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 July 17- 23, 1997 Stephen R. Walter U.S. Geological Survey 345 Middlefield Rd. MS-977, Menlo Park, CA 94025 San Francisco Bay Area During the seven-day period ending at midnight on Wednesday, July 23, 1997 the U.S. Geological Survey office in Menlo Park recorded 16 earthquakes of magnitude one (M1) and greater within the San Francisco Bay area shown in Figure 1. Only one was as large as M2.0. This total compares to 13 earthquakes during the prior seven-day period (July 10 - 16), one of which was as large as M2. The only notable earthquake of the week occurred just after noon last Thursday and was mentioned in last week's summary. The M4.1 earthquake occurred close to the southern end of the Sargent fault, about three miles southwest of Gilroy (#1/1). It was felt throughout the San Jose area, as far north as Redwood City, and south at least as far as Salinas. No damage was reported from the earthquake. Five small (M1) aftershocks had occurred over the next two days, the largest a M1.8 just before noon on Saturday. The only other earthquake of note was a M1.8 on the northern Concord fault late Monday morning (#2/1). Northern & Central California Activity during the past week was centered primarily in the northern part of the state. The week began with a M2.4 last Thursday evening in the northern Sacramento Valley about eight miles east of Redding (#1/2). It was followed by a pair of M2.3 shocks over the next four days, the first late Sunday night, the second late Tuesday afternoon. A cluster of five M2 earthquakes occurred northeast of Cottonwood over a 27 hour period beginning early Saturday morning (#2/2). Activity on the Mendocino fracture zone included a pair of M2's just west of Petrolia and a M3.3 on Wednesday that was located about 14 miles west of the town (#4/2). On Monday afternoon a M3.5 occurred near the coast about 14 miles southwest of Eureka (#8/2). the following day a 25-km-deep M4.0 earthquake occurred beneath the central Klamath Mountains about 25 miles west of Weaverville (#9/2). It was reported felt at Blue Lake and Willow Creek. Activity in the central Coast Range was limited to a pair of M2's at the Geysers, the largest a M2.7 (#3/2), and a M2.8 near the San Andreas fault about three miles southeast of Point Arena (#5/2). The only earthquakes as large as M2 in central California were a M2.0 on the San Andreas just north of The Pinnacles National Monument (#1/2) and a M2.2 in the southern Sierra Nevada about 18 miles southeast of Porterville (#6/2). Long Valley Caldera The activity along the southwest side of the resurgent dome that began on July 8 declined to just two events as large as M1.5, the largest a M2.1 on Wednesday evening (3/3). To the east a cluster of small earthquakes occurred last Thursday near the Fish Hatchery, the largest of these a M3.4 that may have been felt locally (#1/3). The only earthquake of note south of the caldera was a M2.3 south of Mt. Morrison (#2/3). USA Seismicity (July 15 - 22) Data provided by the National Earthquake Information Center showed a fairly quiet week in the lower 48 states. Outside of California the largest earthquake reported was a M3.5 along the Tennessee/Georgia border (#2/4). Other earthquakes of note: a M2.6 in the Oregon Cascade Mountains just northwest of Mt. Jefferson (#1/4) and a M2.8 in the Seattle area (#3/4). The Planet Earth (July 15 - 22) For a change the eastern Pacific margin was most active during the past week. A M5.8 near the coast of central Chile was widely felt in the vicinity, as was a M5.5 aftershock (#1/5). To the northeast, a M6.0 occurred along the Argentina/Bolivia border that was felt as far away as the northern Chilean coastal towns of Antofagasta and Tocopilla (#4/5). The largest earthquake of the week occurred off the coast of Guerrero, Mexico that was felt in Guerrero and Oaxaca and as far away as Mexico City (#2/5). Table 1. Northern & Central California Seismicity (M>1.0) --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 97 JUL 17 715 21.69 37 36.72 118 48.61 5.70 7 .04 .6 1.3 HCF 1.3 97 JUL 17 1017 0.00 37 30.50 118 51.14 6.05 9 .05 1.0 1.5 MOR 1.2 97 JUL 17 1201 4.75 37 28.32 118 47.03 10.85 18 .06 .7 .8 MOR 1.5 97 JUL 17 1238 48.74 36 38.49 121 15.30 4.28 37 .06 .2 .5 STN 2.0 97 JUL 17 1355 2.12 37 38.15 118 51.55 5.60 15 .08 .4 .6 SMO 1.6 97 JUL 17 1359 36.79 37 38.25 118 51.61 5.42 14 .08 .4 .6 SMO 1.4 97 JUL 17 1403 10.17 37 38.21 118 51.51 5.52 14 .07 .4 .6 SMO 1.4 97 JUL 17 1406 10.51 37 38.20 118 51.69 5.40 23 .07 .3 .5 SMO 2.0 97 JUL 17 1412 2.00 37 38.20 118 51.55 5.47 18 .07 .3 .6 SMO 1.5 97 JUL 17 1412 36.07 37 38.10 118 51.52 1.86 13 .08 .3 .5 SMO 2.1 97 JUL 17 1427 33.28 37 38.46 118 51.15 6.15 7 .02 .5 1.2 SMO 1.0 97 JUL 17 1440 55.81 37 37.85 118 52.09 2.91 31 .26 .5 1.2 SMO 2.3 97 JUL 17 1442 4.18 37 38.23 118 51.48 5.59 19 .06 .3 .5 SMO 1.7 97 JUL 17 1456 10.03 37 38.48 118 51.23 6.37 12 .02 .4 .7 SMO 1.5 97 JUL 17 1501 33.45 37 38.06 118 51.67 5.57 18 .06 .3 .5 SMO 1.6 97 JUL 17 1514 55.19 37 30.88 118 51.25 5.67 7 .05 1.5 2.1 MOR 1.0 97 JUL 17 1555 56.60 37 38.13 118 51.78 5.38 26 .09 .3 .4 SMO 2.3 97 JUL 17 1628 4.97 38 46.49 122 44.93 2.22 9 .03 .4 .6 GEY 1.4 97 JUL 17 1643 53.65 37 38.15 118 51.56 5.61 17 .07 .3 .5 SMO 1.6 97 JUL 17 1803 46.61 37 35.19 118 46.94 0.00 9 .47 2.2 1.6 MOR # 1.0 97 JUL 17 1826 50.78 37 38.32 118 51.57 5.17 14 .07 .4 .6 SMO 1.5 97 JUL 17 1946 37.24 36 57.88 121 35.82 7.41 89 .15 .2 .5 SAR 3.9 97 JUL 17 1952 50.03 36 58.08 121 35.98 5.68 12 .07 .3 .5 SAR 1.4 97 JUL 17 2007 17.45 36 57.84 121 35.62 5.63 9 .06 .4 .6 SAR 1.1 97 JUL 17 2016 0.70 38 48.54 122 48.88 3.76 8 .02 .4 .6 GEY 1.3 97 JUL 17 2035 48.72 37 39.54 118 55.80 7.73 17 .05 .4 .7 SMO 1.4 97 JUL 17 2142 48.02 36 58.24 121 35.92 5.85 17 .13 .3 .7 SAR 1.3 97 JUL 17 2207 3.75 37 38.59 118 51.41 6.32 7 .02 .5 1.7 SMO 1.4 97 JUL 17 2258 34.52 36 58.08 121 35.64 5.52 20 .11 .3 .6 SAR 1.4 97 JUL 17 2352 25.62 36 39.08 121 6.53 10.06 14 .11 .4 .9 BVL 1.3 97 JUL 18 51 28.84 37 38.09 118 51.89 5.59 33 .08 .3 .4 SMO 3.1 97 JUL 18 137 0.21 37 38.39 118 51.90 4.80 27 .06 .2 .4 SMO 2.7 97 JUL 18 139 15.31 37 38.51 118 51.24 6.00 10 .02 .5 .9 SMO 1.4 97 JUL 18 146 11.57 37 38.27 118 51.61 5.16 19 .07 .3 .5 SMO 1.6 97 JUL 18 231 58.77 37 38.48 118 51.31 6.08 12 .02 .4 .8 SMO 1.2 97 JUL 18 402 26.51 37 38.25 118 51.53 4.97 15 .07 .4 .6 SMO 1.4 97 JUL 18 649 55.64 37 34.27 118 50.40 7.23 11 .03 .5 .8 MOR 1.1 97 JUL 18 708 8.44 37 25.28 118 36.30 5.35 7 .1412.110.6 RVL - 1.2 97 JUL 18 811 24.85 37 38.16 118 51.22 5.46 12 .07 .4 .6 SMO 1.4 97 JUL 18 1027 34.51 37 38.30 118 51.81 4.75 14 .06 .4 .6 SMO 1.3 97 JUL 18 1046 22.01 37 38.27 118 54.08 8.43 7 .11 1.4 2.1 SMO 1.3 97 JUL 18 1142 30.35 38 48.79 122 48.45 0.16 10 .07 .3 1.4 GEY # 1.5 97 JUL 18 1150 46.81 37 38.28 118 51.87 5.08 25 .07 .3 .4 SMO 1.9 97 JUL 18 1153 35.28 37 35.29 118 48.13 22.82 7 .09 1.8 8.3 MOR - 1.2 97 JUL 18 1154 24.49 37 38.46 118 51.34 6.25 11 .03 .5 .8 SMO 1.3 --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 97 JUL 18 1324 29.46 40 2.01 123 45.04 14.54 7 .10 2.0 1.2 MAA 1.8 97 JUL 18 1325 39.67 37 38.25 118 51.64 5.10 18 .06 .3 .5 SMO 1.5 97 JUL 18 1539 58.84 38 49.11 122 48.62 4.19 10 .02 .3 .6 GEY 1.5 97 JUL 18 1740 14.75 38 46.95 122 45.75 1.97 7 .07 .4 1.1 GEY 1.1 97 JUL 18 1922 36.22 38 49.36 122 47.57 3.90 8 .02 .3 .8 GEY 1.4 97 JUL 18 1958 27.55 37 38.25 118 51.70 5.51 14 .06 .4 .6 SMO 1.3 97 JUL 18 2026 58.52 36 57.81 121 35.40 6.27 9 .06 .5 .6 SAR 1.0 97 JUL 18 2103 22.20 38 47.89 122 46.96 1.03 8 .02 .3 .5 GEY 1.5 97 JUL 19 30 47.88 38 49.25 122 47.63 4.04 8 .02 .3 .8 GEY 1.3 97 JUL 19 335 41.90 37 33.15 118 44.87 8.92 15 .04 .3 .9 WCN 1.5 97 JUL 19 510 7.16 40 34.13 122 13.83 18.73 18 .22 .6 1.3 SHA 2.4 97 JUL 19 607 17.50 37 38.50 118 51.23 6.31 7 .01 .5 1.1 SMO 1.0 97 JUL 19 609 4.87 37 38.41 118 51.75 4.99 10 .07 .4 .8 SMO 1.0 97 JUL 19 658 6.56 37 38.52 118 51.45 7.25 8 .03 .7 1.5 SMO 1.4 97 JUL 19 658 27.67 37 38.32 118 51.72 5.35 16 .07 .4 .6 SMO 1.7 97 JUL 19 725 32.33 38 49.70 122 48.14 3.52 7 .02 .4 .9 GEY 1.1 97 JUL 19 754 11.64 36 57.96 121 35.71 5.92 15 .07 .3 .5 SAR 1.4 97 JUL 19 1036 56.19 40 24.62 122 6.85 3.32 15 .10 .3 1.7 SHA 2.4 97 JUL 19 1230 52.62 37 38.52 118 51.45 6.32 9 .02 .4 .9 SMO 1.0 97 JUL 19 1359 47.96 38 47.62 122 44.47 2.20 16 .06 .2 .6 GEY 2.0 97 JUL 19 1417 43.61 37 29.21 118 52.07 6.59 18 .05 .5 .5 MOR 1.7 97 JUL 19 1452 10.97 37 38.97 118 54.71 8.06 10 .04 .7 1.3 SMO 1.0 97 JUL 19 1538 4.11 38 56.07 123 4.70 5.54 8 .04 .4 1.8 MAA 1.4 97 JUL 19 1615 52.82 37 38.80 118 54.51 7.91 14 .04 .4 .8 SMO 1.2 97 JUL 19 1620 36.94 37 38.24 118 51.98 5.29 27 .09 .3 .4 SMO 1.7 97 JUL 19 1623 13.21 37 38.50 118 51.51 5.93 16 .04 .3 .6 SMO 1.5 97 JUL 19 1630 9.98 37 38.91 118 54.56 8.28 14 .04 .4 .9 SMO 1.3 97 JUL 19 1708 44.10 40 23.03 122 6.07 0.25 17 .26 .7 9.9 SHA # 2.3 97 JUL 19 1720 32.54 40 22.50 122 5.48 7.88 13 .18 .5 2.8 SHA 2.0 97 JUL 19 1811 33.67 36 57.84 121 35.61 6.46 41 .13 .3 .6 SAR 1.8 97 JUL 19 1825 49.24 37 38.94 118 54.61 8.09 21 .07 .3 .6 SMO 1.8 97 JUL 19 1827 21.23 37 38.78 118 54.83 7.51 9 .04 .6 1.0 SMO 1.0 97 JUL 19 1832 11.24 37 39.12 118 54.39 8.84 14 .03 .5 .7 DOM 1.2 97 JUL 19 1902 37.45 37 39.09 118 54.44 8.66 11 .04 .8 1.3 DOM 1.0 97 JUL 19 1918 18.23 38 50.79 122 47.67 1.60 19 .05 .2 .6 GEY 2.7 97 JUL 19 1954 20.27 37 38.26 118 51.67 5.34 20 .06 .3 .5 SMO 1.6 97 JUL 19 2121 44.35 37 39.32 118 54.33 4.82 17 .08 .3 .6 DOM 1.4 97 JUL 19 2122 7.66 36 49.93 121 25.23 4.70 16 .05 .3 .7 HOL 1.4 97 JUL 19 2156 18.76 38 49.47 122 48.35 3.67 7 .03 .4 .8 GEY 1.3 97 JUL 19 2211 0.50 37 38.84 118 54.68 7.43 12 .04 .4 .9 SMO 1.1 97 JUL 19 2255 3.86 37 39.51 118 55.98 6.23 8 .01 .4 .9 SMO 1.0 97 JUL 19 2333 58.56 37 39.33 118 55.93 6.81 14 .04 .4 .7 SMO 1.1 97 JUL 20 51 46.34 36 57.95 121 35.76 5.89 15 .08 .3 .6 SAR 1.2 97 JUL 20 120 43.76 37 40.85 118 54.14 18.72 12 .27 2.5 7.2 DOM 1.2 --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 97 JUL 20 129 21.87 36 47.21 121 24.51 9.26 21 .11 .3 .8 HOL 1.6 97 JUL 20 214 28.20 38 48.61 122 47.91 3.99 10 .01 .3 .6 GEY 1.7 97 JUL 20 314 46.35 37 32.03 118 50.73 7.62 8 .03 .6 1.4 MOR 1.1 97 JUL 20 429 19.31 37 38.85 118 54.59 7.79 14 .04 .4 .7 SMO 1.4 97 JUL 20 643 3.77 36 39.16 121 14.32 6.47 27 .05 .2 .5 STN 1.8 97 JUL 20 921 49.74 37 34.85 118 51.15 7.84 10 .06 .5 1.2 MOR 1.0 97 JUL 20 944 53.32 37 38.43 118 54.01 6.12 9 .10 .6 1.1 SMO 1.3 97 JUL 20 1121 58.19 40 24.19 122 6.74 2.63 15 .49 1.323.5 SHA # 2.1 97 JUL 20 1149 1.32 36 48.52 121 30.76 3.26 12 .11 .4 .7 SJB 1.4 97 JUL 20 1350 55.70 40 22.15 122 4.61 10.84 10 .07 .5 2.3 SHA 2.0 97 JUL 20 1418 47.20 38 46.54 122 45.14 0.04 7 .07 .3 1.8 GEY # 1.4 97 JUL 20 1438 48.30 37 31.87 118 51.26 9.41 30 .05 .3 .6 MOR 2.3 97 JUL 20 1442 21.54 40 18.92 124 24.90 8.82 7 .05 1.4 .6 MEN 2.6 97 JUL 20 1701 39.88 38 52.32 123 38.87 7.27 31 .11 .9 .7 PAR 2.8 97 JUL 20 2105 8.34 35 55.73 118 44.07 0.18 10 .15 .5 9.0 BAK # 2.2 97 JUL 20 2325 33.91 40 28.27 121 32.71 4.79 11 .03 .3 .6 LAS 2.1 97 JUL 21 230 45.77 37 24.63 121 48.83 1.07 11 .03 .3 1.3 ALU 1.6 97 JUL 21 335 57.70 37 35.71 118 54.26 6.34 18 .05 .4 .6 SIL 1.4 97 JUL 21 525 46.74 36 34.49 121 7.70 11.04 17 .04 .3 .8 BVL 1.4 97 JUL 21 642 6.11 40 34.47 122 14.57 16.70 12 .19 .6 2.0 SHA 2.3 97 JUL 21 1224 20.75 37 38.74 118 52.44 5.65 15 .06 .4 .5 SMO 1.4 97 JUL 21 1452 4.93 37 38.24 118 51.04 5.14 10 .07 .4 .9 SMO 1.0 97 JUL 21 1453 46.88 37 38.14 118 51.36 5.42 18 .07 .3 .5 SMO 1.4 97 JUL 21 1646 57.69 37 20.54 121 43.05 0.38 19 .05 .2 1.5 ALU 1.7 97 JUL 21 1758 0.12 38 47.98 122 47.59 0.46 9 .07 .3 .5 GEY 1.8 97 JUL 21 1815 30.79 38 0.46 122 3.38 12.87 17 .17 .6 .8 CON 1.8 97 JUL 21 1838 56.25 35 52.63 120 25.53 9.77 9 .02 .5 .7 GOL 1.5 97 JUL 21 2005 28.70 37 38.19 118 51.44 5.33 11 .05 .4 .6 SMO 1.3 97 JUL 21 2224 28.99 40 40.72 124 22.92 21.07 27 .08 .6 .5 EUR 3.5 97 JUL 22 14 0.12 40 18.19 124 20.23 6.81 7 .05 1.2 1.2 MEN 2.1 97 JUL 22 127 21.36 37 38.11 118 51.28 5.11 13 .07 .4 .6 SMO 1.1 97 JUL 22 300 58.84 38 47.62 122 48.57 4.21 9 .02 .4 .7 GEY 1.4 97 JUL 22 1806 34.04 37 33.72 118 49.94 3.93 8 .02 .4 1.6 MOR 1.0 97 JUL 22 1814 42.65 37 38.80 118 57.72 7.41 14 .05 .4 .7 SMO 1.0 97 JUL 22 2012 25.01 36 44.53 121 6.16 3.65 12 .47 4.217.5 PAN # 1.3 97 JUL 22 2349 47.84 40 33.94 122 14.63 19.66 9 .10 .5 1.5 SHA 2.3 97 JUL 23 54 41.36 38 47.76 122 44.59 1.75 8 .03 .3 .8 GEY 1.5 97 JUL 23 318 3.82 40 54.17 123 22.30 25.17 44 .19 .4 3.6 KLA 3.9 97 JUL 23 458 35.59 38 49.07 122 47.77 3.63 12 .04 .3 .7 GEY 1.6 97 JUL 23 845 39.31 38 48.09 122 47.35 0.32 9 .02 .2 1.5 GEY 1.7 97 JUL 23 930 7.13 37 37.38 118 41.42 0.94 7 .14 2.611.6 CAS - 1.1 97 JUL 23 930 54.79 37 33.54 118 46.15 16.67 7 .10 2.8 8.4 WCN - 1.0 --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 97 JUL 23 1043 7.98 38 40.46 122 43.43 6.71 14 .07 .4 .8 NAP 1.5 97 JUL 23 1348 4.65 37 32.54 118 51.12 12.09 7 .05 1.3 3.1 MOR 1.1 97 JUL 23 1422 44.70 37 39.91 118 49.95 3.06 22 .07 .3 .6 HCF 1.9 97 JUL 23 1651 11.99 36 35.26 121 11.17 4.96 8 .04 1.0 .6 PIN 1.0 97 JUL 23 1713 8.80 38 36.89 122 41.43 8.74 8 .05 .4 1.4 NAP 1.3 97 JUL 23 1919 39.99 37 34.32 118 50.34 7.33 14 .03 .3 .7 MOR 1.5 97 JUL 23 2203 56.20 40 18.20 124 33.44 19.42 28 .09 1.1 .4 MEN 3.4 97 JUL 23 2240 11.05 37 39.86 118 49.84 3.55 18 .07 .3 .6 HCF 1.6 97 JUL 23 2240 31.89 37 40.93 118 48.43 4.36 9 .03 3.6 1.3 EMO 1.2 97 JUL 24 102 11.24 37 39.90 118 49.61 3.25 10 .06 .4 .9 HCF 1.1 97 JUL 24 134 4.49 37 38.05 118 56.15 7.95 10 .05 .7 1.1 SMO 1.0 97 JUL 24 159 9.39 38 46.09 122 42.55 0.46 7 .06 .6 .8 GEY 1.2 97 JUL 24 221 2.85 37 30.47 121 40.33 8.46 8 .01 .4 1.8 HAM 1.1 97 JUL 24 307 9.61 37 39.69 118 53.76 5.97 9 .07 .6 1.0 DOM 1.4 97 JUL 24 307 41.76 37 38.43 118 54.47 8.21 14 .05 .4 .9 SMO 2.1 97 JUL 24 307 50.12 37 38.09 118 54.50 8.25 8 .03 .9 1.1 SMO 1.2 97 JUL 24 308 22.41 37 38.74 118 54.70 9.57 8 .04 .7 1.5 SMO 1.0 97 JUL 24 312 16.14 37 38.21 118 54.59 8.05 15 .04 .4 .6 SMO 1.3 97 JUL 24 327 43.43 37 38.14 118 54.89 6.73 15 .13 .5 .6 SMO 1.0 97 JUL 24 509 17.76 36 28.07 121 2.60 5.60 21 .05 .3 .6 BIT 1.8 97 JUL 24 641 17.18 38 49.03 122 50.08 1.09 12 .04 .2 .6 GEY 1.6 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 ------------------------------------------------------------------------------- JUL 15 035358.4* 23.156S 63.423W 33N 4.7 1.1 39 SALTA PROVINCE, ARGENTINA 043925.2 36.882N 95.296E 33N 4.7 4.0 0.6 43 QINGHAI, CHINA 143409.1 34.037N 117.236W 5G 1.1 27 SOUTHERN CALIFORNIA. ML 2.9 203540.6% 43.237N 0.365W 5G 0.9 18 PYRENEES. ML 3.3 (LDG). 210041.2 38.287N 26.771W 10G 4.5 4.0 0.9 49 AZORES ISLANDS JUL 16 020959.8* 21.754S 177.190W 183D 4.5 0.7 25 FIJI ISLANDS REGION 071531.4 59.968N 151.508W 33N 1.1 97 KENAI PENINSULA, ALASKA. ML 3.9 073224.3 8.150S 74.362W 159D 4.6 0.9 75 PERU-BRAZIL BORDER REGION 100607.2 39.104N 25.190E 10G 4.8 3.9 1.2 63 AEGEAN SEA. Felt at Burhaniye, Turkey. 104327.2* 28.489N 43.664W 10G 4.6 4.3 0.9 24 NORTHERN MID-ATLANTIC RIDGE 104608.2? 28.64 N 42.63 W 10G 4.2 0.8 7 NORTHERN MID-ATLANTIC RIDGE 104727.6 28.637N 43.779W 10G 4.7 4.7 1.2 42 NORTHERN MID-ATLANTIC RIDGE 105308.8* 28.514N 43.445W 10G 5.0 5.1 0.9 34 NORTHERN MID-ATLANTIC RIDGE 163146.5* 22.999S 68.213W 100G 4.3 1.4 28 NORTHERN CHILE 213844.6& 45.018N 121.881W 4 10 WASHINGTON-OREGON BORDER. MD 2.6 JUL 17 062953.6 62.675N 152.340W 33N 1.2 21 CENTRAL ALASKA. ML 3.7 070133.1? 22.94 S 175.64 W 33N 4.9 4.7 0.9 28 TONGA ISLANDS REGION 070309.6? 23.20 S 175.13 W 33N 4.8 1.5 17 TONGA ISLANDS REGION 071742.1 63.306N 151.183W 33N 1.1 25 CENTRAL ALASKA. ML 4.0 084508.9* 7.761S 108.027E 33N 4.7 1.2 30 JAWA, INDONESIA 085445.7% 34.046S 71.016W 33N 0.6 10 NEAR COAST-CENTRAL CHILE. MD 3.0 124535.0 3.663N 74.119W 33N 4.9 4.0 0.9 75 COLOMBIA. Felt at Bogota and Villavicencio. Also felt in Caqueta Department. 141948.3 51.960N 178.947E 100G 4.3 1.1 33 RAT ISLANDS, ALEUTIAN ISLANDS. ML 4.2 (PMR). 154208.4 18.190N 145.515E 221D 4.7 1.1 72 MARIANA ISLANDS 194637.0& 36.960N 121.600W 7 23 CENTRAL CALIFORNIA. Mw 3.9, ML 4.1 Felt at San Francisco, San Jose, and Santa Cruz. JUL 18 005129.2 37.671N 118.846W 5G 0.8 12 CALIFORNIA-NEVADA BORDER. ML 3.4 144551.4* 60.477S 25.006W 33N 4.7 1.0 13 SOUTH SANDWICH ISLANDS REGION 185941.9? 29.64 N 68.46 E 33N 5.1 0.9 7 PAKISTAN 193921.9? 26.73 N 91.72 E 33N 4.9 0.5 16 NORTHEASTERN INDIA 235042.4* 45.864N 149.934E 33N 5.1 0.6 55 KURIL ISLANDS JUL 19 073437.9* 17.651N 100.149W 33N 4.7 3.8 1.0 43 GUERRERO, MEXICO. Felt. 122257.8 29.043S 71.397W 26D 5.8 5.4 0.7 97 NEAR COAST-CENTRAL CHILE. Felt (V) at Vallenar; (IV) at Caldera, Chanaral, Copiapo, El Salvador and Ovalle; (III) at Coquimbo and La Serena. 142204.8 15.843N 98.193W 33N 5.7 6.2 1.0 96 OFF COAST OF GUERRERO, MEXICO. Mw 6.8. Felt in Guerrero and Oaxaca. Also felt at Mexico City. 145452.6? 16.33 N 98.06 W 33N 4.1 1.0 10 NEAR COAST OF GUERRERO, MEXICO 150440.9? 16.50 N 98.24 W 33N 3.5 1.2 9 NEAR COAST OF GUERRERO, MEXICO 161015.5* 22.797S 169.318E 33N 5.8 5.4 0.7 55 LOYALTY ISLANDS REGION 170124.9? 33.88 N 141.66 E 33N 4.6 0.6 24 OFF EAST COAST OF HONSHU, JAPAN 170636.4 35.015N 84.615W 10G 0.6 10 TENNESSEE. mbLg 3.5 (GS). 174057.7* 16.513N 98.067W 33N 4.6 4.1 1.1 40 NEAR COAST OF GUERRERO, MEXICO 182728.9? 16.53 N 98.13 W 33N 3.9 0.8 9 NEAR COAST OF GUERRERO, MEXICO 192932.6? 16.46 N 98.10 W 33N 4.1 0.7 11 NEAR COAST OF GUERRERO, MEXICO 224000.2? 16.79 N 98.23 W 33N 4.1 1.4 10 NEAR COAST OF GUERRERO, MEXICO JUL 20 003020.7 52.677N 167.536W 15D 5.6 5.9 1.1 123 FOX ISLANDS, ALEUTIAN ISLANDS. Mw 6.2 (GS). 003839.5* 52.661N 167.492W 33N 4.4 1.0 9 FOX ISLANDS, ALEUTIAN ISLANDS 005529.2 52.639N 167.399W 33N 4.8 0.9 35 FOX ISLANDS, ALEUTIAN ISLANDS 033908.6* 41.262N 20.013E 10G 4.6 1.0 10 ALBANIA 034030.5? 16.83 N 98.22 W 33N 4.2 0.8 18 NEAR COAST OF GUERRERO, MEXICO 063509.8? 16.64 N 98.10 W 33N 4.2 0.8 20 NEAR COAST OF GUERRERO, MEXICO 092430.0* 41.246N 19.967E 10G 3.8 1.1 16 ALBANIA 101423.5 22.667S 66.024W 257D 6.0 0.7 110 JUJUY PROVINCE, ARGENTINA. Mw 6.1 Felt (IV) at Calama and Mejillones; (III) at Antofagasta, San Pedro de Atacama and Tocopilla, Chile. 104944.0* 6.071S 145.516E 121D 5.1 0.9 15 NEW GUINEA, PAPUA NEW GUINEA 114943.1* 3.304N 128.378E 33N 4.9 1.1 11 NORTH OF HALMAHERA, INDONESIA 115230.0? 16.27 N 98.11 W 33N 4.2 1.1 26 NEAR COAST OF GUERRERO, MEXICO 174348.8 18.972N 46.103W 10G 4.8 4.5 0.7 34 NORTHERN MID-ATLANTIC RIDGE 193310.7* 16.784S 179.204W 490D 4.5 0.6 41 FIJI ISLANDS REGION JUL 21 074640.2* 8.819S 108.105W 10G 5.0 4.7 0.8 47 CENTRAL EAST PACIFIC RISE 083256.6* 8.748S 108.083W 10G 4.8 4.3 0.8 52 CENTRAL EAST PACIFIC RISE 145621.9* 8.785S 108.091W 10G 4.8 4.2 0.7 36 CENTRAL EAST PACIFIC RISE 175416.4 30.101S 71.715W 33N 4.8 4.8 0.8 35 NEAR COAST-CENTRAL CHILE. Felt (II) at Coquimbo and La Serena. 231940.2* 30.078S 71.738W 33N 5.2 5.5 1.0 59 NEAR COAST-CENTRAL CHILE. Mw 6.1 Felt (III) at La Serena. JUL 22 000956.7 47.774N 122.364W 15G 0.6 6 WASHINGTON. ML 2.8 (GS). 020934.8* 29.687S 71.618W 33N 4.9 4.7 0.9 50 NEAR COAST-CENTRAL CHILE. Felt (III) at Coquimbo, La Serena, Ovalle and Santiago. 083320.4* 20.388S 178.700W 529D 4.9 0.5 77 FIJI ISLANDS REGION 101655.0 6.191S 154.734E 51D 5.6 0.6 73 SOLOMON ISLANDS. Mw 5.6 112140.5 36.318N 120.450W 5G 0.8 11 CENTRAL CALIFORNIA. ML 2.8 (GS). 134456.2* 31.915S 71.409W 33N 4.7 4.1 0.8 19 NEAR COAST-CENTRAL CHILE. /Felt (IV) at Catemu, Illapel, Llaillay, Los Vilos, Panquehue and Salamanca; (III) at La Ligua, Papudo, Quillota, San Felipe, Santa Maria, and Santiago; and (II) at Coquimbo, La Serena and Ovalle. 142815.4? 22.89 S 175.08 W 33N 4.8 4.9 0.6 24 TONGA ISLANDS REGION 162140.3* 66.169N 18.174W 10G 4.8 4.6 1.0 32 ICELAND REGION 174342.3* 16.193N 98.202W 33N 4.8 4.1 1.1 44 NEAR COAST OF GUERRERO, MEXICO 180124.0? 16.62 N 98.04 W 33N 4.3 1.0 20 NEAR COAST OF GUERRERO, MEXICO 191034.6 4.566N 32.619W 10G 5.5 5.1 0.9 72 CENTRAL MID-ATLANTIC RIDGE. 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.