在Altyn Tagh断层沿线的地震间压力积累速度和风格的变化
Lin Shen1,2, Andrew Hooper3, John R Elliott3
1COMET, School of Earth and Environment, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, United Kingdom. lshen@ldeo.columbia.edu.
Nature communications
|August 11, 2024
概括
沿着阿尔廷塔格断层 (ATF) 的应变局部有很大的差异,与其他主要的冲滑断层不同. 这种由地质和热流影响的变化会影响地震危险评估.
科学领域:
- 构造学 构造学 构造学 构造学
- 地质物理学 地质物理学
- 遥感 遥感 遥感 遥感
背景情况:
- 主要的冲击滑动断层通常在不同岩石强度之间的风学边界形成狭窄的剪切区域.
- 了解压力局部化对于地震危险评估至关重要.
研究的目的:
- 为了研究沿着长达1600公里的Altyn Tagh断层 (ATF) 的应变分布和滑动率变化.
- 确定控制剪切区域宽度的因素及其对断层行为和地震危害的影响.
主要方法:
- 使用交叉测量合成孔径雷达 (InSAR) 来推导整个Altyn Tagh断层的速度场.
- 分析了沿断层的应变分布和滑动率.
主要成果:
- 沿着ATF的压力局部化非常可变,一些部分显示集中压力,而其他部分分布在广泛的剪切区域 (>100公里) 上.
- 沿着ATF的滑动速度各不相同,从西部到中部部分下降,在东部增加 (范围从7.2 ± 1.4毫米/年到11.6 ± 1.6毫米/年).
- 可变的剪切区宽度与地质变化和热流有关,亚平行断层影响变形场.
结论:
- 阿尔廷塔格断层表现出复杂的应变局部化模式,偏离了典型的狭窄剪切区域模型.
- 地质变化和热流显著影响沿主要冲滑断层的剪切区域的宽度.
- 准确地描述广域应变率对于强大的地震危险评估至关重要,突出了亚平行断层系统的作用.
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