京津及河北省中部的重力三维正演结果及其地质意义

使用重力资料推断解释地壳深部构造,关键在于浅层影响的消除。作者广泛收集整理了研究区的浅层地质资料,用三维重力正演方法逐层消除其影响,获得了一些较好的结果。在正演计算中发现,一些构造在下第三系以下已基本消失;而另一些构造却在此深度才逐渐显露。我们认为,浅层地质资料越完整准确,则三维重力正演计算的结果也将越好。在地壳深部构造的研究中,此方法与人工地震测深得到的地壳厚度基本一致,而花费却很低廉。它也是研究深浅构造关系的一种好方法。

THE RESULTS OF THE 3-D GRAVITATIONAL CALCULUS AND ITS GEOLOGICAL SIGNIFICANCE IN BEIJING - TIANJIN AREA AND THE CENTRAL PART OF HEBEI PROVINCE

The key to deduction of the deep crustal structure using gravity data is (o removing reasonably the influence of shallow layers Authors collected and sorted of the shallow geological data extensively in the studied area, then utilized a 3-D gravitational formula to remove its influence layer by layer and obtainned good results. Results indicate that some structures under the Eogene System basically disappeared and structures of other kinds gradually appeared. It is pointed out that the more complete and accurate shallow geological data are used, the better the results of the 3-D gravitational calculations can be obtained. This method can yield the results that is unified basically with the deep crustal structure inferred from deep seismic sounding. It is also a good and economical way for studying the relationship between shallow and deep structure.