用拉萨点大地测量资料检测青藏高原地壳的增厚

Present-day Crust Thickness Increasing beneath the Qinghai-Tibetan Plateau by Using Geodetic Data at Lhasa Station

青藏高原地壳的隆升与增厚,是一个复杂的热点问题。印度板块和欧亚板块的碰撞挤压导致地壳的隆升与增厚,已被地质、构造学等方面资料证实,但利用大地测量资料定量确定高原地下地壳增厚速率的很少。基于此,利用高精度绝对重力测量资料及GPS结果定量检测高原拉萨点地下地壳增厚速率((3.9±0.8)cm/a),并给出简单的动力学模型,研究表明高原地下物质亏损,地壳增厚。

The crust of Tibetan Plateau is still uplifting and thickening nowadays by the collision between the Indian plate and Eurasian plate which revealed by the geological and tectonic results,it is also a complex and hot problem which has been studying by global geoscientists.However,almost no quantitative evidence shows whether the plateau is still uplifting or thickening.In this paper we present geodetic evidence of mass loss beneath the Tibetan Plateau and increasing crust thickness which is 3.9±0.8 cm/a by using high accuracy absolute gravity data and the authoritative GPS measurements results,finally we give a simple geodynamic model illustrating crustal thickening of the Tibetan Plateau.