在西藏地中通过磁研究检测出广泛存在的流体
1Department of Applied Geophysics, China University of Geosciences, Beijing, People's Republic of China.
概括
磁探测揭示了西藏高原中部和下部地的异常导电性,这表明部分融化或流体广泛存在. 这种高电导率表明西藏下面存在显著的地质活动.
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:
- 西藏高原在其中部和下部地表现出异常的电导率.
- 与西藏相比,稳定的大陆地区的地导电率明显较低.
研究的目的:
- 研究西藏地中高电导率的性质和影响.
- 了解部分融和流体在西藏高原构造学中的作用.
主要方法:
- 磁探测被用来绘制西藏高原电导率的地图.
- 综合导电性 (导电性) 值的分析.
主要成果:
- 西藏地的电导率在3000至20,000西门之间,远远超过稳定的大陆地区 (20-1000西门).
- 在西藏南部15-20公里深处存在一个高导电性层 (可能是部分融化/流体),在西藏北部30-40公里 (可能是部分融化).
结论:
- 普遍高的地导电强烈表明,在西藏地内有广泛的部分融化和/或水性流体.
- 富含液体的区域可能代表地弱的区域,促进变形和较低的地流动.
- 这些发现为西藏高原正在进行的演变和变形提供了关键的见解.
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