在里奇克雷斯特断层区域的整个地震周期中,地的压力和损伤都在演变
Jared Bryan1, William B Frank1, Pascal Audet2
1Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.
概括
地震破裂区域显示持续的深波速度下降,表明累积损坏或永久变形. 这一发现影响了对地震周期动态和断层区演变的理解.
科学领域:
- 地质学
- 地震学
- 构造物理
背景情况:
- 地震释放了随着时间的推移通过断层和地演变而形成的构造压力.
- 地震波速监测地变形和应力, 但传统方法缺乏深层地的灵敏度.
研究的目的:
- 在2019年里奇克雷斯特地震序列中调查地波速和异形变化.
- 了解地震事件对断层区域的长期影响.
主要方法:
- 使用接收器功能来跟踪波速和异性变化.
- 分析了2019年里奇克雷斯特地震的数据.
主要成果:
- 在几个月内恢复的浅波速度下降.
- 在地震发生后持续数年的深度波速下降.
- 在整个地中也跟踪了异位变化.
结论:
- 持续下降的深海波速表明地震后变形或永久断层变化的损害累积.
- 这些发现对了解地震周期的能量预算和断层区域的演变有影响.
- 提出了两种情况:缓慢的地震间恢复或未成熟断层区域的永久变形.
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