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本文利用地球物理场信息反映出地壳现代结构的特征和构造演化的观点,以重磁场为依据研究区域构造,划分出SN向断裂构造和西秦岭北缘EW向断裂构造呈立体交叉的格局,并以SN向断裂构造划分出具有构造差异的东、西秦岭,在西秦岭只有南、中两构造带,北秦岭构造带只在东秦岭,且是祁连东南延伸部分,并以电磁测深推断左行走滑张扭性渭河断裂作为祁连和北秦岭分界,以深地震测深反演的天水异常地幔或称壳幔混合带,探讨西秦岭北缘花岗岩类磁性南北分带的深部地质背景。
In this paper, we use the geophysical field information to reflect the characteristics of the crustal structure and tectonic evolution. Based on the gravity and magnetic field, we study the regional structure, and divide the SN-trending faults and the EW trending faults in the northern margin of the West Qinling. The East Qinling and West Qinling belts with structural differences are divided by SN fault structure. There are only south and middle tectonic belts in the West Qinling. The North Qinling belt is only in the East Qinling and is an extension of the southeast of the Qilian, and is extrapolated by electromagnetic sounding As the boundary between Qilian and North Qinling Mountains, the left-lateral extensional shear-Weihe fault is interpreted as the deep geological background of the granitic magnetic north-south belt in the northern margin of West Qinling with the exception of the Tianshui anomalous mantle or crust-mantle belt retrieved by deep seismic sounding.