概括
重力异常与上层地幔地震速度的相关性在西欧亚和东欧亚之间有所不同. 位于欧亚大陆东部的低粘度区域.
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:
- 欧亚大陆北部的长波长重力异常与上层地幔地震速度异常相关.
- 这种相关性显示出西欧亚和东欧亚之间的标志反转.
研究的目的:
- 为了调查整个欧亚大陆的重力-地震相关性中观察到的信号逆转的原因.
- 了解上层地幔粘度在控制大陆内部变形中的作用.
主要方法:
- 分析整个北欧亚的重力异常数据.
- 与上层地幔的地震速度数据进行比较.
- 相关性分析以确定区域差异.
主要成果:
- 在重力和地震速度异常之间的相关性中发现了显著的横向变化.
- 这种变化与古老的坑和较年轻的带之间的地质边界相对应.
- 有证据表明,在欧亚大陆东部下面的顶层地幔中存在一个低粘度区域,而在西部则不存在.
结论:
- 低粘度上层地幔区域的存在或不存在解释了观察到的地球物理二分法.
- 上层地幔强度的侧向变化显著影响了大陆内变形的位置.
- 这项研究强调了地幔风学在塑造构造特征方面的重要性.
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