在日本的坎托盆地地震地面运动的传播,日本
1Earthquake Research Institute, University of Tokyo, Tokyo 113-0032, Japan. inquiry@taro.eri.u-tokyo.ac.jp
概括
一次5.7级地震揭示了地震波如何穿过坎托盆地. 表面波在盆地边缘折射,盆地内部的速度较慢会影响波浪传播模式.
科学领域:
- 地震学 地震学
- 地震工程的工程是地震工程.
- 地质物理学 地质物理学
背景情况:
- 了解地震波传播对于地震危险评估至关重要.
- 沉积盆地可以在地震期间显著改变地面运动特征.
研究的目的:
- 为了分析长期地面运动在坎托沉积盆地内的传播.
- 为了研究盆地边缘表面波折现现象.
主要方法:
- 利用了384个强大地面运动仪器的数据.
- 记录了东京附近5.7级地震的地面运动.
- 视觉化了在坎托盆地内的地震波传播模式.
主要成果:
- 观察了在托盆地边缘表面波的折射.
- 证明折射波是斜移动的,而不是直接从震中移动.
- 与周边地区相比,在盆地内确定了较慢的表面波传播速度.
- 展示了折射波如何调和盆地和周边地区之间的速度差异.
结论:
- 该研究可视化了沉积盆地中复杂的地震波行为.
- 在盆地边缘的表面波折是影响地面运动的关键因素.
- 折射到来在托盆地边缘附近特别占主导地位.
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