SOUTHERN CALIFORNIA SEISMOGRAPHIC NETWORK A Cooperative Project of Caltech and the U.S. Geological Survey April 11, 1996 Weekly Earthquake Report for Southern California ------------------------------------------------ April 4 - 10, 1996 Prepared by: Nick Scheckel, Seismological Laboratory (kate@bombay.gps.caltech.edu) Lucy Jones, U. S. Geological Survey California Institute of Technology 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, April 4, Universal Time (ie. GMT), to midnight Wednesday night, April 11, Universal Time. In local time, the period of coverage is from 4 p.m., April 4, Pacific Standard Time, to 5 p.m., April 10, Pacific Daylight Time. We detected and processed 370 earthquakes during the 7-day period covered. The largest quake occurring this week was a M3.9 aftershock to the Landers earthquake (M7.3, June 28, 1992). It was felt, Monday afternoon. A quake occurring a couple of hours earlier to that, in the same location, was also felt, a M2.9. A few people in San Fernando woke up early Sunday morning to a M2.6 Northridge aftershock (M6.7, Jan. 17, 1994). A M3.1 quake occurred near Simi Valley about 6 hours later, but no felt calls were reported for that one. The table lists the quakes this week 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 Pacific Daylight Time or 8 hrs to the Pacific Standard Time listed. Table 1 ------- Date Time N Lat. W Long. Mag ------------------------------------------------------------- 4/ 3 5:58 pm 35 44.3 117 37.8 2.6 8 mi. NNE of Ridgecrest 4/ 3 8:21 pm 33 11.3 115 36.1 2.0 2 mi. ENE of Obsidian Butte 4/ 4 2:47 am 34 21.0 116 28.0 2.2 16 mi. N of Yucca Valley 4/ 4 5:08 am 32 58.2 117 49.5 2.5 30 mi. WSW of Oceanside 4/ 4 5:32 am 34 17.0 118 32.6 2.2 2 mi. WNW of Granada Hills 4/ 4 9:10 am 34 28.4 116 30.0 2.0 24 mi. N of Yucca Valley 4/ 4 9:26 am 35 49.6 117 41.9 2.1 14 mi. N of Ridgecrest 4/ 4 6:50 pm 36 3.0 117 43.2 2.3 12 mi. E of Coso Junction 4/ 4 11:26 pm 33 44.3 115 55.1 2.2 14 mi. N of North Shore 4/ 5 12:10 pm 35 45.2 117 38.1 2.1 9 mi. N of Ridgecrest 4/ 5 3:32 pm 36 2.9 117 43.2 2.1 12 mi. E of Coso Junction 4/ 5 5:56 pm 32 31.7 115 16.7 2.3 15 mi. SE of Calexico 4/ 5 10:19 pm 34 7.4 116 23.5 2.0 3 mi. E of Yucca Valley 4/ 6 1:18 am 32 51.3 118 24.3 2.0 4 mi. NW of San Clemente Is. 4/ 6 1:48 am 33 10.6 115 39.1 2.2 Under Obsidian Butte 4/ 6 2:07 am 33 10.4 115 39.2 2.4 1 mi. WNW of Obsidian Butte 4/ 6 2:11 am 33 10.6 115 39.0 2.7 Under Obsidian Butte 4/ 6 8:06 am 33 11.6 115 36.1 2.5 2 mi. NE of Obsidian Butte 4/ 6 8:07 am 33 10.0 115 39.5 2.1 1 mi. W of Obsidian Butte 4/ 6 8:13 am 33 10.1 115 39.1 2.2 Under Obsidian Butte 4/ 6 7:55 pm 32 32.4 115 16.5 2.1 15 mi. SE of Calexico 4/ 7 4:46 am 34 20.4 118 27.5 2.6 4 mi. NNW of San Fernando FELT 4/ 7 9:09 am 35 45.0 117 37.1 2.0 9 mi. NNE of Ridgecrest 4/ 7 11:08 am 34 21.7 118 39.4 3.1 6 mi. NNE of Simi Valley 4/ 7 11:43 am 34 41.8 120 12.0 2.3 5 mi. N of Buellton 4/ 7 3:24 pm 34 22.7 116 27.6 3.0 17 mi. N of Yucca Valley 4/ 7 6:09 pm 34 8.8 117 23.5 2.0 3 mi. NNW of Rialto 4/ 7 10:32 pm 34 20.0 116 54.7 2.2 5 mi. NW of Big Bear City 4/ 8 1:34 am 34 3.7 116 22.5 2.1 5 mi. SE of Yucca Valley 4/ 8 5:57 am 33 56.1 116 18.8 2.3 10 mi. E of Desert Hot Springs 4/ 8 5:58 am 33 56.2 116 18.5 2.0 11 mi. E of Desert Hot Springs 4/ 8 7:06 am 34 0.8 118 21.4 2.1 1 mi. NE of Baldwin Hills 4/ 8 7:48 am 35 56.7 117 5.4 2.1 15 mi. S of Telescope Peak 4/ 8 8:20 am 34 22.7 116 27.7 3.0 17 mi. N of Yucca Valley 4/ 8 9:02 am 34 22.5 116 27.7 2.4 " 4/ 8 9:43 am 34 22.6 116 27.7 2.0 " 4/ 8 10:02 am 34 22.8 116 27.9 2.1 18 mi. N of Yucca Valley 4/ 8 11:37 am 34 22.9 116 27.8 2.0 " 4/ 8 12:36 am 33 45.8 115 43.9 2.5 15 mi. WSW of Eagle Mtn. 4/ 8 12:59 am 32 39.9 116 1.1 2.1 5 mi. SSW of Ocotillo 4/ 8 1:36 pm 34 22.7 116 27.5 2.9 17 mi. N of Yucca Valley FELT 4/ 8 2:47 pm 35 44.3 117 37.9 2.0 8 mi. NNE of Ridgecrest 4/ 8 3:07 pm 32 40.2 115 54.2 2.2 6 mi. SE of Ocotillo 4/ 8 4:46 pm 34 22.6 116 27.6 3.9 17 mi. N of Yucca Valley FELT 4/ 8 4:47 pm 34 22.5 116 27.9 2.0 " 4/ 8 5:02 pm 34 23.1 116 27.7 2.1 18 mi. N of Yucca Valley 4/ 8 5:17 pm 34 22.4 116 27.8 2.4 17 mi. N of Yucca Valley 4/ 8 6:10 pm 34 22.9 116 27.8 2.4 18 mi. N of Yucca Valley 4/ 8 7:16 pm 34 30.3 120 41.0 2.1 5 mi. SSW of Pt. Arguello 4/ 8 7:20 pm 35 49.1 117 32.4 2.0 10 mi. WNW of Trona 4/ 8 7:29 pm 34 11.9 116 23.8 2.0 6 mi. NNE of Yucca Valley 4/ 8 7:42 pm 34 22.0 116 27.9 2.4 17 mi. N of Yucca Valley 4/ 9 12:04 am 33 46.8 116 7.2 2.2 7 mi. NE of Indio 4/ 9 12:04 am 33 46.9 116 6.8 2.2 " 4/ 9 1:19 am 33 57.5 116 59.2 2.5 2 mi. NNW of Beaumont 4/ 9 1:27 am 33 57.5 116 59.0 2.1 2 mi. N of Beaumont 4/ 9 3:06 am 35 6.2 118 18.3 2.3 8 mi. WNW of Mojave 4/ 9 5:14 am 34 21.2 118 44.8 2.4 5 mi. NNW of Simi Valley 4/ 9 5:16 am 34 21.3 118 44.5 2.4 " 4/ 9 5:54 am 35 57.5 117 4.3 2.1 14 mi. S of Telescope Peak 4/ 9 12:42 am 34 22.8 116 27.8 2.0 18 mi. N of Yucca Valley 4/ 9 12:47 am 34 2.1 116 18.6 2.1 7 mi. S of Joshua Tree 4/ 9 3:10 pm 33 20.4 116 12.3 2.1 11 mi. ENE of Borrego Springs 4/ 9 5:45 pm 34 26.5 116 31.8 2.3 22 mi. NNW of Yucca Valley 4/ 9 8:22 pm 35 45.0 117 38.0 2.3 9 mi. NNE of Ridgecrest 4/10 12:40 am 34 21.2 118 37.0 2.0 4 mi. SW of Valencia 4/10 4:07 am 35 6.1 119 7.3 2.6 12 mi. WNW of Wheeler Ridge 4/10 5:45 am 35 44.7 117 37.8 2.4 8 mi. NNE of Ridgecrest 4/10 3:53 pm 33 56.1 116 19.0 2.5 10 mi. E of Desert Hot Springs -------------------------------------------------------------