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二连盆地的构造反转事件一直有争议.为了查明二连盆地巴音都兰凹陷早白垩世期间反转构造的发育期次以及不同时期发生反转构造的动力机制,利用新处理的覆盖全凹陷的3D地震数据和钻井资料,识别并分析了研究区在裂陷期发育的4期正反转构造,分别对应阿三段沉积末期、阿四段沉积末期、腾一下段沉积末期以及腾二段沉积期.研究表明:研究区早白垩世岩浆底辟较为活跃,在阿三段、阿四段和腾一下段以及腾二段沉积末期均发育过岩浆底辟活动,并导致盆地局部发生构造正反转,而腾二段沉积期间除了发育岩浆底辟作用导致构造反转外,还发育左旋压扭活动,并导致构造正反转.因此,研究区在早白垩世发育了两种不同成因类型的正反转构造,这主要与二连盆地在早白垩世期间伊泽纳琦板块对欧亚大陆的俯冲和异常地幔隆升引起的岩浆底辟作用以及腾二段沉积期伊泽纳琦板块俯冲方向发生改变而导致的区域走滑作用密切相关.
The tectonic inversion event in Erlian Basin has been controversial for a long time.In order to find out the developmental stages of the inversion structure during the Early Cretaceous in the Bayan Dulan Sag in the Erlian Basin and the dynamic mechanism of inversion structure in different periods, Total depression 3D seismic data and drilling data, identifying and analyzing 4 periods of positive and negative inversion structures developed during the rifting period in the study area, corresponding to the sedimentary facies of the Asan Member, the sedimentary member of the Member A and the end of the Teng Member, The study shows that the Early Cretaceous magmatic diapirism was active in the study area, and magmatic diapirism had been developed in the Asan, As4 and Teng1 Member and sedimentary end of the Teng2 Member, leading to the occurrence of local tectonism During the deposition of the second member of the Tengsei Formation, in addition to tectonic inversion due to the development of magmatic diapirism, it also develops left-lateral compressive-torsional activity and leads to positive and negative inversion of structure.Therefore, two different genetic types were developed during the Early Cretaceous , Which is mainly related to the magmatic diapirism caused by subduction and anomalous mantle uplift of the Ezenacai plate in the Erlian Basin during the Early Cretaceous and the deposition of the Teng2 Member Qi Yi Zena subduction area change in direction caused by strike-slip effect is closely related.