HR: 1340h
AN: S23A-1110    [Abstracts]
TI: New method for the evaluation of crustal structure analysis using OBS-control sources-MCS records
AU: Tanaka, T
EM: t_tanaka@jgi.co.jp
AF: JGI, Inc., 5-21-1 Ostuka, Bunkyo-ku, Tokyo, 112-0012, Japan
AU: * Kasahara, J
EM: kasahara_j@tairikudana.com
AF: JCSS Co. Ltd., NTC Bulid. 3F, 1-11-2, Kyobashi,Chiyoda-ku, Tokyo, 104-0031, Japan
AU: Kawamura, S
AF: NPG Co. Ltd., 2-2-12 Nakamagome, Ohta-ku, Tokyo, 143-0027, Japan
AU: Tsuruga, K
EM: tsuruga.k@tairikudana.com
AF: JCSS Co. Ltd., NTC Bulid. 3F, 1-11-2, Kyobashi,Chiyoda-ku, Tokyo, 104-0031, Japan
AU: Honda, F
AF: JGI, Inc., 5-21-1 Ostuka, Bunkyo-ku, Tokyo, 112-0012, Japan
AU: Iwaki, Y
AF: JGI, Inc., 5-21-1 Ostuka, Bunkyo-ku, Tokyo, 112-0012, Japan
AU: Iwaki, Y
AF: KGE, Co. Ltd., 2-11-15 Mita,Minato-ku, Tokyo, 108-8337, Japan
AU: Murase, K
AF: KGE, Co. Ltd., 2-11-15 Mita,Minato-ku, Tokyo, 108-8337, Japan
AU: Kubota, R
AF: KGE, Co. Ltd., 2-11-15 Mita,Minato-ku, Tokyo, 108-8337, Japan
AU: Unou, S
AF: JGI, Inc., 5-21-1 Ostuka, Bunkyo-ku, Tokyo, 112-0012, Japan
AU: Nishiyama, E
AF: KGE, Co. Ltd., 2-11-15 Mita,Minato-ku, Tokyo, 108-8337, Japan
AU: Tonoike, K
AF: JCSS Co. Ltd., NTC Bulid. 3F, 1-11-2, Kyobashi,Chiyoda-ku, Tokyo, 104-0031, Japan
AU: Nishizawa, A
AF: JHD, Japan Coast Guard, 5-3-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
AU: Kaneda, K
AF: JHD, Japan Coast Guard, 5-3-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
AB: In order to obtain on accurate best crustal velocity structure model, it is very important to make the best fit between the major phases identified in waveforms of the OBS wide-angle reflection and refraction survey data, and the MCS reflection sections. An ideal result is a crustal structure satisfying the waveform characteristics in both survey data. Recently, we have developed a new interactive software module (Kasahara et al., 2007) based on the gModeling-Pasteuph crustal structure analysis tool (Fujie et al.,m 2007) for OBS survey data to make a comparison between the OBS data and the MCS data in terms of time-offset distance sections. This integrated analyzing method computes the two-way travel times of normal incident waves from the analyzed crustal structure model. The software module in this method can superpose the time contours of the layers in the crustal structure model over the migrated time section of MCS. By an independent analysis, we also compute travel times of wide-angle reflections and superpose on the OBS seismic record sections. We also confirm the result of forward processing by the travel time inversion method and comparison to synthetic waveforms. Using a huge volume of real OBS-airgun seismic data and MCS reflection records around Japan and in the western Pacific, we confirmed that strong reflections from layers in the crust and the Moho seen in the OBS wide- angle reflection records are fairly consistent to the reflectors in the MCS section. Through the above integrated processes, we proved the correctness of the resultant crustal structure model. Such integrated analysis method may give the best crusal model using all available data.
DE: 3025 Marine seismics (0935, 7294)
DE: 3060 Subduction zone processes (1031, 3613, 8170, 8413)
DE: 7208 Mantle (1212, 1213, 8124)
DE: 7220 Oceanic crust
DE: 7240 Subduction zones (1207, 1219, 1240)
SC: Seismology [S]
MN: 2007 Fall Meeting