June 16, 1994 Weekly Earthquake Report for Southern California ------------------------------------------------ June 9 - 15, 1994 Prepared by: Kate Hutton, Seismological Laboratory (kate@bombay.gps.caltech.edu) 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, June 9, Pacific Daylight Time, to midnight Wednesday night, June 15, Pacific Daylight Time. We recorded 353 earthquakes this week. We hope readers will excuse the brevity of this week's commentary. It is due to the 9:24 am Landers aftershock this morning (Thursday), preliminary magnitude ML5.0. Watch for details in next week's report. Only two events were reported felt by the public during the past week. One was the week's largest quake, the M4.0 Northridge aftershock on Tuesday night. It was on the eastern edge of the aftershock zone, had a thrust focal mechanism, and was fairly widely felt (at least as far as Pasadena). The other felt quake was a Landers aftershock, M3.1, early the next morning. That quake was about 3 miles north of the larger one this morning. 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 7 hrs, to the Daylight Time listed. Table 1 ------- Date Time N Lat. W Long. Mag ------------------------------------------------------------- 6/9 1:53 am 33 30.0 117 52.9 2.5 6 mi. WSW of Laguna Beach 6/9 3:02 am 34 51.7 116 38.5 2.6 21 mi. E of Barstow 6/9 5:36 am 34 17.6 118 36.3 2.1 5 mi. NW of Northridge 6/9 2:46 pm 35 16.3 118 36.0 2.5 13 mi. NW of Tehachapi 6/9 3:05 pm 34 27.1 120 57.3 2.0 19 mi. WSW of Pt. Arguello 6/9 4:52 pm 34 16.0 118 27.2 2.0 1 mi. SW of San Fernando 6/9 4:57 pm 34 16.3 118 27.8 2.0 " 6/9 10:34 pm 34 21.7 118 36.8 2.0 4 mi. SSW of Magic Mtn. 6/9 11:30 pm 34 56.7 116 49.1 2.1 12 mi. ENE of Barstow 6/10 12:55 am 34 0.5 116 19.1 2.1 10 mi. SE of Yucca Valley 6/10 4:55 am 34 17.5 118 28.7 2.0 2 mi. WNW of San Fernando 6/10 5:39 am 34 58.8 116 56.8 2.1 7 mi. NE of Barstow 6/10 7:50 am 34 16.1 118 24.2 2.1 2 mi. ESE of San Fernando 6/10 9:25 am 34 57.5 116 55.9 2.8 7 mi. NE of Barstow 6/10 4:09 pm 34 16.1 119 23.6 2.1 5 mi. W of Ventura 6/10 4:09 pm 34 12.8 118 34.0 2.0 2 mi. ENE of Canoga Park 6/10 5:12 pm 34 20.1 116 28.1 2.0 15 mi. N of Yucca Valley 6/10 6:11 pm 33 57.6 116 40.5 2.3 6 mi. ENE of Cabazon 6/10 6:26 pm 34 0.9 116 19.4 2.6 10 mi. SE of Yucca Valley 6/11 1:36 am 33 59.2 116 50.8 2.0 4 mi. NNE of Banning 6/11 4:46 am 34 14.6 116 46.4 2.0 4 mi. ESE of Big Bear City 6/11 5:39 am 35 59.9 118 51.1 2.3 10 mi. ESE of Porterville 6/11 8:13 am 34 59.6 117 2.3 2.9 7 mi. N of Barstow 6/11 4:12 pm 34 10.2 116 48.6 2.4 4 mi. N of Mt. San Gorgonio 6/11 4:12 pm 34 19.3 118 29.5 2.0 4 mi. SSE of Newhall 6/11 6:14 pm 34 15.0 118 28.7 2.4 3 mi. SW of San Fernando 6/11 8:11 pm 34 23.6 116 27.2 2.6 18 mi. N of Yucca Valley 6/11 11:05 pm 34 18.4 116 27.0 2.3 13 mi. N of Yucca Valley 6/12 6:51 am 34 17.3 118 27.1 2.1 Under San Fernando 6/12 7:37 am 34 22.1 116 28.6 2.1 17 mi. N of Yucca Valley 6/12 7:42 am 34 16.9 118 26.5 2.2 Under San Fernando 6/12 12:33 pm 35 44.9 117 41.1 2.4 8 mi. N of Ridgecrest 6/12 3:07 pm 36 46.4 118 10.8 2.2 2 mi. SSE of Independence 6/12 5:22 pm 34 17.6 118 33.6 2.6 4 mi. NNW of Northridge 6/12 9:22 pm 34 19.1 116 46.1 2.1 6 mi. NE of Big Bear City 6/13 2:31 pm 34 13.2 118 35.1 2.3 1 mi. NE of Canoga Park 6/13 6:21 pm 36 4.9 117 52.0 3.2 5 mi. ENE of Coso Junction 6/13 6:48 pm 34 22.8 118 38.5 2.0 4 mi. SW of Magic Mtn. 6/13 8:15 pm 34 22.1 116 27.4 2.2 17 mi. N of Yucca Valley 6/13 8:57 pm 34 20.6 118 27.6 2.4 4 mi. NNW of San Fernando 6/14 12:22 am 34 15.1 118 30.9 2.2 1 mi. NE of Northridge 6/14 1:49 am 34 17.8 118 33.3 2.0 4 mi. NNW of Northridge 6/14 5:56 am 34 17.3 116 27.0 2.2 11 mi. N of Yucca Valley 6/14 6:55 am 34 11.7 118 32.6 2.4 2 mi. S of Northridge 6/14 7:14 am 34 19.0 118 35.9 2.1 5 mi. SW of Newhall 6/14 7:27 am 35 41.3 117 33.6 2.0 7 mi. NE of Ridgecrest 6/14 7:50 am 34 23.3 116 27.8 2.3 18 mi. N of Yucca Valley 6/14 1:16 pm 35 41.4 118 4.8 2.5 25 mi. SSW of Coso Junction 6/14 3:59 pm 34 37.6 116 30.5 2.0 27 mi. ENE of Lucerne Valley 6/14 10:59 pm 34 18.6 118 23.9 4.0 3 mi. NE of San Fernando FELT 6/14 11:40 pm 35 44.7 118 1.8 2.5 21 mi. SSW of Coso Junction 6/15 2:16 am 34 20.5 118 34.7 2.4 3 mi. SW of Newhall 6/15 3:14 am 34 14.5 116 46.4 2.1 4 mi. ESE of Big Bear City 6/15 7:13 am 34 20.2 116 28.2 3.1 15 mi. N of Yucca Valley FELT 6/15 8:42 am 34 13.8 118 34.9 2.0 2 mi. NNE of Canoga Park 6/15 8:52 am 35 44.5 118 2.0 2.1 21 mi. SSW of Coso Junction 6/15 10:08 am 34 24.1 120 40.8 3.2 12 mi. S of Pt. Arguello 6/15 10:24 am 33 42.4 116 45.9 2.2 3 mi. SW of Idyllwild 6/15 4:10 pm 35 29.4 118 27.0 2.2 10 mi. S of the town of Lake Isabella 6/15 7:05 pm 34 1.4 116 21.5 2.0 8 mi. SE of Yucca Valley 6/15 7:35 pm 36 32.8 117 47.7 2.5 15 mi. ESE of Lone Pine 6/15 11:05 pm 35 26.7 118 23.6 2.0 13 mi. SSE of the town of Lake Isabella 6/15 11:06 pm 35 26.6 118 23.6 2.2 " ------------------------------------------------------------- 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.