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在对江汉平原江陵剖面全新世沉积物的沉积环境和年代学分析的基础上,利用由现代洪水沉积所建立的洪泛沉积物磁组构参数标志,对江汉平原全新世以来的古洪水事件进行了初步研究.结果表明:(1)江汉平原全新世以来(有史料记载前),共有55个特大洪水沉积层(事件).(2)全新世以来特大洪水(期)演化可分为两个大的阶段:第一阶段(9875～3000aBP)低频期,该阶段洪水发生频率不高,且洪水周期比较稳定,主要以近千年和500～625a周期为主;第二阶段(3000aBP～现在)为洪水频发期.洪水发生的周期以300～200a为主,反映出洪水发生的频率具有加快的趋势.
Based on the analysis of sedimentary environment and geochronology of the Holocene sediments in Jiangling section of Jianghan Plain, the flood events of flood sediments established by modern flood sedimentation are used to study the paleo-flood events since the Holocene in the Jianghan Plain (1) A total of 55 extra-large flood sediments (events) since the Holocene of the Jianghan Plain (before historical records). (2) The evolution of extra-large floods (periods) since the Holocene can be divided into two Large stage: the first stage (9875 ~ 3000aBP) low-frequency period, the flood occurred at this stage is not high frequency, and the flood cycle is relatively stable, mainly in the past millennia and 500 ~ 625a cycle-based; second phase (3000aBP ~ now) The period of flood occurs mainly in 300 ~ 200 years, which indicates that the frequency of flood is accelerating.