REAL-TIME DOUBLE-DIFFERENCE EARTHQUAKE LOCATIONS FOR NORTHERN CALIFORNIA


Last updated on Wed Jun 16 07:35:15 UTC 2021    [DD-RT Version 2.0 | Contact: felixw@ldeo.columbia.edu]

CHANGE NOTE: Events after 2013/10/16 are computed with updated software (v2.0) and base catalog (NCAeqDD.201112.1).

How it works:
This website displays automatic near-real-time double-difference (DD-RT) hypocenter locations for earthquakes recorded in northern California and routinely processed at the Northern California Seismic Network (NCSN). The DD-RT process relocates new earthquakes relative to a high-resolution DD catalog of background seismicity, NCAeqDD, by using differential times between the new event and its neighboring (reference) events in the DD catalog. Routinely determined parametric data of new events, such as phase picks and hypocentral information, are automatically sent to LDEO by the NCSN and waveforms are accessed from the real-time DART server at the Northern California Earthquake Data Center (NCEDC) in Berkeley. Data associated with the reference events are accessed from a locally stored copy of the entire Northern CA seismic archive. See Waldhauser (BSSA, 2009) for more information. This web site is updated every 10 minutes.

Faults of special interest:
Hayward Fault | Calaveras Fault | Parkfield

Earthquakes of special interest:
2020-08-19 M4.0 Willits
2015-08-17 M4.0 Fremont
2014-08-24 M6.0 South Napa
2012-10-21 M5.3 King City
2012-08-06 M4.4 Parkfield
2011-10-20 M4.0 Berkeley

Archived DDRT solutions:
2012: Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2013: Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2014: Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2015: Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2016: Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2017: Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2018: Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2019: Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2020: Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec
2021: Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

Downloads:
Download the real-time double-difference catalog, Jan 2012 - present, here .
Download the double-difference base catalog, 1984-2011, here.
Search either catalog here.

Most recent events:
Events in queue: 0
Q: Quality of DDRT solution; DX: Shift between DD and network location (km); V: version (CISN.DD)
If Q='-': No DDRT solution computed.
tech: link to technical information; 3D: link to 3D viewer; gE: link to google Earth viewer
Faults/regions of special interest:
HAY = Hayward Fault; CAL = Calaveras Fault; PKF = Parkfield; LVC = Long Valley;
GGF = Geysers Geothermal Field; MTJ = Mendocino TJ

EVENT ID DATE TIME (UTC) LAT LON DEPTH ML Q DX V
73577545 2021/06/16 06:41:31.200 38.83846 -122.80758 3.125 0.90 2 0.21 0A.1 tech 3D gE usgs GGF
73577540 2021/06/16 06:10:43.480 37.50571 -121.62217 7.755 0.70 1 0.45 3F.1 tech 3D gE usgs
73577530 2021/06/16 05:35:54.540 39.08101 -123.15479 5.071 1.50 2 0.00 0A.1 tech 3D gE usgs
73577525 2021/06/16 05:34:54.810 38.83318 -122.81941 2.421 0.90 2 0.83 0A.1 tech 3D gE usgs GGF
73577520 2021/06/16 05:32:35.660 38.83481 -122.80919 3.322 0.70 2 0.80 0A.1 tech 3D gE usgs GGF
73577515 2021/06/16 05:28:58.900 38.82138 -122.78946 1.767 0.50 1 0.73 0A.1 tech 3D gE usgs GGF
73577510 2021/06/16 05:06:29.230 38.82603 -122.85855 3.174 0.90 2 0.59 0A.1 tech 3D gE usgs GGF
73577505 2021/06/16 04:58:48.280 38.84159 -122.87851 2.778 0.90 2 1.16 0A.1 tech 3D gE usgs GGF
73577500 2021/06/16 04:56:53.220 38.83387 -122.80505 2.810 0.80 2 0.95 0A.1 tech 3D gE usgs GGF
73577485 2021/06/16 04:12:22.420 38.83431 -122.81768 2.563 1.40 1 0.83 0A.1 tech 3D gE usgs GGF
73577480 2021/06/16 04:02:24.950 37.63692 -118.93193 5.276 0.10 2 0.82 2F.1 tech 3D gE usgs LVC
73577470 2021/06/16 03:48:49.810 37.64426 -118.89120 3.820 -0.10 1 3.60 2F.1 tech 3D gE usgs LVC
73577450 2021/06/16 01:26:50.280 38.83172 -122.81527 1.956 0.90 1 0.66 0A.1 tech 3D gE usgs GGF
73577445 2021/06/16 01:25:50.410 37.50382 -121.62264 7.360 1.00 1 0.49 2F.1 tech 3D gE usgs
73577440 2021/06/16 01:16:25.810 38.82476 -122.85668 2.101 0.90 2 0.30 0A.1 tech 3D gE usgs GGF
73577435 2021/06/16 01:10:19.940 38.83429 -122.82050 2.028 0.40 2 0.52 0A.1 tech 3D gE usgs GGF
73577430 2021/06/16 00:46:55.630 38.81931 -122.78616 2.552 0.30 1 0.92 0A.1 tech 3D gE usgs GGF
73577415 2021/06/16 00:14:29.340 38.76854 -122.70706 2.845 0.50 1 0.81 0A.1 tech 3D gE usgs GGF
73577405 2021/06/15 23:19:1.350 38.82675 -122.80251 3.630 1.40 1 1.28 0A.1 tech 3D gE usgs GGF
73577400 2021/06/15 23:15:41.020 38.82538 -122.85684 2.639 0.00 1 0.86 0A.1 tech 3D gE usgs GGF

Events last re/processed:
73577380 2021/06/15 22:54:15.210 38.82625 -122.80470 3.464 0.50 1 0.92 2F.1 tech 3D gE usgs GGF
73577370 2021/06/15 22:17:42.090 38.82943 -122.80282 2.866 1.80 1 0.96 2F.1 tech 3D gE usgs GGF
73573591 2021/06/13 05:26:5.560 38.83447 -122.81783 2.609 1.20 1 0.73 2F.1 tech 3D gE usgs GGF
73577540 2021/06/16 06:10:43.480 37.50571 -121.62217 7.755 0.70 1 0.45 3F.1 tech 3D gE usgs
73577545 2021/06/16 06:41:31.200 38.83846 -122.80758 3.125 0.90 2 0.21 0A.1 tech 3D gE usgs GGF
73577300 2021/06/15 19:31:31.480 36.56620 -121.11870 8.224 1.10 2 0.69 3F.1 tech 3D gE usgs
73577265 2021/06/15 17:46:7.780 36.57555 -121.03560 9.061 1.90 2 1.56 3F.1 tech 3D gE usgs
73577530 2021/06/16 05:35:54.540 39.08101 -123.15479 5.071 1.50 2 0.00 0A.1 tech 3D gE usgs
73577525 2021/06/16 05:34:54.810 38.83318 -122.81941 2.421 0.90 2 0.83 0A.1 tech 3D gE usgs GGF
73577520 2021/06/16 05:32:35.660 38.83481 -122.80919 3.322 0.70 2 0.80 0A.1 tech 3D gE usgs GGF


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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 under its NEHRP program (06HQGR0054,08HQGR0043).
Website developed and maintained by Felix Waldhauser and Ben Engebreth at LDEO, Columbia University.