爪哇海末次冰盛期以来的季风与穿越流活动记录

MONSOON AND THROUGHFLOW ACTIVITY RECORDS IN THE JAVA SEA DURING THE LAST GLACIAL MAXIMUM

文章通过SHl9034岩芯氧同位素曲线、AMS ^14C测年、浮游有孔虫组合及其所反映的温盐变化特点，并与爪哇海北部的SHl9006岩芯对比研究，获得如下认识：末次冰期2l～15kaB．P．阶段，爪哇海区东南季风强而西北季风微弱，气候冷干，混合层薄，生物生产力高；15～10kaB．P．和10～7kaB．P．阶段由于海平面迅速上升，望加锡海峡和龙目海峡通道变宽，出现较强的表层穿越流活动；早全新世东南与西北季风都有增强，说明当时研究区气候有着更强的季节性；7～3kaB．P．阶段，爪哇海北部的穿越流主要在温跃层水中传输，到达爪哇上升流区时，上升至表层，使得混合层增厚，同时也抑制了上升流活动；约3kaB．P．以来，研究区穿越流活动表现与现代相近的性质，主要在温跃层水中传输。

The core SHI9034 is obtained from the south Java Sea,blow the present Java Upwelling. Based on analyses of δ^18O,AMS ^14C ages,and planktonic foraminiferal assemblages, on sea surface temperature and salinity estimated by the planktonic foraminifera Modern Analog Technique,and on the comparison with the core SHI9006 in the north Java Sea,we have the following results： During the last glacial period 21 - 15kaB. P., the Southeast monsoon was strong and the Northwest monsoon was weak. The climate was cool and dry. Increased mixing of the surface waters led to a rise in paleoproductivity. During 15 - lOkaB. P. and 10 -7kaB. P. periods, due to rapid sea level rising, the pathways in the Makassai Strait and the Lombok Strait was broadened and the surface Indonesian throughflow boosted up. The SE Monsoon and NW Monsoon seem to be strengthened in Early Holocene, indicating that the biannual monsoonal system was mostly intense at this time. Between 7kaB. P. and 3kaB. P., the ITF in the north Java Sea transported mainly within the thermocline. The ITF rose to surface waters when it flowed into the Java Upwelling region,which made the mixed layer thickened,and restrained upwelling activity. Since ca. 3kaB. P., the ITF as we know today,transported mainly within the thermocline.