M4.0 earthquake 40 km WSW of Ferndale, California

Magnitude

4.0 (ml), light

Local time

Sat, Apr 23, 1983, 2:52 PM PST

UTC

1983-04-23 22:52:26 UTC

Depth

20.2 km (12.6 mi), shallow

Epicenter

40.409° N, 124.691° W

Region

California

Tsunami flag

No

Status

Reviewed by a seismologist

Location uncertainty

About 0.4 km horizontally, 0.5 km in depth

Depth from

From location

Station coverage gap

245°, poorly surrounded by stations

Stations used

34

• Ferndale, CaliforniaPopulation 1,369. Forecast41 kmWSW
• Fortuna, CaliforniaPopulation 12,000. Forecast50 kmWSW
• Chico, CaliforniaPopulation 121,345. Forecast254 kmWNW

After

1. 3.355 km WSW of Ferndale, CaliforniaSat, Apr 23, 7:08 PM PST · 15858 days ago · 23 km deep · 14 km away
2. 2.115 km ESE of Indianola, CaliforniaSat, Apr 23, 10:50 PM PST · 15857 days ago · 20 km deep · 76 km away
3. 3.216 km SW of Ferndale, CaliforniaSun, Apr 24, 10:08 AM PDT · 15857 days ago · 25 km deep · 24 km away
4. 1.620 km WSW of Weott, CaliforniaTue, Apr 26, 8:58 AM PDT · 15855 days ago · -1 km deep · 51 km away
5. 1.534 km SSW of Ferndale, CaliforniaTue, Apr 26, 6:37 PM PDT · 15855 days ago · 5 km deep · 26 km away
6. 1.528 km WNW of Ferndale, CaliforniaWed, Apr 27, 10:09 AM PDT · 15854 days ago · 23 km deep · 31 km away
7. 2.041 km SW of Ferndale, CaliforniaThu, Apr 28, 3:24 AM PDT · 15853 days ago · 10 km deep · 17 km away
8. 2.9121 km W of Ferndale, CaliforniaThu, Apr 28, 11:45 AM PDT · 15853 days ago · 7 km deep · 86 km away
9. 1.811 km SW of Scotia, CaliforniaFri, Apr 29, 7:31 AM PDT · 15852 days ago · 30 km deep · 44 km away
10. 3.128 km SSW of Ferndale, CaliforniaFri, Apr 29, 1:48 PM PDT · 15852 days ago · 18 km deep · 22 km away
11. 1.924 km SSW of Ferndale, CaliforniaSun, May 1, 10:02 AM PDT · 15850 days ago · 19 km deep · 23 km away
12. 2.026 km SSW of Ferndale, CaliforniaSun, May 1, 5:19 PM PDT · 15850 days ago · 16 km deep · 28 km away
13. 1.624 km WSW of Ferndale, CaliforniaSun, May 1, 8:47 PM PDT · 15850 days ago · 23 km deep · 18 km away
14. 2.595 km WNW of Indianola, CaliforniaWed, May 4, 9:19 PM PDT · 15847 days ago · 5 km deep · 77 km away
15. 2.132 km SSW of Ferndale, CaliforniaThu, May 5, 11:38 AM PDT · 15846 days ago · 5 km deep · 27 km away
16. 1.831 km SW of Ferndale, CaliforniaFri, May 6, 7:25 PM PDT · 15845 days ago · 25 km deep · 10 km away
17. 1.736 km WSW of Ferndale, CaliforniaFri, May 6, 8:52 PM PDT · 15845 days ago · 23 km deep · 5 km away
18. 2.911 km WNW of Fields Landing, CaliforniaFri, May 6, 11:09 PM PDT · 15844 days ago · 20 km deep · 47 km away
19. 1.614 km ENE of Hydesville, CaliforniaSat, May 7, 8:25 AM PDT · 15844 days ago · 22 km deep · 67 km away
20. 2.025 km WNW of Samoa, CaliforniaSun, May 8, 9:40 AM PDT · 15843 days ago · 29 km deep · 59 km away
21. 2.735 km SSW of Ferndale, CaliforniaMon, May 9, 5:48 PM PDT · 15842 days ago · 19 km deep · 23 km away
22. 1.7near the coast of Northern CaliforniaMon, May 9, 8:56 PM PDT · 15842 days ago · 25 km deep · 46 km away
23. 2.9111 km W of Ferndale, CaliforniaTue, May 10, 12:43 PM PDT · 15841 days ago · 5 km deep · 74 km away
24. 3.443 km SW of Ferndale, CaliforniaTue, May 10, 11:48 PM PDT · 15840 days ago · 23 km deep · 6 km away
25. 2.214 km WSW of Ferndale, CaliforniaWed, May 11, 9:33 PM PDT · 15840 days ago · 16 km deep · 26 km away
26. 2.743 km SW of Ferndale, CaliforniaThu, May 12, 5:18 AM PDT · 15839 days ago · 21 km deep · 12 km away
27. 2.136 km SSW of Ferndale, CaliforniaThu, May 12, 2:48 PM PDT · 15839 days ago · 20 km deep · 20 km away
28. 2.129 km SW of Ferndale, CaliforniaFri, May 13, 6:42 AM PDT · 15838 days ago · 21 km deep · 17 km away
29. 2.917 km SW of Scotia, CaliforniaFri, May 13, 1:29 PM PDT · 15838 days ago · 32 km deep · 40 km away
30. 1.68 km NE of Hydesville, CaliforniaSat, May 14, 4:14 AM PDT · 15837 days ago · 22 km deep · 60 km away
31. 2.816 km WNW of Indianola, CaliforniaSun, May 15, 8:49 AM PDT · 15836 days ago · 25 km deep · 45 km away
32. 2.030 km WSW of Ferndale, CaliforniaSun, May 15, 3:01 PM PDT · 15836 days ago · 26 km deep · 13 km away
33. 1.725 km SSW of Ferndale, CaliforniaSun, May 15, 7:15 PM PDT · 15836 days ago · 12 km deep · 27 km away
34. 2.710 km SE of Blue Lake, CaliforniaTue, May 17, 7:39 AM PDT · 15834 days ago · 20 km deep · 82 km away
35. 4.461 km SW of Ferndale, CaliforniaTue, May 17, 5:50 PM PDT · 15834 days ago · 5 km deep · 23 km away
36. 3.869 km WSW of Ferndale, CaliforniaTue, May 17, 6:10 PM PDT · 15834 days ago · 5 km deep · 29 km away
37. 2.538 km SW of Ferndale, CaliforniaSat, May 21, 12:59 PM PDT · 15830 days ago · 21 km deep · 18 km away
38. 1.731 km SSW of Ferndale, CaliforniaSun, May 22, 6:14 AM PDT · 15829 days ago · 10 km deep · 25 km away
39. 1.65 km NNW of Redway, CaliforniaSun, May 22, 7:49 PM PDT · 15829 days ago · 15 km deep · 76 km away
40. 2.57 km NE of Fortuna, CaliforniaWed, May 25, 3:07 AM PDT · 15826 days ago · 18 km deep · 56 km away
41. 3.961 km W of Ferndale, CaliforniaThu, May 26, 4:55 AM PDT · 15825 days ago · 56 km deep · 26 km away
42. 3.338 km SW of Ferndale, CaliforniaFri, May 27, 9:19 AM PDT · 15824 days ago · 20 km deep · 18 km away
43. 2.139 km SW of Ferndale, CaliforniaFri, May 27, 3:35 PM PDT · 15824 days ago · 11 km deep · 15 km away
44. 2.491 km W of Ferndale, CaliforniaSat, May 28, 3:59 PM PDT · 15823 days ago · 5 km deep · 55 km away
45. 1.95 km S of Ferndale, CaliforniaSat, May 28, 5:03 PM PDT · 15823 days ago · 21 km deep · 37 km away
46. 5.1100 km W of Ferndale, CaliforniaSat, May 28, 11:55 PM PDT · 15822 days ago · 10 km deep · 64 km away
47. 3.0130 km W of Ferndale, CaliforniaSun, May 29, 12:01 AM PDT · 15822 days ago · 4 km deep · 95 km away
48. 2.7102 km W of Ferndale, CaliforniaSun, May 29, 12:48 AM PDT · 15822 days ago · 5 km deep · 65 km away
49. 2.544 km SW of Ferndale, CaliforniaMon, May 30, 7:36 PM PDT · 15821 days ago · 19 km deep · 8 km away
50. 2.05 km SE of Benbow, CaliforniaTue, May 31, 1:36 PM PDT · 15820 days ago · 15 km deep · 91 km away
51. 1.734 km SSW of Ferndale, CaliforniaTue, May 31, 4:56 PM PDT · 15820 days ago · 11 km deep · 25 km away
52. 1.733 km SSW of Ferndale, CaliforniaWed, Jun 1, 8:53 AM PDT · 15819 days ago · 15 km deep · 24 km away
53. 1.88 km WNW of Ferndale, CaliforniaThu, Jun 2, 10:08 AM PDT · 15818 days ago · 10 km deep · 36 km away
54. 1.514 km NE of Hydesville, CaliforniaThu, Jun 2, 10:22 PM PDT · 15818 days ago · 24 km deep · 67 km away
55. 2.013 km NW of Samoa, CaliforniaFri, Jun 3, 8:11 AM PDT · 15817 days ago · 23 km deep · 62 km away
56. 2.232 km WSW of Ferndale, CaliforniaFri, Jun 3, 9:18 AM PDT · 15817 days ago · 13 km deep · 9 km away
57. 2.35 km E of Scotia, CaliforniaSat, Jun 4, 3:59 AM PDT · 15816 days ago · 6 km deep · 56 km away
58. 3.031 km SW of Ferndale, CaliforniaSat, Jun 4, 4:34 PM PDT · 15816 days ago · 12 km deep · 12 km away
59. 1.617 km SW of Ferndale, CaliforniaMon, Jun 6, 9:44 PM PDT · 15814 days ago · 23 km deep · 24 km away
60. 1.614 km SW of Mad River, CaliforniaThu, Jun 9, 7:05 PM PDT · 15811 days ago · 21 km deep · 92 km away

The first 60 of 78.

Before

1. 1.511 km S of Ferndale, CaliforniaSat, Apr 23, 8:15 AM PST · 15858 days ago · 6 km deep · 36 km away
2. 1.514 km S of Ferndale, CaliforniaFri, Apr 22, 11:13 PM PST · 15858 days ago · 24 km deep · 34 km away
3. 2.118 km WNW of Hyampom, CaliforniaFri, Apr 22, 8:35 PM PST · 15859 days ago · 29 km deep · 95 km away
4. 1.635 km SSW of Ferndale, CaliforniaFri, Apr 22, 3:58 AM PST · 15859 days ago · 4 km deep · 26 km away
5. 2.419 km W of Ferndale, CaliforniaThu, Apr 21, 11:40 AM PST · 15860 days ago · 23 km deep · 27 km away
6. 1.619 km SSW of Ferndale, CaliforniaThu, Apr 21, 10:55 AM PST · 15860 days ago · 22 km deep · 29 km away
7. 1.939 km SSW of Ferndale, CaliforniaThu, Apr 21, 8:30 AM PST · 15860 days ago · 12 km deep · 23 km away
8. 2.119 km SW of Ferndale, CaliforniaWed, Apr 20, 9:41 PM PST · 15861 days ago · 22 km deep · 22 km away
9. 3.535 km SSW of Ferndale, CaliforniaWed, Apr 20, 1:44 PM PST · 15861 days ago · 19 km deep · 20 km away
10. 2.021 km SSW of Ferndale, CaliforniaWed, Apr 20, 1:33 PM PST · 15861 days ago · 21 km deep · 28 km away
11. 2.025 km SSW of Ferndale, CaliforniaWed, Apr 20, 1:30 PM PST · 15861 days ago · 20 km deep · 24 km away
12. 3.834 km SW of Ferndale, CaliforniaWed, Apr 20, 9:54 AM PST · 15861 days ago · 17 km deep · 19 km away
13. 2.760 km WSW of Ferndale, CaliforniaWed, Apr 20, 8:31 AM PST · 15861 days ago · 25 km deep · 20 km away
14. 1.88 km W of Rio Dell, CaliforniaTue, Apr 19, 5:25 PM PST · 15862 days ago · 20 km deep · 43 km away
15. 3.950 km W of Ferndale, CaliforniaTue, Apr 19, 2:09 PM PST · 15862 days ago · 85 km deep · 19 km away
16. 1.62 km N of Indianola, CaliforniaMon, Apr 18, 3:36 AM PST · 15863 days ago · 4 km deep · 51 km away
17. 2.314 km WNW of Ferndale, CaliforniaSun, Apr 17, 5:29 PM PST · 15864 days ago · 21 km deep · 33 km away
18. 1.758 km WNW of Fields Landing, CaliforniaSat, Apr 16, 2:24 PM PST · 15865 days ago · 9 km deep · 55 km away
19. 1.724 km WSW of Weott, CaliforniaSat, Apr 16, 7:35 AM PST · 15865 days ago · 6 km deep · 46 km away
20. 3.038 km SW of Ferndale, CaliforniaSat, Apr 16, 3:17 AM PST · 15865 days ago · 22 km deep · 12 km away

From the USGS Earthquake Hazards Program and its partner networks, event nc1090785 (also filed as usp0001uqh). Read Tue, Sep 22, 2026, 5:15 PM UTC.