Study Of Magnetostratigraphy At Cangfang Bisec And Climatic Environmental Indicators In Xichuan County Of Henan Province

Cangfang bisect at Cangfang town,Henan province is a series of strata-occurrence stability and Continuous fluviolacustrine sediments,we built High-resolution magnetostratigraphy framework by studying section lithology,fossils and 453 paleomagnetic samples.The age of Cangfang section is from 40-37Ma.To systematic study the paleoenvironment characteristic of studying section,We measured the the physical index such as magnetic susceptibility,chromaticity,density,particle size to show the paleoclimatic characteristics of the Xijiadian section,rebuilt the paleoclimatic change process of 57-37Ma in this section,and lay a solid foundation for Xijiadian future research.The evolution of the paleoenvironment of the Xijiadian section can be divided into the following sections:?(37-39.5MaBP,Depth of 0-147.5m)Reflecting the cold climate during the early Eocene,more rain,low lake water level,strong hydrodynamic,Antarctic ice sheet formation period.?(39.5-43MaBP,Depth of 147.5-361m)Warm and humid climate,lake surface is higher and stable,weak hydrodynamic conditions,corresponding to MECO climate events.?(43-50.7MaBP,Depth of 361-842m)The climate is warm and humid,lasting longer,the equivalent of EECO events.iv(50.7-57MaBP,Depth of 842-1189m)The climate is generally warm and wet,but unstable,it is a fluctuating climate and there are several climatic events ETM3,ETM2 and PETM extreme events,which can be divided into two sub-sections.Deep-sea oxygen isotope data show that the global climate since 57-37Ma has been consistent with the physical index.Global climate events,such as PETM,MECO,C19r events,are well reflected of the Xijiadian section.Through the comparison of regional and global climate changes,we try to analyzes the causes and driving mechanism of climate change of Xijiadian section.