中国西部地区重力位能与板内变形动力

The Distribution of Gravitational Potential Energy and its Effect on Active Deformation in Western China

重力位能及其重力浮力是大陆板块内部重要的构造变形动力 .中国西部地区构造变形以垂向抬升、横向拉伸和压缩为主要特点 ,其重力位能及重力浮力分布 ,深刻影响着西部板内变形动力学机制 .地震学和重力学方法计算表明 :中国大陆西部蕴藏较大的重力位能 ,其中青藏高原重力位能在 2× 1 0 1 2 ～ 7× 1 0 1 2 N/m之间 .地壳重力位能变化导致的重力浮力 ,是板内变形的主要构造力 .在一定流变学条件下 。

The most active deformation in western China occurs in the Tibetan Plateau. Determining the distribution of gravitational potential energy and its effect on active deformation is fundamental to understanding the dynamics of continental deformation. According to the seisimic velocity and gravity data, we estimated the distribution of gravitational potential energy of Tibetan Plateau . Calculation shows that the gravitational potential energy(PE) is 2×10 12 ～7×10 12 N/m in Tibet Plateau. Its effect on active deformation in Tibetan Plateau was discussed. The computed results show that, given available constraints on rheology, gravitational potential energy are sufficeient to produce the wide variety of rates and styles of observed deformation.