中国及邻区岩石层密度三维结构

利用中国及邻区２×２Ｓ波速地震三维层析成像和３０’×３０’重力资料．首先采用密度差与Ｓ波速差的经验关系式，建立起中国及邻区的岩石层密度初始模型，再利用布格重力异常进行阻尼最小二乘法反演，得到该区岩石层三维密度分布结果．反演结果表明：１．中国地区密度异常分布与大地构造分区有着明显的相关性，高密度区对应古老地块，低密度区对应高原及山区，在不同块体边界存在着密度异常梯级带；２．岩石层地幔密度分布与地壳密度分布特征不一致．

THREE DIMENSIONAL DISTRIBUTION OF LIOTHSPERIC DEN8rrY BENEATH THE CHINA AND ITS ADJACENT REGION

We have collected three ascensional S--wave tomographe data that grided by 2' x2' and practical gravity data grided by 30' x 30' in the area of China and its adjacentregions. Firstly, by using the relative formula of between difference of density and difference of S--wave speed, founding the preliminary model of density in China and its adjacent regions. Then inversing density anomaly using Bouguc gravity data by means or theleast square method. The. results show: 1. Chinese distribution of density anomaly is obviously relative to the teCtonic. Higher density region corresponds with old terse, lower density corresponds plateau and mountain region. There are density anomaly gradients alongthe boundaries of differential tectonic bodies. 2. The distribution of mantle density is notagree with the distribution of crustal density.