现在的学习从活塞核心 KCES1 基于 sedimentological 数据离开南部的 Ulleung 盆边缘,东方海(日本的海) 。数据包括沉积颜色(L *) , X 光检查拍,谷物尺寸分发和 AMS14C 日期。四种沉积(同类,把压成薄片,非常把压成薄片并且混合沉积) 根据被认为在底部水氧化反映变化的沉积结构的人物的意见被识别。黑暗 laminated/crudely 的引申把沉积和轻同类的沉积压成薄片代表可能在东方亚洲季风(电动会计记帐机) 与高分辨率的变化被联系的千年规模的变化。华东海沿海的水(ECSCW ) 和 Tsushima 的相对贡献温暖电流(TWC ) 是可能的为重复的主要原因缺氧并且自从最后 48 ka BP, oxic depositional 在东方海调节。在间冰段期间,因为更多的潮湿的气候, strengthen 夏天电动会计记帐机在中亚被归因于 ECSCW 的扩大,然后更强烈低咸度的、充实营养素的水被介绍进东方海。深水的通风被限制,因此,黑暗把在缺氧的底部水条件下面扔的层压成薄片。在在最后冰川的最大值(LGM ) 的海水平的最低看台期间,孤立的东方海由成层的水群众和形成的 euxinic depositional 环境统治了。自从显示 TWC 与海水平和底部水氧水平的逐步的上升逐渐地侵入了进东方海的 17.5 ka BP,同质的沉积一直在支配高。在晚更年轻的 Dryas (YD ) 时期期间,因为底部水的通风被更强壮的夏天电动会计记帐机限制,最后黑暗把扔的层压成薄片。加强的 TWC 和底部水从 10.5 ka BP 再成为了 oxic。
The present study is based on the sedimentological data from a piston core KCES1 off the southern Ulleung Basin margin,the East Sea(Sea of Japan).The data include sediment color(L^*),X-ray radiographs,grain size distribution and AMS^14C date.Four kinds of sediments(homogeneous,laminated,crudely laminated and hybrid sediments) are identified according to the characters of the sedimentary structures that were considered to reflect changes in bottom-water oxygenation.Alternations of dark laminated/crudely laminated sediments and light homogeneous sediments represent millennial-scale variations that are possibly associated with the high-resolution changes in the East Asian monsoon(EAM).The relative contributions of the East China Sea Coastal Water(ECSCW) and the Tsushima Warm Current(TWC) were likely the main reasons for the repetition of the anoxic and oxic depositional conditions in the East Sea since the last 48 ka BP.During the interstadial,the strengthen summer EAM was attributed to the expansion of the ECSCW because of more humid climate in central Asia,and then more strongly low-salinity,nutrient-enriched water was introduced into the East Sea.The ventilation of deep water was restricted and therefore the dark laminated layer deposited under the anoxic bottom water condition.During the lowest stand of sea level in the last glacial maximum(LGM),the isolated East Sea dominated by stratified water masses and the euxinic depositional environment formed.The homogenous sediments have been predominating since 17.5 ka BP indicating that the TWC has intruded into the East Sea gradually with the stepwise rise of sea level and the bottom water oxygen level was high.During the late Younger Dryas(YD) period,the last dark laminated layer deposited because the ventilation of bottom water was restricted by stronger summer EAM.The TWC strengthened and the bottom water became oxic again from 10.5 ka BP.