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文章讨论了末次冰期及全新世以来冲绳海槽中部偏东处的沉积物岩芯Z14-6中~(10)Be的历史记录,并与冲绳海槽北部钻孔DGKS9603的~(10)Be记录进行对比。重力柱状岩芯Z14-6取于冲绳海槽水下739m(27°07′N,127°27′E),全长8.96m。选取了晚更新世末次冰期和全新世的层段(2～175cm,年代跨度为0.37～29.3kaB.P.)中12个层位,利用加速器质谱法测定了~(10)Be的含量。Z14-6孔~(10)Be的平均含量为6.10×10~8 atoms/g,最高值(8.71×10~8atoms/g)出现在6.3kaB.P.层位,末次冰期~(10)Be含量总体上处于低值。与DGKS9603孔(28°08.869′N,127°16.238′E;水深1100m,岩芯长585cm)的数据比较,Z14-6孔中~(10)Be含量普遍较低。Z14-6孔的~(10)Be沉积通量平均值为1.04×10~9 atoms/cm~2·ka,最高值(1.36×10~9 atoms/cm~2·ka)出现在6.3kaB.P.层位,最低值(6.45×10~8 atoms/cm~2·ka)出现在9.27kaB.P.层位。Z14-6孔所处水深较浅,黑潮流在末次冰期时并未流经Z14-6孔海区,所以其~(10)Be沉积通量只相当于~(10)Be的大气平均生产率(1.21×10~9 atoms/cm~2·ka)。Z14-6孔中~(10)Be沉积通量降低可能与几个低温事件有关,Z14-6孔在约3kaB.P.和9kaB.P.存在~(10)Be通量减弱现象,因此推测黑潮产生较大变动。Z14-6孔在全新世一些时段的~(10)Be沉积通量峰值显著高于末次冰期时的沉积通量峰值,表明当时黑潮对该海域已发生影响。
This paper discusses the history records of ~ (10) Be in the sedimentary core Z14-6 in the central part of the Okinawa Trough since the Last Ice Age and the Holocene and is consistent with the record of ~ (10) Be recorded in the borehole DGKS9603 in the northern Okinawa Trough comparing. Gravity columnar core Z14-6 taken from the Okinawa Trough underwater 739m (27 ° 07’N, 127 ° 27’E), a total length of 8.96m. Twelve horizons in the Late Pleistocene and Holocene (2 ~ 175cm, span of 0.37 ~ 29.3kaB.P.) Were selected and the content of ~ (10) Be was determined by accelerator mass spectrometry. The average content of ~ (10) Be in Z14-6 is 6.10 × 10 ~ 8 atoms / g and the highest value is 8.7 ka × 10 ~ 8 atoms / g in the 6.3 kaB.P. The content is generally low. Compared with the data of DGKS9603 (28 ° 08.869’N, 127 ° 16.238’E; water depth 1100m, core length 585cm), the content of ~ (10) Be in Z14-6 was generally low. The average flux of ~ (10) Be deposited in the pores of Z14-6 was 1.04 × 10 ~ 9 atoms / cm ~ 2 · ka and the highest value (1.36 × 10 ~ 9 atoms / cm ~ 2 · ka) appeared at 6.3kaB. In the P. layer, the lowest value (6.45 × 10 ~ 8 atoms / cm ~ 2 · ka) appears at the horizon of 9.27kaB.P. The water depth of Z14-6 was shallow, and the Kuroshio current did not flow through the Z14-6 hole in the last glacial period, so the ~ (10) Be sedimentation flux was only equivalent to the atmospheric average productivity of ~ (10) Be (1.21 × 10 ~ 9 atoms / cm ~ 2 · ka). The decrease in the deposition flux of ~ (10) Be in Z14-6 wells may be related to several low-temperature events, and the decrease of ~ (10) Be flux in Z14-6 wells at about 3kaB.P. and 9kaB.P. Kuroshio produced a big change. The peak of sediment flux of ~ (10) Be in some wells of Z14-6 was significantly higher than that of the last glacial during some time in the Holocene, indicating that the Kuroshio had affected the area at that time.