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文章讨论了南黄海泥质区、东海陆架及冲绳海槽北部表层沉积物和柱状岩芯中10Be及9Be含量的水平和垂直分布,并与重金属Pb的分布进行了比较。表层沉积物中的10Be,9Be和Pb三者表现出完全不同的分布特征。10Be的分布主要受黑潮及其支流黄海暖流所支配;9Be的分布受黄河陆源物质输入的影响,主要集中在南黄海泥质区;Pb则主要分布在长江口和琉球群岛附近,反映了人类活动的影响。冲绳海槽北部末次冰期和全新世时10Be的沉积通量变化在整体上反映了10Be大气生产率的变化,即地球磁场屏蔽效应的影响。03孔全新世时10Be的沉积通量(1·12×109atoms/cm2ka)基本上等于10Be的现代大气平均生产率,而在末次冰期时平均为4·06×109atoms/cm2ka,高于10Be的现代大气平均生产率3倍以上。在冲绳海槽由于黑潮的缘故,10Be对气候的变化响应要比极地冰芯的10Be变化响应灵敏的多,对气候变化信号起了放大的作用。冰期时冲绳海槽北部10Be的沉积通量远远高于太平洋大洋海区,充分反映了黑潮的传送带作用和边缘海的聚焦沉积作用,并表明末次冰期时在千年尺度上黑潮仍流经冲绳海槽,且强度并未减弱。10Be的通量在新仙女木时降到整个岩芯所跨时期的最低点,甚至低于10Be的现代大气平均生产率,因此推测在新仙女木事件时,黑潮的变动特别大,有可能改向或断流。
The horizontal and vertical distributions of 10Be and 9Be in surface sediments and columnar cores in the northern part of the Yellow Sea, the East China Sea shelf and the northern Okinawa Trough are discussed in this paper. The distributions of Pb and Pb in heavy metals are also discussed. 10Be, 9Be and Pb in the surface sediments showed completely different distribution characteristics. The distribution of 10Be is dominated by the Kuroshio and its tributaries, the Yellow Sea warm current. The distribution of 9Be is mainly affected by the import of the Yellow River terrestrial materials, mainly in the southern Yellow Sea muddy area. Pb is mainly distributed in the vicinity of the Yangtze River estuary and the Ryukyu Islands, Impact of activities. The changes of 10Be flux in the northern part of the Okinawa Trough during the last glacial period and the Holocene reflect the change of 10Be atmospheric productivity as a whole, that is, the influence of the Earth’s magnetic field shielding effect. In the Holocene, the deposition flux of 10Be (1 · 12 × 109 atoms / cm 2 ka) is basically equal to the average productivity of 10Be in modern times, and averaged 4.6 × 109 atoms / cm 2 ka in the last glacial period, higher than that of 10Be Average productivity more than 3 times. Due to the Kuroshio in the Okinawa Trough, 10Be responded more sensitively to changes in climate than the 10Be changes in polar ice cores, amplifying the climate change signal. During the glacial period, the 10Be flux in the northern part of the Okinawa Trough is much higher than that in the Pacific Ocean, which fully reflects the role of the Kuroshio belt and the focal sedimentation of the marginal sea. It also indicates that the Kuroshio current flows through Okinawa Trough, and strength has not diminished. The flux of 10Be dropped to the lowest point in the span of the entire core or even lower than the average productivity of 10Be at the time of the new fairy wood. Therefore, it is speculated that the change of the Kuroshio in the new fairy wood event is particularly large and may change To or cut off.