“1965 Rat Islands earthquake”的意思、由来-开放百科全书

The 1965 Rat Islands earthquake occurred at 05:01 UTC, on 4 February (19:01, 3 February local time^[1]). It had a magnitude of 8.7 and triggered a tsunami of over 10 m on Shemya Island,^[1] but caused very little damage.

Tectonic setting

The Rat Islands form part of the Aleutian Islands, a chain of volcanic islands forming an island arc, that results from the subduction of the Pacific Plate beneath the North American Plate. This plate boundary, the Alaska-Aleutian megathrust, has been the location of many megathrust earthquakes.

Characteristics

The 1965 Rat Islands earthquake share common features with the 1963 Kuril Islands earthquake and the 1964 Alaska earthquake.^[2]

Earthquake

The earthquake was associated with a 600 km long rupture along the plate boundary, based on the distribution of aftershocks.^[3] The pattern of energy release suggest the presence of three asperities along the plate interface, each causing a pulse of moment release. Modelling of the tsunami supports the idea that the earthquake consisted of three sub-events, related to three structural 'blocks' within the overriding plate.^[4]

The main shock was followed by an earthquake of magnitude 7.6 nearly two months later, that triggered a small tsunami.^[5] This was not an aftershock, but a normal fault event within the outer rise of the subducting plate, triggered by the earlier event.^[6]

Tsunami

The tsunami had a maximum run-up height of 10.7 m on Shemya Island, 2.0 m at Amchitka Island, 1.6 m at Attu Island and 1.1 m in northern Kauai, Hawaii. It was also observed in Peru, Ecuador, Mexico, California, Japan and eastern Russia.^[5]

Damage

Flooding from the tsunami caused $10,000 worth of damage on Amchitka Island.^[1] Minor damage from the earthquake was recorded on both Attu and Shemya islands in the form of cracks in runways.

See also

References

1. ^¹{{cite web|url=https://earthquake.usgs.gov/earthquakes/states/events/1965_02_04.php |title=Historic Earthquakes Rat Islands, Alaska |last=USGS |date=26 October 2009 |accessdate=8 March 2010 |deadurl=yes |archiveurl=https://web.archive.org/web/20100116161303/http://earthquake.usgs.gov/earthquakes/states/events/1965_02_04.php |archivedate=16 January 2010 |df= }}
2. ^{{Cite journal|last=Wu|first=Francis T.|last2=Kanamori|first2=Hiroo|date=1973-10-09|title=Source mechanism of February 4, 1965, Rat Island earthquake|url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/JB078i026p06082|journal=Journal of Geophysical Research|language=en|volume=78|issue=26|pages=6082–6092|doi=10.1029/jb078i026p06082|issn=0148-0227}}
3. ^{{cite journal|doi=10.1029/90JB02092|last=Beck|first=S.L.|author2=Christensen D.H.|year=1991|title=Rupture Process of the February 4, 1965, Rat Islands Earthquake|journal=Journal of Geophysical Research|volume=96|issue=B"|pages=2205–2221|bibcode = 1991JGR....96.2205B }}
4. ^{{cite book|last=Johnson|first=J.M.|title=Tsunamigenic Earthquakes and Their Consequences|editor=Dmowska R. & Saltzman B.|series=Advances in Geophysics|volume=39|year=1999|pages=28–55|chapter=Heterogeneous coupling along Alaska-Aleutians as inferred from Tsunami, Seismic and Geodetic Inversions|isbn=978-0-12-018839-0|url=https://books.google.com/books?id=CZVn6MjyAHMC}}
5. ^¹²³{{cite web|url=http://www.ngdc.noaa.gov/nndc/struts/results?bt_0=1965&st_0=1965&type_17=EXACT&query_17=None+Selected&op_12=eq&v_12=&type_12=Or&query_14=AK&type_3=Like&query_3=&st_1=&bt_2=&st_2=&bt_1=&bt_4=&st_4=&bt_5=&st_5=&bt_6=&st_6=&bt_7=&st_7=&bt_8=&st_8=&bt_9=&st_9=&bt_10=&st_10=&type_11=Exact&query_11=&type_16=Exact&query_16=&display_look=1&t=101650&s=1&submit_all=Search+Database|title=Search result for 1965 Alaska earthquakes|last=NGDC|accessdate=8 March 2010}}
6. ^{{cite journal|last=Abe|first=K.|year=1972|title=Lithospheric normal faulting beneath the Aleutian trench|journal=Physics of the Earth and Planetary Interiors|volume=5|pages=109–198|bibcode=1972PEPI....5..190A|doi = 10.1016/0031-9201(72)90091-X }}