EARTHQUAKES IN ALASKA October 2007 ALASKA EARTHQUAKE INFORMATION CENTER

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1 EARTHQUAKES IN ALASKA October 2007 ALASKA EARTHQUAKE INFORMATION CENTER A report of the Alaska State Seismologist s Office

2 Alaska Earthquake Information Center Geophysical Institute, University of Alaska 903 Koyukuk Drive, P.O. Box Fairbanks, AK TEL: (907) ; FAX: (907) EARTHQUAKES IN ALASKA - October 2007 By N. Ruppert with the assistance of N. Kozyreva and J. Roush Issued: January, 2008 The Alaska Earthquake Information Center is a cooperative program between the Geophysical Institute of the University of Alaska and the U.S. Geological Survey with the support from the Earthquake Hazards Program. DISCLAIMER This report has not been edited or reviewed for conformity with U. S. Geological Survey and State of Alaska standards and nomenclature. The data in this report are preliminary and subject to revision. Most of the earthquake parameters have been determined by AEIC. The data are released on the condition that neither the U.S. Geological Survey, nor the United States Government, nor the Geophysical Institute, University of Alaska Fairbanks may be held liable for any damages resulting from its authorized or unauthorized use. Alaska State Seismologist s Report

3 The Alaska Earthquake Information Center (AEIC) is a cooperative program established to monitor earthquakes in Alaska and to provide earthquake information to citizens and public officials and to the earth science community. Most of the earthquakes located by AEIC occur in a core area in central and southern Alaska, between latitudes 57 o N and 67 o N, and longitudes 135 o W and 156 o W; however, this listing also includes earthquakes not located by AEIC but reported in the National Earthquake Information Center s (NEIC) monthly Preliminary Determination of Epicenters (PDE) for a larger region between latitudes 48 o N and 75 o N, and longitudes 130 o W to 170 o E. The magnitude level for completeness and the precision of the locations vary across the state due to uneven station spacing and to differences in earthquake depths. The data are more complete and the hypocenters are more accurate in regions where the station density is greatest. In southern and central Alaska where the majority of the stations are located, the earthquake catalogs are complete for shallow (depth < 30 km) earthquakes of about magnitude 1.5 and larger. The magnitude threshold at which the catalogs are complete increases with depth. For earthquakes deeper than 100 km in southern and central Alaska, the catalogs are complete above about magnitude 2.0. The earthquake catalogs are reasonably complete for the entire state for events greater than or equal to magnitude 3.0. Earthquakes in southern and central Alaska, where calculated hypocenters are more accurate, have horizontal (epicentral) and vertical (depth) errors (median value) of 1.1 and 1.9 km, respectively. Neogene and younger faults plotted on the seismicity figures are modified from: Plafker, G., Gilpin, L., and Lahr, J.C., 1994, Neotectonic map of Alaska, in Plafker, G., and Berg, H.C., eds., The geology of Alaska: Boulder, Colorado, Geological Society of America, The Geology of North America, v. G-1, plate 12, scale 1:2,500,000. The seismicity shown for western Canada is not complete, and does not represent the total activity for the area. For more information on Canadian seismicity, contact: Pacific Geoscience Center, Geological Survey of Canada, P.O. Box 6000 Sidney, British Columbia, V8L 4B2 Canada. Cover Seismic monitoring site ISLE in the Wrangell-St.Elias mountains region, southern Alaska. Photo by S. Estes, AEIC, Geophysical Institute, UAF. Acknowledgments Supplemental data provided by the United States Geological Survey, National Earthquake Information Center, Golden, Colorado; the Geological Survey of Canada, Pacific Geoscience Centre, Sidney, British Columbia; the Alaska Volcano Observatory, Anchorage, Alaska; and the National Oceanic and Atmospheric Administration, National Weather Service, Alaska Tsunami Warning Center, Palmer, Alaska.

4 CONTENTS This monthly earthquake catalog contains the following: Highlights: Summary plot: Maps and cross-sections: Listings: A discussion of important or particularly interesting earthquakes which occurred during the month. A plot with the earthquake statistics: time-magnitude plot, number of located events per day, cumulative number of located events, depth histogram, frequency-magnitude relationship for the Aleutian and mainland Alaska events. Five maps illustrating Alaska seismicity during the month. Figure 1 is a map which includes all located earthquakes for the state and surrounding region. Figure 2a focuses on earthquakes in a core area of central and southern Alaska, and depicts line segments for two cross-sections through the Alaska/ Aleutian Wadati Benioff zone (Figure 2b). Figure 3 shows events in the core area larger than magnitude 3.0, Figure 4 shows all core events shallower than 30 km depth, and Figure 5 shows all core events of depth greater than or equal to 30 km. Three listings of hypocenters are presented, as follows: first, a complete listing of all located earthquakes for the month, corresponding to the epicenters plotted in Figure 1; next, Appendix 1 contains a subset of the full listing restricted to only those events of magnitude 4.0 and larger; and lastly, Appendix 2 lists known or suspected quarry blasts during the month. These blasts have been excluded from Figures 1-5. Listings include, for each event: date and origin time, epicenter, depth, preferred magnitude, solution quality statistics and comments (region, alternate magnitudes, available felt reports and other remarks). Other types of information available regularly from AEIC: Parameters for the most recent 100 earthquakes of magnitude 2.0 and larger are available through the Internet ( OR by sending to quake@giseis.alaska.edu; in the latter case a return message will contain the earthquake listing. Weekly and Monthly Seismicity Reports - issued within seven days of the end of each week and month, respectively. These reports include highlights of recent activity, a preliminary listing of events, and epicenter maps. The weekly and monthly reports may be found on the Internet at Catalog of Alaska Earthquake Focal Mechanisms - annual catalogs of focal mechanisms determined from initial P-wave polarities recorded by the regional seismograph network, as well as source mechanisms determined independently by NEIC and other seismic observatories. 1

5 HIGHLIGHTS During October, 2007, the Alaska Earthquake Information Center located 2,093 events, thirty seven of which had magnitudes equal to or greater than 4.0 and twenty three of which were suspected quarry blasts. The largest event (M6.3) occurred on October 2 in the Alaska Peninsula region of Alaska. Ten events were felt. Earthquakes of particular interest during the month are discussed below: October 2, 18:00:07 UTC (10:00 am ADT), M W 6.3, M L 6.0, mb 6.2, M S 6.2, o N o W, depth=28.9 km: A strong earthquake occurred in the Alaska Peninsula region and was located 71 km (45 miles) SSE of King Cove and 99 km (62 miles) SE of Cold Bay. It was felt in Cold Bay, King Cove and Sand Point, with maximum intensity of shaking VI, strong. The AEIC located over 400 aftershocks with magnitudes 2.0 and greater through the end of the month. Fifteen aftershocks had magnitudes 4.0 or greater of which four had magnitudes greater than 5. The largest aftershock of magnitude 5.6 occurred three minutes after the mainshock. This earthquake is the largest to occur in the region since the M6.2 event on November 20, The October 2, 2007 earthquake occurred on the convergent boundary between the subducting Pacific and the overriding North American crustal plates. The current sequence of earthquakes is located within the so-called Shumagin seismic gap. According to the crust deformation measurements, no significant strain is being accumulated within the gap. October 3, 14:06:12 UTC (6:06 am ADT), M L 5.0, M W 5.2, m b 5.0, M S 4.4, o N o W, depth=45.5 km: A moderate earthquake occurred in the Kodiak Island region and was located 86 km (54 miles) NE of Kodiak and 153 km (96 miles) S of Homer. It was felt in Kodiak and Homer, maximum intensity IV, light. The waveform radiation pattern indicates strike-slip faulting. The depth and focal mechanism of the event indicate that it occurred inside the subducting Pacific plate 2

6 SUMMARY PLOT A summary plot of events with magnitudes. The lower left panel shows number of the located events per day, their magnitudes, and the cumulative number. The upper left panel is the depth histogram. The right panel shows the frequency-magnitude distribution of the Aleutian Islands (upper figure) and the mainland Alaska (lower figure) earthquakes with estimates of the b-value and magnitude of completeness. 2007/10/1 2007/10/31: 2091 earthquakes Aleutian Islands, b (M>2.5)= / # of events Depth in [km] Cumulative Number Cumulative # Magnitude Mainland Alaska, b (M > 1.4) = / # per day Magnitude day Cumulative Number Magnitude 3

7 4

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13 Monthly Listing of Earthquake Hypocenters in Alaska Events are listed in chronological order. The following data are given for each event: 1. DATE AND TIME in Coordinated Universal Time (UTC): year (YR), month (MO), day (DY), hour (HR), minute (MN) and second (SEC). To convert to Alaska Standard Time (AST) or Alaska Daylight Time (ADT) subtract 9 or 8 hours, respectively. 2. LATITUDE and LONGITUDE of epicenter in degrees (DEG) and minutes (MIN). 3. DEPTH, depth of focus in kilometers. Symbols after the depth indicate the following: N = Depth was fixed at 33 km for earthquakes whose character on seismograms indicates a shallow focus but whose depth is not satisfactorily determined by the data. D = Depth was restrained by the computer program based on 2 or more compatible pp phases and/or unidentified secondary arrivals used as pp. G = Depth was fixed at other than 33 km. * or? = Less well-constrained free depth determined by NEIC. For detailed explanation see January 1993 Preliminary Determation of Epicenters. 4. PREF MAG, the AEIC ML is the preferred magnitude, unless it is unavailable or when the National Earthquake Information Center (NEIC) m b > 4.5 or M S > 6.8. For preferred magnitudes other than AEIC ML a letter code after the magnitude indicates the type as follows: mb = Body-wave magnitude (Mb) computed by NEIS. Ms = Surface wave magnitude (MS) computed by NEIS. A = Local magnitude (ML) from Alaska Tsunami Warning Center, Palmer, Alaska (PMR). C = Local magnitude (ML) from Pacific Geoscience Centre, Sidney, British Columbia, Canada (PGC). D = Duration magnitude (MD) from AEIC. L = Duration magnitude (MD) from Columbia University, Lamont-Doherty Earth Observatory, Palisades, New York (PAL). 5. RMS, root-mean-square traveltime residual in seconds: RMS = W i R i 2 Where R i is the observed minus computed time of the i-th observation. W i is the corresponding weight of the observation, and weights are normalized so that their sum equals N, the total number of P, S, and S-P observations used in the solution. 6. SEH, standard error in the horizontal direction with least control in kilometers. 7. SEZ, standard error of depth in kilometers. 8. GAP, largest azimuthal separation between stations in degrees with respect to the epicenter. 9. PHASES, number of P and S phases used in the solution. 10. MIN DIS, epicentral distance in kilometers to the station closest to the epicenter. 11. Q, quality of the hypocenter. This index is a measure of the precision of the hypocenter and is calculated from SEH and SEZ: Q Larger of SEH and SEZ (km) A < 1.34 B < 2.67 C < 5.35 D > T, event type as follows: E - Local or regional tectonic earthquake located by AEIC. a - Volcano-tectonic earthquake located by AEIC. B - Long period volcano earthquake located by AEIC. R - Regional event not located by AEIC. Q - Known or suspected quarry or mine blast located by AEIC. 13. COMMENTS, symbols and abbreviations used in comments: BRK - University of California, Berkeley. Mo - Seismic moment. NEIS - U.S. Geological Survey, National Earthquake Information Service. PAL - Columbia University, Lamont-Doherty Earth Observatory, Palisades, New York. PAS - California Institute of Technology, Pasadena. PGC - Pacific Geoscience Centre, Sidney, British Columbia, Canada. PMR - Alaska Tsunami Warning Center, Palmer, Alaska. PPT - Laboratoire de Geophysique, Papeete, French Polynesia. SPEC - An NEIS solution based on use of dense local networks, a local crustal model, or other methods not routinely applied in calculating the hypocenter parameters. Errors and uncertainties in the reported parameters may result from random errors present in the phase data, or from systematic errors introduced either by the velocity models used to locate the earthquakes or by poor geometrical distribution of recording stations about the source. One should be particularly cautious using solutions that have GAP > 180 degrees, PHASES < 6, MIN DIS > DEPTH, RMS > 1s, SEH > 5km, or SEZ > 10km. Solutions with A and B quality are generally more reliable, but this does not guarantee that the accuracy of the solutions is within the limits implied by SEH and SEZ. Catalogs prior to January 1998 have printed SEH and SEZ values that are too large by a factor of N i N 10

14 AEIC Monthly Earthquake Listing DATE LAT LON DEPTH MAG RMS SEH SEZ GAP PHASES MIN Q T REGION yy mo dy jday hh:mn:sec DEG DEG km mb ML sec. km km deg P,S DIS (274) 00:03: A E CENTRAL ALASKA (274) 01:25: A E CENTRAL ALASKA (274) 02:20: A E CENTRAL ALASKA (274) 02:50: A E CENTRAL ALASKA (274) 03:27: A E CENTRAL ALASKA (274) 03:31: A E SOUTHERN ALASKA (274) 04:26: A E CENTRAL ALASKA (274) 04:55: A E SOUTHERN ALASKA (274) 05:08: G B G SOUTHEASTERN ALASKA (274) 05:22: A E SOUTHERN ALASKA (274) 05:36: A E CENTRAL ALASKA (274) 05:58: A E SOUTHERN ALASKA (274) 06:04: A E CENTRAL ALASKA (274) 06:22: C E ALASKA (274) 06:59: A E CENTRAL ALASKA (274) 07:28: D E GULF OF ALASKA (274) 08:04: A E SOUTHERN ALASKA (274) 08:16: A E SOUTHERN ALASKA (274) 09:31: A E CENTRAL ALASKA (274) 10:06: A E CENTRAL ALASKA (274) 10:40: A E CENTRAL ALASKA (274) 11:22: A E CENTRAL ALASKA (274) 11:31: G A E CENTRAL ALASKA (274) 11:50: A E CENTRAL ALASKA (274) 12:24: G A E CENTRAL ALASKA (274) 12:43: A E CENTRAL ALASKA (274) 13:55: A E CENTRAL ALASKA (274) 14:19: A E SOUTHERN ALASKA (274) 14:32: A E CENTRAL ALASKA (274) 14:58: G A E CENTRAL ALASKA (274) 16:06: A E CENTRAL ALASKA (274) 16:19: A E CENTRAL ALASKA (274) 16:20: A E CENTRAL ALASKA (274) 16:50: A E CENTRAL ALASKA (274) 17:41: D E FOX ISLANDS, ALEUTIAN IS (274) 17:47: A E ALASKA PENINSULA (274) 17:55: A E CENTRAL ALASKA (274) 19:03: A E CENTRAL ALASKA (274) 19:26: A E CENTRAL ALASKA (274) 19:50: A E KODIAK ISLAND REGION (274) 19:51: A E KODIAK ISLAND REGION (274) 19:54: A E CENTRAL ALASKA (274) 20:28: A E CENTRAL ALASKA (274) 21:18: A E SOUTHERN ALASKA (274) 21:59: A E CENTRAL ALASKA (274) 22:10: G A E CENTRAL ALASKA (274) 22:11: G A E CENTRAL ALASKA (274) 22:28: D E NORTHERN YUKON TERR., CAN (274) 23:14: G A Q CENTRAL ALASKA (275) 00:59: A E FOX ISLANDS, ALEUTIAN IS (275) 01:04: A E ANDREANOF IS., ALEUTIAN IS (275) 01:33: A E KODIAK ISLAND REGION (275) 01:34: D E ALASKA (275) 01:43: A E CENTRAL ALASKA (275) 02:01: G C G SOUTHEASTERN ALASKA (275) 02:13: A E ANDREANOF IS., ALEUTIAN IS (275) 03:44: A E CENTRAL ALASKA (275) 04:13: D E RAT ISLANDS, ALEUTIAN IS (275) 04:39: A E CENTRAL ALASKA (275) 06:14: C E ANDREANOF IS., ALEUTIAN IS. 11

15 (275) 06:43: A E CENTRAL ALASKA (275) 07:09: B E RAT ISLANDS, ALEUTIAN IS (275) 07:41: A E SOUTHERN ALASKA (275) 09:22: A E CENTRAL ALASKA (275) 09:23: A E ANDREANOF IS., ALEUTIAN IS (275) 09:41: A E KENAI PENINSULA, ALASKA (275) 09:48: A E ANDREANOF IS., ALEUTIAN IS (275) 11:42: A E KENAI PENINSULA, ALASKA (275) 11:53: A E CENTRAL ALASKA (275) 12:35: B E CENTRAL ALASKA (275) 12:41: A E CENTRAL ALASKA (275) 13:21: G A E CENTRAL ALASKA (275) 13:48: G A G SOUTHEASTERN ALASKA (275) 14:00: A E ALASKA PENINSULA (275) 14:16: A E KENAI PENINSULA, ALASKA (275) 14:35: A E CENTRAL ALASKA (275) 15:56: A E CENTRAL ALASKA (275) 16:14: D E ALASKA PENINSULA (275) 16:46: G A G SOUTHEASTERN ALASKA (275) 17:00: A E SOUTHERN ALASKA (275) 17:22: G A G SOUTHEASTERN ALASKA (275) 18:00: B F ALASKA PENINSULA Felt in King Cove, Cold Bay, and Sand Point. Maximum intensity VI (275) 18:02: D E ALASKA PENINSULA (275) 18:03: C E ALASKA PENINSULA (275) 18:05: D E ALASKA PENINSULA (275) 18:06: D E ALASKA PENINSULA (275) 18:08: D E ALASKA PENINSULA (275) 18:09: D E ALASKA PENINSULA (275) 18:11: D E ALASKA PENINSULA (275) 18:13: D E ALASKA PENINSULA (275) 18:17: B E ALASKA PENINSULA (275) 18:19: C E ALASKA PENINSULA (275) 18:21: D E ALASKA PENINSULA (275) 18:22: B E ALASKA PENINSULA (275) 18:25: D E ALASKA PENINSULA (275) 18:26: D E ALASKA PENINSULA (275) 18:27: C E ALASKA PENINSULA (275) 18:28: D E ALASKA PENINSULA (275) 18:29: C E ALASKA PENINSULA (275) 18:32: D E ALASKA PENINSULA (275) 18:34: D E ALASKA PENINSULA (275) 18:34: C E ALASKA PENINSULA (275) 18:39: D E ALASKA PENINSULA (275) 18:41: C E ALASKA PENINSULA (275) 18:42: C E ANDREANOF IS., ALEUTIAN IS (275) 18:47: D E ALASKA PENINSULA (275) 18:48: D E ALASKA PENINSULA (275) 18:49: D E ALASKA PENINSULA (275) 18:51: B E ALASKA PENINSULA (275) 18:54: C E ALASKA PENINSULA (275) 18:57: D E ALASKA PENINSULA (275) 18:58: D E ALASKA PENINSULA (275) 19:00: B E ALASKA PENINSULA (275) 19:03: C E ALASKA PENINSULA (275) 19:09: C E ALASKA PENINSULA (275) 19:16: D E ALASKA PENINSULA (275) 19:16: D E ALASKA PENINSULA (275) 19:20: D E ALASKA PENINSULA (275) 19:24: B E ALASKA PENINSULA (275) 19:27: B E ALASKA PENINSULA (275) 19:41: D E ALASKA PENINSULA (275) 19:45: D E ALASKA PENINSULA (275) 19:47: B E FOX ISLANDS, ALEUTIAN IS (275) 19:51: D E FOX ISLANDS, ALEUTIAN IS (275) 19:57: D E ALASKA PENINSULA (275) 19:59: D E ALASKA PENINSULA (275) 20:06: D E ALASKA PENINSULA 12

16 (275) 20:07: D E ALASKA PENINSULA (275) 20:12: A E KODIAK ISLAND REGION (275) 20:22: B E ALASKA PENINSULA (275) 20:31: B E CENTRAL ALASKA (275) 20:31: B E ALASKA PENINSULA (275) 20:35: D E ALASKA PENINSULA (275) 20:39: A E SOUTHERN ALASKA (275) 20:39: D E ALASKA PENINSULA (275) 20:44: D E ALASKA PENINSULA (275) 20:45: A E ANDREANOF IS., ALEUTIAN IS (275) 20:47: D E ALASKA PENINSULA (275) 20:49: D E ALASKA PENINSULA (275) 20:53: D E ALASKA PENINSULA (275) 20:53: A E ANDREANOF IS., ALEUTIAN IS (275) 20:54: D E ALASKA PENINSULA (275) 20:57: B E ALASKA PENINSULA (275) 20:57: D E ALASKA PENINSULA (275) 21:00: D E ALASKA PENINSULA (275) 21:01: D E ALASKA PENINSULA (275) 21:02: D E ALASKA PENINSULA (275) 21:05: B E ALASKA PENINSULA (275) 21:08: C E ALASKA PENINSULA (275) 21:09: A E CENTRAL ALASKA (275) 21:10: C E ALASKA PENINSULA (275) 21:12: D E ALASKA PENINSULA (275) 21:16: D E ALASKA PENINSULA (275) 21:18: G D E ALASKA PENINSULA (275) 21:19: D E ALASKA PENINSULA (275) 21:24: D E ALASKA PENINSULA (275) 21:25: A E CENTRAL ALASKA (275) 21:28: D E ALASKA PENINSULA (275) 21:31: D E ALASKA PENINSULA (275) 21:32: A E ALASKA PENINSULA (275) 21:33: D E ALASKA PENINSULA (275) 21:35: D E ALASKA PENINSULA (275) 21:38: B E ALASKA PENINSULA (275) 21:40: D E ALASKA PENINSULA (275) 21:47: C E ALASKA PENINSULA (275) 21:58: G A G SOUTHEASTERN ALASKA (275) 21:59: B E ALASKA PENINSULA (275) 22:01: D E ALASKA PENINSULA (275) 22:01: D E ALASKA PENINSULA (275) 22:05: D E ALASKA PENINSULA (275) 22:08: D E ALASKA PENINSULA (275) 22:11: D E ALASKA PENINSULA (275) 22:18: D E ALASKA PENINSULA (275) 22:20: A E CENTRAL ALASKA (275) 22:21: C E ALASKA PENINSULA (275) 22:24: D E ALASKA PENINSULA (275) 22:25: D E ALASKA PENINSULA (275) 22:43: A E SOUTHERN ALASKA (275) 22:44: B E ALASKA PENINSULA (275) 22:50: G D E ALASKA PENINSULA (275) 22:59: B E ALASKA PENINSULA (275) 23:03: G A Q CENTRAL ALASKA (275) 23:04: D E ALASKA PENINSULA (275) 23:09: D E ALASKA PENINSULA (275) 23:15: D E ALASKA PENINSULA (275) 23:25: A E ALASKA PENINSULA (275) 23:37: B E ALASKA PENINSULA (275) 23:39: D E ALASKA PENINSULA (275) 23:42: D E ALASKA PENINSULA (275) 23:53: D E ALASKA PENINSULA (276) 00:12: D E ALASKA PENINSULA (276) 00:14: D E ALASKA PENINSULA (276) 00:21: D E ALASKA PENINSULA (276) 00:21: D E ALASKA PENINSULA (276) 00:27: G D E SOUTH OF ALASKA 13

17 (276) 00:57: D E ALASKA PENINSULA (276) 00:58: D E ALASKA PENINSULA (276) 01:10: D E ALASKA PENINSULA (276) 01:11: B E CENTRAL ALASKA (276) 01:26: D E ALASKA PENINSULA (276) 01:28: D E ANDREANOF IS., ALEUTIAN IS (276) 01:40: C E ALASKA PENINSULA (276) 01:51: C E ALASKA PENINSULA (276) 01:51: B E ALASKA PENINSULA (276) 02:01: C E ANDREANOF IS., ALEUTIAN IS (276) 02:03: B E ALASKA PENINSULA (276) 02:06: C E ALASKA PENINSULA (276) 02:07: B E ALASKA PENINSULA (276) 02:08: D E ALASKA PENINSULA (276) 02:09: D E ALASKA PENINSULA (276) 02:19: D E ALASKA PENINSULA (276) 02:21: D E CENTRAL ALASKA (276) 02:25: A E ANDREANOF IS., ALEUTIAN IS (276) 02:31: D E ALASKA PENINSULA (276) 02:54: D E ALASKA PENINSULA (276) 02:57: C E ALASKA PENINSULA (276) 02:58: D E ALASKA PENINSULA (276) 03:08: G D E GULF OF ALASKA (276) 03:20: D E CENTRAL ALASKA (276) 03:51: D E ALASKA PENINSULA (276) 03:54: D E ALASKA PENINSULA (276) 04:10: D E ANDREANOF IS., ALEUTIAN IS (276) 04:30: D E ALASKA PENINSULA (276) 04:34: D E CENTRAL ALASKA (276) 04:48: D E ALASKA PENINSULA (276) 05:01: D E ALASKA PENINSULA (276) 05:28: C E CENTRAL ALASKA (276) 05:30: N/A B E SOUTHERN ALASKA (276) 05:34: D E CENTRAL ALASKA (276) 05:44: A E CENTRAL ALASKA (276) 06:01: A E CENTRAL ALASKA (276) 06:04: D E ALASKA PENINSULA (276) 06:11: D E ALASKA PENINSULA (276) 06:19: C E ALASKA PENINSULA (276) 06:30: D E ALASKA PENINSULA (276) 06:35: D E ALASKA PENINSULA (276) 06:42: D E ALASKA PENINSULA (276) 06:51: C E ALASKA PENINSULA (276) 06:59: A E CENTRAL ALASKA (276) 07:28: A E CENTRAL ALASKA (276) 07:40: A E CENTRAL ALASKA (276) 07:40: A E SOUTHERN ALASKA (276) 07:42: C E ALASKA PENINSULA (276) 07:43: D E ALASKA PENINSULA (276) 07:59: B E CENTRAL ALASKA (276) 08:08: C E ALASKA PENINSULA (276) 08:18: C E ALASKA PENINSULA (276) 08:22: C E CENTRAL ALASKA (276) 08:29: C E ALASKA PENINSULA (276) 08:38: C E ALASKA PENINSULA (276) 09:15: B E ANDREANOF IS., ALEUTIAN IS (276) 09:44: C E ALASKA PENINSULA (276) 09:53: B E ALASKA PENINSULA (276) 09:55: D E ANDREANOF IS., ALEUTIAN IS (276) 10:10: G D G SOUTHEASTERN ALASKA (276) 10:33: C E ALASKA PENINSULA (276) 10:34: A E ALASKA PENINSULA (276) 10:45: G D E SOUTH OF ALASKA (276) 10:56: C E ALASKA PENINSULA (276) 11:08: C E ALASKA PENINSULA (276) 11:12: D E SOUTHERN ALASKA (276) 11:18: C E ALASKA PENINSULA 14

18 (276) 11:32: C E ALASKA PENINSULA (276) 11:37: D E ALASKA PENINSULA (276) 11:48: A E SOUTHERN ALASKA (276) 11:50: C E ALASKA PENINSULA (276) 11:59: C E ALASKA PENINSULA (276) 12:00: G D E ALASKA (276) 12:14: B E SOUTHERN ALASKA (276) 12:37: C E ALASKA PENINSULA (276) 12:40: C E ALASKA PENINSULA (276) 12:45: C E ALASKA PENINSULA (276) 12:52: A E CENTRAL ALASKA (276) 12:57: C E ALASKA PENINSULA (276) 13:02: D E ALASKA PENINSULA (276) 13:02: C E ALASKA PENINSULA (276) 13:36: B E ALASKA PENINSULA (276) 13:40: D E ALASKA PENINSULA (276) 13:41: D E CENTRAL ALASKA (276) 13:48: D E ALASKA PENINSULA (276) 14:06: A F KODIAK ISLAND REGION Felt in Homer and Kodiak. Maximum intensity IV (276) 14:21: C E UNIMAK ISLAND REGION (276) 14:25: C E ALASKA PENINSULA (276) 14:30: D E ALASKA PENINSULA (276) 14:35: C E ALASKA PENINSULA (276) 14:50: B E ALASKA PENINSULA (276) 14:55: D E KODIAK ISLAND REGION (276) 14:56: D E ALASKA PENINSULA (276) 14:56: C E ALASKA PENINSULA (276) 15:08: D E ALASKA PENINSULA (276) 15:17: D E ALASKA PENINSULA (276) 15:18: C E CENTRAL ALASKA (276) 15:25: C E ALASKA PENINSULA (276) 15:25: C E CENTRAL ALASKA (276) 15:32: C E ALASKA PENINSULA (276) 15:40: C E ALASKA PENINSULA (276) 15:42: D E SOUTHERN ALASKA (276) 15:47: B E ALASKA PENINSULA (276) 15:49: C E ALASKA PENINSULA (276) 16:06: C E ALASKA PENINSULA (276) 16:36: D E ALASKA PENINSULA (276) 17:00: C E ALASKA PENINSULA (276) 17:21: C E ALASKA PENINSULA (276) 17:24: D E ANDREANOF IS., ALEUTIAN IS (276) 17:40: C E ALASKA PENINSULA (276) 18:09: D E ALASKA PENINSULA (276) 18:09: C E ALASKA PENINSULA (276) 18:12: A E SOUTHEASTERN ALASKA (276) 18:15: C E ALASKA PENINSULA (276) 18:17: C E ALASKA PENINSULA (276) 18:19: C E ALASKA PENINSULA (276) 18:32: D E ALASKA PENINSULA (276) 18:38: D E ANDREANOF IS., ALEUTIAN IS (276) 19:02: A E CENTRAL ALASKA (276) 19:25: G A G SOUTHEASTERN ALASKA (276) 19:31: D E UNIMAK ISLAND REGION (276) 19:35: D E ALASKA PENINSULA (276) 19:38: D E ALASKA PENINSULA (276) 20:05: B a FOX ISLANDS, ALEUTIAN IS (276) 20:05: C E ALASKA PENINSULA (276) 20:23: C E ALASKA PENINSULA (276) 20:37: D E ALASKA PENINSULA (276) 21:22: C E SOUTHERN ALASKA (276) 21:29: G A G SOUTHEASTERN ALASKA (276) 21:45: C E ALASKA PENINSULA (276) 21:49: D E ALASKA PENINSULA (276) 22:21: A E CENTRAL ALASKA (276) 22:46: D E ALASKA PENINSULA (276) 22:46: D E ALASKA PENINSULA 15

19 (276) 22:48: D E ALASKA PENINSULA (276) 22:51: B E ALASKA PENINSULA (276) 23:05: D E ALASKA PENINSULA (276) 23:07: D E ALASKA PENINSULA (276) 23:09: D E ALASKA PENINSULA (276) 23:15: C E SOUTHEASTERN ALASKA (276) 23:31: C E ALASKA PENINSULA (276) 23:47: C E ALASKA PENINSULA (276) 23:51: B E SOUTHERN ALASKA (277) 00:08: G A G SOUTHEASTERN ALASKA (277) 00:12: A E CENTRAL ALASKA (277) 00:17: A E CENTRAL ALASKA (277) 00:48: D E FOX ISLANDS, ALEUTIAN IS (277) 00:58: B E ALASKA PENINSULA (277) 01:17: B E ALASKA PENINSULA (277) 01:36: B E SOUTHERN ALASKA (277) 01:47: G A E CENTRAL ALASKA (277) 02:07: B E KODIAK ISLAND REGION (277) 02:17: B E ALASKA PENINSULA (277) 02:27: B E ALASKA PENINSULA (277) 02:29: C E ALASKA PENINSULA (277) 02:51: D E ALASKA PENINSULA (277) 02:57: A E SOUTHEASTERN ALASKA (277) 02:58: B E ALASKA PENINSULA (277) 03:21: D E ALASKA PENINSULA (277) 03:33: A E CENTRAL ALASKA (277) 03:36: A E CENTRAL ALASKA (277) 03:38: A E CENTRAL ALASKA (277) 03:51: A E ALASKA PENINSULA (277) 04:01: A E CENTRAL ALASKA (277) 04:51: B E FOX ISLANDS, ALEUTIAN IS (277) 05:03: A E CENTRAL ALASKA (277) 05:05: C E ANDREANOF IS., ALEUTIAN IS (277) 05:16: D E SOUTHEASTERN ALASKA (277) 05:19: A E CENTRAL ALASKA (277) 05:25: A E CENTRAL ALASKA (277) 05:34: A E KENAI PENINSULA, ALASKA (277) 06:14: A E CENTRAL ALASKA (277) 06:19: C E UNIMAK ISLAND REGION (277) 06:25: B E ALASKA PENINSULA (277) 06:53: A E CENTRAL ALASKA (277) 06:59: A E KODIAK ISLAND REGION (277) 07:09: A E CENTRAL ALASKA (277) 07:15: A E KODIAK ISLAND REGION (277) 07:38: A E CENTRAL ALASKA (277) 07:53: A E SOUTHERN ALASKA (277) 07:58: A E CENTRAL ALASKA (277) 08:01: A E SOUTHERN ALASKA (277) 08:08: A E CENTRAL ALASKA (277) 08:25: A E ALASKA PENINSULA (277) 08:28: C E SOUTH OF ALASKA (277) 08:39: A E KODIAK ISLAND REGION (277) 09:20: G A G SOUTHEASTERN ALASKA (277) 09:26: D E ALASKA PENINSULA (277) 10:09: A E CENTRAL ALASKA (277) 10:11: A E CENTRAL ALASKA (277) 10:26: C E ALASKA PENINSULA (277) 10:59: C E ALASKA PENINSULA (277) 11:14: A E KENAI PENINSULA, ALASKA (277) 11:21: G A G SOUTHEASTERN ALASKA (277) 11:45: A E CENTRAL ALASKA (277) 11:49: D E ALASKA PENINSULA (277) 11:55: B E ALASKA PENINSULA (277) 12:16: B E CENTRAL ALASKA (277) 12:19: A E ALASKA PENINSULA (277) 12:42: A E ALASKA PENINSULA (277) 12:44: D E ALASKA PENINSULA 16