March 31, 1994 Weekly Earthquake Report for Southern California ------------------------------------------------ March 24 - 30, 1994 Prepared by: Kate Hutton, Seismological Laboratory (kate@bombay.gps.caltech.edu) Nick Scheckel Lucy Jones, U.S. Geological Survey California Institute of Technology This document is a commentary on current seismic activity. The earthquakes discussed have been detected and processed automatically. All epicenters and magnitudes have been reviewed to exclude obvious blunders; however, they must still be considered preliminary. For further information, please contact the authors or the Caltech Public Relations Office at 818-395-6326. For daily updates, call our Earthquake Information Hotline: 818-395-6977. -------------------------------- This week's Report covers the time period from midnight Thursday morning, March 24, Pacific Standard Time, to midnight Wednesday night, March 30, Pacific Standard Time. There are 424 this week. The rate of seismicity since the Northridge quake is continuing to decline, as expected. Although the Northridge aftershock sequence is now averaging about three M3.0 or larger events per week, this week had none. There was only one felt event this week, a Northridge aftershock that awakened people at 2:13 am last Friday, March 25th. The only M3.0 event for this week went unfelt on Sunday evening (March 27th) at 10:18 pm. It occurred on the southern San Jacinto fault north of Borrego Springs, a common site of small earthquakes. The table lists the quakes that were M2.0 or larger in the central part of the coverage area. Times are local times; if you want Greenwich Mean Time, add 8 hrs, to the Pacific Standard Time listed. Table 1 ------- Date Time N Lat. W Long. Mag ------------------------------------------------------------- 3/24 12:12 am 34 3.5 118 51.7 2.2 4 mi. ENE of Leo Carrillo State Beach 3/24 3:03 am 35 43.7 116 29.9 2.2 21 mi. SW of Shoshone 3/24 4:09 am 34 23.6 116 27.7 2.1 18 mi. N of Yucca Valley 3/24 6:49 am 34 23.0 118 37.3 2.3 3 mi. SSW of Magic Mtn. 3/24 10:04 am 34 23.6 118 37.7 2.3 " 3/24 11:25 am 34 37.5 116 31.9 2.0 26 mi. ENE of Lucerne Valley 3/24 11:52 am 34 22.7 118 38.3 2.1 4 mi. SW of Magic Mtn. 3/24 1:09 pm 34 19.3 119 19.5 2.0 3 mi. NNW of Ventura 3/24 1:42 pm 35 40.7 117 36.6 2.2 5 mi. NE of Ridgecrest 3/24 2:25 pm 33 57.8 116 38.7 2.3 8 mi. W of Desert Hot Springs 3/24 5:58 pm 34 19.2 118 33.4 2.8 4 mi. SSW of Newhall 3/24 6:25 pm 34 12.6 118 28.9 2.0 3 mi. ESE of Northridge 3/24 7:43 pm 35 54.4 120 27.8 2.4 1 mi. WNW of Parkfield 3/24 8:12 pm 33 58.5 117 12.2 2.1 5 mi. SSW of Redlands 3/24 8:13 pm 33 58.4 117 12.2 2.1 5 mi. SSW of Redlands 3/24 11:39 pm 34 21.6 116 27.7 2.6 16 mi. N of Yucca Valley 3/25 2:13 am 34 13.4 118 28.5 2.9 3 mi. ESE of Northridge FELT 3/25 2:14 am 34 12.9 118 28.7 2.3 3 mi. ESE of Northridge 3/25 9:18 am 34 25.1 116 27.1 2.2 20 mi. N of Yucca Valley 3/25 9:58 am 34 20.5 116 26.8 2.1 15 mi. N of Yucca Valley 3/25 11:29 am 34 18.5 118 29.1 2.7 3 mi. NW of San Fernando 3/25 4:01 pm 35 17.9 118 32.7 2.5 12 mi. NNW of Tehachapi 3/25 5:55 pm 34 17.8 118 28.6 2.0 2 mi. WNW of San Fernando 3/25 6:45 pm 34 34.1 116 33.1 2.0 24 mi. ENE of Lucerne Valley 3/25 6:46 pm 34 19.4 116 27.1 2.2 14 mi. N of Yucca Valley 3/25 7:20 pm 34 10.0 116 26.5 2.1 3 mi. N of Yucca Valley 3/26 7:13 am 34 21.2 118 41.7 2.9 5 mi. N of Simi Valley 3/26 10:55 am 34 37.6 116 33.2 2.2 25 mi. ENE of Lucerne Valley 3/26 11:53 am 35 40.6 117 36.7 2.4 4 mi. NE of Ridgecrest 3/26 12:23 pm 34 17.3 116 46.2 2.7 5 mi. ENE of Big Bear City 3/26 3:29 pm 34 17.7 118 27.0 2.0 1 mi. NW of San Fernando 3/26 4:51 pm 33 31.0 116 27.6 2.1 12 mi. ESE of Anza 3/26 7:35 pm 32 51.1 118 0.1 2.1 20 mi. E of SE tip of San Clemente Is. 3/26 10:22 pm 34 14.3 118 30.3 2.1 1 mi. E of Northridge 3/26 10:54 pm 34 22.3 116 28.0 2.0 17 mi. N of Yucca Valley 3/27 3:36 am 34 7.6 116 23.6 2.0 2 mi. E of Yucca Valley 3/27 4:43 am 34 24.2 116 27.9 2.2 19 mi. N of Yucca Valley 3/27 7:11 am 34 36.6 116 36.1 2.2 22 mi. ENE of Lucerne Valley 3/27 10:19 am 35 43.9 117 35.4 2.1 8 mi. NNE of Ridgecrest 3/27 5:24 pm 34 37.5 116 36.5 2.4 22 mi. ENE of Lucerne Valley 3/27 5:26 pm 34 18.3 116 28.9 2.5 13 mi. N of Yucca Valley 3/27 8:20 pm 35 19.1 117 39.5 2.3 21 mi. S of Ridgecrest 3/27 10:18 pm 33 21.0 116 21.5 3.0 6 mi. N of Borrego Springs 3/28 5:54 am 33 34.4 115 54.5 2.6 3 mi. NNE of North Shore 3/28 6:02 am 34 13.6 116 45.7 2.3 5 mi. ESE of Big Bear City 3/28 4:50 pm 32 46.1 115 26.4 2.0 7 mi. NNE of Calexico 3/28 6:04 pm 34 14.3 118 27.2 2.0 3 mi. SSW of San Fernando 3/28 6:43 pm 34 23.7 116 27.5 2.0 19 mi. N of Yucca Valley 3/28 7:19 pm 32 46.1 115 26.5 2.1 6 mi. ESE of El Centro 3/28 7:30 pm 33 14.0 115 39.8 2.1 9 mi. SSE of Bombay Beach 3/28 10:31 pm 34 15.4 116 27.5 2.0 9 mi. N of Yucca Valley 3/29 2:17 am 33 36.6 116 42.1 2.0 4 mi. NNW of Anza 3/29 4:04 am 34 17.5 118 27.9 2.2 1 mi. WNW of San Fernando 3/29 4:11 am 33 14.4 115 40.2 2.0 8 mi. SSE of Bombay Beach 3/29 4:19 am 34 56.3 119 0.0 2.5 6 mi. SSW of the I5/99 interchange 3/29 8:32 am 34 26.1 116 30.4 2.0 22 mi. N of Yucca Valley 3/29 8:37 am 34 12.2 116 25.9 2.0 5 mi. N of Yucca Valley 3/29 9:24 am 34 21.8 118 24.9 2.5 5 mi. NNE of San Fernando 3/29 1:52 pm 32 38.2 115 52.7 2.2 9 mi. SE of Ocotillo 3/29 2:19 pm 34 23.6 118 38.1 2.0 3 mi. SW of Magic Mtn. 3/29 9:11 pm 34 23.0 118 38.4 2.0 4 mi. SW of Magic Mtn. 3/30 6:27 am 34 2.0 116 19.3 2.0 9 mi. SE of Yucca Valley 3/30 6:55 am 34 20.6 118 26.9 2.1 4 mi. N of San Fernando 3/30 10:43 am 34 19.6 118 36.9 2.3 6 mi. SSW of Magic Mtn. 3/30 11:30 am 33 53.0 116 52.8 2.3 2 mi. S of Banning 3/30 1:19 pm 34 19.9 118 28.3 2.0 3 mi. NNW of San Fernando 3/30 3:27 pm 34 17.1 118 27.6 2.1 1 mi. W of San Fernando 3/30 6:29 pm 34 24.5 116 28.1 2.3 20 mi. N of Yucca Valley ------------------------------------------------------------- Figure 1. A map of southern California showing the earthquakes recorded during the past week by the Caltech/USGS Seismic Network. Major faults are marked, as well as the metropolitan areas of Los Angeles (L.A.), Palm Springs (P.S.), San Diego (S.D.), and Santa Barbara (S.B.). The circles denote the earthquakes, the size of the circle indicating the magnitude.