DISCLAIMER -- THIS IS NOT AN EARTHQUAKE PREDICTION OR WARNING! The commentary provided with these map(s) is for INFORMATIONAL USE ONLY, and SHOULD NOT be construed as an earthquake prediction, warning, or advisory. Responsibility for such warnings rests with the Office of Emergency Services of the State of California. PLEASE REMEMBER -- THESE ARE PRELIMINARY DATA Releasing these summaries on a timely basis requires that the data, analysis, and interpretations presented are PRELIMINARY. Of necessity they can only reflect the views of the seismologists who prepared them, and DO NOT carry the endorsement of the U.S.G.S. Thus while every effort is made to ensure that the information is accurate, nothing contained in this report is to be construed as and earthquake prediction, warning, advisory, or official policy statement of any kind, of the U.S. Geological Survey, or the U.S. Government. FOR QUESTIONS CONCERNING THIS REPORT Send e-mail to michael@andreas.wr.usgs.gov DO NOT SEND EMAIL TO weekly@garlock.wr.usgs.gov It will not be read. Seismicity Report for Northern California, the Nation, and the World for the week of March 28 - April 3, 1996 Stephen R. Walter U.S. Geological Survey 345 Middlefield Rd. MS-977, Menlo Park, CA 94025 San Francisco Bay Area Activity remained light throughout the Bay Area. During the seven-day period ending at midnight on Wednesday, April 3, 1996 the U.S. Geological Survey office in Menlo Park recorded 15 earthquakes of magnitude one (M1) and greater within the San Francisco Bay area shown in Figure 1. Five were as large as M2. This total compares to 19 earthquakes during the previous seven-day period (March 21 - 27 ), six of which were as large as M2.0. With one exception all the M2 earthquakes occurred along the creeping segment of the San Andreas south of San Juan Bautista. Two were in much the same location about 12 miles southeast of Hollister (#1/1). Two others occurred near San Juan Bautista, the first about six miles to the southeast (#2/1), the second practically beneath the town itself (#3/1). The only earthquake as large as M2 in the Bay Area proper was a M2.2 in the northern Livermore Valley about seven miles southwest of Brentwood (#4/1). Northern & Central California Aside from the active swarm in the Long Valley caldera (see below) seismicity remained low throughout the rest of northern and central California. The Cape Mendocino area nearly duplicated last week's level of just one M2 earthquake (#1/2) until a M3.0 early Wednesday morning returned things closer to normal (#6/2). As usual, the Geysers geothermal area produced the most activity in the Coast Ranges, although a M2.2 occurred on the northern Maacama fault about 14 miles north of Willits (#2/2) and a M2.0 occurred near the central Rogers Creek fault just southeast of Santa Rosa (#4/2). Elsewhere, activity was limited to a trio of M2 events on the creeping San Andreas north of the Pinnacles (#3/2) and a pair of M3 aftershocks in the Markleeville area (#5/2). Long Valley Caldera An active swarm, which began with a M3.9 earthquake on Friday, March 29 has produced more than 1400 earthquakes to date. Activity peaked on Saturday and Sunday with over 40 events per hour; it has dropped to the current rate of less than 10 per hour (Thursday). Twenty earthquakes were larger than M3.0 and three were as large as M4.0, the largest a M4.2 Monday evening that was felt as far away as Bishop. Many of the larger quakes have been felt in Mammoth Lakes although no damage has been reported. Most earthquakes were located at depths of about nine kilometers beneath the airport and an equal distance east-southeast of Mammoth Lakes (#1/3). No measurable ground deformation was detected during the swarm. USA Seismicity (March 24 - April 4) The National Earthquake Information Center reported only a few notable earthquakes in the United States during the past week, aside from the Long Valley activity discussed above. Two M3 earthquakes occurred in the southern Yucca Valley area of southern California early this week (#1/4). On Tuesday morning a M2.9 occurred northeast of Seattle that was felt in the towns of Carnation and North Bend (#2/4). More remote was an active swarm in the Fox Islands area of the eastern Aleutian archipelago (2/5). The swarm included several M5 events and one M6.2, all of which were felt at Nikolski. The Planet Earth (March 24 - April 4) A Mb5.6 earthquake struck a rural area of central Ecuador last Thursday, killing at least 62 people, injuring 58, and leaving several thousand homeless (#3/5). Most of the deaths occurred in Pujili where 70% of the town was reported to have been destroyed. Considerable damage was done to homes, bridges, and water pipes in Cotopaxi, Pastaza, and Tungurahua Provinces south of the capital city of Quito. The quake caused landslides near the city of Salcedo and left the nearby town of Latacunga without electricity and phone service. The earthquake was felt throughout much of Ecuador. Other notable earthquakes on the planet include a Ms5.8 west of Macquarie Island (#1/5), a Ms6.0 in the Santa Cruz Islands region (#4/5), a pair of M5.7's in the northern Molucca Sea (#5/5), and a Mb5.5 along the Mariana trench south of the Mariana Islands (#6/5). Table 1. Northern & Central California Seismicity (M>1.0) (Long Valley seismicity is not complete) --ORIGIN TIME (UT)-- -LAT N-- --LON W-- DEPTH N N RMS ERH ERZ DUR YR MON DA HRMN SEC DEG MIN DEG MIN KM RD S SEC KM KM REMKS MAG 96 MAR 28 806 29.23 37 37.30 118 51.04 9.03 7 .02 .8 .9 SMO 1.3 96 MAR 28 1201 13.40 38 50.01 122 49.91 1.61 7 .06 .5 1.1 GEY 1.3 96 MAR 28 1359 24.73 38 48.26 122 48.28 1.63 22 .11 .3 .4 GEY 2.4 96 MAR 28 1545 27.19 40 16.78 124 25.87 22.66 18 .07 1.4 .3 MEN 2.4 96 MAR 28 1816 9.12 38 49.33 122 48.20 4.64 17 .06 .3 .5 GEY 2.2 96 MAR 28 2351 56.51 38 51.26 122 49.42 0.24 8 .04 .4 1.4 GEY 1.0 96 MAR 29 49 28.88 38 55.01 122 37.54 4.33 10 .34 .9 3.0 KON 1.9 96 MAR 29 817 31.18 38 50.92 122 47.51 1.89 12 .06 .3 .9 GEY 1.6 96 MAR 29 951 6.47 39 36.94 123 23.18 7.68 15 .16 .4 .9 MAA 2.2 96 MAR 29 1107 51.35 37 10.64 121 40.63 4.99 12 .06 .3 .8 SCV 1.5 96 MAR 29 1140 32.91 36 36.92 121 13.25 4.55 26 .07 .3 .6 PIN 2.1 96 MAR 29 1724 56.92 38 49.21 122 47.61 4.70 13 .10 .4 .8 GEY 2.0 96 MAR 29 1754 23.40 38 47.87 122 44.84 0.75 8 .04 .3 1.0 GEY 1.5 96 MAR 29 1814 49.40 37 37.47 118 51.36 9.04 27 .11 .4 .6 SMO 3.9 96 MAR 29 1827 5.44 37 36.06 118 53.15 0.02 7 .25 1.6 2.1 SHE * 2.5 96 MAR 29 1828 38.21 37 39.65 118 53.76 7.86 7 .05 .6 .8 DOM 1.3 96 MAR 29 1843 26.12 37 38.27 118 48.41 18.12 7 .06 2.2 3.8 HCF 1.4 96 MAR 29 1846 43.88 37 37.36 118 51.66 6.87 7 .10 .9 1.4 SMO 1.2 96 MAR 29 1847 59.81 38 47.48 122 46.66 2.10 12 .04 .3 .6 GEY 1.8 96 MAR 29 1912 1.85 37 37.99 118 51.29 7.19 7 .13 1.4 1.1 SMO 1.0 96 MAR 29 1929 35.76 37 37.17 118 51.92 7.57 7 .07 1.8 3.7 SMO 1.1 96 MAR 29 1955 30.91 37 38.92 118 52.40 5.19 11 .46 1.3 3.0 SMO 1.4 96 MAR 29 2053 15.19 37 37.33 118 51.39 8.52 25 .11 .4 .6 SMO 3.6 96 MAR 29 2102 11.28 37 37.13 118 51.37 8.28 7 .02 1.0 .7 SMO 1.1 96 MAR 29 2109 28.08 37 37.00 118 50.95 9.17 7 .02 .8 .9 SMO 1.2 96 MAR 29 2131 38.23 36 3.92 120 36.13 9.95 10 .06 .7 .8 SLA 1.5 96 MAR 30 55 21.27 37 37.60 118 51.10 8.32 7 .10 2.2 1.2 SMO 1.0 96 MAR 30 116 46.82 37 39.82 118 51.51 4.38 7 .07 .9 1.4 DOM 1.1 96 MAR 30 124 5.11 36 35.57 121 1.49 11.01 8 .15 1.0 1.9 PAN 1.3 96 MAR 30 148 41.95 37 37.97 118 51.42 7.92 7 .02 1.1 .6 SMO 1.4 96 MAR 30 232 19.37 37 37.71 118 51.25 8.52 17 .06 .4 .6 SMO 3.2 96 MAR 30 431 56.47 37 36.78 118 50.97 9.53 7 .02 .9 1.1 SMO 1.0 96 MAR 30 519 7.33 36 28.11 121 2.57 5.70 7 .03 .5 1.2 BIT 1.0 96 MAR 30 539 39.32 38 48.84 122 48.48 4.38 9 .02 .3 .6 GEY 1.4 96 MAR 30 541 56.67 37 38.65 118 56.09 8.53 7 .03 .8 1.4 SMO 1.4 96 MAR 30 550 10.97 37 36.55 118 51.00 8.81 7 .02 1.0 2.1 SMO 1.0 96 MAR 30 557 29.72 37 37.62 118 51.59 8.27 25 .10 .3 .6 SMO 3.5 96 MAR 30 607 42.55 37 37.64 118 51.32 8.04 7 .02 .8 .8 SMO 1.2 96 MAR 30 614 23.39 37 37.82 118 51.67 8.57 26 .13 .4 .6 SMO 3.5 96 MAR 30 637 50.71 37 36.75 118 50.76 9.98 7 .02 1.2 1.1 SMO 1.7 96 MAR 30 649 27.21 37 37.64 118 51.81 8.75 18 .08 .6 .8 SMO 3.4 96 MAR 30 811 32.96 37 35.99 118 51.92 12.25 7 .13 1.6 2.0 MOR 1.2 96 MAR 30 847 44.31 39 58.10 123 45.83 4.96 7 .12 .8 2.6 MAA 1.8 96 MAR 30 1027 35.36 37 37.09 118 51.20 7.89 7 .03 .8 .7 SMO 1.0 96 MAR 30 1132 31.43 36 0.91 120 33.72 5.20 10 .07 .6 1.0 SLA 1.6 --ORIGIN TIME (UT)-- -LAT N-- --LON W-- DEPTH N N RMS ERH ERZ DUR YR MON DA HRMN SEC DEG MIN DEG MIN KM RD S SEC KM KM REMKS MAG 96 MAR 30 1246 30.53 38 49.32 122 47.67 5.42 13 .09 .3 .6 GEY 1.9 96 MAR 30 1258 27.69 38 49.29 122 47.73 5.75 9 .09 .6 1.0 GEY 1.2 96 MAR 30 1338 49.96 37 37.81 118 51.14 7.06 7 .11 .8 1.0 SMO 1.0 96 MAR 30 1354 15.24 37 37.68 118 50.02 10.14 7 .06 1.1 2.0 HCF 1.1 96 MAR 30 1358 53.34 37 37.54 118 52.09 8.55 25 .08 .3 .6 SMO 3.6 96 MAR 30 1406 39.21 37 38.22 118 53.73 24.76 7 .14 1.7 5.0 SMO 2.0 96 MAR 30 1430 19.19 38 49.27 122 48.00 3.68 9 .02 .3 .7 GEY 1.3 96 MAR 30 1443 13.98 37 38.61 118 52.16 7.07 7 .06 .6 .6 SMO 1.2 96 MAR 30 1507 1.11 37 38.19 118 53.10 4.29 10 .34 1.5 2.0 SMO 1.9 96 MAR 30 1522 23.79 37 37.45 118 51.57 7.94 25 .10 .3 .5 SMO 4.0 96 MAR 30 1526 29.27 37 39.32 118 52.84 24.63 7 .05 1.3 2.7 DOM 1.7 96 MAR 30 1541 13.70 38 49.38 122 47.77 3.91 7 .02 .4 .8 GEY 1.0 96 MAR 30 1604 43.48 37 5.48 121 53.53 10.29 15 .07 .3 1.0 LOM 1.4 96 MAR 30 1606 21.38 37 37.04 118 51.59 5.64 7 .04 .6 1.0 SMO 1.4 96 MAR 30 1623 12.26 36 41.89 121 19.64 2.75 41 .11 .2 .4 STN 2.1 96 MAR 30 1709 4.22 37 37.54 118 51.36 7.57 7 .01 .9 1.7 SMO 1.2 96 MAR 30 1716 14.98 37 5.28 121 53.40 9.95 28 .11 .3 .6 LOM 1.7 96 MAR 30 1725 9.02 37 37.70 118 51.89 6.70 7 .02 1.0 .7 SMO 1.3 96 MAR 30 1731 24.76 36 7.48 120 5.69 6.37 8 .12 1.2 .7 COA 1.8 96 MAR 30 1739 7.89 37 37.79 118 51.91 7.00 7 .04 1.3 .8 SMO 1.4 96 MAR 30 1819 15.02 37 40.09 118 55.33 28.19 10 .33 2.4 6.0 DOM 2.6 96 MAR 30 1854 27.25 37 38.54 118 52.53 6.95 7 .02 1.6 2.0 SMO 1.2 96 MAR 30 1857 35.89 37 37.02 118 50.92 8.28 7 .02 .8 .7 SMO 1.9 96 MAR 30 1907 47.05 37 37.56 118 52.15 7.00 7 .04 .4 .8 SMO 1.3 96 MAR 30 1915 35.09 37 37.85 118 52.05 0.02 19 .44 1.0 2.3 SMO * 2.3 96 MAR 30 1921 3.14 37 38.09 118 52.20 6.58 7 .01 .8 1.8 SMO 1.2 96 MAR 30 1945 55.79 37 40.65 118 51.17 2.29 8 .42 2.8 6.8 DOM 1.1 96 MAR 30 2031 6.04 37 38.35 118 52.65 7.24 7 .05 .8 .6 SMO 1.1 96 MAR 30 2041 31.22 37 38.24 118 51.82 8.48 7 .05 .8 1.7 SMO 1.2 96 MAR 30 2151 57.10 38 49.13 122 48.10 20.18 11 .38 2.2 1.8 GEY 1.5 96 MAR 30 2221 29.88 37 37.61 118 51.29 6.51 23 .08 .3 .5 SMO 3.5 96 MAR 30 2223 22.48 37 37.58 118 51.41 7.96 7 .02 1.1 1.6 SMO 1.4 96 MAR 30 2247 34.02 37 37.52 118 51.90 6.50 7 .02 1.5 .6 SMO 1.2 96 MAR 30 2301 51.22 37 38.89 118 53.66 8.17 7 .29 1.5 2.5 SMO 1.3 96 MAR 30 2315 18.53 37 37.60 118 51.92 7.04 23 .10 .3 .6 SMO 4.0 96 MAR 30 2353 25.82 37 36.00 118 52.68 11.61 10 .35 2.8 2.3 SHE 1.7 96 MAR 31 6 32.19 37 38.13 118 52.05 7.60 7 .11 .7 1.9 SMO 1.4 96 MAR 31 22 32.56 37 40.36 118 52.03 0.02 9 .48 2.2 3.1 DOM * 1.0 96 MAR 31 33 10.24 37 37.27 118 52.38 8.97 7 .03 1.9 1.6 SMO 1.0 96 MAR 31 103 27.49 37 38.12 118 56.81 6.45 7 .07 1.1 1.5 SMO 1.3 96 MAR 31 200 14.36 37 37.30 118 52.36 6.94 19 .07 .3 .5 SMO 3.4 96 MAR 31 235 19.84 37 37.51 118 52.48 6.57 7 .04 .6 .7 SMO 1.7 96 MAR 31 235 44.30 37 37.46 118 52.64 9.92 22 .12 .4 .7 SMO 3.9 96 MAR 31 239 32.02 37 37.81 118 53.36 3.82 11 .38 1.3 3.8 SMO 2.5 96 MAR 31 327 33.61 37 37.18 118 51.59 8.13 7 .04 .7 .9 SMO 1.1 --ORIGIN TIME (UT)-- -LAT N-- --LON W-- DEPTH N N RMS ERH ERZ DUR YR MON DA HRMN SEC DEG MIN DEG MIN KM RD S SEC KM KM REMKS MAG 96 MAR 31 521 16.32 37 37.10 118 50.92 7.18 7 .02 .6 .7 SMO 1.2 96 MAR 31 543 27.68 37 38.38 118 52.37 9.90 7 .05 .9 1.9 SMO 1.5 96 MAR 31 604 19.81 37 38.15 118 53.35 4.67 7 .15 1.4 .8 SMO 1.1 96 MAR 31 614 58.55 37 38.46 118 51.16 0.02 13 .35 1.0 1.9 SMO * 1.7 96 MAR 31 628 54.33 37 36.91 118 50.74 8.62 7 .04 .8 1.0 SMO 1.0 96 MAR 31 707 13.16 37 38.44 118 52.85 1.09 7 .06 .3 .6 SMO 1.2 96 MAR 31 719 27.05 37 37.27 118 51.54 9.21 7 .02 1.9 .9 SMO 1.1 96 MAR 31 736 16.89 37 37.22 118 51.58 7.53 7 .03 .6 .9 SMO 1.2 96 MAR 31 743 31.37 38 49.28 122 47.62 5.28 13 .10 .4 .8 GEY 1.5 96 MAR 31 747 58.87 36 32.56 121 3.06 8.32 10 .08 .8 1.4 BVL 1.4 96 MAR 31 806 25.83 36 32.60 121 3.27 7.92 9 .07 .5 1.2 BVL 1.2 96 MAR 31 820 25.93 37 37.14 118 51.72 6.92 25 .08 .3 .5 SMO 3.4 96 MAR 31 907 22.24 37 38.49 118 51.46 9.64 7 .06 1.7 1.9 SMO 1.0 96 MAR 31 913 35.50 36 1.04 120 33.67 4.97 11 .07 .6 .8 SLA 1.6 96 MAR 31 940 58.13 36 37.07 121 13.09 4.53 60 .09 .2 .4 PIN 2.7 96 MAR 31 1010 6.10 37 37.25 118 50.46 7.57 7 .01 1.4 .6 SMO 1.2 96 MAR 31 1107 28.59 38 47.38 122 46.40 2.96 10 .06 .3 1.5 GEY 1.4 96 MAR 31 1108 3.97 38 47.51 122 46.55 2.52 10 .03 .3 .6 GEY 1.4 96 MAR 31 1122 44.85 38 47.54 122 46.54 2.37 10 .03 .3 .6 GEY 1.4 96 MAR 31 1244 1.82 37 36.89 118 51.00 8.52 7 .06 .9 .9 SMO 1.6 96 MAR 31 1340 36.08 36 39.03 121 16.36 6.47 20 .05 .2 .6 STN 1.8 96 MAR 31 1409 35.87 37 37.28 118 51.84 6.82 23 .09 .3 .5 SMO 3.3 96 MAR 31 1516 29.94 36 30.12 121 5.05 4.32 11 .04 .4 1.0 BIT 1.4 96 MAR 31 1539 23.15 37 38.04 118 51.59 7.52 7 .08 .5 1.1 SMO 1.0 96 MAR 31 1547 42.27 38 25.19 122 40.11 5.26 24 .42 .7 1.9 ROG 2.0 96 MAR 31 1649 28.22 38 48.77 122 48.41 4.43 10 .08 .4 .9 GEY 1.7 96 MAR 31 1701 40.77 38 48.06 122 46.66 3.58 8 .04 .3 2.4 GEY 1.4 96 MAR 31 1716 6.15 37 37.33 118 50.91 7.63 12 .44 1.5 2.3 SMO 1.2 96 MAR 31 1739 21.94 36 34.04 120 22.16 4.69 7 .37 6.828.4 JQN - 3.0 96 MAR 31 1918 6.71 37 37.59 118 52.58 7.41 22 .11 .4 .6 SMO 3.5 96 MAR 31 1927 38.43 37 37.26 118 52.53 7.40 21 .10 .4 .6 SMO 3.7 96 MAR 31 1933 55.53 37 39.52 118 52.82 5.45 7 .22 1.1 2.0 DOM 1.2 96 MAR 31 1936 13.14 38 48.35 122 48.27 3.24 8 .02 .3 .6 GEY 1.2 96 MAR 31 1952 57.94 36 46.06 121 29.08 7.18 45 .21 .4 .7 SJB 2.0 96 MAR 31 2003 32.28 37 39.42 118 53.11 8.45 13 .46 1.5 3.0 DOM 1.9 96 MAR 31 2109 8.18 37 35.93 118 50.66 9.33 7 .07 3.3 3.4 MOR 1.5 96 MAR 31 2142 57.85 37 37.76 118 51.54 6.81 7 .04 .9 1.7 SMO 1.0 96 MAR 31 2154 20.77 37 37.71 118 50.92 7.36 7 .11 .8 1.1 SMO 1.3 96 APR 1 26 29.86 38 48.35 122 48.12 3.67 29 .13 .2 .6 GEY 2.5 96 APR 1 36 22.70 37 38.91 118 54.02 3.67 7 .05 .5 .8 SMO 1.0 96 APR 1 215 19.53 38 50.47 122 49.53 2.12 8 .06 .4 1.1 GEY 1.2 96 APR 1 320 42.85 38 47.87 122 48.16 7.55 10 .07 .4 .9 GEY 1.6 96 APR 1 407 51.35 37 37.10 118 51.22 7.33 24 .08 .3 .5 SMO 3.3 96 APR 1 413 36.48 37 36.92 118 51.53 10.08 22 .08 .3 .7 SMO 3.9 96 APR 1 547 43.43 36 28.29 121 2.28 4.94 48 .07 .2 .8 BIT 2.8 --ORIGIN TIME (UT)-- -LAT N-- --LON W-- DEPTH N N RMS ERH ERZ DUR YR MON DA HRMN SEC DEG MIN DEG MIN KM RD S SEC KM KM REMKS MAG 96 APR 1 947 32.73 36 50.64 121 35.15 7.64 57 .18 .3 .5 SJB 2.3 96 APR 1 957 19.11 37 38.48 118 56.37 6.92 7 .03 .5 1.0 SMO 1.1 96 APR 1 1014 12.14 37 38.36 118 56.27 7.98 7 .08 1.5 3.9 SMO 1.0 96 APR 1 1052 7.62 37 34.95 118 51.92 7.99 7 .05 1.6 2.3 MOR 1.6 96 APR 1 1054 46.64 36 58.70 121 37.68 1.20 15 .23 .5 3.9 SAR 1.2 96 APR 1 1131 44.53 37 37.52 118 52.96 7.47 7 .07 .7 1.0 SMO 1.6 96 APR 1 1153 14.60 37 36.70 118 50.73 8.71 7 .05 1.0 .9 SMO 1.5 96 APR 1 1404 11.19 37 37.38 118 52.83 7.76 7 .06 .8 .9 SMO 1.3 96 APR 1 1531 26.40 37 37.33 118 51.52 6.92 7 .03 1.3 .6 SMO 1.1 96 APR 1 1558 30.26 37 20.23 118 39.41 5.01 14 .31 1.924.6 KAI - 1.8 96 APR 1 1832 15.15 36 16.71 121 43.49 5.46 18 .08 .7 1.5 SUR 1.9 96 APR 1 1918 11.31 38 49.44 122 47.88 4.05 8 .03 .4 .9 GEY 1.2 96 APR 1 1948 35.99 36 58.36 121 37.22 2.50 8 .05 .4 1.8 SAR * 1.0 96 APR 1 2008 33.46 37 37.71 118 52.17 9.65 7 .07 1.1 1.4 SMO 1.0 96 APR 1 2331 2.83 38 42.52 119 36.28 0.04 39 .11 2.6 3.7 WAK * 3.0 96 APR 2 5 20.09 37 37.41 118 52.53 8.08 7 .02 .7 .8 SMO 1.7 96 APR 2 150 7.69 37 37.49 118 51.45 7.12 19 .04 .3 .5 SMO 4.2 96 APR 2 154 0.12 37 37.08 118 50.63 10.23 7 .06 3.0 5.0 SMO 1.6 96 APR 2 226 14.73 37 37.45 118 52.43 8.01 7 .06 1.0 1.5 SMO 1.5 96 APR 2 238 28.06 40 26.58 124 10.33 27.59 8 .08 .7 1.7 MEN 1.9 96 APR 2 402 3.32 38 47.06 122 45.65 2.18 11 .03 .3 .6 GEY 1.5 96 APR 2 429 35.37 37 37.92 118 51.97 7.03 7 .06 .9 1.8 SMO 1.0 96 APR 2 442 32.93 37 37.06 118 52.02 6.77 7 .03 .7 .6 SMO 1.3 96 APR 2 521 38.42 37 38.04 118 52.79 5.82 7 .04 .6 .9 SMO 1.2 96 APR 2 529 11.99 37 37.08 118 51.02 7.81 7 .02 .5 .9 SMO 1.3 96 APR 2 542 40.61 37 54.05 121 58.54 10.62 12 .07 .4 1.1 CON 1.3 96 APR 2 612 1.62 37 38.32 118 51.15 7.77 7 .02 1.7 2.3 SMO 1.1 96 APR 2 739 19.91 38 49.37 122 47.52 5.50 9 .09 .5 .9 GEY 1.3 96 APR 2 749 17.17 37 36.65 118 51.97 9.43 7 .05 2.0 .7 SMO 1.2 96 APR 2 759 29.69 38 49.40 122 47.90 4.14 9 .02 .3 .8 GEY 1.5 96 APR 2 906 52.88 36 43.38 121 12.10 4.52 8 .09 .9 1.7 PAI 1.0 96 APR 2 907 48.25 37 5.98 121 30.77 8.49 24 .05 .4 .6 CYN 1.4 96 APR 2 1127 5.85 37 37.32 118 51.75 9.36 7 .02 .9 .9 SMO 1.3 96 APR 2 1239 36.91 38 46.31 122 43.81 2.41 28 .12 .2 .5 GEY 2.3 96 APR 2 1509 50.45 37 31.86 118 25.76 8.26 13 .07 .4 .9 CHV 1.8 96 APR 2 1647 6.51 37 51.57 121 47.79 15.76 25 .09 .4 .5 GRN 2.2 96 APR 2 1733 22.82 37 37.17 118 51.03 5.29 7 .01 .4 .6 SMO 1.2 96 APR 2 1956 40.81 38 42.21 119 37.93 3.50 13 .26 2.1 2.7 WAK * 3.1 96 APR 2 2120 36.45 37 38.16 118 50.99 6.93 7 .06 1.4 1.1 SMO 1.0 96 APR 2 2208 16.31 37 37.87 118 52.00 6.62 7 .06 .9 .8 SMO 1.0 96 APR 3 42 57.88 37 38.71 118 52.42 0.02 7 .23 .9 1.0 SMO * 2.5 96 APR 3 122 25.11 37 37.73 118 50.98 8.41 7 .11 1.1 1.3 SMO 1.0 96 APR 3 148 19.40 37 38.28 118 51.30 7.69 7 .10 1.1 1.1 SMO 1.1 96 APR 3 209 23.14 37 38.31 118 52.62 4.94 7 .07 .5 1.6 SMO 1.6 96 APR 3 233 56.23 38 47.37 122 46.31 2.66 8 .03 .3 .8 GEY 1.5 --ORIGIN TIME (UT)-- -LAT N-- --LON W-- DEPTH N N RMS ERH ERZ DUR YR MON DA HRMN SEC DEG MIN DEG MIN KM RD S SEC KM KM REMKS MAG 96 APR 3 235 8.66 37 38.10 118 51.27 7.48 7 .05 1.0 1.4 SMO 1.0 96 APR 3 239 37.98 38 47.55 122 45.45 2.21 7 .03 .3 .9 GEY 1.2 96 APR 3 559 45.24 39 25.45 123 17.42 5.51 7 .11 .8 1.2 MAA 1.8 96 APR 3 751 7.89 37 38.65 118 51.35 6.40 7 .11 1.9 1.1 SMO 1.0 96 APR 3 803 28.89 37 37.91 118 52.39 6.03 7 .01 1.2 2.1 SMO 1.0 96 APR 3 915 55.67 40 25.76 125 8.36 5.10 42 .23 2.1 4.8 MEN 3.0 96 APR 3 1002 48.42 37 37.76 118 52.21 6.47 7 .05 1.1 1.8 SMO 1.0 96 APR 3 1129 44.94 37 38.87 118 52.40 8.33 7 .03 .8 1.1 SMO 1.0 96 APR 3 1327 48.26 37 38.92 118 56.15 6.63 7 .01 .7 1.1 SMO 1.4 96 APR 3 1328 30.28 37 39.08 118 56.68 6.56 7 .05 1.0 1.3 SMO 1.5 96 APR 3 1404 17.01 37 39.13 118 56.95 0.04 10 .38 .8 1.3 SMO * 2.0 96 APR 3 1404 47.69 37 38.93 118 56.21 6.40 7 .02 .6 1.2 SMO 1.2 96 APR 3 1407 31.44 37 38.85 118 56.11 6.58 7 .01 .6 1.2 SMO 1.4 96 APR 3 1435 8.95 37 38.24 118 51.91 7.66 7 .04 1.0 1.5 SMO 1.5 96 APR 3 1501 59.59 38 49.24 122 47.99 3.75 11 .02 .3 .7 GEY 1.6 96 APR 3 1530 5.83 37 38.84 118 49.85 12.75 7 .03 1.7 3.0 HCF 1.0 96 APR 3 1533 28.12 36 49.41 121 16.98 7.91 25 .06 .2 .6 QUI 1.5 96 APR 3 1624 0.25 36 41.54 121 19.23 4.66 51 .09 .2 .4 STN 2.5 96 APR 3 1804 16.71 37 37.01 118 57.59 16.34 7 .16 1.9 2.4 SHE 1.1 96 APR 3 1915 27.16 38 49.07 122 48.16 3.60 7 .04 .4 .8 GEY 1.3 96 APR 3 1947 4.16 37 37.52 118 53.09 6.05 7 .04 .9 1.1 SMO 1.0 96 APR 3 2053 34.68 37 38.32 118 52.53 7.48 7 .05 1.0 1.3 SMO 1.0 96 APR 3 2247 47.42 37 40.07 118 51.03 3.31 7 .19 .9 2.4 DOM 1.0 96 APR 4 41 35.25 36 48.30 121 32.59 7.96 9 .07 .6 .9 SJB 1.4 96 APR 4 251 54.84 38 49.39 122 47.71 4.50 8 .02 .4 .9 GEY 1.2 96 APR 4 413 41.19 38 48.83 122 48.44 2.96 8 .03 .3 2.7 GEY 1.4 96 APR 4 427 13.02 38 48.76 122 48.55 4.23 7 .02 .4 .8 GEY 1.3 96 APR 4 730 11.15 37 39.06 118 53.22 4.42 7 .10 1.2 1.9 DOM 1.1 TABLE 2. Data from National Earthquake Information Center (NEIC) UTC TIME LAT LONG DEP GS MAGS SD STA REGION AND COMMENTS HRMNSEC MB Msz USED --------------------------------------------------------------------------- MAR 24 004632.4 16.212N 119.409E 33N 4.4 0.7 28 LUZON, PHILIPPINE ISLANDS 024143.1* 9.494S 112.958E 70* 4.0 1.3 18 SOUTH OF JAWA, INDONESIA 030005.3 52.061N 29.993W 10G 4.4 1.0 42 NORTHERN MID-ATLANTIC RIDGE 082424.1 0.536N 30.153E 10G 4.8 1.1 33 UGANDA 105343.5 8.790N 126.716E 33N 4.7 0.9 34 MINDANAO, PHILIPPINE ISLANDS 132318.5* 14.214S 166.399E 33D 4.4 1.0 17 VANUATU ISLANDS 141715.5? 14.93 S 174.65 W 33N 4.6 1.6 30 SAMOA ISLANDS REGION 142638.5* 45.046N 153.100E 33N 4.6 1.6 44 EAST OF KURIL ISLANDS 194522.1% 13.593N 121.047E 33N 4.1 1.1 11 MINDORO, PHILIPPINE ISLANDS 205123.4 51.303N 178.742E 33N 4.3 1.1 34 RAT ISLANDS, ALEUTIAN ISLANDS 213645.5* 3.513S 145.860E 33N 4.2 1.6 15 NEAR N COAST OF NEW GUINEA, PNG. 221815.2* 55.352S 146.729E 10G 4.2 1.5 11 WEST OF MACQUARIE ISLAND 221903.8* 55.231S 146.233E 10G 5.2 5.8 1.5 18 WEST OF MACQUARIE ISLAND MAR 25 013938.4* 40.080N 32.629E 33N 3.6 1.5 15 TURKEY 023622.0* 31.200N 142.311E 33N 3.9 1.0 18 SOUTH OF HONSHU, JAPAN 024544.0 68.941N 16.635W 10G 3.8 1.2 27 ICELAND REGION 033518.2 8.774N 93.789E 33N 4.3 1.0 26 NICOBAR ISLANDS, INDIA 035147.1 44.410N 149.670E 33N 4.5 1.0 42 KURIL ISLANDS 050053.5 9.014N 126.440E 88* 4.7 1.2 48 MINDANAO, PHILIPPINE ISLANDS 055243.1* 9.019N 126.834E 33N 4.1 0.9 14 MINDANAO, PHILIPPINE ISLANDS 061248.9% 9.038N 126.713E 42D 4.0 1.0 17 MINDANAO, PHILIPPINE ISLANDS 063122.0 33.177N 73.384E 23* 4.5 0.8 28 PAKISTAN 065720.8 63.232N 150.613W 131 4.3 0.9 18 CENTRAL ALASKA 075148.4 8.933N 126.586E 90* 4.5 1.2 29 MINDANAO, PHILIPPINE ISLANDS 092408.7 4.406S 102.914E 33N 4.6 0.8 27 SOUTHERN SUMATERA, INDONESIA 100056.5* 4.853N 95.665E 33N 4.0 1.1 18 NORTHERN SUMATERA, INDONESIA 101233.5 33.263N 137.937E 319 4.0 1.2 34 NEAR S. COAST OF HONSHU, JAPAN 111004.8* 27.941N 130.275E 28 4.0 0.9 17 RYUKYU ISLANDS 134409.5% 10.647N 126.301E 33N 4.2 0.9 10 PHILIPPINE ISLANDS REGION 140146.8 0.790S 136.053E 41* 4.7 1.1 33 IRIAN JAYA REGION, INDONESIA 182421.5* 0.708S 135.271E 33N 4.0 1.5 10 IRIAN JAYA REGION, INDONESIA 203142.4 51.620N 16.177E 10G 3.8 0.9 24 POLAND. ML 4.2 (VIE), 4.0 (MOX). 203414.8% 51.786N 30.162W 33N 4.0 1.0 12 NORTHERN MID-ATLANTIC RIDGE 225032.3? 21.98 S 171.21 E 33N 3.9 1.0 7 LOYALTY ISLANDS REGION MAR 26 015156.6? 25.92 S 179.75 E 497? 4.5 1.5 17 SOUTH OF FIJI ISLANDS 030414.8* 43.909N 149.275E 44D 3.9 0.8 14 EAST OF KURIL ISLANDS 065849.1* 10.264S 80.331W 36D 4.0 1.2 14 OFF COAST OF PERU 080457.4* 68.985N 17.849W 10G 3.7 1.1 9 ICELAND REGION 083024.9 30.639N 79.128E 45D 4.5 0.8 36 XIZANG-INDIA BORDER REGION 091626.9* 6.250S 105.095E 33N 4.3 0.9 18 SUNDA STRAIT 095608.8? 18.09 S 178.01 W 550G 4.1 1.0 13 FIJI ISLANDS REGION 103504.5* 2.816S 122.541E 33N 4.2 1.2 14 SULAWESI, INDONESIA 104832.6 7.141S 155.588E 33N 4.6 0.9 29 SOLOMON ISLANDS 111445.2? 3.49 S 150.47 E 33N 4.0 0.5 8 NEW IRELAND REGION, P.N.G. 121537.7? 42.84 S 83.79 E 10G 4.3 1.4 11 MID-INDIAN RIDGE 123008.9* 21.739S 174.762W 33N 4.4 1.0 16 TONGA ISLANDS 135813.4* 50.063N 77.057E 33N 4.1 1.1 19 EASTERN KAZAKHSTAN 162134.1? 7.26 S 144.89 E 33N 4.0 1.2 7 NEAR S COAST OF NEW GUINEA, PNG. 185944.4? 21.30 S 69.00 W 100G 4.1 0.7 8 CHILE-BOLIVIA BORDER REGION 205811.0* 1.004S 136.860E 33N 4.8 0.9 21 IRIAN JAYA REGION, INDONESIA 214218.4* 9.178S 119.360E 116? 4.1 1.3 17 SUMBA REGION, INDONESIA 225830.7 44.319N 15.443E 33N 1.2 81 NORTHWESTERN BALKAN REGION. ML 4.6 (VIE), 4.1 (ROM). MD 4.3 (TRI). 231312.0? 18.37 S 71.35 W 90? 4.0 1.3 12 OFF COAST OF NORTHERN CHILE MAR 27 025650.6? 33.21 S 178.08 W 33N 4.5 0.8 10 SOUTH OF KERMADEC ISLANDS 031146.1? 20.45 S 177.79 W 500G 4.2 1.2 15 FIJI ISLANDS REGION 033347.7% 28.742N 51.999E 33N 4.0 0.8 17 SOUTHERN IRAN 040724.1? 8.68 S 108.73 W 10G 4.1 1.0 15 CENTRAL EAST PACIFIC RISE 040849.9? 8.77 S 109.35 W 10G 4.0 0.9 7 CENTRAL EAST PACIFIC RISE 062754.0% 22.086N 142.939E 300G 3.6 0.5 9 VOLCANO ISLANDS REGION 065342.7% 28.518S 177.504W 57D 4.2 0.9 12 KERMADEC ISLANDS REGION 070519.8 31.709N 40.869W 10G 4.3 1.1 39 NORTHERN MID-ATLANTIC RIDGE 072634.8% 45.107N 149.987E 39D 3.9 0.8 17 KURIL ISLANDS 090805.7% 31.712S 76.647E 10G 4.1 1.0 12 MID-INDIAN RIDGE 091441.0* 34.780N 27.489E 33N 3.9 0.9 11 EASTERN MEDITERRANEAN SEA 145652.0 52.445N 168.764W 33N 4.7 1.4 57 FOX ISLANDS, E. ALEUTIANS. 153845.9 52.474N 168.732W 33N 4.9 1.3 69 FOX ISLANDS, E. ALEUTIANS. 224812.1 40.157N 142.622E 47D 4.1 1.3 32 NEAR EAST COAST OF HONSHU, JAPAN MAR 28 005447.4* 18.557N 106.393W 33N 4.2 1.2 33 OFF COAST OF JALISCO, MEXICO 014822.7 52.398N 168.609W 33N 5.1 5.0 1.3 156 FOX ISLANDS, E. ALEUTIANS. ML 5.2 (PMR). Felt (IV) at Nikolski. 015618.7 52.330N 168.700W 33N 5.0 1.2 106 FOX ISLANDS, E. ALEUTIANS. Felt. 060914.5 54.278N 165.810W 33N 4.2 0.9 37 FOX ISLANDS, E. ALEUTIANS. ML 4.5 (PMR). Felt on Akutan. 062325.1* 44.273N 149.854E 33N 4.0 1.0 20 KURIL ISLANDS 095249.3 43.334N 146.978E 33N 5.2 0.8 124 KURIL ISLANDS 112621.9 52.472N 168.579W 33N 5.0 4.7 1.3 120 FOX ISLANDS, E. ALEUTIANS. Felt. 120310.2 52.456N 168.589W 33N 4.9 1.3 105 FOX ISLANDS, E. ALEUTIANS. Felt. 141344.5* 9.677S 114.117E 77* 4.6 1.4 28 SOUTH OF BALI, INDONESIA 175320.9 24.160N 122.186E 33N 4.8 1.2 49 TAIWAN REGION 192713.3 53.017N 168.913W 33N 4.5 1.0 33 FOX ISLANDS, E. ALEUTIANS 195107.7 52.409N 168.771W 33N 5.6 5.5 1.3 163 FOX ISLANDS, E. ALEUTIANS. Felt. 203637.7 43.421N 146.954E 33N 4.1 1.3 34 KURIL ISLANDS 213249.9 52.467N 168.767W 33N 5.4 5.1 1.3 132 FOX ISLANDS, E. ALEUTIANS. Felt. 225250.3 52.316N 168.472W 33N 4.6 1.4 49 FOX ISLANDS, E. ALEUTIANS. 230350.0 0.967S 78.689W 33N 5.6 5.2 0.9 157 ECUADOR. At least 19 people killed, 58 injured, several thousand homeless and considerable damage and destruction to homes, bridges and water pipes in Cotopaxi, Pastaza and Tungurahua Provinces. Landslides blocked several roads in the epicentral area. Minor damage (VI) at Ambato, Latacunga and San Miguel de Salcedo. Felt (IV) at Quito; (III) at Ibarra; (II) at Cuenca and Guayaquil. Felt in many parts of Ecuador. MAR 29 032857.0* 24.167N 122.364E 33N 5.3 5.5 1.1 41 TAIWAN REGION 181449.7 37.605N 118.814W 5G 0.8 75 CALIFORNIA-NEVADA BORDER. ML 4.0 MAR 30 125600.2 52.427N 168.634W 33N 5.4 1.3 83 FOX ISLANDS, E. ALEUTIANS. Felt strongly at Nikolski. 130517.3 52.534N 168.727W 33N 6.0 6.2 1.3 115 FOX ISLANDS, E. ALEUTIANS. Mw 6.2 (GS), 6.3 (HRV). Felt strongly at Nikolski. 151413.1* 42.885N 146.841E 45D 5.1 1.1 16 OFF COAST OF HOKKAIDO, JAPAN 152224.8 37.613N 118.863W 5G 1.1 105 CALIFORNIA-NEVADA BORDER. ML 4.0 231636.8 44.454N 149.166E 33N 5.3 0.9 66 KURIL ISLANDS 232217.1* 44.532N 149.155E 33N 5.2 0.9 29 KURIL ISLANDS MAR 31 013931.5* 9.994S 160.686E 64D 5.2 0.7 36 SOLOMON ISLANDS 234142.8 10.991S 165.391E 33N 5.4 6.0 0.7 63 SANTA CRUZ ISLANDS. Mw 6.0 (GS) APR 01 034302.1 16.593N 95.711W 58D 5.2 0.7 71 OAXACA, MEXICO 050609.0 14.608N 93.516W 33N 5.2 1.0 56 NEAR COAST OF CHIAPAS, MEXICO 061052.0 14.464N 93.422W 33N 5.3 1.0 64 NEAR COAST OF CHIAPAS, MEXICO 080802.5 31.501N 73.480E 43D 5.6 4.9 0.8 30 PAKISTAN 084835.3 34.181N 116.451W 10G 0.8 27 SOUTHERN CALIFORNIA. ML 2.9 213753.0* 2.455S 77.582W 33N 4.7 0.8 17 PERU-ECUADOR BORDER APR 02 030402.6* 11.241S 165.588E 33N 5.3 5.5 0.9 18 SANTA CRUZ ISLANDS. Mw 5.6 (GS). 034659.8 33.699N 115.930W 10G 0.9 25 SOUTHERN CALIFORNIA. ML 3.3 172916.0& 47.680N 121.910W 23 9 WASHINGTON. . MD 2.9 (SEA). Felt at Carnation and North Bend. 185034.8* 2.964N 126.136E 33N 5.7 5.4 1.1 24 NORTHERN MOLUCCA SEA. Mw 5.6 APR 03 013937.2 33.706N 115.953W 10G 0.8 24 SOUTHERN CALIFORNIA. ML 3.0 APR 04 054558 Q 12.3 N 143.6 E 10G 5.5 1.0 51 SOUTH OF MARIANA ISLANDS 111119 Q 3.0 N 126.3 E 33N 5.7 0.8 35 TALAUD ISLANDS, INDONESIA Note: Computer users can get faster access to the Weekly Seismicity Reports in any of three ways: 1. World-Wide-Web (WWW) access: http://quake.wr.usgs.gov 2. Anonymous FTP access: quake.wr.usgs.gov (in pub/www/QUAKES/WEEKREPS) 3. Email Access: (send email to michael@andreas.wr.usgs.gov) Notes for Table 1: Origin time in the list is in GMT, in the text and on maps it is in local time. N RD: is the number of readings used to locate the event. N S: is the number of S waves in N RD. RMS SEC: is the root mean squared residual misfit for the location is seconds, the lower the better, over 0.3 to 0.5 seconds is getting bad, but this is machine, not hand timed, data. ERH: is the estimated horizontal error in kilometers. ERZ: is the estimated vertical error in kilometers. N FM: is the number of readings used to compute the magnitude. REMKS: obtuse region codes that denote the velocity model used to locate the event. DUR MAG: is the magnitude as determined from the duration of the seismograms, not the amplitude. Sort of like going to echo canyon and measuring how loud your yell is by counting echos. FIG: denotes the figure/event number in the maps posted separately.