华北早白垩世古地貌动态演变及热河生物群东迁  

Early Cretaceous dynamic evolution of paleo-landscape and eastward migration of Jehol Biota in North China

作　　者：宋双双 索艳慧[1,2] 李三忠 丁雪松[3] 韩续 田子晗 付新建 SONG Shuangshuang;SUO Yanhui;LI Sanzhong;DING Xuesong;HAN Xu;TIAN Zihan;FU Xinjian(Frontiers Science Center for Deep Ocean Multispheres and Earth System,Key Lab of Submarine Geosciences and Prospecting Techniques,MOE and College of Marine Geosciences,Ocean University of China,Shandong Qingdao 266100,China;Laboratory for Marine Mineral Resources,Laoshan Laboratory,Shandong Qingdao 266237,China;University of California Los Angeles,Department of Earth,Planetary and Space Sciences,Los Angeles CA90095,USA)

机构地区：[1]深海圈层与地球系统教育部前沿科学中心,海底科学与探测技术教育部重点实验室,中国海洋大学海洋地球科学学院,山东青岛266100 [2]崂山实验室海洋矿产资源评价与探测技术功能实验室,山东青岛266237 [3]加州大学洛杉矶分校地球行星与空间科学学院,美国加州洛杉矶CA90095

出　　处：《古地理学报》2024年第1期172-191,共20页Journal of Palaeogeography：Chinese Edition

基　　金：崂山实验室科技创新项目(编号:LSKJ202204400);国家自然科学基金项目(编号:42121005,91958214);山东省自然科学基金项目(编号:ZR2021ZD09,ZR2021YQ25);中央高校基本科研业务费专项(编号:202172003)联合资助。

摘　　要：早白垩世期间,华北地区东北部分布着极其重要的生物群——热河生物群,其繁盛期对应着华北克拉通破坏峰值时期(125 Ma)。华北克拉通破坏导致的古地貌和古气候等环境变化,可能是引起热河生物群分布时空发生变迁的重要外部驱动因素之一。然而,目前缺少对华北地区早白垩世古地貌动态演变过程的定量描述。因此,本研究主要通过构建古土壤风化指标(PWI、CFX_(Na))、碳酸盐同位素等数据库,重建了华北地区晚侏罗世—早白垩世之交(145 Ma)的古地形;并结合磷灰石/锆石裂变径迹、剥蚀厚度恢复、海平面变化等数据,利用Badlands软件定量化动态模拟了华北地区早白垩世古地貌演变过程。模拟结果表明,早白垩世期间,受控于古太平洋板块俯冲后撤的影响,华北克拉通经历了由“东高西低”变为“西高东低”的地形翘变和破坏过程,并伴随着自西向东的断陷盆地的迁移;大规模火山喷发与断陷盆地的出现共同控制了热河生物群的向东迁移,热河生物群在燕山地区的山间盆地兴起。It is suggested that the spatio-temporal evolution of the Jehol Biota in northeastern North China is driven by the North China Craton destruction during the Early Cretaceous,due to the abrupt changes in paleogeographic environment.However,little quantitative work on the dynamic paleo-landscape evolution in North China has been done.In this study,we employed paleosoil weathering indices(PWI and CFX_(Na))and carbonate isotopes to reconstruct the paleo-elevation of North China around 145 ma.We then integrated factors such as tectonic movements,sedimentology,paleoclimate,and sea level changes using the Badlands software to model the Early Cretaceous paleo-landscape evolution of North China.Our findings reveal that the eastern North China experienced an abrupt geomorphological transition from the collapse of a paleo-plateau to the formation of the Bohai Bay Basin due to the subduction retreat of the paleo-Pacific Plate.The geomorphological transitions led to the formation of a series of eastward-migrating rifted basins,including several newly-formed isolated intermountain basins in the Yanshan area where the Jehol Biota first emerged.Frequent volcanic activity provides rich nutrients for the lakes,and the paleoclimate turns to warm and humid gradually,which provide favorable conditions for the prosperity of the Jehol Biota.The eastward migrating subsidence basin,eruption of volcanoes and suitable paleoclimate jointly controlled the eastward migration of the Jehol Biota.

关 键 词：华北克拉通 早白垩世古地貌 热河生物群 断陷盆地 

分 类 号：P531[天文地球—古生物学与地层学]