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平均高度5 000m、表面积超过500万(原文如此,应为50万——译者注)平方公里的西藏高原是世界上最大的高原地形。喜马拉雅山脉不断上升,清晰地表明其驱动力与地球表面板块的全球性运动有关。然而,尽管该高原闻名于世,但对其主要特点如高原地下结构、变形方式与变形程度以及对全球构造学的影响还不甚清楚。理解构造学变形本质的一个中心问题是地壳和地幔中强度的垂直分布。Jin等在本期第669页上运用重力资料揭示了西藏地壳大规模褶皱的证据,并暗示在强硬的上地壳和上地幔之间有一软弱的下地壳层。青藏高原是始于4 500万年前的印度与欧业大陆碰撞的产物,结果使地壳厚度增加了一倍。以前解释与碰撞变形有关的地壳厚度的说法有三类,其中每一类都对地壳和上地幔的变形如何分布作了具体的预言。
The average height of 5 000 m, the surface area of more than 5 million (as the original text should be 500 000 - translator’s note) square kilometers of the Tibetan Plateau is the world’s largest plateau terrain. The rising Himalayas show clearly that their driving force is related to the global movement of the earth’s surface plate. However, although the plateau is famous around the world, its main features such as the underground structure of the plateau, the degree of deformation and deformation, and the impact on global tectonics are not yet known. A central issue to understand the nature of tectonic deformation is the vertical distribution of intensity in the crust and mantle. Jin et al., In page 669 of this issue, use gravity data to reveal evidence of massive folds in the Tibetan crust and suggest a weak underlying crust between the hard upper crust and the upper mantle. The Tibetan Plateau was the product of a collision between India and the European industrial continent 45 million years ago, resulting in a doubling of the crustal thickness. There have been three previous explanations of the thickness of the crust associated with collision deformation, each of which specifically predicts how the deformation of the crust and the upper mantle will be distributed.