Sedimentary Record , Provenances And Paleoenvironment Significance Of S06-2 Columnar Samples In The East China Sea From 27.5ka B.P.

In this paper,we analyzed the Sedimentary characteristics,provenance and paleoclimate evolution of sediments of the S06-2 columnare core which in the inner shelf mud area of the southern part of the East China Sea since 27.5ka.through AMS¹⁴C dating data,grain size,mineral characteristics of clay and XRF Element analysis and Paleoclimate Inversion with the comparision of previous research results and major historical events in the corresponding research areas.The particle size component takes the powder sand as the main component,followed by the clay,the sand content is the least,the deposition rate is large,the sorting is poor.The characteristics of clay mineral components and the results of dating years show that S06-2 sediment columnar samples are basically all affected by the rivers in eastern Taiwan,and the influence of the Yangtze River material in different periods is different and gradually increased from old to new.Almost all of the sediment debris from the 27.5-20.5ka is shown in Taiwan's rivers and is mainly a river in eastern Taiwan,with a small source of material from the Yellow River.During 20.5-10.6ka,the debris is dominated by river of eastern Taiwan and the weak influence come from Yangtze River material,the main source of10.6ka-5.5ka is the river debris in eastern Taiwan,and the Yangtze River clastic material is added;5.5ka so far,the southern part of Taiwan's River launches inland frame continues to transport a large number of sources,the Yangtze River and The Yellow River debris have a mixed effect.Based on the ratio of core sensitive particle size components,selecting Rb/Sr,Zr/Rb,Montmorillonite/kaolinite as indicators,9 cooling events were identified by comparing the records of oxygen isotopes of Antarctic ice cores and Gurria ice cores:26800a Bp,24000a BP,21800 a Bp,18600a Bp,15500a BP,10800 a BP,8300 a BP,6000a BP,3800a BP,corresponding to global cold events.Monsoon evolution is divided into 3 stages:27500-19100ka BP East China Sea Inland frame winter wind strength is unstable,continuous fluctuation;19100-8200a BP,East Yadong Monsoon first weakened,later enhanced,volatile;8200a BP so far,East Asian winter wind is relatively weak,and the impact on sediment gradually weakened.