Eolian dust deposition and paleo-environmental changes in East Asia since the last Interglacial period

我在日本北海道的Nayoro盆地、福岛县的Yanohara沼地、福井县的Nakaikemi baisin和兵库县的Kuroi盆地收集了4个自末次间冰期以来沉积的泥炭钻探岩心。此外，还在岐阜县谷谷沼泽和济州岛收集了末次冰期以来沉积的泥炭和粘土的2个钻孔岩心。6个岩心显示末次间冰期以来东亚地区的气候变化、风向和极锋位置等气候特征。在MIS 5和MIS 1期间，以夏季风为主，河流物质在盆地和沼泽中沉积。随着极锋向北海道北部移动，中国内陆沙漠地区的风沙被西风带吹来。末次冰期，极锋向濑户内海迁移。北海道和濑户内海之间的西北冬季季风将风成沙尘从前寒武纪岩石区和露出的海底输送过来。末次冰期第24至第1间冰期，河流物质沉积。另一方面，风沙沉积增加在寒冷时期，如海因里希事件。末次冰期渐冰期和急冰期风沙中径呈锯齿状波动。14 ka后，风沙沉积减少，河流物质中值直径增大。所得模式与沙尘沉降与气候变化的一般对应关系是一致的。六个岩心的风沙记录也显示了极地地区的风沙记录的趋势。

I collected the four drilling cores of peat deposited since the last Interglacial period from Nayoro basin in Hokkaido, Yanohara moor in Fukushima Prefecture, Nakaikemi baisin in Fukui Prefecture and Kuroi basin in Hyogo Prefecture in Japan. In addition to those areas, I collected two drilling cores of peat and clay deposited since the last glacial period from Tanigumi moor in Gifu Prefecture and Cheju Island in Korea. Six cores show following climatic features as inferred from eolian dust analysis: climatic changes, wind direction, and the location of polar front in East Asia since the last Interglacial period.Summer monsoon was predominantly and fluvial material deposited in the basins and moor by the increased summer rain during MIS 5 and MIS 1. As the polar front shifted to the North Hokkaido, eolian dust was transported from the inland desert areas in China by westerlies. In the last glacial period, the polar front migrated to the Seto Inland Sea. Eolian dust was transported from the Precambrian rock areas and the emerged sea floor by the NW winter monsoon between Hokkaido and the Seto Inland Sea. In Interstadials 24 to 1 during the last glacial period, fluvial material deposited. On the other hand, eolian dust deposition increased in the cold periods such as Heinrich events. The median diameter of eolian dust fluctuated with a saw-tooth shape provoked by the gradual glaciation and abrupt deglaciation during the last glacial period. After 14 ka, eolian dust deposition decreased, and median diameter of fluvial material increased. Obtained pattern is in agreement with the general correspondence between dust deposition and climatic changes. Eolian dust record from six cores showed trends also seen in dust records from polar regions.