The dynamic characteristics of the ground in Lima, capital of Peru, specifically the amplification are investigated. By using the small and large microtremor array measurements we estimated the soil velocity profiles with depths to the bedrock in many cases. These profiles were used to estimate the amplification factors. Important results are the large amplification factors at EMO, VSV, CAL and CMA (La Molina, Villa El Salvador, El Callao and Bellavista district, respectively).

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A source model composed of super asperities was newly developed for the 2011 off the Pacific coast of Tohoku, Japan, earthquake and strong ground motions were simulated based on site amplification and phase characteristics. The constructed source model involves 9 super asperities, located off-the-coast of Miyagi through off-the-coast of Ibaragi. The agreement between the observed and calculated ground motions was quite satisfactory, especially for velocity waveforms (0.2-1.0 Hz) including near-source pulses.

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We considered a major factor of variability for the shakeability of long-period ground motion (LPGM) proposed by Yuzawa and Kudo (2011). The proposed empirical model can simply reproduce the response spectrum at a sediment site, combining the attenuation relation for the seismic basement and the site shakeability. However, the shakeability, evaluated as an average for different earthquakes, has a large standard deviation. It has large variability at around periods of 5 to 10 sec. We examined the factors that affect the variability for the shakeability, in order to improve the accuracy of the prediction of LPGM in the Kanto basin. As a result, we found that the period characteristics of the shakeability at each earthquake are dependent on the location of earthquake source. The major factor that affected the variability of the shakeability was the surface wave propagation in Kanto basin. In addition, we showed that the shakeability revaluated for limited regions improves the prediction accuracy of response spectrum of LPGM.

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Evaluation with high accuracy of ground motion at a damaged site is very important to analyze collapse mechanism of wooden houses. A serious disaster occurred during the 2011 Nagano-Niigata Border Earthquake. However, there were no strong motion observation stations at the wooden house damage sites during this earthquake. In this study, the seismic waveform at Yokokura Village, where a lot of wooden house damage occurred, was estimated based on empirical site amplification and phase effects. The estimated seismic waveform will be useful for rational safety assessment of wooden houses.

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