Real-Time Double-Difference Earthquake Catalog for Northern California

Last updated on Thu May 21 21:14:06 UTC 2026 ( Thu May 21 17:14:06 EDT 2026 )

IMPORTANT CHANGE NOTE:
This is a comprehensive update of the previous DD-RT system for Northern California. Main changes are: (1) New DD base catalog with events from 1984-2021. (2) All earthquake depths now with respect to geoid (consistent with USGS locations).

About:
This website displays double-difference hypocenter locations computed in real-time (DD-RT) for earthquakes recorded at the Northern California Seismic Network (NCSN). New earthquakes are automatically cross-correlated and relocated relative to a high-resolution base catalog (1984-2021). For more details see here. This site is updated every 5 minutes.

Faults of interest:
Hayward | Calaveras | SAF Parkfield

Earthquakes of interest:
2023-08-10 M4.3 Parkfield
2025-01-10 M3.6 San Francisco

Archived DDRT solutions:
2022: 01 | 02 | 03 | 04 | 05 | 06 | 07 | 08 | 09 | 10 | 11 | 12
2023: 01 | 02 | 03 | 04 | 05 | 06 | 07 | 08 | 09 | 10 | 11 | 12
2024: 01 | 02 | 03 | 04 | 05 | 06 | 07 | 08 | 09 | 10 | 11 | 12
2025: 01 | 02 | 03 | 04 | 05 | 06 | 07 | 08 | 09 | 10 | 11 | 12
2026: 01 | 02 | 03 | 04 | 05 | 06 | 07 | 08 | 09 | 10 | 11 | 12

Downloads:
DD real-time catalog, Jan 2022 - present
DD base catalog, 1984-2021
Search either catalog here.

Most recent events (events in queue = 0):

Q: Solution quality DX: Shift between DD and network location (km); V: version (CISN.DD)
If Q='-': No DDRT solution computed.
tech: technical information; 3D: 3D viewer; waves: wave plots; USGS: USGS event page
Faults/regions of interest:
HAY = Hayward F; CAL = Calaveras F; PKF = Parkfield; LVC = Long Valley
GGF = Geysers Geothermal Field; MTJ = Mendocino Triple Junction

ID DATE TIME (UTC) LAT LON DEPTH ML Q DX V
75366637 2026/05/21 19:00:8.000 40.37307 -125.09594 0.651 3.80 2 0.87 2A.3 tech 3D waves usgs MTJ
75366627 2026/05/21 18:40:45.550 35.89120 -120.42950 10.060 0.00 - - 0A.0 tech 3D waves usgs PKF
75366622 2026/05/21 18:26:47.260 38.79790 -122.77047 3.513 0.80 1 0.22 0A.3 tech 3D waves usgs GGF
75366617 2026/05/21 17:50:23.660 38.83820 -122.78628 1.907 0.70 1 0.24 0A.3 tech 3D waves usgs GGF
75366612 2026/05/21 17:40:4.090 38.83486 -122.82109 4.004 0.40 2 4.21 0A.3 tech 3D waves usgs GGF
75366607 2026/05/21 17:24:28.530 38.53451 -122.17269 3.260 0.00 2 0.00 0A.3 tech 3D waves usgs
75366587 2026/05/21 15:06:2.510 38.78720 -122.76659 2.810 0.40 2 0.05 0A.3 tech 3D waves usgs GGF
75366582 2026/05/21 14:34:54.760 38.77651 -122.74169 2.334 1.10 1 0.19 0A.3 tech 3D waves usgs GGF
75366572 2026/05/21 14:17:43.620 38.81190 -122.82023 3.314 1.30 1 0.30 0A.3 tech 3D waves usgs GGF
75366557 2026/05/21 14:03:21.780 38.83593 -122.81833 1.989 0.70 1 0.18 0A.3 tech 3D waves usgs GGF
75366552 2026/05/21 13:45:43.780 38.83720 -122.83533 1.836 0.30 1 0.03 0A.3 tech 3D waves usgs GGF
75366547 2026/05/21 13:07:33.330 38.81031 -122.68417 6.395 0.90 2 0.34 0A.3 tech 3D waves usgs GGF
75366532 2026/05/21 11:51:41.200 38.76973 -122.72516 1.377 1.00 2 0.05 0A.3 tech 3D waves usgs GGF
75366527 2026/05/21 11:49:13.350 38.79541 -122.72276 1.888 0.90 2 0.18 0A.3 tech 3D waves usgs GGF
75366522 2026/05/21 11:20:49.930 38.77181 -122.74209 1.980 1.10 1 0.10 0A.3 tech 3D waves usgs GGF
75366517 2026/05/21 11:20:10.680 38.82498 -122.84695 2.357 0.40 1 0.14 0A.3 tech 3D waves usgs GGF
75366512 2026/05/21 11:15:41.740 38.82937 -122.81534 2.152 1.30 2 0.13 0A.3 tech 3D waves usgs GGF
75366507 2026/05/21 10:59:18.200 35.82000 -120.51780 9.820 0.30 - - 0A.0 tech 3D waves usgs
75366502 2026/05/21 10:55:41.920 38.81947 -122.84056 1.992 0.70 2 0.39 0A.3 tech 3D waves usgs GGF
75366497 2026/05/21 10:32:29.250 38.81423 -122.80899 10.297 0.30 2 1.39 0A.3 tech 3D waves usgs GGF

Events last processed:
75366637 2026/05/21 19:00:8.000 40.37307 -125.09594 0.651 3.80 2 0.87 2A.3 tech 3D waves usgs MTJ
75366627 2026/05/21 18:40:45.550 35.89120 -120.42950 10.060 0.00 - - 0A.0 tech 3D waves usgs PKF
75366622 2026/05/21 18:26:47.260 38.79790 -122.77047 3.513 0.80 1 0.22 0A.3 tech 3D waves usgs GGF
75366617 2026/05/21 17:50:23.660 38.83820 -122.78628 1.907 0.70 1 0.24 0A.3 tech 3D waves usgs GGF
75366612 2026/05/21 17:40:4.090 38.83486 -122.82109 4.004 0.40 2 4.21 0A.3 tech 3D waves usgs GGF
75366607 2026/05/21 17:24:28.530 38.53451 -122.17269 3.260 0.00 2 0.00 0A.3 tech 3D waves usgs
75366587 2026/05/21 15:06:2.510 38.78720 -122.76659 2.810 0.40 2 0.05 0A.3 tech 3D waves usgs GGF
75366582 2026/05/21 14:34:54.760 38.77651 -122.74169 2.334 1.10 1 0.19 0A.3 tech 3D waves usgs GGF
75366572 2026/05/21 14:17:43.620 38.81190 -122.82023 3.314 1.30 1 0.30 0A.3 tech 3D waves usgs GGF
75366557 2026/05/21 14:03:21.780 38.83593 -122.81833 1.989 0.70 1 0.18 0A.3 tech 3D waves usgs GGF



____________________________________________________________________________________________________
Data sources: U.S. Geological Survey, Menlo Park; University of California, Berkeley; California Institute of Technology; University of Nevada, Reno; California Division of Water Resources; University of Utah; University of Southern California. Real-time data from the Northern California Seismic Network (NCSN) (parametric) and the Northern California Earthquake Data Center (NCEDC) (waveforms).
Project funded by USGS-NEHRP grants 06HQGR0054, 08HQGR0043, G09AP00018, G10AC00040, G20AP00025.
Website developed and maintained by Felix Waldhauser and Ben Engebreth at LDEO, Columbia University.
[DD-RT Version 3.0.ncsn | Contact:  felixw@ldeo.columbia.edu]