摘要
生物硅沉积记录可以反映海洋表层水体的古生产力。南海南部１７９６２柱状样３万余年来的生物硅堆积速率曲线表明，南沙海区古生产力的升高与一系列变冷事件，如冰期中的Ｈｅｉｎｒｉｃｈ事件、冰消期新仙女本事件、中晚全新世变冷事件等有良好的对应关系。冬季风的强化及由此导致的海洋古生产力的升高可能是上述良好对应关系的内在原因。
Biogenic silica is a good proxy for paleoproductivity of sea surface water. A high-resolution accumulation rate record of biogenic silica was obtained from core 17962 taken from the southern South China Sea (7°11'N, 112° 5'E), whose total length and history are 790 cm and ca. 34 000 a, respectively. The record shows that the accumulation rate of biogenic silica in the glaciation were much higher than that in the Holocene. Moreover, the rate in glaciation correlates well with δ^(18)O record in the GRIP ice core and obviously corresponds to the cool events such as Heinrich events and Younger Dryas. Beside, the frequent fluctuations of the rate during Heinrich events reveal that the Dansgaard/Oeschger events may exist in the region. In the southern South China Sea, the strong East Asian winter monsoon could decrease sea surface temperature largely, develop upwelling currents and destroy stratified water body. Consequently, the paleoproductivity raised, which indicated in the record of the accumulation rate of biogenic silica. This result is similar to that in the Chinese loess, where the grain-size maxima, which is indicators of strengthening of the East Asian winter monsoon, corresponded to Heinrich events very well. The transcontinental teleconnection between North Atlantic Ocean and East Asian supports that large scale of paleoclimate process controlled the Heinrich and D/O events.
出处
《地球化学》
CAS
CSCD
北大核心
2000年第3期293-296,共4页
Geochimica
基金
国家杰出青年基金!(49453004)
中国科学院百人计划资助
关键词
生物硅
古海洋学事件
南海
沉积记录
biogenic silica
paleoceanography events
South China Sea
