摘要
通过对位于东海内陆架泥质区中部的MZ02孔进行粒度和生物硅分析,AMS14C测年,获得了粒度和生物硅随时间变化的高分辨率曲线。结果表明,近2 ka以来研究区沉积环境稳定,以沿岸流控制的浅海沉积为主;沉积物中生物硅含量<1.5%,属于低含量海区,主要受低硅质骨骼供给量、高溶解作用以及陆源物质冲淡作用的影响。生物硅含量及其堆积速率与中国东部温度曲线对比显示,近2 ka以来生物硅含量及其堆积速率在相对高温期明显增加,而在相对低温期降低,反映了表层生产力对气候变化的响应,其高值期可能是由于相对高温期夏季风的加强导致了上升流的增强和营养物质供给的增加。另外,MZ02孔生物硅含量及其堆积速率与格陵兰冰芯和红原泥炭同位素对应性较好,揭示了古生产力和古气候变化的区域性以至全球性联系。
High-resolution grain size,biogenic silica and its mass accumulation rate（MAR） records are gained by AMS14C dating and analyses of grain size and biogenic silica in Core MZ02 from the muddy area on the inner shelf of the East China Sea.The grain size results reflect a low-energy shallow sea shelf depositional environment dominated by the coastal currents.The biogenic silica content in Core MZ02 is less than 1.5%,mainly controlled by the low supply of biogenic silica remains,high silica dissolution and terrigenous matter dilution.Comparing the biogenic silica content and its MAR with the climatic record inferred from the Eastern China mainland,the relatively high biogenic silica and its MAR generally concur with the warm and humid climatic intervals,and vice versa,suggesting the response of the biogenic silica to paleoclimatic variation of Eastern China.The high paleoproductivity indicated by biogenic silica and its MAR was induced by the intensified Asian summer monsoon,which could strengthen the upwelling and increase the supply of nutrition materials.In addition,the biogenic silica and its MAR correlated well with the δ18O records of GISP2 ice core and Hongyuan peat,which therefore revealed a regional response of biogenic silica to global climate change.
出处
《沉积学报》
CAS
CSCD
北大核心
2011年第2期321-327,共7页
Acta Sedimentologica Sinica
基金
我国近海海洋综合调查与评价专项(编号:908-ZC-I-05和908-02-02-05)
海洋公益性行业专项(编号:200805063)
国家自然科学基金重点项目(批准号:40431002)资助
关键词
生物硅
古生产力
古气候
2ka以来
泥质区
东海内陆架
biogenic silica
paleoproductivity
paleoclimate
2ka BP
muddy area
inner shelf of the East China Sea
