美国西部的板内变形是由复杂的石灰岩层结构控制的
1State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China.
Nature communications
|May 9, 2024
概括
美国西部复杂的石质层结构驱动着构造变形和地震. 层流与石层厚度变化相互作用,是局部地运动和地震性的关键机制.
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
- 地球科学 地球科学 地球科学
背景情况:
- 美国西部是一个高度构造活跃的地区,有显著的地变形.
- 大陆内部变形归因于板块边界力,石层体力和地幔流动,但它们的相对重要性仍在争论中.
- 之前的研究由于对地和地幔结构的不一致假设而面临限制.
研究的目的:
- 量化估计美国西部地变形.
- 调查板内部地震和地质测量运动的驱动机制.
- 通过结合现实的3D岩层结构来协调关于大陆内部变形的相互矛盾理论.
主要方法:
- 利用了一个完全动态的三维建模框架.
- 综合数据同化,同时计算石层和对流地幔动态.
- 占美国西部现实的三维岩层结构.
主要成果:
- 证明了复杂的石质层结构在控制板内变形中的关键作用.
- 确定了层流和石层厚度阶段之间的相互作用作为关键驱动因素.
- 局部地变形和地震性受到这些相互作用的显著影响,特别是在盆地和范围边界.
结论:
- 复杂的石层结构对于控制美国西部的构造活动至关重要.
- 地幔动力学和石质层变化之间的相互作用为观察到的变形模式提供了更准确的解释.
- 这项研究提供了一个精细的了解驱动动力地震性和地质运动在构造活跃的大陆内部的力量.
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