在内蒙古大青山地区逆冲推覆构造所截切的英安岩中获得锆石207Pb/206Pb表面年龄加权平均值为1870±19Ma，认为英安岩为华北克拉通古元古代末—新元古代一次裂解事件的产物。同时，据安山岩锆石U-Pb年龄谐和度（102）较好的锆石206Pb/238U表面年龄436±4Ma及英安岩锆石U-Pb年龄谐和度（104）较好的锆石206Pb/238U表面年龄153±2Ma和160±2Ma，表明大青山地区逆冲推覆构造存在构造复活或构造追踪现象。这一认识为大青山地区逆冲推覆构造的研究积累了新的资料，提供了新的研究思路。%Weighted average zircon 207Pb/206Pb age of 1870±19Ma was obtained from the quartz-andesite cut by the thrusting struc⁃ture in Daqingshan area, Inner Mongolia. The quartz-andesite is the product of a breakup event between multi-stage rifting in the late Paleoproterozoic to Neoproterozoic period in North China. At the same time, according to the 206Pb/238U age of 436±4Ma from the concordant zircon (No. 06) of the basalt-andesite and the 206Pb/238U ages of 153±2Ma and 160±2Ma from the concordant zircons (No. 15 and 29) of the quartz-andesite, the structural revival and structural tracing phenomena exist in the thrusting tectonics in Daq⁃ingshan area. The results obtained by the authors have accumulated new information and provided new theoretical thinking for the study of thrusting tectonics in Daqingshan area.
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