Subsurface Structure in Japan Based on P and S waves Travel Time Analysis Using Genetic Algorithm in Japan Seismological Network

A. M. Miftahul Huda, Bagus Jaya Santosa



Experiment to obtain the subsurface structure in Japan is conducted using seismograms analysis of earthquakes in Japan. All 101 data was used from events in 2012, selected by a maximum depth of 60 km and magnitude between 4.2 to 5.5 Mj. Determination of 1-D subsurface structure is done by utilizing the inversion method with genetic algorithm approach. P wave and S wave velocity structure are determined based on arrival times at receiver. The crustal thickness is known of 33,66 km. P wave velocity for the upper and lower crust, are 6,03 km/s and 6,92 km/s, respectively, and velocity in the upper mantle is 8,18 km/s. S wave velocity for the upper and lower crust are given 3,38 km/s and 3,89 km/s respectively, and the velocity in the upper mantle is 4,59 km/s. If the range integrated to the stable parameter of velocity structure, it shows stable result and the subsurface structure has sufficiently high compatibility.


velocity structure, genetic algorithm, travel time, Japan seismological broadband

Full Text:



Billings, S. D., Sambridge, M. S., & Kennett, B. L. N. (1994). Errors in hypocenter location: picking, model, and magnitude dependence. Bulletin of the Seismological Society of America, 84(6), 1978–1990. Retrieved from

De Vasconcelos Lopes, A. E., & Assumpccão, M. (2011). Genetic algorithm inversion of the average 1D crustal structure using local and regional earthquakes. Computers & Geosciences, 37(9), 1372–1380. Retrieved from

Fukao, Y. (1977). Upper mantle P structure on the ocean side of the Japan—Kurile Arc. Geophysical Journal International, 50(3), 621–642. Retrieved from

Gomberg, J. S., Shedlock, K. M., & Roecker, S. W. (1990). The effect of S-wave arrival times on the accuracy of hypocenter estimation. Bulletin of the Seismological Society of America, 80(6A), 1605–1628. Retrieved from

Hirahara, K. (1986). 3-D Seismic Velocity Structure beneath Southwest Japan Revealed by Geotomography. Retrieved from

Hirose, F., Nakajima, J., & Hasegawa, A. (2008). Three-dimensional seismic velocity structure and configuration of the Philippine Sea slab in southwestern Japan estimated by double-difference tomography. Journal of Geophysical Research: Solid Earth (1978–2012), 113(B9). Retrieved from

Ishida, M., & Hasemi, A. H. (1988). Three-dimensional fine velocity structure and hypocentral distribution of earthquakes beneath the Kanto-Tokai district, Japan. Journal of Geophysical Research, 93(B3), 2076–2094. Retrieved from

Kanamori, H. (1967). Upper Mantle Structure from Apparent Velocities of P Waves Recorded at Wakayama Micro-Earthquake Observatory. Retrieved from

Kato, M., & Nakanishi, I. (2000). Upper mantle velocity structure in the western Pacific rim estimated from short-period recordings at Matsushiro Seismic Array System. EARTH PLANETS AND SPACE, 52(7), 459–466. Retrieved from

Kennett, B. L. N. (1991). The removal of free surface interactions from three-component seismograms. Geophysical Journal International, 104(1), 153–163. doi:10.1111/j.1365-246X.1991.tb02501.x

Lee, W. H. K., & Lahr, J. C. (1972). HYPO71 (revised): a computer program for determining hypocenter, magnitude, and first motion pattern of local earthquakes. US Department of the Interior, Geological Survey, National Center for Earthquake Research. Retrieved from

Matsubara, M., Obara, K., & Kasahara, K. (2008). Three-dimensional P-and S-wave velocity structures beneath the Japan Islands obtained by high-density seismic stations by seismic tomography. Tectonophysics, 454(1), 86–103. Retrieved from

Peng, Z. (2013). Introduction to Seismic Analysis Code (SAC). Retrieved from

Reading, A., Kennett, B., & Sambridge, M. (2003). Improved inversion for seismic structure using transformed, S-wavevector receiver functions: Removing the effect of the free surface. Geophysical research letters, 30(19), 1981. doi:DOI: 10.1029/2003GL018090

Saiga, A., Matsumoto, S., Uehira, K., Matsushima, T., & Shimizu, H. (2010). Velocity structure in the crust beneath the Kyushu area. Earth, Planets, and Space, 62, 449–462. Retrieved from

Santosa, B. J. (2012). One dimensional P wave velocity structure of the crust beneath west Java and accurate hypocentre locations from local earthquake inversion (Vol. 1454). Retrieved from

Wessel, P., & Smith, W. H. F. (1998). New, improved version of generic mapping tools released. Eos, Transactions American Geophysical Union, 79(47), 579. doi:10.1029/98EO00426

Zhao, D., Hasegawa, A., & Horiuchi, S. (1992). Tomographic imaging of P and S wave velocity structure beneath northeastern Japan. Journal of Geophysical Research: Solid Earth (1978–2012), 97(B13), 19909–19928. Retrieved from

Published by Department of Chemical Engineering University of Diponegoro Semarang
Google Scholar

IJSE  by is licensed under Creative Commons Attribution 3.0 License.