中国东北部中生代孢粉组合序列及古气候演变

MESOZOIC SPORO-POLLEN ASSEMBLAGES AND CLIMATE FLUCTUATIONS IN NORTHEAST CHINA

东北地区是中国境内中生界发育较完整的地区之一,其中三叠系在内蒙古二连盆地东北部发育较好,侏罗系发育较完整的剖面分布于冀北、辽西及二连盆地,下白垩统以二连盆地和辽西地区发育齐全且研究程度较高,上白垩统以松辽盆地发育最佳,研究程度最高。以东北地区中生界作为研究载体,对中生代孢粉化石群加以清理,共整理出29个孢粉化石组合。经研究认为,东北地区中生代古气候背景经历了2个超级周期、4个一级周期,以及12个二级气候变化周期。

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 2 super-cycles, 4 first- level cycles, and 12 secondly-level cycles in the Mesozoic of Northeast China.