Monthly Seismicity Report For September 1, 2017 to September 30, 2017

During September 2017, the Alaska Earthquake Center located 2912 earthquakes within the state. Of these, 16 were larger than or equal to magnitude 4.0. 8 events were felt. The largest earthquake located in Alaska this month was a moderate earthquake of magnitude 5.2 that occurred on September 11 at 21:52:06.708 UTC (September 11, 13:52:06.708 AKDT), 85 miles WSW of Adak.

Notable Events in Descending Order of Magnitude

September 11 at 21:52:06.708 UTC (September 11, 13:52:06.708 AKDT), Ml 5.2, 51.18N -178.30W, depth=27.2 km:
A moderate earthquake was located in ANDREANOF ISLANDS, ALEUTIAN IS..
This earthquake was:
85 miles (138 km) WSW of Adak
119 miles (192 km) E of Amchitka
189 miles (304 km) WSW of Atka

September 16 at 23:38:01.479 UTC (September 16, 15:38:01.479 AKDT), Ml 5.0, 59.86N -136.78W, depth=6.3 km:
A moderate earthquake was located in SOUTHEASTERN ALASKA. It was felt throughout southeast Alaska and in Whitehorse, Canada.
This earthquake was:
45 miles ( 72 km) NW of Klukwan
58 miles ( 94 km) WNW of Skagway
64 miles (102 km) NW of Haines

September 12 at 06:43:43.340 UTC (September 11, 22:43:43.340 AKDT), Ml 4.5, 55.20N -157.06W, depth=8.4 km:
A light earthquake was located in ALASKA PENINSULA.
This earthquake was:
91 miles (147 km) SE of Chignik
95 miles (152 km) ESE of Perryville
97 miles (157 km) SE of Chignik Lagoon

September 29 at 01:22:36.554 UTC (September 28, 17:22:36.554 AKDT), Ml 4.4, 51.86N -169.86W, depth=16.3 km:
A light earthquake was located in FOX ISLANDS, ALEUTIAN ISLANDS.
This earthquake was:
85 miles (138 km) SSW of Nikolski
97 miles (156 km) ESE of Amukta Pass
186 miles (299 km) E of Atka

September 5 at 08:23:59.124 UTC (September 5, 00:23:59.124 AKDT), Ml 4.4, 55.73N -152.92W, depth=11.8 km:
A light earthquake was located in SOUTH OF ALASKA.
This earthquake was:
96 miles (155 km) SSE of Akhiok
103 miles (165 km) S of Old Harbor
131 miles (211 km) SSE of Larsen Bay

September 9 at 19:22:47.475 UTC (September 9, 11:22:47.475 AKDT), Ml 4.4, 55.17N -157.11W, depth=36.8 km:
A light earthquake was located in ALASKA PENINSULA.
This earthquake was:
92 miles (148 km) SSE of Chignik
94 miles (152 km) ESE of Perryville
98 miles (158 km) SE of Chignik Lagoon

September 28 at 23:16:42.816 UTC (September 28, 15:16:42.816 AKDT), Ml 4.4, 51.45N -175.60W, depth=25.8 km:
A light earthquake was located in ANDREANOF ISLANDS, ALEUTIAN IS..
This earthquake was:
54 miles ( 87 km) ESE of Adak
79 miles (126 km) SW of Atka
165 miles (266 km) WSW of Amukta Pass

September 8 at 03:24:05.046 UTC (September 7, 19:24:05.046 AKDT), Ml 4.3, 52.27N -169.12W, depth=14.7 km:
A light earthquake was located in FOX ISLANDS, ALEUTIAN ISLANDS.
This earthquake was:
47 miles ( 76 km) SSW of Nikolski
122 miles (196 km) E of Amukta Pass
154 miles (248 km) SW of Unalaska

September 18 at 14:32:55.288 UTC (September 18, 06:32:55.288 AKDT), Ml 4.2, 51.56N -178.38W, depth=5.9 km:
A light earthquake was located in ANDREANOF ISLANDS, ALEUTIAN IS..
This earthquake was:
77 miles (124 km) WSW of Adak
112 miles (181 km) E of Amchitka
184 miles (296 km) WSW of Atka

September 19 at 14:49:35.319 UTC (September 19, 06:49:35.319 AKDT), Ml 4.2, 51.90N 177.98W, depth=137.2 km:
A light earthquake was located in RAT ISLANDS, ALEUTIAN ISLANDS.
This earthquake was:
51 miles ( 82 km) WNW of Amchitka
92 miles (148 km) ESE of Buldir Is
172 miles (277 km) ESE of Shemya

September 21 at 22:15:20.973 UTC (September 21, 14:15:20.973 AKDT), Ml 4.2, 62.78N -148.88W, depth=20.3 km:
A light earthquake was located in CENTRAL ALASKA. It was felt in Talkeetna.
This earthquake was:
42 miles ( 67 km) S of Cantwell
51 miles ( 81 km) NE of Talkeetna
53 miles ( 85 km) S of Denali Park

September 13 at 07:22:17.046 UTC (September 12, 23:22:17.046 AKDT), Ml 4.2, 62.90N -149.92W, depth=79.6 km:
A light earthquake was located in CENTRAL ALASKA. It was felt throughout southcentral Alaska.
This earthquake was:
40 miles ( 65 km) N of Talkeetna
45 miles ( 73 km) SW of Cantwell
54 miles ( 87 km) SE of Kantishna

September 30 at 21:15:06.013 UTC (September 30, 13:15:06.013 AKDT), Ml 4.2, 59.62N -152.24W, depth=84.3 km:
A light earthquake was located in SOUTHERN ALASKA. It was felt in Soldotna, Homer, and Anchorage.
This earthquake was:
18 miles ( 29 km) SW of Anchor Point
22 miles ( 35 km) NNW of English Bay
22 miles ( 35 km) NNW of Nanwalek

September 4 at 21:05:02.910 UTC (September 4, 13:05:02.910 AKDT), Ml 4.1, 60.68N -151.22W, depth=68.1 km:
A light earthquake was located in KENAI PENINSULA, ALASKA. It was felt throughout southcentral Alaska.
This earthquake was:
9 miles ( 14 km) N of Kenai
14 miles ( 23 km) NNW of Soldotna
18 miles ( 30 km) WNW of Sterling

September 16 at 01:34:46.235 UTC (September 15, 17:34:46.235 AKDT), Ml 4.0, 51.69N -170.32W, depth=41.5 km:
A light earthquake was located in FOX ISLANDS, ALEUTIAN ISLANDS.
This earthquake was:
85 miles (136 km) ESE of Amukta Pass
106 miles (170 km) SW of Nikolski
169 miles (272 km) E of Atka

September 11 at 20:40:49.314 UTC (September 11, 12:40:49.314 AKDT), Ml 4.0, 52.01N -173.34W, depth=45.0 km:
A light earthquake was located in ANDREANOF ISLANDS, ALEUTIAN IS..
This earthquake was:
39 miles ( 62 km) ESE of Atka
61 miles ( 99 km) WSW of Amukta Pass
141 miles (228 km) E of Adak

This report was compiled by M. Braun.

The data in this report are preliminary and subject to revision. Most of the earthquake parameters have been determined by the Alaska Earthquake Center, with supplemental data provided by the USGS National Earthquake Information Center, Box 25046, Denver Federal Center MS 967, Denver, CO 80225. The data are released on the condition that none of the cooperating agencies may be held liable for any damages resulting from its authorized or unauthorized use.

For more information on earthquakes and seismology, contact the AEC at (907)-474-7320.