晚中生代地球表层重大地质事件的陆地环境剧变与生物群演替响应

The biotic and environmental response to the geological events on the Earth during the Late Mesozoic

晚中生代时期华北东北部发育燕辽生物群、热河生物群和阜新生物群陆地生物群。它们的快速演变过程和华北克拉通上同时期发育的岩石圈减薄、大面积强烈岩浆活动、变质核杂岩及伴随的伸展盆地等地球表层重大地质事件并行发生,表现着地壳表层系统圈层间的相互作用和响应。生物群的繁盛与灭绝与地球表层大规模岩浆-火山活动(髫髻山组—张家口组和大北沟组—义县组)发育时代高度协同一致。地球表层重大地质事件直接或间接地控制或改造着地球表层古地理和古生态环境,生物群只得调整自身去适应环境和生态背景的改变。火山-岩浆活动改变着地质-生态环境,生物群都紧密联系多期次火山-岩浆活动,化石也都被埋葬在沉积-火山碎屑岩中。华北克拉通破坏重大地质事件发生响应于全球变化和统一地球表层系统。盆地沉积充填序列、特殊陆相环境沉积建造、特殊环境沉积物等记录了响应的古地理、古环境变化与响应。陆地生物群分布、演化、更替与精确定年,脊椎-无脊椎生物(化石)埋葬特征,生物演化速率、消长关系和生物群(组合)更替的形式和性质,以及脊椎动物骨骼、牙齿的常量、微量元素、H-B-C-N-O-S和C-O-Sr等地球化学特征的研究可以恢复和重建古地理、古生态环境和古生态系统。

Three terrestrial biotas,i.e.,the Yanliao,Jehol and Fuxin biotas,existed around the North China during the Late Mesozoic.Evolutionary radiation of the biotas accompanied with a series of geological events,such as lithospheric thinning,magmatic activities,metamorphic core complex and extensional basins,which suggests a mechanism of interaction and response in the Earth surface systems.Radiation and extinction of the biotas were highly coincident with large igneous provinces（Tiaojishan Fm.-Zhangjiakou Fm.and Dabeigou Fm.-Yixian Fm.） in geochronological perspectives.Ecosystems and palaeogeography of the Earth surface system were strongly,directly or indirectly,affected or reformed by those contemporaneous geological events,and for surviving the biotas had to change themselves and to radiate to adapt the affected ecosystems or palaeogeography.Ecosystems or evolutionary radiation was also affected by volcanic eruptions and magmatic activities.The biota（fossils） are mostly preserved in lacus 多trine deposits bearing a number of volcanic tuffs or interclations of lavas,which provide a window for understanding the interaction and response.A remarkable geological event and a response to global Earth surface system,i.e.,the North China Craton-breaking-up,occurred during the Late Mesozoic,which was recorded within the contemporaneous sedimentary successions and a series of characterized terrestrial deposits.Synthesized researches on biotic evolution,alternation and accurate chronological dating,taphonomy of vertebrate or invertebrate fossils and elemental or isotopic geochemistry of bones of fossils and sediments,i.e.,H-B-C-N-O-S and C-O-Sr,could help us to well understand the biotic and environmental response to the geological events on the Earth surface system and reconstructed the palaeogeography,palaeoecologic environment and palaeoecosystem of the Late Mesozoic,North China.