Abstract: Using 2-D velocity structure from interpretation of DSS data of Yingxian-Zibo profile we present preliminary basic model.The values of gravity anomaly are calculated and the 2-D block density distribution is inversed making use of the block 2-D body mdel of any polysonal section.The computed results show that the detachment between the upper and the middle crusts is an obvious density interface.The strong velocity gradient,i.e.the crust-mantle transition zone in the bottom of the lower crust is a high density layer and the lower-velocity block within the middle-lower crusts beneath Wutai Mt.is a lower-density block.

Key words: Two-dimensional model, Density-inteface inversion, Detachment

摘要： 利用应县～淄博地震测深解释的二维速度结构,并将速度值转换为密度值,提供初始基本模型。运用任意多边形截面的块状二度体模型计算重力异常值,反演二维块状密度分布。计算结果表明：上、中地壳之间的滑脱面是一较明显的密度界面；下地壳底部的强速度梯度层──壳幔过渡带是一高密度层；五台山下部中、下地壳内的低速度块体是低密度块体。

关键词: 二维模型, 密度界面反演, 滑脱面