Event Number 2874

M2.6 km ESE of San Ramon, CA - 2025/12/28 13:18:58 37.768 -121.933 M2.6 7.3 4 km ESE of San Ramon, CA at 2025/12/28 13:18:58 UTC / 2025/12/28 05:18:58 PDT

Error Map and Stations Used to Locate Event

Errors from USGS Location and Magnitude:

EQPROC = 39.2km (24.3mi)
HYPO2K = 38.5km (23.9mi) Magnitude = 0.2

USGS Report:

Date       Time       Lat    Lon      Mag    Depth                Location   
-----------------------------------------------------------------------------------
2025/12/28 13:18:58  37.768 -121.933  M2.6   7.3 4 km ESE of San Ramon, CA

EQPROC Summary:

2874 2025Dec28 1319  1.76  37.6343 -122.3441 20.46 0.05 27.1 68.1 184  6
GLFBZ SHZ PN 01 2025Dec28 1319  8.16 P ?2  27.1   0.52
ADUB1 SHZ PN 01 2025Dec28 1319 11.37 P ?1  53.7   0.00
RE9A7 EHZ AM 00 2025Dec28 1319 15.33 P U0  82.3   0.00
ATZ   SHZ PN 01 2025Dec28 1319 15.39 P ?0  82.8   0.00
B057  EHZ PB -- 2025Dec28 1319 10.53 P ?3  47.8   0.00
B058  EHZ PB -- 2025Dec28 1319 19.14 Pn?3 114.6  -0.30

HYPO2K Report:

 YEAR MO DA  --ORIGIN--  --LAT N-  --LON W--  DEPTH-M RMS   ERH   ERZ  XMAG1 FMAG1 PMAG GEOID-DEP
 2025-12-28  1319  1.02  37 38.124 122W20.840 34.15  0.01  1.15  2.10        2.40  2.40E   34.15
                                                                                          SOURCE
 NSTA NPHS  DMIN MODEL GAP ITR NFM NWR NWS NVR REMRKS-AVH  N.XMG-XMMAD-T   N.FMG-FMMAD-T  L F X
    6    6  27.4  Emb  186   7   1   5   0   6                                 4  2.40 E  W W  

 XMAG2-N.XMG2-XMMAD-T-S  FMAG2-N.FMG2-FMMAD-T-S  PREF.MAG-N.PMAG-PRMAD-T DEPDAT NS ZT TYP
                                                     2.40      4  2.40 E      3  5  M CRH
 REGION=                          

 STA NET COM L CR DIST AZM  AN P/S WT   SEC (TOBS -TCAL -DLY  =RES)  WT   SR  INFO  CAL  DUR-W-FMAG-T -AMP-U-PER-W-XMAG-T DE
 GLFBZPN SHZ 01 A 27.4 140 138  P  2   8.16  7.14  7.16 0.00 -0.02  0.71  W  0.759 0.00 15.0   2.11 E                        
 B057 PB EHZ -- A 47.6 337 121  P  3  10.53  9.51  9.50 0.00  0.01  0.36  W  0.980 0.00 25.0   2.68 E                        
 ADUB1PN SHZ 01 A 54.0 142 117  P  1  11.37 10.35 10.33 0.00  0.02  1.07  W  0.368 0.00 53.0   3.42 E                        
 RE9A7AM EHZ 00 A 82.6  83 106  PU    15.33 14.31 14.31 0.00  0.00  1.43  W  0.996 0.00 3.00 4 0.68XE                        
 ATZ  PN SHZ 01 A 83.1 151 106  P     15.39 14.37 14.38 0.00 -0.01  1.43  W  0.895 0.00 83.0 1 3.88 E                        
 B058 PB EHZ -- A115.0 143  54  P  3  19.14 18.12 18.73 0.00 -0.61* 0.00  W  0.000 0.00 1.00 4                               

Event Files: December 2025