M1.8 earthquake 2 km SW of Ridgemark, California

Magnitude

1.8 (Md, duration), micro

Magnitude from

Northern California Seismic System

Local time

Mon, Aug 4, 1975, 1:01 PM PDT

UTC

1975-08-04 20:01:39 UTC

Depth

8.0 km (5.0 mi), shallow

Epicenter

36.798° N, 121.387° W

Region

California

Tsunami flag

No

Status

Reviewed by a seismologist

Location uncertainty

About 0.2 km horizontally, 0.5 km in depth

Magnitude uncertainty

±0.16

Depth from

From location

Station coverage gap

39°

Stations used

28

• Ridgemark, CaliforniaPopulation 3,016. Forecast3 kmSW
• Hollister, CaliforniaPopulation 37,462. Forecast6 kmSSE
• Salinas, CaliforniaPopulation 157,380. Forecast27 kmENE
• Los Angeles, CaliforniaPopulation 3,820,914. Forecast417 kmNW

After

1. 3.16 km S of Three Rocks, CaliforniaTue, Aug 5, 2:44 AM PDT · 18689 days ago · 14 km deep · 97 km away
2. 2.78 km NW of Hollister, CaliforniaTue, Aug 5, 2:19 PM PDT · 18688 days ago · 6 km deep · 15 km away
3. 2.527 km NE of Soledad, CaliforniaTue, Aug 5, 4:11 PM PDT · 18688 days ago · 9 km deep · 36 km away
4. 2.022 km NNE of Soledad, CaliforniaTue, Aug 5, 5:37 PM PDT · 18688 days ago · 5 km deep · 27 km away
5. 2.35 km SSW of Tres Pinos, CaliforniaTue, Aug 5, 8:47 PM PDT · 18688 days ago · 8 km deep · 7 km away
6. 2.525 km NNE of King City, CaliforniaWed, Aug 6, 3:22 AM PDT · 18688 days ago · 1 km deep · 57 km away
7. 1.68 km NW of Hollister, CaliforniaWed, Aug 6, 5:31 AM PDT · 18688 days ago · 7 km deep · 14 km away
8. 2.541 km W of Three Rocks, CaliforniaWed, Aug 6, 7:19 AM PDT · 18688 days ago · 4 km deep · 56 km away
9. 2.18 km NE of Gilroy, CaliforniaWed, Aug 6, 9:55 AM PDT · 18688 days ago · 4 km deep · 30 km away
10. 4.08 km NE of Gilroy, CaliforniaWed, Aug 6, 3:23 PM PDT · 18687 days ago · 4 km deep · 31 km away
11. 1.69 km NE of Gilroy, CaliforniaWed, Aug 6, 3:46 PM PDT · 18687 days ago · 4 km deep · 30 km away
12. 1.89 km NE of Gilroy, CaliforniaWed, Aug 6, 7:16 PM PDT · 18687 days ago · 5 km deep · 30 km away
13. 2.62 km NW of Sand City, CaliforniaWed, Aug 6, 9:52 PM PDT · 18687 days ago · 5 km deep · 47 km away
14. 2.122 km ENE of Soledad, CaliforniaThu, Aug 7, 1:33 AM PDT · 18687 days ago · 2 km deep · 39 km away
15. 1.98 km N of Day Valley, CaliforniaThu, Aug 7, 6:51 AM PDT · 18687 days ago · 11 km deep · 56 km away
16. 3.68 km S of Three Rocks, CaliforniaThu, Aug 7, 2:42 PM PDT · 18686 days ago · 11 km deep · 99 km away
17. 3.18 km S of Three Rocks, CaliforniaThu, Aug 7, 2:46 PM PDT · 18686 days ago · 16 km deep · 98 km away
18. 3.98 km S of Three Rocks, CaliforniaThu, Aug 7, 11:28 PM PDT · 18686 days ago · 15 km deep · 98 km away
19. 1.67 km ENE of East Foothills, CaliforniaFri, Aug 8, 1:50 PM PDT · 18685 days ago · 1 km deep · 74 km away
20. 4.0Central CaliforniaFri, Aug 8, 3:23 PM PDT · 18685 days ago · 11 km deep · 98 km away
21. 2.89 km NW of Hollister, CaliforniaFri, Aug 8, 5:59 PM PDT · 18685 days ago · 4 km deep · 16 km away
22. 3.19 km NNW of Hollister, CaliforniaFri, Aug 8, 6:18 PM PDT · 18685 days ago · 5 km deep · 16 km away
23. 2.612 km S of Tres Pinos, CaliforniaSat, Aug 9, 12:32 AM PDT · 18685 days ago · 2 km deep · 15 km away
24. 2.717 km SSE of Tres Pinos, CaliforniaSat, Aug 9, 12:34 AM PDT · 18685 days ago · 6 km deep · 21 km away
25. 2.46 km NW of Hollister, CaliforniaSat, Aug 9, 5:40 AM PDT · 18685 days ago · 7 km deep · 13 km away
26. 1.66 km NNE of East Foothills, CaliforniaSat, Aug 9, 11:18 AM PDT · 18685 days ago · 6 km deep · 79 km away
27. 3.48 km NW of Hollister, CaliforniaSun, Aug 10, 10:16 AM PDT · 18684 days ago · 8 km deep · 14 km away
28. 1.620 km NE of Soledad, CaliforniaSun, Aug 10, 3:08 PM PDT · 18683 days ago · 7 km deep · 34 km away
29. 2.08 km ESE of Tres Pinos, CaliforniaSun, Aug 10, 4:58 PM PDT · 18683 days ago · 4 km deep · 15 km away
30. 3.027 km NE of Soledad, CaliforniaMon, Aug 11, 4:03 AM PDT · 18683 days ago · 9 km deep · 38 km away
31. 2.46 km ENE of East Foothills, CaliforniaMon, Aug 11, 4:14 PM PDT · 18682 days ago · 5 km deep · 74 km away
32. 2.824 km NE of King City, CaliforniaMon, Aug 11, 11:06 PM PDT · 18682 days ago · 2 km deep · 61 km away
33. 1.77 km ESE of Lexington Hills, CaliforniaTue, Aug 12, 1:42 AM PDT · 18682 days ago · 12 km deep · 59 km away
34. 2.521 km ENE of San Lucas, CaliforniaTue, Aug 12, 5:37 AM PDT · 18682 days ago · 3 km deep · 84 km away
35. 3.0Central CaliforniaTue, Aug 12, 2:39 PM PDT · 18681 days ago · 4 km deep · 29 km away
36. 2.76 km NW of Hollister, CaliforniaWed, Aug 13, 10:07 AM PDT · 18681 days ago · 8 km deep · 13 km away
37. 2.18 km NW of Hollister, CaliforniaWed, Aug 13, 2:59 PM PDT · 18680 days ago · 7 km deep · 15 km away
38. 2.39 km NW of Hollister, CaliforniaThu, Aug 14, 9:28 AM PDT · 18680 days ago · 6 km deep · 16 km away
39. 2.523 km NE of Soledad, CaliforniaFri, Aug 15, 12:06 AM PDT · 18679 days ago · 9 km deep · 34 km away
40. 2.514 km E of Seven Trees, CaliforniaFri, Aug 15, 1:22 AM PDT · 18679 days ago · 2 km deep · 60 km away
41. 2.216 km SSE of Tres Pinos, CaliforniaFri, Aug 15, 1:24 AM PDT · 18679 days ago · 2 km deep · 20 km away
42. 2.624 km NE of Soledad, CaliforniaFri, Aug 15, 1:56 AM PDT · 18679 days ago · 10 km deep · 35 km away
43. 4.65 km SSW of Three Rocks, CaliforniaFri, Aug 15, 3:27 PM PDT · 18678 days ago · 12 km deep · 94 km away
44. 3.33 km WSW of San Juan Bautista, CaliforniaFri, Aug 15, 3:40 PM PDT · 18678 days ago · 8 km deep · 18 km away
45. 2.229 km ENE of Soledad, CaliforniaSat, Aug 16, 12:58 AM PDT · 18678 days ago · 7 km deep · 39 km away
46. 2.426 km NE of King City, CaliforniaSat, Aug 16, 5:18 AM PDT · 18678 days ago · 3 km deep · 60 km away
47. 3.15 km SSW of Gilroy, CaliforniaSat, Aug 16, 10:30 AM PDT · 18678 days ago · 4 km deep · 26 km away
48. 2.324 km NE of Soledad, CaliforniaSat, Aug 16, 8:41 PM PDT · 18677 days ago · 7 km deep · 38 km away
49. 1.924 km ENE of Soledad, CaliforniaSat, Aug 16, 9:12 PM PDT · 18677 days ago · 7 km deep · 38 km away
50. 2.221 km NE of Soledad, CaliforniaSat, Aug 16, 9:38 PM PDT · 18677 days ago · 5 km deep · 31 km away
51. 2.69 km NW of Hollister, CaliforniaSat, Aug 16, 11:19 PM PDT · 18677 days ago · 6 km deep · 15 km away
52. 4.16 km S of Three Rocks, CaliforniaSun, Aug 17, 1:52 AM PDT · 18677 days ago · 16 km deep · 98 km away
53. 2.321 km NNE of Soledad, CaliforniaSun, Aug 17, 6:17 AM PDT · 18677 days ago · 4 km deep · 29 km away
54. 2.52 km WSW of San Juan Bautista, CaliforniaSun, Aug 17, 11:53 AM PDT · 18677 days ago · 8 km deep · 17 km away
55. 2.335 km ENE of Soledad, CaliforniaSun, Aug 17, 9:31 PM PDT · 18676 days ago · 6 km deep · 47 km away
56. 3.75 km SW of Three Rocks, CaliforniaMon, Aug 18, 1:35 AM PDT · 18676 days ago · 16 km deep · 93 km away
57. 3.225 km ENE of Greenfield, CaliforniaMon, Aug 18, 11:52 PM PDT · 18675 days ago · 1 km deep · 52 km away
58. 1.69 km NE of Milpitas, CaliforniaTue, Aug 19, 12:44 AM PDT · 18675 days ago · 8 km deep · 88 km away
59. 2.123 km ENE of Soledad, CaliforniaTue, Aug 19, 7:29 PM PDT · 18674 days ago · 1 km deep · 41 km away
60. 1.824 km ESE of Tres Pinos, CaliforniaWed, Aug 20, 3:16 AM PDT · 18674 days ago · 4 km deep · 30 km away

The first 60 of 188.

Before

1. 3.621 km SSE of Tres Pinos, CaliforniaMon, Aug 4, 10:05 AM PDT · 18690 days ago · 4 km deep · 25 km away
2. 2.70 km NNW of Hollister, CaliforniaMon, Aug 4, 7:35 AM PDT · 18690 days ago · 6 km deep · 7 km away
3. 2.83 km SSE of Three Rocks, CaliforniaMon, Aug 4, 5:21 AM PDT · 18690 days ago · 7 km deep · 97 km away
4. 3.037 km W of Three Rocks, CaliforniaMon, Aug 4, 2:33 AM PDT · 18690 days ago · 1 km deep · 60 km away
5. 3.13 km SE of Three Rocks, CaliforniaMon, Aug 4, 1:02 AM PDT · 18690 days ago · 2 km deep · 98 km away
6. 3.47 km S of Three Rocks, CaliforniaMon, Aug 4, 12:30 AM PDT · 18690 days ago · 19 km deep · 98 km away
7. 3.58 km S of Three Rocks, CaliforniaMon, Aug 4, 12:14 AM PDT · 18690 days ago · 10 km deep · 99 km away
8. 2.122 km NE of San Lucas, CaliforniaSun, Aug 3, 8:20 PM PDT · 18690 days ago · 8 km deep · 74 km away
9. 2.42 km SW of Ridgemark, CaliforniaSun, Aug 3, 8:09 PM PDT · 18690 days ago · 8 km deep · 0 km away
10. 1.98 km ENE of San Martin, CaliforniaSun, Aug 3, 6:49 PM PDT · 18690 days ago · 6 km deep · 37 km away
11. 3.224 km ENE of Greenfield, CaliforniaSun, Aug 3, 6:48 PM PDT · 18690 days ago · 5 km deep · 52 km away
12. 2.224 km ENE of Greenfield, CaliforniaSun, Aug 3, 6:45 PM PDT · 18690 days ago · 5 km deep · 53 km away
13. 2.331 km ENE of Soledad, CaliforniaSun, Aug 3, 6:44 PM PDT · 18690 days ago · 7 km deep · 40 km away
14. 3.06 km S of Three Rocks, CaliforniaSun, Aug 3, 3:39 PM PDT · 18690 days ago · 11 km deep · 97 km away
15. 4.46 km S of Three Rocks, CaliforniaSun, Aug 3, 9:58 AM PDT · 18691 days ago · 11 km deep · 96 km away
16. 3.84 km S of Three Rocks, CaliforniaSun, Aug 3, 9:00 AM PDT · 18691 days ago · 9 km deep · 96 km away
17. 3.18 km S of Three Rocks, CaliforniaSun, Aug 3, 7:01 AM PDT · 18691 days ago · 15 km deep · 97 km away
18. 3.5Central CaliforniaSun, Aug 3, 6:46 AM PDT · 18691 days ago · 11 km deep · 97 km away
19. 3.07 km S of Three Rocks, CaliforniaSun, Aug 3, 6:46 AM PDT · 18691 days ago · 18 km deep · 98 km away
20. 1.613 km S of Tres Pinos, CaliforniaSun, Aug 3, 5:03 AM PDT · 18691 days ago · 5 km deep · 17 km away

From the USGS Earthquake Hazards Program and its partner networks, event nc1025322. Read Mon, Oct 5, 2026, 6:34 AM UTC.