岩的特性照亮了缓慢和快速实验室地震的核化过程
David C Bolton1,2, Chris Marone3,4, Demian Saffer5
1University of Texas Institute for Geophysics, Jackson School of Geosciences, University of Texas, Austin, TX, USA. chasbolton19@gmail.com.
Nature communications
|June 29, 2023
概括
实验室地震研究表明,缓慢滑动事件显示一致的声学排放 (AE),而快速事件显示越来越多的AE相似性和在故障之前的旅行时间减少. 这突出了与滑动速度相关的核化过程中的差异.
科学领域:
- 地震地震学 地震学
- 地质物理学 地质物理学
- 实验室地震学 实验室地震学
背景情况:
- 了解地震活动和地震核形成对于早期预警和预测至关重要.
- 实验室的棒滑实验提供了可控的环境来研究地震过程.
- 声学发射 (Acoustic Emissions,简称AEs) 提供了关于地震事件的时空属性的见解.
研究的目的:
- 研究实验室前震和核化过程的时空特性.
- 为了探测缓慢和快速实验室地震 (实验室地震) 之间的核化差异.
- 为了将实验室前震的演变与断层滑动速度联系起来.
主要方法:
- 利用实验室棒滑实验中的高分辨率声辐射 (AE) 波形测量.
- 涵盖了从缓慢到快速的各种滑动率.
- 测量了AE之间的波形相似性和对对差异旅行时间 (DTT).
主要成果:
- 缓慢的实验室地震显示了小的DTT和高波形相似性,在整个地震周期中没有进化.
- 在快速实验室地震之前,波形相似性增加,并在地震周期晚期减少DTT.
- 观察到的AE凝聚与快速事件中故障前故障滑动速度的增加相关.
结论:
- 在缓慢与快速实验室地震的核化过程中存在关键差异.
- 实验室前震的时空进化与断层滑动速度直接相关.
- 这些发现有助于理解地震核和对地震危险评估的影响.
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