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对东海近岸泥质区16孔与31孔岩心进行了测年和粒度分析,并对其影响因素及所指示的沉积环境变化进行了探讨。结果表明,16孔与31孔岩心的沉积年代分别为49年(1954—2003年)和181年(1822—2003年),平均沉积速率分别是3.27和0.82cm/a。根据两孔岩心粒度特征,经讨论分析,认为16孔岩心粒度变化主要受长江来沙变化和长江入海主泓位置变化的影响;自1900年之后,31孔岩心粒度变化在一定程度上反映了东亚季风强度的变化。另外,两个岩心中风暴潮和洪水沉积记录与历史资料吻合很好,有利于灾害性事件的研究。
The dating and grain size analysis of 16 and 31 holes in the muddy area near the coast of the East China Sea were carried out. The influencing factors and the changes of sedimentary environment were also discussed. The results show that the sedimentary age of 16-well and 31-well cores are 49 years (1954-2003) and 181 years (1822-2003), respectively. The average deposition rates are 3.27 and 0.82 cm / a respectively. According to the characteristics of grain size of two holes, after discussion and analysis, it is considered that the variation of grain size of 16-hole core is mainly affected by the change of sediment in the Yangtze River and the change of the location of the main stream in the Yangtze River. After 1900, the grain size of 31 holes reflects to some extent the East Asia Monsoon intensity changes. In addition, records of stroke and flood sedimentation in both cores coincide well with historical data, which is good for the study of catastrophic events.