California earthquakes

M1.7 earthquake 10 km SW of Ridgemark, California

A magnitude 1.7 earthquake struck 10 km SW of Ridgemark, California on Wed, Dec 7, 1977, 2:38 AM PST (10:38 UTC), 9 km (6 mi) below the surface.

A larger quake followed: M4.2 21 km NNE of Soledad, 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.

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The earthquake

Magnitude
1.7 (Md, duration), micro
Magnitude from
Northern California Seismic System
Local time
UTC
1977-12-07 10:38:35 UTC
Depth
8.9 km (5.5 mi), shallow
Epicenter
36.755° N, 121.457° 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 0.2 km horizontally, 0.4 km in depth
Magnitude uncertainty
±0.02
Depth from
From location
Station coverage gap
30°
Stations used
31

Nearest places

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

Nearby

Within 100 km, magnitude 1.5 and up: 152 in the 60 days after this one and 69 in the 30 days before it.

After

  1. 2.414 km ENE of East Foothills, California · 17830 days ago · 8 km deep · 77 km away
  2. 3.03 km WSW of San Juan Bautista, California · 17830 days ago · 7 km deep · 14 km away
  3. 1.98 km NE of Gilroy, California · 17829 days ago · 6 km deep · 35 km away
  4. 2.022 km NE of Soledad, California · 17829 days ago · 0 km deep · 36 km away
  5. 1.89 km ENE of San Martin, California · 17829 days ago · 6 km deep · 39 km away
  6. 1.613 km N of Morgan Hill, California · 17828 days ago · 5 km deep · 58 km away
  7. 2.322 km NE of Soledad, California · 17828 days ago · 9 km deep · 37 km away
  8. 1.53 km E of Interlaken, California · 17828 days ago · 9 km deep · 30 km away
  9. 1.725 km W of Coalinga, California · 17827 days ago · 6 km deep · 97 km away
  10. 2.512 km ESE of East Foothills, California · 17827 days ago · 7 km deep · 67 km away
  11. 1.628 km NE of Soledad, California · 17826 days ago · 6 km deep · 36 km away
  12. 1.95 km NNE of San Juan Bautista, California · 17826 days ago · 6 km deep · 16 km away
  13. 2.02 km NNW of Hollister, California · 17826 days ago · 7 km deep · 14 km away
  14. 2.55 km SSW of Gilroy, California · 17826 days ago · 7 km deep · 25 km away
  15. 3.612 km ESE of East Foothills, California · 17826 days ago · 7 km deep · 67 km away
  16. 1.712 km ESE of East Foothills, California · 17826 days ago · 6 km deep · 67 km away
  17. 2.412 km ESE of East Foothills, California · 17826 days ago · 7 km deep · 67 km away
  18. 2.222 km NE of San Lucas, California · 17826 days ago · 7 km deep · 80 km away
  19. 1.96 km WSW of Gilroy, California · 17826 days ago · 5 km deep · 30 km away
  20. 2.324 km NE of Greenfield, California · 17825 days ago · 6 km deep · 48 km away
  21. 1.923 km ENE of King City, California · 17824 days ago · 4 km deep · 69 km away
  22. 1.84 km SSW of Gilroy, California · 17823 days ago · 6 km deep · 26 km away
  23. 1.75 km SSW of Tres Pinos, California · 17823 days ago · 7 km deep · 11 km away
  24. 2.222 km ENE of San Ardo, California · 17822 days ago · 3 km deep · 100 km away
  25. 4.221 km NNE of Soledad, California · 17822 days ago · 8 km deep · 29 km away
  26. 1.921 km NNE of Soledad, California · 17822 days ago · 7 km deep · 29 km away
  27. 1.821 km NNE of Soledad, California · 17822 days ago · 7 km deep · 29 km away
  28. 1.521 km NNE of Soledad, California · 17822 days ago · 7 km deep · 29 km away
  29. 2.45 km WSW of Gilroy, California · 17822 days ago · 2 km deep · 29 km away
  30. 1.521 km NNE of Soledad, California · 17822 days ago · 7 km deep · 29 km away
  31. 2.421 km NNE of Soledad, California · 17822 days ago · 7 km deep · 29 km away
  32. 1.72 km SW of Hollister, California · 17821 days ago · 5 km deep · 10 km away
  33. 2.021 km NNE of Soledad, California · 17821 days ago · 7 km deep · 29 km away
  34. 1.921 km NNE of Soledad, California · 17821 days ago · 7 km deep · 29 km away
  35. 2.426 km NE of Greenfield, California · 17821 days ago · 5 km deep · 49 km away
  36. 2.521 km NNE of Soledad, California · 17820 days ago · 7 km deep · 29 km away
  37. 1.821 km NE of Soledad, California · 17820 days ago · 3 km deep · 31 km away
  38. 1.712 km ESE of East Foothills, California · 17820 days ago · 7 km deep · 67 km away
  39. 2.13 km SSE of San Juan Bautista, California · 17820 days ago · 4 km deep · 9 km away
  40. 1.610 km S of Tres Pinos, California · 17818 days ago · 4 km deep · 12 km away
  41. 2.126 km SW of Davenport, California · 17816 days ago · 1 km deep · 82 km away
  42. 2.22 km WSW of Portola Valley, California · 17816 days ago · 10 km deep · 100 km away
  43. 2.27 km E of East Foothills, California · 17815 days ago · 6 km deep · 73 km away
  44. 1.622 km NE of Soledad, California · 17815 days ago · 7 km deep · 36 km away
  45. 1.89 km NW of Hollister, California · 17815 days ago · 5 km deep · 17 km away
  46. 1.710 km ESE of East Foothills, California · 17815 days ago · 7 km deep · 69 km away
  47. 1.68 km NE of Milpitas, California · 17814 days ago · 7 km deep · 87 km away
  48. 2.51 km NNE of Tres Pinos, California · 17814 days ago · 8 km deep · 13 km away
  49. 1.66 km NNW of Hollister, California · 17814 days ago · 3 km deep · 17 km away
  50. 1.7Central California · 17813 days ago · 1 km deep · 52 km away
  51. 1.623 km WNW of Diablo Grande, California · 17813 days ago · 2 km deep · 78 km away
  52. 2.021 km NNE of Soledad, California · 17812 days ago · 8 km deep · 30 km away
  53. 1.714 km E of Seven Trees, California · 17812 days ago · 3 km deep · 63 km away
  54. 2.024 km NE of King City, California · 17810 days ago · 4 km deep · 61 km away
  55. 2.26 km WSW of Gilroy, California · 17810 days ago · 3 km deep · 29 km away
  56. 1.912 km SW of Tres Pinos, California · 17809 days ago · 9 km deep · 8 km away
  57. 2.211 km S of Tres Pinos, California · 17809 days ago · 4 km deep · 14 km away
  58. 2.36 km ESE of East Foothills, California · 17809 days ago · 2 km deep · 73 km away
  59. 2.04 km ESE of Aromas, California · 17807 days ago · 6 km deep · 18 km away
  60. 2.322 km NE of San Lucas, California · 17807 days ago · 6 km deep · 77 km away

The first 60 of 152.

Before

  1. 2.36 km WSW of Gilroy, California · 17831 days ago · 3 km deep · 31 km away
  2. 2.421 km NE of Soledad, California · 17831 days ago · 6 km deep · 31 km away
  3. 1.84 km NE of Tres Pinos, California · 17831 days ago · 10 km deep · 17 km away
  4. 2.026 km NE of Greenfield, California · 17832 days ago · 6 km deep · 51 km away
  5. 1.62 km WSW of Ridgemark, California · 17833 days ago · 6 km deep · 8 km away
  6. 1.78 km W of Gilroy, California · 17833 days ago · 4 km deep · 33 km away
  7. 1.621 km NE of Soledad, California · 17833 days ago · 6 km deep · 31 km away
  8. 1.821 km NNE of Soledad, California · 17834 days ago · 9 km deep · 28 km away
  9. 2.022 km NE of San Ardo, California · 17834 days ago · 6 km deep · 91 km away
  10. 2.27 km ENE of Morgan Hill, California · 17834 days ago · 4 km deep · 45 km away
  11. 2.08 km ESE of East Foothills, California · 17835 days ago · 8 km deep · 71 km away
  12. 1.622 km SSW of Los Banos, California · 17835 days ago · 3 km deep · 46 km away
  13. 1.917 km SSE of Tres Pinos, California · 17836 days ago · 10 km deep · 22 km away
  14. 2.47 km E of East Foothills, California · 17837 days ago · 6 km deep · 73 km away
  15. 2.022 km NE of Soledad, California · 17837 days ago · 10 km deep · 32 km away
  16. 2.724 km NE of Greenfield, California · 17838 days ago · 1 km deep · 49 km away
  17. 1.923 km NE of King City, California · 17839 days ago · 3 km deep · 67 km away
  18. 1.523 km ENE of Soledad, California · 17839 days ago · 5 km deep · 44 km away
  19. 1.69 km NE of Corralitos, California · 17839 days ago · 11 km deep · 42 km away
  20. 2.29 km E of Gilroy, California · 17839 days ago · 8 km deep · 28 km away

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Sources

From the USGS Earthquake Hazards Program and its partner networks, event nc1038044. Read Thu, Oct 1, 2026, 6:46 PM UTC.