SCSNLocal Earthquake – SCSN http://www.scsn.org Southern California Seismic Network Tue, 21 Aug 2018 17:53:51 +0000 en-US hourly 1 https://wordpress.org/?v=4.9.2 08/14/2018, M4.4 near Aguanga ../../../../index.php/2018/08/15/08-14-2018-m4-4-near-aguanga/ ../../../../index.php/2018/08/15/08-14-2018-m4-4-near-aguanga/#respond Wed, 15 Aug 2018 01:42:19 +0000 http://www.scsn.org/?p=2847 ]]>
  • 14 Aug 2018 18:24:26 PDT, (33.477, -116.803), depth 1.9km, 7km NE of Aguanga, California
  • Aftershocks: so far (16 Aug 2018, 10:48AM PDT) there have been 435 aftershocks recorded, the largest M2.9 (smallest M0.0). 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.
  • There were 95 events during the 3 days prior to the earthquake (within a 10 km radius), the largest was M2.3 (2018/08/12). This area has been experiencing swarm activity for over 2 years (referred to as Cahuilla swarm), seeing elevated seismicity rates since early 2016. This region has hosted earthquake swarms since the 1980s, each lasting for weeks or a few months. The swarm starting early 2016 is the most prolific swarm recorded, with several thousand events observed so far.
  • 2018 seismicity in the region of the Cahuilla swarm as of 15 August 2018. Circles plot individual earthquakes at all magnitudes in the SCSN catalogue, with size indicating magnitude. Events with magnitude 3.0 or greater are shown as red stars. The red line plots the cumulative number of events with magnitude 1.49 or greater.

    Seismicity in the Cahuilla swarm from 1 day before the M4.4 event to approximately 40 hours after. Top plot shows the cumulative event number and the number of events per 20 minutes, both showing the aftershock event rate decay. Bottom plot shows event magnitudes against time.

  • Historical seismicity: since our records began in 1932 we’ve had 13 events of M4 or greater within 10km of today’s event, the largest was M5.6 (2005/06/12) and the most recent was M4.1 on 17 Nov 2008.
  • 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 to the earthquake shown in the view is CI.HMT2 near Anza-Borrego at approximately 30km from the epicenter.

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    07/25/2018, M4.2 near Ensenada ../../../../index.php/2018/07/25/07-25-2018-m4-6-near-ensenada/ ../../../../index.php/2018/07/25/07-25-2018-m4-6-near-ensenada/#respond Wed, 25 Jul 2018 20:42:56 +0000 http://www.scsn.org/?p=2835 ]]>
  • 25 Jul 2018 13:17:56 PDT, (31.950, -116.298), depth 15.8km, 32km ENE of Ensenada, B.C., Mexico
  • 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 42 events of M4 or greater within 10km of today’s event, the largest was M6.8 (1956/02/09) and the most recent was M4.1 on 09 Aug 2011.
  • 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 to the earthquake shown in the view is CI.SDG in San Diego at approximately 120km from the epicenter.

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    07/10/2018, M3.6 near Ontario ../../../../index.php/2018/07/10/07-10-2018-m3-6-near-ontario/ ../../../../index.php/2018/07/10/07-10-2018-m3-6-near-ontario/#respond Tue, 10 Jul 2018 14:30:34 +0000 http://www.scsn.org/?p=2812 ]]>
  • 10 Jul 2018 04:08:37 PDT, (34.010, -117.585), depth 4.3km, 6km SE of Ontario, California
  • Aftershocks: so far (10 Jul 2018, 07:23AM PDT) there have been 5 aftershocks recorded, the largest M2.5 (smallest M0.9). 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 17 events of M4 or greater within 10km of today’s event, the largest was M5.5 (1990/02/28) and the most recent was M4.4 on 15 Jan 2014.
  • Nearby faults: Red Hill-Etiwanda Avenue fault (10.5 km) and Elsinore fault zone, Chino section (Chino fault) (11.0 km).
  • Links for: USGS earthquake page, ShakeMap, DYFI, waveforms.
  • Below are the waveform data associated with this event, as recorded in our Live Seismograms Feed.The closest station to the earthquake shown in the view is CI.RVR in Riverside at approximately 19km from the epicenter.

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    05/30/2018, M3.8 near Thousand Palms ../../../../index.php/2018/05/30/05-30-2018-m3-8-near-thousand-palms/ ../../../../index.php/2018/05/30/05-30-2018-m3-8-near-thousand-palms/#respond Wed, 30 May 2018 19:35:31 +0000 http://www.scsn.org/?p=2783 ]]>
  • 30 May 2018 12:22:05 PDT, (33.924, -116.323), depth 9.5km, 13km NNE of Thousand Palms, California
  • Aftershocks: so far (30 May 2018, 12:33PM PDT) there have been 2 aftershocks recorded, the largest M1.2 (smallest M0.9). 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 1 events during the 3 days prior to the earthquake (within a 10 km radius), the largest was M0.6 (2018/05/30).
  • Historical seismicity: since our records began in 1932 we’ve had 88 events of M4 or greater within 10km of today’s event, the largest was M6.1 (1992/04/23) and the most recent was M4.0 on 06 Aug 2010.
  • Nearby faults: unnamed Fault in the Little San Bernardino Mountains (1.4 km), Blue Cut fault zone (Blue Cut fault) (2.2 km), Eureka Peak fault (5.0 km), San Andreas fault zone, San Bernardino Mountains section (North Branch SAF) (6.6 km), Burnt Mountain fault zone (East Wide Canyon fault) (6.8 km), San Andreas fault zone, San Bernardino Mountains section (6.8 km), Indio Hills fault zone (9.2 km), San Andreas fault zone, San Bernardino Mountains section (South Branch SAF) (9.5 km) and Long Canyon fault (10.9 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 to the earthquake shown in the view is CI.WWC in Palm Springs at approximately 8km from the epicenter.

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    05/08/2018, M4.5 near Cabazon ../../../../index.php/2018/05/08/05-08-2018-m4-5-near-cabazon/ ../../../../index.php/2018/05/08/05-08-2018-m4-5-near-cabazon/#respond Tue, 08 May 2018 13:57:59 +0000 http://www.scsn.org/?p=2711 ]]> A M4.5 earthquake occurred at 4:49 local time this morning (May 8) under the San Bernardino Mountains, near a complex part of the San Andreas fault. Seismologists call this region the “San Gorgonio knot” because so many small faults intersect here and the main San Andreas trace is not clearly defined.

    Historically, this area around Mt. San Gorgonio is the only part of the southern San Andreas fault that produces smaller quakes. Many M3-4 earthquakes have been recorded here. The largest were the M6.0 Desert Hot Springs earthquake in 1948 about 30 miles to the east and the 1986 M5.9 North Palm Springs earthquake that was less than 10 miles east of today’s earthquake.

    The focal mechanism calculated by Caltech and the USGS for this earthquake Moment Tensor Page shows the event happened on a fault that strikes a little north of east-west and that the motion was primarily thrust faulting. This means that the north side moved up and over the lower south side of the fault. This is very similar to the motion we saw in the 1986 North Palm Springs earthquake. (https://authors.library.caltech.edu/48710/.)

    This morning’s M4.5 was felt from San Diego to Los Angeles. More than 10,000 people have reported feeling it at Did you feel it?. The strongest shaking recorded by the instruments is Intensity VI.

    This size earthquake is common in California, happening many times each year somewhere in the state. This is normal activity and has no relationship to the Hawaii eruption.

    Technical information about this earthquake and its aftershocks:

    • 08 May 2018 04:49:34 PDT, (34.017, -116.780), depth 12.9km, 11km N of Cabazon, California.
    • Aftershocks: so far (09 May 2018, 10:40AM PDT) there have been 88 aftershocks recorded, the largest M3.2 (smallest M0.2). 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.
    • Plot of seismicity through time, from 0.5 days before the M4.5 Cabazon event to approximately 1.25 days after. Top plot shows cumulative earthquake count against time. Bottom plot shows earthquake magnitude against time, the M4.5 event and M3.2 aftershock are plotted as red stars.
      Map showing the M4.5 earthquake near Cabazon (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 San Andreas fault zone.
    • Historical seismicity: since our records began in 1932 we’ve had 46 events of M4 or greater within 10km of today’s event, the largest was M6.0 (1986/07/08) and the most recent was M4.4 on 06 Jan 2016.
    • Nearby faults: San Andreas fault zone, San Bernardino Mountains section (3.0 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 to the earthquake shown in the view is CI.WWC in Palm Springs at approximately 35km.

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    05/01/2018, M3.7 near San Clemente Is ../../../../index.php/2018/05/01/05-01-2018-m3-7-near-san-clemente-is/ ../../../../index.php/2018/05/01/05-01-2018-m3-7-near-san-clemente-is/#respond Tue, 01 May 2018 11:48:01 +0000 http://www.scsn.org/?p=2703 ]]>
  • 01 May 2018 04:22:22 PDT, (32.787, -118.443), depth 8.0km, 10km WSW of San Clemente Is.
  • Aftershocks: so far (01 May 2018, 07:20AM PDT) there have been 3 aftershocks recorded, the largest M3.4 (smallest M2.8). 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.
  • 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 M5.8 (1951/12/26) and the most recent was M4.2 on 16 Aug 2001.
  • Nearby faults: San Clemente fault zone (San Clemente fault) (11.0 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 Li
    ve Seismograms Feed.The closest station to the earthquake shown in the view is CI.RPV in Long Beach at approximately 106km.

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    04/25/2018, M3.9 near Borrego Springs ../../../../index.php/2018/04/26/04-25-2018-m3-9-near-borrego-springs/ ../../../../index.php/2018/04/26/04-25-2018-m3-9-near-borrego-springs/#respond Thu, 26 Apr 2018 01:44:49 +0000 http://www.scsn.org/?p=2695 ]]>
  • 25 Apr 2018 18:36:00 PDT, (33.380, -116.298), depth 13.9km, 16km NNE of Borrego Springs, California
  • Aftershocks: so far (26 Apr 2018, 02:27PM PDT) there have been 5 aftershocks recorded, the largest M1.2 (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 4 events during the 3 days prior to the earthquake (within a 10 km radius), the largest was M2.5 (2018/04/25).
  • Historical seismicity: since our records began in 1932 we’ve had 41 events of M4 or greater within 10km of today’s event, the largest was M6.0 (1937/03/25) and the most recent was M5.2 on 10 Jun 2016.
  • Nearby faults: San Jacinto fault zone, Anza section (Clark fault) (1.1 km), San Jacinto fault zone, Anza section (5.8 km), San Jacinto fault zone, Coyote Creek section (6.6 km), San Jacinto fault zone, Coyote Creek section (Coyote Creek fault) (6.8 km) and San Jacinto fault zone, Anza section (Buck Ridge fault) (7.0 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 to the earthquake shown in the view is CI.WWC in Palm Springs at approximately 60km.

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    04/22/2018, M3.9 near Thousand Palms ../../../../index.php/2018/04/23/04-22-2018-m3-9-near-thousand-palms/ ../../../../index.php/2018/04/23/04-22-2018-m3-9-near-thousand-palms/#respond Mon, 23 Apr 2018 01:03:09 +0000 http://www.scsn.org/?p=2683 ]]>
  • 22 Apr 2018 17:46:08 PDT, (33.922, -116.322), depth 8.2km, 13km NNE of Thousand Palms, California
  • Aftershocks: so far (23 Apr 2018, 07:19AM PDT) there have been 7 aftershocks recorded, the largest M2.2 (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.
  • Historical seismicity: since our records began in 1932 we’ve had 85 events of M4 or greater within 10km of today’s event, the largest was M6.1 (1992/04/23) – the Joshua Tree earthquake. The most recent event was M4.0 on 06 Aug 2010.
  • Nearby faults: unnamed Fault in the Little San Bernardino Mountains (1.1 km), Blue Cut fault zone (Blue Cut fault) (2.0 km), Eureka Peak fault (5.4 km), San Andreas fault zone, San Bernardino Mountains section (North Branch SAF) (6.3 km), San Andreas fault zone, San Bernardino Mountains section (6.8 km), Burnt Mountain fault zone (East Wide Canyon fault) (7.1 km), Indio Hills fault zone (8.9 km), San Andreas fault zone, San Bernardino Mountains section (South Branch SAF) (9.3 km) and Long Canyon fault (11.1 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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    04/16/2018, M3.8 near Grapevine ../../../../index.php/2018/04/16/04-16-2018-m3-8-near-grapevine/ ../../../../index.php/2018/04/16/04-16-2018-m3-8-near-grapevine/#respond Mon, 16 Apr 2018 17:11:12 +0000 http://www.scsn.org/?p=2675 ]]>
  • 16 Apr 2018 09:36:48 PDT, (35.043, -119.042), depth 7.7km, 15km NW of Grapevine, 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. The following probability report is based on the statistics of aftershocks typical for California. This is not an exact prediction, but only a rough guide to expected aftershock activity. This probability report may be revised as more information becomes available.
    • STRONG AFTERSHOCKS (Magnitude 5 and larger): at this time (immediately after the mainshock) the probability of a strong and possibly damaging aftershock IN THE NEXT 7 DAYS is less than 10%
    • EARTHQUAKES LARGER THAN THE MAINSHOCK: most likely, the recent mainshock will be the largest in the sequence. However, there is a small chance (APPROXIMATELY 5% TO 10%) of an earthquake equal to or larger than this mainshock in the next 7 days.
    • WEAK AFTERSHOCKS (Magnitude 3 to 5): in addition, up to approximately 2 SMALL AFTERSHOCKS are expected in the same 7-DAY PERIOD and may be felt locally.
  • Historical seismicity: since our records began in 1932 we’ve had 103 events of M4 or greater within 10km of today’s event, the largest was M7.5 (1952/07/21) and the most recent was M4.2 on 22 Sep 2005. Known as the Kern County earthquake, the Mw7.5 event on July 21, 1952 caused widespread damage and was felt across California and Nevada. See the special report on the SCEDC website for more information. Many of the other catalog events in this area are aftershocks of the 1952 Kern County earthquake. The M3.7 earthquake near Bodfish on April 13, 2018, was located approximately 60 km from this event near Grapevine, but is also along the section of fault responsible for the Kern County earthquake.
  • Nearby faults: Wheeler Ridge fault zone (Wheeler Ridge fault) (1.5 km), Pleito fault zone, western Pleito section (Pleito fault) (3.8 km), unnamed faults (1952 earthquake fractures) (4.2 km), Pleito fault zone, eastern Pleito section (Pleito fault) (5.9 km) and Pleito fault zone, western Pleito section (Oak Hill thrust) (13.5 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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    04/13/2018, M3.7 near Bodfish ../../../../index.php/2018/04/13/04-13-2018-m3-7-near-bodfish/ ../../../../index.php/2018/04/13/04-13-2018-m3-7-near-bodfish/#respond Fri, 13 Apr 2018 16:09:30 +0000 http://www.scsn.org/?p=2666 ]]>
  • 13 Apr 2018 08:24:46 PDT, (35.392, -118.545), depth 4.8km, 22km SSW of Bodfish, 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.
  • Nearby faults: White Wolf fault zone (White Wolf fault) (10.3 km) and Edison fault (13.4 km). The White Wolf fault was the site of the largest earthquake in southern California since the Fort Tejon event of 1857. Known as the Kern County earthquake, this Mw7.5 event on July 21, 1952 caused widespread damage and was felt across California and Nevada. See the special report on the SCEDC website for more information.
  • Historical seismicity: since our records began in 1932 we’ve had 90 events of M4 or greater within 10km of today’s event, the largest was M5.6 (1952/07/31) and the most recent was M4.2 on 19 Apr 2014. Many of these events are aftershocks of the 1952 Kern County earthquake.
  • 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 to the event shown is Bakersfield (BAK) at 50km.

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