Paleoenvironmental Changes in the Northern Okinawa Trough since 25 ka BP:REE and Organic Carbon Evidence  

作　　者：徐兆凯 李铁刚 南青云 于心科 李安春 Jinyong Choi 

机构地区：[1]Key Laboratory of Marine Geology and Environment,Institute of Oceanology,Chinese Academy of Sciences [2]Department of Oceanography,Kunsan National University,Kunsan 573-701,Korea

出　　处：《Journal of Earth Science》2012年第3期297-310,共14页地球科学学刊（英文版）

基　　金：supported by the Open Fund of the Key Laboratory of Marine Geology and Environment,Chinese Academy of Sciences,the Innovative Program of Chinese Academy of Sciences(No.KZCX2-YW-221);the National Basic Research Program of China(No.2007CB815903);the National Natural Science Foundation of China(Nos. 41106043 and 40906038)

摘　　要：Paleoenvironmental changes in the northern Okinawa trough covering the last 25 ka were synthetically reconstructed using REE and organic carbon indices of core CSH1.Variations of these parameters revealed three distinct intervals of major sediment provenance changes that can be related to sea-level fluctuation and Tsushima Warm Current evolution.Interval 1（16-24.7 ka BP） is characterized by dominantly fluvial discharge from the Changjiang（Yangtze River） and Huanghe（Yellow River） as well as high primary productivity.In Interval 2（7.3-16 ka BP）,the Changjiang and Huanghe mouths regressed with sea-level rising.The newly formed Tsushima Warm Current could carry some sediment loads of Taiwan to the study core,especially during its late phase（7.3-8.2 ka BP）.Modern oceanographic conditions were finally established since the beginning of Interval 3,leading to more terrigenous contribution from Taiwan,whereas low sea-surface productivity in the study area.Paleoenvironmental changes in the northern Okinawa trough covering the last 25 ka were synthetically reconstructed using REE and organic carbon indices of core CSH1.Variations of these parameters revealed three distinct intervals of major sediment provenance changes that can be related to sea-level fluctuation and Tsushima Warm Current evolution.Interval 1（16-24.7 ka BP） is characterized by dominantly fluvial discharge from the Changjiang（Yangtze River） and Huanghe（Yellow River） as well as high primary productivity.In Interval 2（7.3-16 ka BP）,the Changjiang and Huanghe mouths regressed with sea-level rising.The newly formed Tsushima Warm Current could carry some sediment loads of Taiwan to the study core,especially during its late phase（7.3-8.2 ka BP）.Modern oceanographic conditions were finally established since the beginning of Interval 3,leading to more terrigenous contribution from Taiwan,whereas low sea-surface productivity in the study area.

关 键 词：paleoenvironmental change the northern Okinawa trough Tsushima Warm Current REE discriminant function. 

分 类 号：P595[天文地球—地球化学]