Abstract: This paper discusses the method by which the regional anomaly can be abstracted.On the basis of making a series of upward continuation of the aeromagnetic data from Beijing-Tianjin and surrounding areas, it is proposed that the regional anomaly can be divided into two parts: the upper one and the lower one corresponding to the upper and lower crustal magnetic layers, respectively. According to the Pre-cambrian metamor-phic basement the study region can tectonically be divided into six blocks. Moreover, from the lower regional magnetic anomaly it can be derived that the lower magnetic layer may be largely affected by the thermal events related to the Mesozoic and Cenozoic magmatism. This paper also discusses the deep regional anomaly, presumably resulting from the rise of the Moho surface.

摘要： 本文对提取区域磁异常方法作了讨论。在对京津及周围地区航磁资料进行了一系列向上延拓基础上,提出区域磁异常可区分为上部区域异常及下部区域异常。它们分别与地壳的上、下磁性层对应。文中根据上部区域磁异常,对前寒武纪变质基底作了构造分区。根据下部区域磁异常,推测地壳下部磁性层受后期的中、新生代岩浆作用的影响很大。同时又探讨了第三类深部区域异常,推测其可能是莫霍面隆起所致。