不同质的板块热脱水驱动温暖的俯冲区地震
Ye Zhu1,2, Yingfeng Ji3,4, Lijun Liu5,6
1State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China.
Scientific reports
|November 30, 2023
概括
在瓦努阿图等温暖的俯冲区,动态热脱水,而不仅仅是温度,驱动强烈的地震. 这一过程与潜水板中的矿物质变化有关,解释了大量的地震性.
科学领域:
- 地质物理学 地质物理学
- 构造学 构造学 构造学 构造学
- 地震学 地震学
背景情况:
- 变化的热体制会影响寒冷的大冲击时的地震性.
- 在瓦努阿图等温暖的俯冲区解释地震性是具有挑战性的,因为高温.
- 了解热结构是解释这些地区构造活动的关键.
研究的目的:
- 为了澄清控制瓦努阿图构造性地震的热结构.
- 为了研究热条件和地震性之间的关系,在一个温暖的俯冲区.
- 确定瓦努阿图潜水系统中地震性的主要驱动因素.
主要方法:
- 构建一个3D热力学模型.
- 对潜水板的热结构进行分析.
- 地震性与板面接口热过程的相关性.
主要成果:
- 揭示了一个异质的降温板块,温度从300°C到900°C以上.
- 确定了潜伏地震性和板面接口之间的强烈相关性,特别是当动态热脱水发生时.
- 观察到,水合玄武岩转化为生态岩石有助于强烈的地震和滑坡.
- 他指出,多阶段的矿物学变形影响了巨型岩石的稳定性,并产生了大型的板间事件.
结论:
- 薄板热脱水是影响温暖的潜水系统中潜水地震分布的更重要的因素,而不是薄板温度.
- 沉浮板块内的矿物质变化在产生大型地震事件中起着至关重要的作用.
- 动态热脱水过程对于理解温暖的俯冲区的地震性至关重要.
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