Abstract
　The distributions of peak accelerations during the 1993 Kushiro-oki earthquake and the 1993 Hokkaido Nansei-oki earthquake are simulated by using simplified analytical procedure. Peak acceleration near the fault region is expressed as a function of the fault parameters and the relative collocation between the fault and the observation site. The acceleration at the bed rock level first was calculated, after which the Q-value of the path traveled and the amplification factor of the surface ground were introduced. To check the accuracy of the calculated peak accelerations we compared estimated values with observed values which were recorded at ports and meteorological observatories. The estimated values are in good agreement with the observed values. In the region near the fault for both earthquakes the maximum accelerations are more than 250 gal.

【キーワード】：最大加速度，震源域，１９９３年釧路沖地震，１９９３年北海道南西沖地震，増幅度
Key words: peak acceleration, fault region, 1993 Kushiro-oki earthquake, 1993 Hokkaido Nansei-oki earthquake, amplification factor

*山口大学工学部
Faculty of Engineering, Yamaguchi University
**京都大学防災研究所
Disas. Prev. Res. Inst., Kyoto University
***京都大学工学部
Faculty of Engineering, Kyoto University