REAL-TIME DOUBLE-DIFFERENCE EARTHQUAKE LOCATIONS FOR NORTHERN CALIFORNIA


Last updated on Tue Apr 13 09:34:56 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
73548885 2021/04/13 07:25:54.620 38.84150 -122.89676 7.371 0.00 2 1.80 0A.1 tech 3D gE usgs GGF
73548865 2021/04/13 07:03:0.290 38.77313 -122.75753 0.010 0.50 1 0.18 0A.1 tech 3D gE usgs GGF
73548860 2021/04/13 06:19:41.070 36.56423 -121.12144 8.163 2.20 2 0.87 0A.1 tech 3D gE usgs
73548855 2021/04/13 06:05:35.420 38.83124 -122.81768 2.217 0.00 2 0.83 0A.1 tech 3D gE usgs GGF
73548850 2021/04/13 05:51:27.740 38.79688 -122.79891 1.045 0.00 1 3.91 0A.1 tech 3D gE usgs GGF
73548845 2021/04/13 05:48:37.190 38.79225 -122.73310 2.462 0.50 2 0.50 0A.1 tech 3D gE usgs GGF
73548840 2021/04/13 05:43:51.760 38.81797 -122.82575 2.854 0.00 1 0.91 0A.1 tech 3D gE usgs GGF
73548835 2021/04/13 05:39:27.840 40.34635 -121.32975 4.029 1.20 1 1.24 3F.1 tech 3D gE usgs
73548830 2021/04/13 04:08:38.360 38.81819 -122.80530 2.814 0.00 1 0.40 0A.1 tech 3D gE usgs GGF
73548825 2021/04/13 03:46:12.550 38.81920 -122.82144 3.735 0.00 1 1.25 0A.1 tech 3D gE usgs GGF
73548820 2021/04/13 02:48:25.220 38.83401 -122.80826 2.823 0.00 2 0.97 0A.1 tech 3D gE usgs GGF
73548810 2021/04/13 02:03:13.160 38.83877 -122.80720 2.686 0.00 2 0.39 0A.1 tech 3D gE usgs GGF
73548815 2021/04/13 02:02:32.420 37.62966 -122.51434 8.706 0.50 1 2.27 3F.1 tech 3D gE usgs
73548805 2021/04/13 01:03:50.390 35.99148 -120.55033 4.976 1.80 1 0.60 0A.1 tech 3D gE usgs PKF
73548800 2021/04/12 23:36:28.830 37.87100 -122.21320 5.640 0.40 - - 0A.0 tech 3D gE usgs
73548795 2021/04/12 22:33:28.610 40.40170 -121.68080 15.380 0.90 - - 6F.0 tech 3D gE usgs
73548790 2021/04/12 21:50:0.430 38.83411 -122.88432 2.828 0.00 2 0.39 0A.1 tech 3D gE usgs GGF
73548785 2021/04/12 21:42:51.830 38.79300 -122.77706 0.715 0.00 2 0.55 0A.1 tech 3D gE usgs GGF
73548780 2021/04/12 21:16:5.150 38.82026 -122.77835 1.141 0.60 1 0.49 3F.1 tech 3D gE usgs GGF
73548775 2021/04/12 20:41:34.530 37.62812 -122.51460 8.792 1.20 1 2.21 3F.1 tech 3D gE usgs

Events last re/processed:
73548835 2021/04/13 05:39:27.840 40.34635 -121.32975 4.029 1.20 1 1.24 3F.1 tech 3D gE usgs
73546455 2021/04/07 18:22:18.590 36.47124 -121.04613 2.571 1.30 1 1.06 3F.1 tech 3D gE usgs
73548885 2021/04/13 07:25:54.620 38.84150 -122.89676 7.371 0.00 2 1.80 0A.1 tech 3D gE usgs GGF
73546630 2021/04/08 03:48:24.190 38.81864 -122.80465 4.017 1.10 1 0.90 2F.1 tech 3D gE usgs GGF
73548865 2021/04/13 07:03:0.290 38.77313 -122.75753 0.010 0.50 1 0.18 0A.1 tech 3D gE usgs GGF
73546625 2021/04/08 03:45:22.910 38.81865 -122.80290 2.844 1.50 1 0.87 2F.1 tech 3D gE usgs GGF
73548860 2021/04/13 06:19:41.070 36.56423 -121.12144 8.163 2.20 2 0.87 0A.1 tech 3D gE usgs
73548855 2021/04/13 06:05:35.420 38.83124 -122.81768 2.217 0.00 2 0.83 0A.1 tech 3D gE usgs GGF
73548850 2021/04/13 05:51:27.740 38.79688 -122.79891 1.045 0.00 1 3.91 0A.1 tech 3D gE usgs GGF
73548845 2021/04/13 05:48:37.190 38.79225 -122.73310 2.462 0.50 2 0.50 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.