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对取自南黄海中部泥质区YE-2钻孔的6.1m岩心进行了年代学、沉积学、微体古生物学和U3K7′海表温度分析,结果显示,该孔沉积物基本类型为黏土质粉砂,8400aBP来的沉积环境可分为3段:8.4～6.9kaBP为砂含量达13%的滨岸浅水环境;6.9～6.1kaBP为砂含量8%的滨岸浅水向稳定浅海过渡的环境;6.1～0kaBP为基本不含砂的黏土质粉砂稳定浅海环境。表层海水温度(SST)在滨岸浅水阶段较低,平均约14.2℃;在第2阶段从6.9kaBP开始增加,最高达18.1℃,指示了黄海暖流的入侵;6.4kaBP增温结束后,浅海阶段SST稳定在15～16℃之间,同时有3个SST平均为13.9℃的短暂低温期,大致为5.7～5.2、3.7～3.2和2.3～1.8kaBP。在稳定浅海环境的黏土质粉砂地层中发现了罕见的3个砂质粉砂质粗粒级夹层,大致形成于6.0、3.9和2.5kaBP,其粒度具有风暴沉积特征,重矿物表现出变质岩特点,U3K7′-SST和黏土矿物指示其沉积环境的温度偏高。上述特征与岩心其他所有层位差异较大,显示了异地搬运的特征,可能为风暴沉积。根据AMS14C测年,不考虑风暴沉积,YE-2岩心的沉积速率在50.7～75.6cm/ka之间。
The chronology, sedimentology, paleontology and U3K7 ’sea surface temperature analysis of the 6.1m core collected from the YE-2 borehole in the muddy area in the central part of the southern Yellow Sea show that the basic types of sediment in this hole are clay Silt, 8400aBP sedimentary environment can be divided into three sections: 8.4 ~ 6.9kaBP sand content of up to 13% of the coastal shallow water environment; 6.9 ~ 6.1kaBP sand content of 8% of the shallow coastal waters to stabilize the shallow sea transition environment; 6.1 ~ 0kaBP as the basic non-sandy clay sand silt stable shallow sea environment. The surface sea water temperature (SST) is relatively low at the shallow coastal water level, averaging about 14.2 ℃. In the second phase, the SST increases from 6.9kaBP to 18.1 ℃, indicating the invasion of the Yellow Sea warm current. After the 6.4kaBP warming, SST was stable between 15 and 16 ℃, and there were three short-term low-temperature periods with an average SST of 13.9 ℃, ranging from 5.7 to 5.2, 3.7 to 3.2 and 2.3 to 1.8kaBP. Three rare sandy silt coarse-grained interbeds were found in the clay-silt formations in a stable, shallow-sea environment, forming roughly at 6.0, 3.9 and 2.5 kaBP with grain size characterized by storm deposits and heavy minerals showing metamorphic rocks Features, U3K7’-SST and clay minerals indicate that their sedimentary environment is warmer. The above characteristics are quite different from all the other core layers and show the characteristics of handling in different places, which may be storm deposits. According to the AMS14C dating, the sedimentation rate of YE-2 core ranges from 50.7 to 75.6 cm / ka irrespective of storm deposits.