PDT · 15736 days ago · 0 km deep · 3 km away
36. 1.57 km W of Cobb, CaliforniaFri, Sep 2, 10:59 AM PDT · 15735 days ago · 3 km deep · 2 km away
37. 2.01 km ENE of Middletown, CaliforniaFri, Sep 2, 4:14 PM PDT · 15735 days ago · 55 km deep · 18 km away
38. 1.58 km WSW of Cobb, CaliforniaFri, Sep 2, 7:19 PM PDT · 15735 days ago · 1 km deep · 2 km away
39. 1.56 km W of Cobb, CaliforniaSat, Sep 3, 1:23 PM PDT · 15734 days ago · 3 km deep · 2 km away
40. 1.56 km W of Cobb, CaliforniaSat, Sep 3, 10:07 PM PDT · 15734 days ago · 3 km deep · 2 km away
41. 2.16 km W of Cobb, CaliforniaSun, Sep 4, 7:59 PM PDT · 15733 days ago · 3 km deep · 2 km away
42. 1.78 km W of Cobb, CaliforniaSun, Sep 4, 10:02 PM PDT · 15733 days ago · 0 km deep · 3 km away
43. 1.65 km SW of Cobb, CaliforniaMon, Sep 5, 6:35 AM PDT · 15732 days ago · 0 km deep · 2 km away
44. 1.75 km SW of Cobb, CaliforniaMon, Sep 5, 7:20 AM PDT · 15732 days ago · 0 km deep · 2 km away
45. 1.710 km NNE of Cloverdale, CaliforniaMon, Sep 5, 8:45 AM PDT · 15732 days ago · 12 km deep · 20 km away
46. 1.78 km WSW of Cobb, CaliforniaMon, Sep 5, 6:25 PM PDT · 15732 days ago · 3 km deep · 1 km away
47. 2.69 km WSW of Cobb, CaliforniaMon, Sep 5, 11:42 PM PDT · 15731 days ago · 1 km deep · 3 km away
48. 1.67 km SSE of Cobb, CaliforniaTue, Sep 6, 2:12 AM PDT · 15731 days ago · -1 km deep · 9 km away
49. 1.98 km WSW of Cobb, CaliforniaTue, Sep 6, 7:03 AM PDT · 15731 days ago · 1 km deep · 2 km away
50. 2.66 km W of Cobb, CaliforniaWed, Sep 7, 3:48 AM PDT · 15730 days ago · 3 km deep · 2 km away
51. 1.87 km W of Cobb, CaliforniaThu, Sep 8, 11:26 AM PDT · 15729 days ago · 0 km deep · 3 km away
52. 1.76 km W of Cobb, CaliforniaThu, Sep 8, 4:04 PM PDT · 15729 days ago · 3 km deep · 2 km away
53. 2.06 km W of Cobb, CaliforniaThu, Sep 8, 5:47 PM PDT · 15729 days ago · 3 km deep · 2 km away
54. 2.06 km SE of College City, CaliforniaFri, Sep 9, 7:15 AM PDT · 15728 days ago · 1 km deep · 76 km away
55. 2.18 km WSW of Cobb, CaliforniaFri, Sep 9, 7:22 AM PDT · 15728 days ago · -1 km deep · 2 km away
56. 2.57 km NNE of Dunnigan, CaliforniaFri, Sep 9, 9:04 AM PDT · 15728 days ago · 2 km deep · 75 km away
57. 2.63 km WNW of Dunnigan, CaliforniaFri, Sep 9, 10:45 AM PDT · 15728 days ago · 11 km deep · 69 km away
58. 2.35 km SW of Cobb, CaliforniaFri, Sep 9, 3:03 PM PDT · 15728 days ago · 0 km deep · 2 km away
59. 1.89 km S of Moskowite Corner, CaliforniaSat, Sep 10, 2:35 PM PDT · 15727 days ago · 7 km deep · 72 km away
60. 1.510 km ESE of Hidden Valley Lake, CaliforniaSun, Sep 11, 1:15 AM PDT · 15726 days ago · 6 km deep · 30 km away

The first 60 of 179.

Before

1. 3.16 km WSW of Cobb, CaliforniaTue, Aug 23, 1:40 PM PDT · 15745 days ago · 1 km deep · 1 km away
2. 1.89 km W of Redwood Valley, CaliforniaMon, Aug 22, 4:12 PM PDT · 15746 days ago · 6 km deep · 70 km away
3. 1.65 km W of Cobb, CaliforniaMon, Aug 22, 5:50 AM PDT · 15746 days ago · 0 km deep · 2 km away
4. 1.77 km W of Cobb, CaliforniaMon, Aug 22, 5:04 AM PDT · 15746 days ago · 3 km deep · 2 km away
5. 1.68 km WSW of Cobb, CaliforniaSun, Aug 21, 11:50 PM PDT · 15746 days ago · 2 km deep · 2 km away
6. 3.07 km W of Cobb, CaliforniaSat, Aug 20, 4:32 PM PDT · 15748 days ago · 3 km deep · 3 km away
7. 2.29 km WSW of Cobb, CaliforniaSat, Aug 20, 1:18 AM PDT · 15748 days ago · 2 km deep · 3 km away
8. 1.98 km WSW of Cobb, CaliforniaFri, Aug 19, 5:05 AM PDT · 15749 days ago · 3 km deep · 1 km away
9. 2.37 km W of Cobb, CaliforniaThu, Aug 18, 10:52 PM PDT · 15749 days ago · 2 km deep · 2 km away
10. 2.06 km SW of Cobb, CaliforniaThu, Aug 18, 8:17 PM PDT · 15750 days ago · -1 km deep · 2 km away
11. 2.25 km SW of Cobb, CaliforniaThu, Aug 18, 8:17 PM PDT · 15750 days ago · -1 km deep · 2 km away
12. 2.53 km ESE of Kenwood, CaliforniaThu, Aug 18, 5:02 PM PDT · 15750 days ago · 1 km deep · 51 km away
13. 2.04 km NNE of Glen Ellen, CaliforniaThu, Aug 18, 9:12 AM PDT · 15750 days ago · 3 km deep · 52 km away
14. 1.822 km NE of Potter Valley, CaliforniaThu, Aug 18, 12:22 AM PDT · 15750 days ago · 7 km deep · 77 km away
15. 1.66 km ESE of Willits, CaliforniaThu, Aug 18, 12:07 AM PDT · 15750 days ago · 9 km deep · 78 km away
16. 2.06 km ESE of Willits, CaliforniaWed, Aug 17, 11:52 PM PDT · 15750 days ago · 9 km deep · 78 km away
17. 1.56 km WSW of Cobb, CaliforniaWed, Aug 17, 8:08 PM PDT · 15751 days ago · 0 km deep · 0 km away
18. 1.89 km WSW of Cobb, CaliforniaTue, Aug 16, 11:45 AM PDT · 15752 days ago · 2 km deep · 2 km away
19. 2.01 km ESE of Larkfield-Wikiup, CaliforniaTue, Aug 16, 8:26 AM PDT · 15752 days ago · 4 km deep · 33 km away
20. 1.84 km WSW of Cobb, CaliforniaTue, Aug 16, 5:42 AM PDT · 15752 days ago · 1 km deep · 2 km away

From the USGS Earthquake Hazards Program and its partner networks, event nc1100921. Read Thu, Oct 1, 2026, 4:52 PM UTC.