California earthquakes

M1.5 earthquake 4 km WSW of Ridgemark, California

A magnitude 1.5 earthquake struck 4 km WSW of Ridgemark, California on Wed, Aug 22, 1990, 6:09 AM PDT (13:09 UTC), 5 km (3 mi) below the surface.

A larger quake followed: M4.4 14 km S of Tres Pinos, California. This one was a foreshock.

Ridgemark forecastMore in California

Map

Where this earthquake was located, with the others nearby. Select one for its page.

Open the live map with earthquakes

The earthquake

Magnitude
1.5 (Md, duration), micro
Magnitude from
Northern California Seismic System
Local time
UTC
1990-08-22 13:09:30 UTC
Depth
4.9 km (3.0 mi), shallow
Epicenter
36.803° N, 121.413° W
Tsunami flag
No
Status
Reviewed by a seismologist

Did you feel it?

No one has reported feeling this quake to the USGS.

How well it is located

Reviewed by a seismologist.

Location uncertainty
About 0.3 km horizontally, 0.7 km in depth
Magnitude uncertainty
±0.20
Depth from
From location
Station coverage gap
41°
Stations used
26

Nearest places

Distance and direction from each place to the epicenter, with its forecast.

Nearby

Within 100 km, magnitude 1.5 and up: 183 in the 60 days after this one and 106 in the 30 days before it.

After

  1. 1.614 km ENE of East Foothills, California · 13191 days ago · 4 km deep · 73 km away
  2. 1.95 km WNW of San Juan Bautista, California · 13191 days ago · 7 km deep · 17 km away
  3. 1.57 km WSW of Monte Sereno, California · 13191 days ago · 12 km deep · 73 km away
  4. 3.67 km WSW of Monte Sereno, California · 13191 days ago · 13 km deep · 73 km away
  5. 2.820km SSE of King City, CA · 13191 days ago · 5 km deep · 91 km away
  6. 1.96 km WSW of Monte Sereno, California · 13191 days ago · 12 km deep · 73 km away
  7. 1.66 km NE of East Foothills, California · 13191 days ago · 7 km deep · 75 km away
  8. 1.924 km ENE of Greenfield, California · 13191 days ago · 5 km deep · 54 km away
  9. 2.02 km N of Scotts Valley, California · 13190 days ago · 11 km deep · 61 km away
  10. 1.917 km SSE of Tres Pinos, California · 13189 days ago · 5 km deep · 23 km away
  11. 1.731 km SSW of Los Banos, California · 13189 days ago · 1 km deep · 40 km away
  12. 1.9Northern California · 13189 days ago · 6 km deep · 91 km away
  13. 1.514 km SSE of Davenport, California · 13189 days ago · 6 km deep · 67 km away
  14. 1.74 km E of Interlaken, California · 13188 days ago · 9 km deep · 29 km away
  15. 3.33 km NW of Day Valley, California · 13188 days ago · 6 km deep · 51 km away
  16. 3.512 km S of Tres Pinos, CA · 13188 days ago · 5 km deep · 16 km away
  17. 3.012 km S of Tres Pinos, California · 13188 days ago · 5 km deep · 17 km away
  18. 2.59 km S of Tres Pinos, California · 13188 days ago · 3 km deep · 13 km away
  19. 2.324 km NE of Soledad, California · 13188 days ago · 1 km deep · 40 km away
  20. 1.51 km ESE of Aromas, California · 13188 days ago · 8 km deep · 21 km away
  21. 2.423 km ENE of Soledad, California · 13188 days ago · 4 km deep · 46 km away
  22. 2.5Central California · 13187 days ago · 2 km deep · 32 km away
  23. 2.04 km E of Day Valley, California · 13187 days ago · 11 km deep · 44 km away
  24. 2.01 km ESE of Aromas, California · 13187 days ago · 8 km deep · 21 km away
  25. 2.4Central California · 13187 days ago · 9 km deep · 30 km away
  26. 1.61 km NE of Aromas, California · 13187 days ago · 5 km deep · 22 km away
  27. 2.49 km S of Tres Pinos, California · 13186 days ago · 2 km deep · 13 km away
  28. 1.87 km WNW of Lexington Hills, California · 13186 days ago · 14 km deep · 71 km away
  29. 1.917 km S of Pescadero, California · 13186 days ago · 7 km deep · 92 km away
  30. 2.022 km NE of Soledad, California · 13185 days ago · 8 km deep · 38 km away
  31. 2.86 km WSW of Monte Sereno, California · 13185 days ago · 12 km deep · 73 km away
  32. 1.56 km N of Tres Pinos, California · 13185 days ago · 6 km deep · 10 km away
  33. 1.97 km NW of Day Valley, California · 13185 days ago · 11 km deep · 55 km away
  34. 2.511 km S of Tres Pinos, California · 13184 days ago · 4 km deep · 16 km away
  35. 2.113 km WNW of Davenport, California · 13184 days ago · 11 km deep · 86 km away
  36. 2.46 km SSW of Saratoga, California · 13184 days ago · 12 km deep · 73 km away
  37. 1.68 km N of East Foothills, California · 13184 days ago · 6 km deep · 81 km away
  38. 3.012 km S of Tres Pinos, California · 13183 days ago · 5 km deep · 17 km away
  39. 2.412 km S of Tres Pinos, California · 13183 days ago · 5 km deep · 16 km away
  40. 2.612 km S of Tres Pinos, California · 13182 days ago · 5 km deep · 17 km away
  41. 1.56 km NE of Ridgemark, California · 13182 days ago · 7 km deep · 10 km away
  42. 1.912 km S of Tres Pinos, California · 13182 days ago · 5 km deep · 17 km away
  43. 1.912 km S of Tres Pinos, California · 13182 days ago · 5 km deep · 17 km away
  44. 1.612 km S of Tres Pinos, California · 13182 days ago · 5 km deep · 17 km away
  45. 1.85 km NW of Day Valley, California · 13182 days ago · 13 km deep · 53 km away
  46. 2.113 km WNW of Davenport, California · 13181 days ago · 10 km deep · 86 km away
  47. 2.26 km NE of Ridgemark, California · 13181 days ago · 6 km deep · 10 km away
  48. 2.9Central California · 13181 days ago · 9 km deep · 8 km away
  49. 1.63 km ESE of Lexington Hills, California · 13181 days ago · 4 km deep · 60 km away
  50. 3.513 km S of Tres Pinos, California · 13180 days ago · 6 km deep · 18 km away
  51. 2.813 km S of Tres Pinos, California · 13180 days ago · 6 km deep · 18 km away
  52. 1.913 km S of Tres Pinos, California · 13180 days ago · 3 km deep · 18 km away
  53. 3.313 km SSE of Tres Pinos, California · 13180 days ago · 6 km deep · 19 km away
  54. 2.314 km SSE of Tres Pinos, California · 13180 days ago · 5 km deep · 19 km away
  55. 1.714 km SSE of Tres Pinos, California · 13180 days ago · 5 km deep · 19 km away
  56. 1.614 km E of Seven Trees, California · 13180 days ago · 1 km deep · 59 km away
  57. 1.819 km WSW of Volta, California · 13179 days ago · 1 km deep · 37 km away
  58. 1.713 km S of Tres Pinos, California · 13179 days ago · 5 km deep · 18 km away
  59. 2.314 km SSE of Tres Pinos, California · 13179 days ago · 5 km deep · 19 km away
  60. 1.524 km NE of Greenfield, California · 13179 days ago · 5 km deep · 49 km away

The first 60 of 183.

Before

  1. 2.45 km NE of Amesti, California · 13191 days ago · 8 km deep · 37 km away
  2. 2.66 km ENE of Corralitos, California · 13191 days ago · 7 km deep · 38 km away
  3. 1.911 km N of Boulder Creek, California · 13191 days ago · 10 km deep · 80 km away
  4. 2.02 km NNE of Corralitos, California · 13192 days ago · 14 km deep · 41 km away
  5. 1.6Central California · 13192 days ago · 10 km deep · 78 km away
  6. 2.38 km W of Volta, California · 13192 days ago · 1 km deep · 47 km away
  7. 2.7Central California · 13192 days ago · 8 km deep · 38 km away
  8. 1.5Northern California · 13192 days ago · 15 km deep · 92 km away
  9. 1.510 km SSE of Pescadero, California · 13192 days ago · 14 km deep · 92 km away
  10. 1.611 km S of Pescadero, California · 13192 days ago · 14 km deep · 93 km away
  11. 2.210 km SSE of Pescadero, California · 13192 days ago · 15 km deep · 92 km away
  12. 1.722 km NE of Soledad, California · 13192 days ago · 8 km deep · 38 km away
  13. 2.110 km SSE of Pescadero, California · 13192 days ago · 14 km deep · 92 km away
  14. 1.812 km SE of Tres Pinos, California · 13192 days ago · 2 km deep · 20 km away
  15. 1.68 km NE of San Martin, California · 13192 days ago · 7 km deep · 38 km away
  16. 2.94 km SE of Aromas, California · 13192 days ago · 7 km deep · 18 km away
  17. 1.922 km NE of Soledad, California · 13193 days ago · 2 km deep · 39 km away
  18. 3.11 km ESE of Aromas, California · 13193 days ago · 9 km deep · 21 km away
  19. 1.55 km WNW of San Juan Bautista, California · 13193 days ago · 6 km deep · 17 km away
  20. 2.022 km NE of Soledad, California · 13194 days ago · 8 km deep · 38 km away

Earthquakes todayCalifornia earthquakesLive radar here

Sources

From the USGS Earthquake Hazards Program and its partner networks, event nc163058. Read Sat, Oct 3, 2026, 3:18 PM UTC.