摘要
本文参考二维速度剖面资料，采用变密度组合体重力模型、自动拟合的方法，计算了海城—敖汗旗—巴彦查于剖面的密度分层结构。按壳、幔岩性变化特征分析，地壳大致具有三层结构，各层岩性呈交互混合的渐变过渡状态，由上到下，岩性无严格的地质分界。区内莫霍面的起伏不大，不是引起重力异常变化的主要原因。决定重力异常形态特征的主要因素是地壳与地幔物质的不均匀分布及层间的结构组合关系。这项研究结果对该区的地质构造和矿产预测提供了新的依据。
Abstract
Having consulted data of the two-dimensional velocity profile, the authors calculated the density layering structure along the Haicheng-Aohanqi-Bayanc-hagan section by using gravity model of variable density combinational body and automatic fitting method. According to an 'analysis of the lithologic variation characteristics of the crust and the mantle, it is held that the crust is basically characterized by the three-layer structure and that these layers are lithologically mixed with each other and show progressive and transitional relationship without distinct lithologic boundaries. The Moho in this region shows no obvious undulation which hence is not the main cause for variation in gravity anomalies. It is mainly the inhornoganeous distribution of the crus-tal and mantle materials and the layered structure that determine the shapes of gravity anomalies. The results of this research provide new basis for prognosis of geological structures and ore resources in this region.
出处
《物探与化探》
CAS
CSCD
1990年第1期1-8,共8页
Geophysical and Geochemical Exploration
