实验证据表明,由无地震滑动引发的地震断裂是由无地震滑动引发的
1Laboratoire de Physique, Université de Lyon, Ecole Normale Supérieure de Lyon, CNRS, 46 allée d'Italie, Lyon, 69007, France.
Nature communications
|September 18, 2024
概括
地震断层的缓慢滑动事件可以作为破裂的核化中心,增加地震频率. 了解这些缓滑区域是如何演变的,对于减轻地震风险至关重要.
科学领域:
- 地质物理学 地质物理学
- 构造物理学 构造物理学
- 地震科学 地震科学 地震科学
背景情况:
- 地震断层通过快速破裂或缓慢滑动事件释放累积的构造压力.
- 缓慢滑动事件显著影响地震的发生,但它们的精确机制仍然不清楚.
- 缓慢滑动对摩擦锁定断层区域故障的影响尚不清楚.
研究的目的:
- 研究慢滑区域作为地震破裂的核化中心的作用.
- 了解故障异质性和正常负载如何影响慢滑行为.
- 阐明缓慢滑动影响地震核化动态的机制.
主要方法:
- 在剪切应力下模拟故障行为的实验室实验.
- 引入颗粒状材料以模拟实验室断层上的缓慢滑动区域.
- 测量对剪切的故障反应,包括剪切阻力和破裂动态的变化.
主要成果:
- 由断层异质性模拟的缓慢滑动区域,作为地震破裂的核化中心.
- 这种异质性的存在降低了断层的剪切阻力,引发了断裂.
- 慢滑区域的范围受正常负荷的影响,表明除了组成之外的因素至关重要.
结论:
- 缓慢滑动区域改变了破裂核化动态,可能增加地震频率.
- 断层异质性在启动地震断裂方面发挥着至关重要的作用.
- 考虑到慢滑区域在不同条件下的不断变化的性质,对于有效地减轻地震危险至关重要.
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