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Source mechanism of February 4, 1965, Rat Island earthquake

Wu, Francis T. and Kanamori, Hiroo (1973) Source mechanism of February 4, 1965, Rat Island earthquake. Journal of Geophysical Research, 78 (26). pp. 6082-6092. ISSN 0148-0227. doi:10.1029/JB078i026p06082.

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The Rat Island earthquake of February 4, 1965 (origin time 05h 01m 21.8s, h = 40 km), is one of the largest earthquakes recorded in recent years. On the basis of the radiation patterns and the amplitudes of the great circle Rayleigh and Love waves, the earthquake is found to have the following characteristics: fault plane dip, 18°; fault plane dip direction, N19°E; rupture propagation direction, N51°W; rupture propagation velocity, 4.0 km/sec; fault length, 500 km; moment, 1.4 × 10^(29) dynes cm; stress drop, 30 bars; and average dislocation, 2.5 meters. It is interesting to observe that the attitude of the fault plane and the general features of this earthquake are similar to those of the 1963 Kurile earthquake (Kanamori, 1970a) and the 1964 Alaskan earthquake (Kanamori, 1970b). The first 35 sec of P waves were also well recorded at many stations. The wave forms suggest a multiple-event nature of the earthquake for at least the initial 35 sec. By using the relative location method, the events were located progressively south of the initial hypocenter. It seems plausible that the earthquake started off at depth, first propagated southward, and then westward along the Aleutian arc. Owing to the long-period nature of the surface waves, only the average feature of the fault is seen, and P waves reveal some of the detailed initial behavior.

Item Type:Article
Related URLs:
URLURL TypeDescription
Wu, Francis T.0000-0003-4529-9862
Kanamori, Hiroo0000-0001-8219-9428
Additional Information:© 1973 American Geophysical Union. (Received June 26, 1972; revised May 16, 1973.)
Issue or Number:26
Record Number:CaltechAUTHORS:20150810-161941909
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Official Citation:Wu, F. T., and H. Kanamori (1973), Source mechanism of February 4, 1965, Rat Island earthquake, J. Geophys. Res., 78(26), 6082–6092, doi:10.1029/JB078i026p06082.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:59374
Deposited By: George Porter
Deposited On:11 Aug 2015 15:20
Last Modified:10 Nov 2021 22:19

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