Abstract
AbstractWe have investigated the slip distribution of the 15 November 2006 Central Kuril earthquake off Simushir Island using continuous GPS data. A dense GPS network on Hokkaido Island, northern Japan, and Sakhalin Island detected coseismic horizontal displacements of ~9 mm despite large epicentral distances of about 900–1200 km. Eastward displacements at the sites decrease to the south, and this spatial distribution feature constrains the slip on the three subfaults. Our data suggest that little slip has occurred in the southern and northern parts, but that a 6-m slip has occurred in the center of the focal region. This interpretation fits well with the detailed slip distribution inferred from teleseismic waveform inversions. The total seismic moment, 2.8 × 1021 N m, is approximately the value indicated using by the Global CMT solution. Our result implies that there remains a seismic gap between this event and the 1952 great Kamchatkan earthquake that is large enough for anM> 8 earthquake.
Highlights
The 15 November 2006 Central Kuril earthquake (GlobalCentroid Moment Tensor (CMT) Mw = 8.3) occurred off Simushir Island in the central Kuril Islands, at a location where the Pacific plate is subducting at a rate of 8.4 cm/yr (DeMets et al, 1994)
Remarks The present result suggests a large slip in the central part but small slips in the southern and northern parts of the aftershock region
Yamanaka (EIC seismological note, No 183, 06/11/15 Kuril Islands; available at: http:// www.eri.u-tokyo.ac.jp/sanchu/Seismo Note/2006/EIC183e .html) proposed a slip distribution model inferred from teleseismic body wave data
Summary
Focal mechanism indicates shallow dipping thrust faulting (Fig. 1), suggesting that this event was a typical interplate earthquake on the plate interface. This focal region corresponds to the last seismic gap along the Kuril subduction zone, which was first pointed out by Fedotov (1965). The amplitude of the eastward displacement decreased gradually to less than 1 mm on the southern part of Hokkaido Island These observations clearly indicate regular variations in the displacement vectors from north to south, reflecting the heterogeneous slip distribution on the seismic fault. Slip Distribution Estimation In order to estimate the slip distribution, we divided the aftershock region of the first week into three subfaults
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
