January 6, 1994 Weekly Earthquake Report for Southern California ------------------------------------------------ December 28, 1993 - January 5, 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 Tuesday morning, December 28, Pacific Standard Time, to midnight Wednesday night, January 5, Pacific Standard Time. The map includes a virtually complete set of earthquakes of M2.0 or larger, plus many smaller ones that happen to have made it through the data processing. There are 378 this time. The seismicity has been fairly quiet over the holidays, with only 378 quakes in the 9 day period. Only 2 quakes inside of our regular reporting area, both Landers aftershocks, had magnitudes of M3.0 or larger. Strangely enough both occurred within the same hour on New Years morning, although neither produced enough public interest to preempt the Rose Parade coverage. A M2.6 last Thursday evening was felt, in Redlands. Both the quakes in the L.A. Basin on New Years evening were too small to attract any attention. The table lists the quakes that were M2.0 or larger in the central part of the coverage area. Only M2.5 and larger events are listed for south of the U.S./Mexico border, and for the Coalinga/Parkfield area. For more information on the latter, see the Northern California Report issued by the U.S.G.S. in Menlo Park. 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 ------------------------------------------------------------- 12/28 3:05 am 33 47.7 118 33.7 2.0 7 mi. W of Palos Verdes Point 12/28 7:19 am 34 55.2 116 54.8 2.3 6 mi. ENE of Barstow 12/28 2:06 pm 34 10.8 116 49.2 2.3 5 mi. N of Mt. San Gorgonio 12/28 6:04 pm 33 43.8 119 26.3 2.0 21 mi. SSE of Santa Cruz Is. 12/29 4:03 am 34 11.8 119 38.1 2.5 13 mi. NNW of Santa Cruz Is. 12/29 4:35 am 34 28.5 116 29.3 2.0 24 mi. N of Yucca Valley 12/29 1:09 pm 34 37.5 116 33.3 2.0 25 mi. ENE of Lucerne Valley 12/29 4:39 pm 35 3.6 118 56.6 2.8 2 mi. N of the I5/99 inter- change 12/29 9:34 pm 34 30.7 116 31.8 2.4 27 mi. N of Yucca Valley 12/30 12:34 am 33 21.3 116 21.0 2.1 7 mi. N of Borrego Springs 12/30 9:08 am 35 38.9 117 37.9 2.3 2 mi. NE of Ridgecrest 12/30 1:22 pm 34 9.0 117 38.0 2.1 5 mi. N of Ontario 12/30 2:41 pm 33 45.8 116 8.5 2.0 5 mi. NE of Indio 12/30 3:50 pm 34 10.1 116 25.1 2.0 3 mi. NNE of Yucca Valley 12/30 6:29 pm 34 24.8 116 28.2 2.1 20 mi. N of Yucca Valley 12/30 9:43 pm 34 1.0 117 12.6 2.6 3 mi. SW of Redlands; FELT 12/30 10:56 pm 34 6.7 117 27.6 2.0 1 mi. W of Fontana 12/31 2:39 am 36 1.0 117 48.0 2.4 8 mi. ESE of Coso Junction 12/31 2:56 am 36 1.0 117 48.0 2.5 " 12/31 7:12 am 34 57.0 116 57.2 2.0 5 mi. NE of Barstow 12/31 5:27 pm 34 12.5 119 38.5 2.3 14 mi. NNW of Santa Cruz Is. 1/1 2:48 am 34 37.3 116 32.9 2.0 25 mi. ENE of Lucerne Valley 1/1 9:30 am 34 54.8 116 55.3 3.0 6 mi. ENE of Barstow 1/1 9:47 am 34 23.3 117 0.9 3.4 5 mi. SW of Lucerne Valley 1/1 10:33 am 34 54.8 116 55.2 2.6 6 mi. ENE of Barstow 1/1 1:31 pm 34 23.3 116 27.3 2.3 18 mi. N of Yucca Valley 1/1 5:52 pm 32 25.4 115 13.3 2.6 23 mi. SE of Calexico 1/1 6:35 pm 33 57.3 118 12.1 2.0 South Gate, 5 mi. N of the I710/91 interchange 1/1 10:02 pm 34 7.0 116 24.3 2.5 2 mi. E of Yucca Valley 1/1 11:34 pm 33 55.7 118 16.7 2.1 3 mi. ESE of Hollywood Park Racetrack 1/2 6:03 am 34 8.6 116 26.4 2.0 1 mi. N of Yucca Valley 1/2 7:02 am 32 58.8 115 54.8 2.5 17 mi. NNE of Ocotillo 1/2 11:09 am 32 15.4 115 12.1 2.6 33 mi. SSE of Calexico 1/2 4:46 pm 34 22.0 116 27.9 2.4 17 mi. N of Yucca Valley 1/2 5:34 pm 34 23.0 116 27.9 2.6 18 mi. N of Yucca Valley 1/2 10:47 pm 34 28.2 116 30.3 2.2 24 mi. N of Yucca Valley 1/3 5:31 am 33 56.3 116 18.5 2.4 11 mi. E of Desert Hot Springs 1/3 12:08 pm 34 15.3 116 26.1 2.1 9 mi. N of Yucca Valley 1/3 12:20 pm 33 30.9 116 30.4 2.4 9 mi. ESE of Anza 1/3 1:00 pm 36 55.5 118 10.9 2.0 8 mi. N of Independence 1/3 2:02 pm 33 30.7 116 30.4 2.9 9 mi. ESE of Anza 1/3 3:39 pm 36 5.1 120 3.6 3.2 17 mi. ESE of Coalinga 1/3 3:39 pm 34 7.5 116 24.9 2.3 1 mi. ENE of Yucca Valley 1/3 6:27 pm 33 31.0 116 30.4 2.1 9 mi. ESE of Anza 1/4 1:00 am 35 36.5 118 14.8 2.0 12 mi. E of the town of Lake Isabella 1/4 1:34 am 34 37.1 116 36.1 2.2 22 mi. ENE of Lucerne Valley 1/4 2:22 pm 34 24.6 117 43.4 2.6 6 mi. WNW of Wrightwood 1/5 1:15 pm 32 23.8 115 22.9 2.5 19 mi. SSE of Calexico 1/5 8:36 pm 35 57.0 117 57.9 2.5 6 mi. S of Coso Junction 1/5 10:49 pm 35 57.1 117 57.9 2.4 " ------------------------------------------------------------- Figure. 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.