摘要
Mesozoic strata are well-developed in Northeast China.Among them,Triassic System is only found in the northeastern Errian Basin,Inner Mongolia;Jurassic System is fully developed in North Hebei,West Liaoning,and the Errian Basin;Lower Cretaceous strata are widely distributed in Northeast China,especially in the Errian Basin and West Liaoning;Upper Cretaceous strata are fully developed in the Songliao Basin.Based on sporopollen data,29 sporopollen assemblages were revised.It is revealed that the palaeoclimate changes recorded 2super-cycles,4firstlevel cycles,and 12secondly-level cycles in the Mesozoic of Northeast China.