THE GLOBAL WARMING PROCESS AND TERRESTRIAL BIOTA RESPONSE DURING EARLY TO MIDDLE CRETACEOUS PERIOD(LATE VALANGINIAN-EARLY TURONIAN)
The Cretaceous is a typical greenhouse world.The climate of the Cretaceous Period can be divided into three periods:warming,hot,and cooling.Among them,a long global warming process occurred during the Early to Middle Cretaceous(late Valanginian to early Turonian,135～92 Ma).Simultaneous with global warming,terrestrial organisms and ecosystems underwent rapid evolution and radiation.However,the warming process during the Early to Middle Cretaceous,especially the temperature records of the non-marine Cretaceous and the response of terrestrial biota,is still not well understood.Based on a summary of marine and non-marine temperature records,as well as terrestrial fossil records,the global warming process and the response of terrestrial biology during the Early to Middle Cretaceous period were investigated in this study.The published marine Cretaceous temperature data indicate that global temperatures gradually increased from the late Valanginian to the Barremian Stages,reaching the peak during earliest Aptian,with SST of＞32℃;and then,there was a decline of temperature during the middle and late Aptian stage,followed by further increase since Albian,reaching the maximum during the late Cenomanian-early Turonian stage,with SST of＞37 ℃.The temperature records of the non-marine Cretaceous imply a lower temperature during the late Valanginian to early Barremian,followed by a gradual increase from the Aptian to the Turonian.Terrestrial biota was widely distributed during the Valanginian to early Albian but decreased during the late Albian to Turonian as the global sea level increased.NE China developed well-preserved terrestrial biota during the Early to Middle Cretaceous,including the Jehol Biota,Fuxin Biota(Yanji Biota),and Songhuajiang Biota.The distribution and development of global terrestrial biota are closely related to the progress of warming during the Early to Middle Cretaceous Period.With a gradual increase in temperature,terrestrial biota,such as angiosperms and birds,radiated rapidly.Modern terrestrial ecosystems formed gradually during this period,evolving from Mesozoic to modern ecosystems.Our study indicates that the increase in temperature played an important role in the radiation evolution of the early to mid-stage Jehol Biota during the late Valanginian to Barremian.
万方数据
维普
