Errors from USGS Location and Magnitude:
EQPROC = 4.7km (2.9 mi)
HYPO2K = 5.3km (3.3 mi)
Magnitude = -0.1
USGS Report:
Date Time Lat Lon Mag Depth Location
-----------------------------------------------------------------------------------
2026/09/12 07:25:55 37.873 -121.800 M3.4 17.9 9 km SW of Brentwood, CA
EQPROC Summary:
3013 2026Sep12 725 56.43 37.9015 -121.8400 16.30 0.61 32.1 70.3 197 7
B054 EHZ PB -- 2026Sep12 726 2.82 P U0 32.1 -0.00
RE9A7 EHZ AM 00 2026Sep12 726 4.37 P D0 42.7 0.00
ADUB1 SHZ PN 01 2026Sep12 726 8.90 P D0 73.7 0.00
B057 EHZ PB -- 2026Sep12 726 7.76 P U0 65.5 0.06
MTUMZ SHZ PN 01 2026Sep12 726 14.44 P D1 83.3 4.15
B058 EHZ PB -- 2026Sep12 726 14.69 PnU1 124.6 -0.98
B073 EHZ PB -- 2026Sep12 726 32.10 PnU3 248.5 0.64
HYPO2K Report:
YEAR MO DA --ORIGIN-- --LAT N- --LON W-- DEPTH-M RMS ERH ERZ XMAG1 FMAG1 PMAG GEOID-DEP
2026-09-12 0725 55.22 37 54.848 121W49.549 37.28 0.34 3.48 2.19 3.46 3.46E 37.25
SOURCE
NSTA NPHS DMIN MODEL GAP ITR NFM NWR NWS NVR REMRKS-AVH N.XMG-XMMAD-T N.FMG-FMMAD-T L F X
7 7 33.4 Emb 199 7 7 5 0 7 5 1.06 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
3.46 5 1.06 E 32 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
B054 PB EHZ -- A 33.4 260 135 PU 62.82 7.60 8.12 0.00 -0.52* 1.05 W 0.478 0.00 57.0 3.47 E
RE9A7AM EHZ 00 A 42.2 121 127 PD 64.37 9.15 9.11 0.00 0.04 1.05 W 0.995 0.00 162 2 4.52 E
B057 PB EHZ -- A 66.2 282 114 PU 67.76 12.54 12.18 0.00 0.36 1.05 W 0.742 0.00 51.0 3.44 E
ADUB1PN SHZ 01 A 75.3 191 111 PD 68.90 13.68 13.42 0.00 0.26 1.05 W 0.868 0.00 123 4.29 E
MTUMZPN SHZ 01 A 84.7 185 108 PD 1 74.44 19.22 14.75 0.00 4.47* 0.00 W 0.000 0.00 3.00 4 0.72XE
B058 PB EHZ -- A125.6 169 54 PU 1 74.69 19.47 19.75 0.00 -0.28 0.79 W 0.915 0.00 41.0 3.29 E
B073 PB EHZ -- A249.5 150 54 PU 3 92.10 36.88 34.90 0.00 1.98* 0.00 W 0.000 0.00 1.00 4