SCSNLocal Earthquake – SCSN http://scsn-dev.gps.caltech.edu Southern California Seismic Network Wed, 14 Feb 2018 16:38:47 +0000 en-US hourly 1 https://wordpress.org/?v=4.9.2 01/25/2018, M4.0 near Trabuco Canyon ../../../../index.php/2018/01/25/01-25-2018-m4-0-near-trabuco-canyon/ ../../../../index.php/2018/01/25/01-25-2018-m4-0-near-trabuco-canyon/#respond Thu, 25 Jan 2018 14:54:35 +0000 http://scsn-dev.gps.caltech.edu/?p=2560 ]]>
  • 25 Jan 2018 02:09:56 PST, (33.742, -117.492), depth 11.2km, 12km NE of Trabuco Canyon, California
  • Aftershocks: so far (29 Jan 2018, 08:12AM PST) there have been 27 aftershocks recorded, the largest M3.1 (smallest M0.3). More may be expected in the next few days, the largest expected is approximately 1 magnitude unit smaller than the mainshock. There is a small chance (about 5%) that a larger quake could occur, with the likelihood decreasing over time.
  • There was 1 event during the 3 days prior to the earthquake (within a 10 km radius), with M1.2 (2018/01/22).
  • Plot of seismicity through time, from 3 days before the M4.0 Trabuco Canyon event to approximately 3.5 days after. Top plot shows cumulative earthquake count against time. Bottom plot shows earthquake magnitude against time, the M4.0 event and M3.1 aftershock are plotted as red stars.

  • Historical seismicity: since our records began in 1932 we’ve had 7 events of M4 or greater within 10km of today’s event, the largest was M5.2 (1938/05/31) and the most recent was M4.7 on 02 Sep 2007.
  • Map showing the M4.0 earthquake near Trabuco Canyon (red star) with foreshocks and aftershocks in a 10km radius shown as circles colored by time (blue = early, red = late) and sized by magnitude. Grey stars labelled by magnitude show historic earthquakes. Grey lines show the mapped fault strands in the Elsinore fault zone.

  • Mechanism: the event has a thrust mechanism on a near east-west trending fault plane as shown by the moment tensor below.
    Moment tensor for the M4.0 event on 25 Jan 2018 near Trabuco Canyon.

    The nearest mapped faults to this event are in the Elsinore fault zone, most strands of which usually host strike-slip events. However, the Glen Ivy strands of the Elsinore fault show oblique as well as strike-slip mechanisms (as shown below), and in the region north of Lake Elsinore it is thought the fault may form a restraining bend at depth contributing to uplift of the Santa Ana mountains (Hull & Nicholson, 1992) and consistent with thrust mechanisms such as the 2018/01/25 earthquake.

    Figure from Hull & Nicholson (1992) showing focal mechanisms for selected earthquakes from the Elsinore-Temecula trough. The M4.0 event on 25 Jan 2018 near Trabuco Canyon has been added as a red star, and shows a consistent mechanism with earlier observed earthquakes.

  • Nearby faults: Elsinore fault zone, Glen Ivy section (Glen Ivy South fault) (0.9 km), Elsinore fault zone, Glen Ivy section (Glen Ivy North fault) (1.4 km), Elsinore fault zone, Temecula section (Willard fault) (2.0 km), Elsinore fault zone, Glen Ivy section (Eagle fault) (5.6 km), Elsinore fault zone, Glen Ivy section (Main Street fault) (10.7 km), Elsinore fault zone, Chino section (Chino fault) (12.8 km) and Elsinore fault zone, Temecula section (Wildomar fault) (13.1 km).
  • The ShakeMap (below) shows that ground shaking was strongest to the north and east of the earthquake hypocenter, consistent with stronger shaking being felt in basins and valleys (generally weaker geology, greater chance of amplification effects), and potentially also an effect of source mechanism.
    ShakeMap for the M4.0 event on 25 Jan 2018 near Trabuco Canyon.

  • Links for: USGS earthquake page, ShakeMap, DYFI, waveforms.
  • Visit our special reports page for further information on local notable earthquakes.
  • Below are the waveform data associated with this event, as recorded in our Live Seismograms Feed.

  • References:
    Hull, A.G. & C. Nicholson, 1992. Seismotectonics of the Northern Elsinore Fault Zone, Southern California. Bull. Seismo. Soc. Am. 82 (2) pp. 800-818.
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    01/14/2018, M3.7 near Ludlow ../../../../index.php/2018/01/14/01142018-m3-7-near-ludlow/ ../../../../index.php/2018/01/14/01142018-m3-7-near-ludlow/#respond Sun, 14 Jan 2018 20:06:49 +0000 http://scsn-dev.gps.caltech.edu/?p=2551 ]]>
  • 14 Jan 2018 11:56:11 PST, (34.817, -116.073), depth 4.2km, 13km NE of Ludlow, California.
  • Aftershocks: so far there have been no aftershocks recorded. Some may be expected in the next few days, the largest expected is approximately 1 magnitude unit smaller than the mainshock. There is a small chance (about 5%) that a larger quake could occur, with the likelihood decreasing over time.
  • Historical seismicity: since our records began in 1932 we’ve had 2 events of M4 or greater within 10km of today’s event, the largest was M4.5 (1938/08/18) and the most recent was M4.1 on 09 Nov 1942.
  • Nearby faults: Ludlow fault (10.6 km).
  • Links for: USGS earthquake page, ShakeMap, DYFI, waveforms.
  • Visit our special reports page for further information on local notable earthquakes.
  • Below are the waveform data associated with this event, as recorded in our Live Seismograms Feed. The closest station shown to the event is CI.WWC at approximately 100km, and the furthest is CI.MLAC at more than 400km.

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    01/06/2018, M3.8 near Isla Vista ../../../../index.php/2018/01/07/01062018-m3-8-near-isla-vista/ ../../../../index.php/2018/01/07/01062018-m3-8-near-isla-vista/#respond Sun, 07 Jan 2018 01:43:35 +0000 http://scsn-dev.gps.caltech.edu/?p=2548 ]]>
  • 06 Jan 2018 17:31:10 PST, (34.400, -120.025), depth 2.3km, 15km W of Isla Vista, California
  • Aftershocks: so far there have been no aftershocks recorded. Some may be expected in the next few days, the largest expected is approximately 1 magnitude unit smaller than the mainshock. There is a small chance (about 5%) that a larger quake could occur, with the likelihood decreasing over time.
  • Historical seismicity: since our records began in 1932 we’ve had 4 events of M4 or greater within 10km of today’s event, the largest was M4.8 (2013/05/29) and the most recent was M4.1 on 17 May 2017.
  • Nearby faults: Glen Annie fault (11.1 km) and Mission Ridge fault system, More Ranch section (More Ranch fault) (11.7 km).
  • Links for: USGS earthquake page, ShakeMap, DYFI, waveforms.
  • Visit our special reports page for further information on local notable earthquakes.
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    12/06/2017, M4.0 near Julian ../../../../index.php/2017/12/07/12062017-m4-0-near-julian/ ../../../../index.php/2017/12/07/12062017-m4-0-near-julian/#respond Thu, 07 Dec 2017 02:27:48 +0000 http://scsn-dev.gps.caltech.edu/?p=2529 ]]>
  • A number of felt earthquakes have occurred near Julian, California, four with magnitude three or above:
    • M4.0, 06 Dec 2017 16:33:15 PST, (33.148, -116.480), depth 11.1km, 14km NE of Julian, California
    • M3.0, 06 Dec 2017 16:38:03 PST, (33.150, -116.482), depth 11.1km, 14km NE of Julian, California
    • M3.6, 06 Dec 2017 19:57:38 PST, (33.150, -116.480), depth 11.4km, 14km NE of Julian, California
    • M3.5, 07 Dec 2017 02:32:47 PST, (33.147, -116.478), depth 11.0km, 14km ENE of Julian, California
  • Aftershocks: so far (07 Dec 2017, 08:00AM PST) there have been 76 aftershocks recorded for the M4.0 event, the largest M3.6 (smallest M0.6). More may be expected in the next few days, the largest expected is approximately 1 magnitude unit smaller than the mainshock. There is a small chance (about 5%) that a larger quake could occur, with the likelihood decreasing over time.
  • Cumulative event number against time (top) and magnitude against time (bottom) for the events near Julian on 6-7 December 2017. In the lower plot, red stars mark the four events with magnitude three or above.
  • There were 3 events during the 3 days prior to the earthquake (within a 15 km radius), the largest was M2.6 (2017/12/07).
  • Historical seismicity: since our records began in 1932 we’ve had 9 events of M4 or greater within 10km of today’s event, the largest was M4.7 (1957/01/24) and the most recent was M4.5 on 10 Oct 1984.
  • Nearby faults: Elsinore fault zone, Julian section (Earthquake Valley fault) (3.5 km), Elsinore fault zone, Earthquake Valley fault, Julian section (4.3 km) and Elsinore fault zone, Julian section (Elsinore fault) (10.0 km).
  • Links for: USGS earthquake page, ShakeMap, DYFI, waveforms.
  • Visit our special reports page for further information on local notable earthquakes.
  • Below are the waveform data associated with this event, as recorded in our Live Seismograms Feed. The closest station shown to the event is CI.DGR at approximately 75km, and the furthest is CI.MLAC at more than 500km.

    Below is a playlist of the waveform data associated with this sequence, as recorded in our Live Seismograms Feed. The closest station shown to the event is CI.DGR at approximately 75km, and the furthest is CI.MLAC at more than 500km. More videos may be added as new events occur.

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    11/09/2017, M3.5 near Anza ../../../../index.php/2017/11/10/11092017-m3-5-near-anza/ ../../../../index.php/2017/11/10/11092017-m3-5-near-anza/#respond Fri, 10 Nov 2017 01:56:08 +0000 http://scsn-dev.gps.caltech.edu/?p=2516 ]]>
  • 09 Nov 2017 16:23:30 PST, (33.462, -116.467), depth 7.4km, 22km ESE of Anza, California
  • Aftershocks: so far (09 Nov 2017, 05:53PM PST) there have been 5 aftershocks recorded, the largest M1.5 (smallest M0.8). More may be expected in the next few days, the largest expected is approximately 1 magnitude unit smaller than the mainshock. There is a small chance (about 5%) that a larger quake could occur, with the likelihood decreasing over time.
  • There were 29 events during the 3 days prior to the earthquake (within a 15 km radius), the largest was M3.1 (2017/11/09).
  • Historical seismicity: since our records began in 1932 we’ve had 34 events of M4 or greater with in 10km of today’s event, the largest was M5.6 (2005/06/12) and the most recent was M5.2 on 10 Jun 2016.
  • Nearby faults: San Jacinto fault zone, Anza section (Clark fault) (0.4 km), San Jacinto fault zone, Anza section (0.4 km), San Jacinto fault zone, Coyote Creek section (Coyote Creek fault) (3.2 km), San Jacinto fault zone, Coyote Creek section (3.5 km) and San Jacinto fault zone, Anza section (Buck Ridge fault) (4.3 km).
  • Links for: USGS earthquake page, ShakeMap, DYFI, waveforms.
  • Visit our special reports page for further information on local notable earthquakes.
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    10/26/2017, M3.7 near Avalon ../../../../index.php/2017/10/27/10262017-m3-7-near-avalon/ ../../../../index.php/2017/10/27/10262017-m3-7-near-avalon/#respond Fri, 27 Oct 2017 19:53:00 +0000 http://scsn-dev.gps.caltech.edu/?p=2513 ]]>
  • 26 Oct 2017 16:18:28 PDT, (33.462, -118.183), depth 10.7km, 19km NE of Avalon, California
  • Aftershocks: so far there have been no aftershocks recorded. Some may be expected in the next few days, the largest expected is approximately 1 magnitude unit smaller than the mainshock. There is a small chance (about 5%%) that a larger quake could occur, with the likelihood decreasing over time.
  • Historical seismicity: since our records began in 1932 we’ve had 4 events of M4 or greater within 10km of today’s event, the largest was M4.8 (1988/11/20) and the most recent was M4.8 on 20 Nov 1988.
  • Nearby faults: Coronado Bank fault zone, Coronado Bank-Palos Verdes section (9.8 km), Palos Verdes fault zone, San Pedro shelf section (Palos Verdes fault) (11.0 km) and Santa Cruz_Santa Catalina Ridge fault zone (26.2 km).
  • Links for: USGS earthquake page, ShakeMap, DYFI, waveforms.
  • Visit our special reports page for further information on local notable earthquakes.
  • Below are the waveform data associated with this event, as recorded in our Live Seismograms Feed.

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    10/26/2017, M4.3 near Lompoc ../../../../index.php/2017/10/26/10262017-m4-3-near-lompoc/ ../../../../index.php/2017/10/26/10262017-m4-3-near-lompoc/#respond Thu, 26 Oct 2017 21:55:29 +0000 http://scsn-dev.gps.caltech.edu/?p=2508 ]]>
  • 26 Oct 2017 13:38:51 PDT, (34.435, -120.670), depth 3.1km, 30km SW of Lompoc, California
  • Aftershocks: so far (26 Oct 2017, 02:52PM PDT) there have been 2 aftershocks recorded, the largest M2.1 (smallest M1.5). More may be expected in the next few days, the largest expected is approximately 1 magnitude unit smaller than the mainshock. There is a small chance (about 5%) that a larger quake could occur, with the likelihood decreasing over time.
  • Historical seismicity: since our records began in 1932 we’ve had 4 events of M4 or greater within 10km of today’s event, the largest was M4.7 (1959/10/01) and the most recent was M4.0 on 09 Jan 1989.
  • Nearby faults: Santa Lucia Bank fault zone (9.1 km).
  • Links for: USGS earthquake page, ShakeMap, DYFI, waveforms.
  • Visit our special reports page for further information on local notable earthquakes.
  • Below are the waveform data associated with this event, as recorded in our Live Seismograms Feed.

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    10/24/2017, M3.9 near San Clemente Is ../../../../index.php/2017/10/24/10242017-m3-9-near-san-clemente-is/ ../../../../index.php/2017/10/24/10242017-m3-9-near-san-clemente-is/#respond Tue, 24 Oct 2017 13:40:59 +0000 http://scsn-dev.gps.caltech.edu/?p=2320 ]]>
  • 24 Oct 2017 00:00:51 PDT, (33.173, -118.722), depth 4.8km (fixed), 19km NW of San Clemente Is.
  • Aftershocks: so far there have been no aftershocks recorded. Some may be expected in the next few days, the largest expected is approximately 1 magnitude unit smaller than the mainshock. There is a small chance (about 5%) that a larger quake could occur, with the likelihood decreasing over time.
  • Historical seismicity: since our records began in 1932 we’ve had 1 events of M4 or greater within 10km of today’s event, the largest and most recent was M4.1 on 21 Oct 1932.
  • Nearby faults: San Clemente fault zone (San Clemente fault) (3.5 km) and Santa Cruz_Santa Catalina Ridge fault zone (21.7 km).
  • Links for: USGS earthquake page, ShakeMap, DYFI, waveforms.
  • Visit our special reports page for further information on local notable earthquakes.
  • Below are the waveform data associated with this event, as recorded in our Live Seismograms Feed. The closest stations represented in this display are CI.RPV and CI.DJJ at 70km and 107km away from the epicenter.

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    09/19/2017, M3.7 near Little Lake ../../../../index.php/2017/09/19/09192017-m3-7-event-near-little-lake/ ../../../../index.php/2017/09/19/09192017-m3-7-event-near-little-lake/#respond Tue, 19 Sep 2017 19:42:48 +0000 http://scsn-dev.gps.caltech.edu/?p=2251 ]]>
  • 19 Sep 2017 11:45:43 PDT, (36.020, -117.770), depth 1.8km, 15km NE of Little Lake, California
  • Aftershocks: so far there have been no aftershocks recorded. Some may be expected in the next few days, the largest expected is approximately 1 magnitude unit smaller than the mainshock. There is a small chance (about 5%%) that a larger quake could occur, with the likelihood decreasing over time.
  • There were 19 events during the 3 days prior to the earthquake (within a 15 km radius), the largest was M3.2 (2017/09/19).
  • Historical seismicity: since our records began in 1932 we’ve had 21 events of M4 or greater within 10km of today’s event, the largest was M5.3 (1996/11/27) and the most recent was M4.0 on 15 Feb 2010.
  • Nearby faults: Airport Lake fault zone (0.0 km), Unnamed fault near Coso Basin (4.9 km) and Unnamed fault east of Rose Valley (7.1 km).
  • Links for: USGS earthquake page, ShakeMap, DYFI, waveforms.
  • Visit our special reports page for further information on local notable earthquakes.
  • Below are the waveform data associated with this event, as recorded in our Live Seismograms Feed. The closest station represented in this feed is CI.CLC, 27km away from the epicenter.

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    09/18/2017, M3.6 near Westwood ../../../../index.php/2017/09/19/09182017-m3-6-event-near-westwood/ ../../../../index.php/2017/09/19/09182017-m3-6-event-near-westwood/#respond Tue, 19 Sep 2017 14:14:06 +0000 http://scsn-dev.gps.caltech.edu/?p=2249 ]]>
  • 18 Sep 2017 23:20:44 PDT, (34.087, -118.475), depth 10.5km, 5km NW of Westwood, California
  • Aftershocks: so far (19 Sep 2017, 07:09AM PDT) there has been 1 aftershock recorded, M2.0. More may be expected in the next few days, the largest expected is approximately 1 magnitude unit smaller than the mainshock. There is a small chance (about 5%) that a larger quake could occur, with the likelihood decreasing over time.
  • Historical seismicity: since our records began in 1932 we’ve had 4 events of M4 or greater within 10km of today’s event, the largest was M4.5 (1994/01/19) and the most recent was M4.2 on 02 Jun 2014.
  • Nearby faults: Santa Monica fault (4.7 km), Hollywood fault (6.0 km), Newport-Inglewood-Rose Canyon fault zone, north Los Angeles basin section (10.8 km), Santa Monica fault (offshore) (11.5 km), Charnock fault (12.3 km) and Palos Verdes fault zone, Santa Monica Basin section (Palos Verdes fault) (13.7 km).
  • Links for: USGS earthquake page, ShakeMap, DYFI, waveforms.
  • Visit our special reports page for further information on local notable earthquakes.
  • Below are the waveform data associated with this event, as recorded in our Live Seismograms Feed.The closest stations represented in the feed are CI.DJJ and CI.RPV at 2.9m and 38.7m away from the epicenter respectively.

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