The M7.9 Nepal earthquake of 25 April2015 had over 8, 500 fatalities and was the most destructive earthquake in Nepal since the Bihar-Nepal earthquake in 1934.In this study, we imaged the rupture process of this Nepal...The M7.9 Nepal earthquake of 25 April2015 had over 8, 500 fatalities and was the most destructive earthquake in Nepal since the Bihar-Nepal earthquake in 1934.In this study, we imaged the rupture process of this Nepal event by back-projecting the teleseismic P-wave energy recorded at the three regional networks in Alaska, Australia and Europe. The back-projection images of the three subarrays revealed that the Nepal earthquake propagated along the strike in a southeast direction over a distance of ～ 160–170 km with the duration of ～ 50–55 s. The rupture process was found to be a simple, unilateral event with a near constant velocity of 3.3 km/s.The beam power was mainly distributed in the geographic region just north of Kathmandu and the peak intensity for the source time function curve occurred at about 30 s. The earthquake was destructive due to its occurrence at shallow depth(～ 12–15 km) and the fact that the capital lies in a basin of soft sediment. Additionally, the resonance effect for the longer period waves that occurred in the Kathmandu valley led to destructive aggravation, impacting mainly the taller buildings.展开更多
基金supported by the National Natural Science Foundation of China (No.41604049)
文摘The M7.9 Nepal earthquake of 25 April2015 had over 8, 500 fatalities and was the most destructive earthquake in Nepal since the Bihar-Nepal earthquake in 1934.In this study, we imaged the rupture process of this Nepal event by back-projecting the teleseismic P-wave energy recorded at the three regional networks in Alaska, Australia and Europe. The back-projection images of the three subarrays revealed that the Nepal earthquake propagated along the strike in a southeast direction over a distance of ～ 160–170 km with the duration of ～ 50–55 s. The rupture process was found to be a simple, unilateral event with a near constant velocity of 3.3 km/s.The beam power was mainly distributed in the geographic region just north of Kathmandu and the peak intensity for the source time function curve occurred at about 30 s. The earthquake was destructive due to its occurrence at shallow depth(～ 12–15 km) and the fact that the capital lies in a basin of soft sediment. Additionally, the resonance effect for the longer period waves that occurred in the Kathmandu valley led to destructive aggravation, impacting mainly the taller buildings.
