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IUGG XXIV General Assembly July 2-13, 2007 Perugia, Italy
(S) - IASPEI - International Association of Seismology and Physics of the Earth's
Interior
JSS002 Oral Presentation 1778
The Kuril Island Tsunamis of 15 November 2006 and 13 January 2007: A
comparative analysis
Dr. Richard Thomson
Department of Fisheries and Oceans Institute of Ocean Sciences
I.V. Fine, A.B. Rabinovich, E.A. Kulikov
Two major tsunamigenic earthquakes have recently occurred near the Central Kuril Islands . The trans-
Pacific tsunami generated by the Mw = 8.3 earthquake of 15 November 2006 was the largest since that
generated by the 1964 Alaska earthquake. Wave heights exceeding 1 m were recorded as far as the
Hawaiian Islands, Oregon, California and . Significant damage took place in the port of Crescent City (
California ) located roughly 6600 km from the source. Maximum waves recorded at this site were up to
177 cm. Marked tsunami signals were identified in records from the Kuril Islands, Japan, Alaska,
Canada, Peru, New Zealand and various Pacific islands. Two months later, on 13 January 2007, a Mw =
8.2 earthquake occurred in the same region with a source located slightly seaward from the source of
the November 2006 earthquake. Although weaker than the 2006 tsunami, the 2007 tsunami was also
clearly recorded at many sites in the Pacific Ocean, including the Kuril, Aleutian, and Hawaiian islands,
California and . Both tsunamis have been examined in detail using coastal tide gauges, bottom-pressure
open-ocean stations and satellite altimetry. Numerical models have formulated for both events.
Simulated tsunami wave forms were found to agree closely with the offshore island and deep-ocean
DART records. The energy flux of the waves was mainly directed southeastward toward the Hawaiian
Islands and . A pronounced feature of both tsunamis was their high-frequency content, with typical
wave periods from 5 to 20 minutes. Dispersion was found to play an important role in the propagation
and transformation of these waves. Despite their similarities, the two tsunamis were markedly different
and even had opposite polarity in that the first trans-Pacific wave for the first event was positive while
that from the second event was negative.
Keywords: kuril islands