Alaska Earthquake Information Center, member of the Advanced National Seismic System (ANSS), funded by the State of Alaska, NOAA, and USGS. Located at the Institute of Geophysics of the University of Alaska Fairbanks, Alaska Earthquake Information Center receives data from more than 400 seismic sites. AEIC serves as the integration of all the seismic network in Alaska, as well as archiving and processing data from the West
Coast and Alaska Tsunami Warning Center located in Palmer, Alaska, (~ 20 sites), and the Alaska Volcano Observatory in Fairbanks and Anchorage office (~ 180 sites). All sites in the network operating system with real-time data acquisition at the Institute of Geophysics. This network is strengthened by three established Research Institute for Seismology (IRIS) sites, College, Kodiak Island, and adak, and two sites in the Eagle ANSS and Wrangell. Alaska Earthquake Information Center personnel locate and report about 22,000 earthquakes each year, and advise federal and state officials each major earthquake location and size within 30 minutes. In addition, the earthquake catalog produced by AEIC is the basis for seismic hazard studies, because they are the most important element in determining the level of earthquake source zones and seismicity. Alaska's population is about 600,000 and growing. Anchorage, almost totally destroyed in 1964 and rebuilt on unstable ground, now home to over 275,000 people. Other cities in Alaska (for example Fairbanks, Valdez, Seward, and Dutch Harbor) also has evolved over the years into a large population or undustrial center and facing the danger of a serious earthquake.
Trans-Alaska pipeline, across many areas of the seismically active country, the U.S. oil major domestic airlines and are at risk from a variety of potential earthquake sources, including the Denali Fault (intraplate faults longest in the country). Largest fishing industry in this country lies in the Aleutian Islands, and are vulnerable not only to a significant earthquake hazard, but also to volcanic eruptions and tsunamis from earthquake sources both local and remote. Alaska earthquake is the main source of the tsunamis that impact other areas of the United States and Pacific Rim countries. Seismic hazard in Alaska comes from several sources. The largest earthquake in the state caused by the subduction of the Pacific plate under Alaska. Three of the seven largest earthquakes in the 20th century occurred in Alaska (1957 Aleutian, 1964 Prince William Sound, and the 1965 Rat Islands). Although it is generally believed that large earthquakes are rare, with a recurrence time on the order of hundreds of years for individual segments, five large underthrusting event has occurred in Alaska since 1938. In addition, both the 1986 and 1996, Andreanof Islands Islands Delarof magnitude 8-class earthquake zone reruptured part of 1957, although only 29 and 39, respectively, had elapsed since the big event. In a recent evaluation of potential earthquake in Alaska, the researchers showed that some segments of the subduction zone may be ready to burst soon. Yakataga gap and the area between Kodiak Island and the Shumagin Islands is an area where magnitude 8 + events are expected. The second type of danger comes from a smaller earthquake measuring 6.8 to 8.0, which occurred in many areas in central and southcentral Alaska. These events, while the smaller, occur at more frequent intervals, and in a location that can not always be predicted. On average, Alaska has a magnitude 7.0 or greater earthquake about every two years. Same size as the recent California earthquakes, these events can cause major damage if they occur in populated areas or strategically sensitive. The third danger there is of many small events that often occur near populated areas. While these events are too small to cause extensive damage, they are relatively common and thus pose a continuous threat to urban areas. Plot below shows how many earthquakes are reported each year in Alaska and the Aleutian combined since 1970 (top) and magnitude earthuqake largest record for that year (below).
Earthquake Details
This event has been reviewed by a seismologist.
Magnitude 3.5
Date-Time
Tuesday, May 15, 2012 at 22:18:36 UTC
Tuesday, May 15, 2012 at 01:18:36 PM at epicenter
Location 51.885°N, 171.447°W
Depth 29 km (18.0 miles)
Region FOX ISLANDS, ALEUTIAN ISLANDS, ALASKA
Distances
192 km (120 miles) E (99°) from Atka, AK
211 km (131 miles) WSW (237°) from Nikolski, AK
357 km (222 miles) E (88°) from Adak, AK
1671 km (1039 miles) WSW (242°) from Anchorage, AK
Location Uncertainty horizontal +/- 5.2 km (3.2 miles); depth +/- 2.6 km (1.6 miles)
Parameters Nph= 14, Dmin=0 km, Rmss=0.92 sec, Gp= 0,
M-type=local magnitude (ML), Version=2
Source
Alaska Earthquake Information Center
Geophysical Institute, University of Alaska Fairbanks
Event ID ak10472501
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