南海深水区晚更新世以来沉积速率、沉积通量与物质组成  

Constituents of Matter and Sedimentation Fluxes and Sedimentation Rates of Deep-water Sedimentation during the Late Pleistocene in the South China Sea

作　　者：章伟艳[1] 张富元[1] 陈荣华[1] 张霄宇[2] 

机构地区：[1]国家海洋局第二海洋研究所,国家海洋局海底科学重点实验室,杭州310012 [2]浙江大学地球科学系,杭州310012

出　　处：《沉积学报》2002年第4期668-674,共7页Acta Sedimentologica Sinica

基　　金："九五"国家专项重大资助项目;国家海洋局青年海洋科学基金资助项目 (批准号 :2 0 0 1 51 0 )

摘　　要：通过调查所获得柱样沉积物氧碳同位素测年资料及多学科综合分析表明 ,晚更新世以来南海沉积速率和沉积通量具有以下几个特征 :(1)总体上为间冰期沉积速率低、冰期沉积速率高 ,冰期沉积速率是间冰期沉积速率的 1.3～ 1.6倍 ;(2 )南海沉积速率趋势面分析表明 ,氧同位素 1期东北陆坡和西南陆坡沉积速率高 ,氧同位素 2、3期沉积速率分布特征相似 ,与 1期有所不同 ,东北陆坡沉积速率高于西南陆坡 ,表明氧同位素 2期之后 ,南海的沉积环境发生明显的改变 ,造成上述沉积速率分布的主要控制因素是南海周围的河流分布、季风、海流等 ;(3)南海东部沉积通量与物质组成分析表明 ,末次冰期以来沉积总通量北部陆坡区明显高于深海区 ,前者是后者 2～ 3倍 ,并有自北向南逐渐降低的趋势 ;(4)硅质生物沉积通量冰期明显高于间冰期 ,末次冰期以来东北部陆坡区的硅质生物沉积通量最高 ,末次冰期之前恰好相反 ,深海盆高于陆坡区 ;(5 )末次冰期以来 ,陆源沉积约占南海东部海域沉积的 4 4Based on the integrated study of sediment cores in the South China Sea, the sedimentation rates feature during the Late Pleistocene has been shown.(1) On the whole, the rates of glacial stages is 1.3～1.6 times for the interglacials.(2)Trend analysis on the sedimentation rate is performed, which indicates that the rates of cores during δ 18 O Stage 1 were high in the northeastern and south western continental slope. The features resulted from trend analysis were the main controlling factors of the river distribution, monsoon and ocean current etc. The sedimentation rates of cores during δ 18 O Stage 2 and 3 were similar, which were different from that of during δ 18 O Stage 1, only that were high on the northeastern continental slope. So the sediment environment in the South China Sea was significantly modified after the δ 18 O Stage 2. Based on the study of sediment cores in the Eastern South China Sea, the constituents of the main matter and sedimentation fluxes feature were obtained.(1)From the last glacial stage, the sedimentation fluxes on the northern continental slope were higher than that of the deep basin.(2) The sedimentation fluxes of silicon organic substances during the glacial stage were higher than that of the interglacials.(3)From the last glacial stage, the terrigenous constituents were 44% above in the abyssal plains sediments.

关 键 词：南海 晚更新世 沉积通量 沉积速率 碳同位素 氧同位素 

分 类 号：P736.21[天文地球—海洋地质]