Coccolith Assemblages and Primary Productivity Variations in the Central Western Pacific Warm Pool Over the Last 380 kyr  

作　　者：LIANG Dan LIU Chuanlian 

机构地区：[1]State Key Laboratory of Marine Geology, Tongji University [2]Library, Tongji University

出　　处：《Journal of Ocean University of China》2018年第3期563-570,共8页中国海洋大学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Nos. 41376047, 91428310, 91228204)

摘　　要：Coccolith assemblages in two gravity cores(KX21-2 and KX12-1) from the central Western Pacific Warm Pool(WPWP) have been analyzed with SYRACO. The variations of nutricline and primary productivity(PP) have been reconstructed based on these assemblages. The results show that the coccolith assemblages were dominated by Florisphaera profunda, Gephyrocapsa and Emiliania huxleyi over the last 380 kyr. Variations of nutricline and primary productivity can be divided into three intervals. Interval I(about 380–300 kyr): PP was high and nutricline was shallow; Interval II(about 300–160 kyr): PP decreased dramatically for a short time after the acme of G. caribbeanica in Mid-Brunhes while nutricline became deeper; Interval III(about 160 kyr–present): PP fluctuated at low levels and nutricline was deep. Variations of each coccolith taxon and PP were highly correlated in the two cores, which means that the geological environment is similar in the two cores. Spectrum analysis is performed for all coccolith taxons and PP, and the 19-kyr cycle is the most prominent. It means that the production of coccolithophores in the WPWP is mainly controlled by precession.Coccolith assemblages in two gravity cores （KX21-2 and KX12-1） from the central Western Pacific Warm Pool （WPWP） have been analyzed with SYRACO. The variations of nutricline and primary productivity （PP） have been reconstructed based on these assemblages. The results show that the coccolith assemblages were dominated by Florisphaera profunda, Gephyrocapsa and Emiliania huxleyi over the last 380 kyr. Variations of nutricline and primary productivity can be divided into three intervals. Interval I （about 380–300 kyr）： PP was high and nutricline was shallow; Interval II （about 300–160 kyr）： PP decreased dramatically for a short time after the acme of G. caribbeanica in Mid-Brunhes while nutricline became deeper; Interval III （about 160 kyr–present）： PP fluc-tuated at low levels and nutricline was deep. Variations of each coccolith taxon and PP were highly correlated in the two cores, which means that the geological environment is similar in the two cores. Spectrum analysis is performed for all coccolith taxons and PP, and the 19-kyr cycle is the most prominent. It means that the production of coccolithophores in the WPWP is mainly controlled by precession.

关 键 词：coccolith assemblage Western Pacific Warm Pool primary productivity nutricline PRECESSION 

分 类 号：P73[天文地球—海洋科学]