Stepwise paleoceanographic changes during the lastdeglaciation in the southern South China Sea: Records of stable isotope and microfossils  

作　　者：翦知湣 陈民本 林慧玲 汪品先 

出　　处：《Science China Earth Sciences》1998年第2期187-194,共8页中国科学（地球科学英文版）

基　　金：theNationalNaturalScienceFoundationofChina (GrantNos.495 76 2 86and 49732 0 86 )

摘　　要：Quantitative analyses of microfossils and stable isotopic analysis were carried out for Core SCS-12 in the southwestern slope of the South China Sea (SCS). A high-resolution paleoceanographic record for the last 13 ka was revealed with the AMS 14 C dates. The southern SCS has experienced stepwise paleoceanographic changes since the last deglaciation. The oxygen isotopic stage 1/2 boundary around 12.05 ka B.P. and the end of the last deglaciation around 7.70 ka B.P. are two rapid change periods (corresponding to the termination I\-A and termination I\-B, respectively), in between is a slow change period. The authors infer that the sea level stood at -110 m before the termination I\-A, roughly the same as today after the termination I\-B, and about -50 m in between. Subsequently, the average winter sea surface temperature and salinity obviously increased while paleo-productivity decreased since 12.05 ka B.P. The early Holocene CaCO\-3 preservation spike, coupled with a high abundance of pteropoda and CaCO\-3 content, occurred around 7.70 ka B.P.Quantitative analyses of microfossils and stable isotopic analysis were carried out for Core SCS-12 in the southwestern slope of the South China Sea (SCS). A high-resolution paleoceanographic record for the last 13 ka was revealed with the AMS14C dates. The southern SCS has experienced stepwise paleoceanographic changes since the last deglaciation. The oxygen isotopic stage 1/2 boundary around 12.05 ka B. P. and the end of the last deglaciation around 7.70 ka B.P. are two rapid change periods (corresponding to the terminationIa and terminationIb, respectively), in between is a slow change period. The authors infer that the sea level stood at - 110 m before the terminationIa, roughly the same as today after the termination IB, and about - 50 m in between. Subsequently, the average winter sea surface temperature and salinity obviously increased while paleo-productivity decreased since 12.05 ka B.P. The early Holocene CaCO3 preservation spike, coupled with a high abundance of pteropoda and CaCO3 content, occurred around 7.70 ka B. P.

关 键 词：LAST DEGLACIATION STEPWISE change stable ISOTOPE MICROFOSSILS South China Sea. 

分 类 号：P736.2[天文地球—海洋地质]