The Helanshan tectonic belt is located between the Alax massif and the Ordos Basin, and underwent multi-stage deformation from Proterozoic. The Zhuozishan Mountain in the northern of the Helanshan tectonic belt contained a complex structural style, and which recorded the abundant information on the evolution of the Alax massif, the Ordos Basin and the Paleo Asian Ocean. After a detailed outfield structural analyses, an outcome was get that the Zhuozishan Mountain underwent multi-stage of the deformation during the Mesozoic and Cenozoic. The first one was characterized by the NWW-trending folds formed in Triassic and the Pre-Triassic strata, indicating a NNE-direction compression in the Late Triassic. The second one was characterized by the NE-trending structures formed in the Jurassic and the Pre-Jurassic strata, indicating a NW-direction compression in the Late Jurassic. The third phase of the deformation was characterized by the dextral slip of the Huanghe fault and the 30° direction discrepancy of the earlier structures and paleostress field distributed in the both sides of the Huanghe fault. As the Cretaceous and the upper strata in the east of the Huanghe fault were stable as well as the previous paleomagnetism results, the third phase of the deformation was confined as the 30° anticlockwise rotation of the Ordos massif along the Huanghe fault in the Cenozoic.
Yang Xiangyang Dong Yunpeng Sun Shengsi Zhang Feifei Sun Jiaopeng Wang Zhining. Mesozoic-Cenozoic deformation characteristics of the Zhuozishan Mountain in the northern Helanshan tectonic belt[J]. Chinese Journal of Geology, 2018, 53(3): 799-818.