摘要
通过对共和盆地东部风成沉积的地球化学分析,并结合14C和OSL年代,重建了区域末次盛冰期以来气候变化过程。21 ka BP之前气候寒冷偏湿,21～15.82 ka BP为末次盛冰期(LastGlacial Maximum,LGM),气候极为寒冷干燥;15.82～9.5 ka BP气候转暖且偏干,其中14.5～13.6ka BP和11.9～9.5 ka BP气候明显冷干,分别为老仙女木时期(Oldest Dryas,OD)和新仙女木时期(Younger Dryas,YD),而15.82～14.5 ka BP和13.6～11.9 ka BP(BФlling-AllerФd暖期,B/A)相对温暖;9.5～7.2 ka BP暖湿程度明显提高,7.2～5.1 ka BP气候波动频繁,相对冷干和相对暖湿多次更替。5.1～2.7 ka BP暖湿程度基本稳定,之后气候趋于寒冷但湿度明显较大。这些气候变化过程与青藏高原大量的古气候信息记录具有良好的一致性,表明共和盆地气候变化与青藏高原气候变化的高度一致性。
The climatic change since the Last Glacial Maximum （LGM） period was reconstructed based on the analysis of geochemical characteristics of the aeolian deposits in Gonghe Basin, northeastern Qinghai-Tibetan Plat- eau, coupled with the 14C and OSL chronology. The cold and wet climate dominated the region before 21 ka BP, and the climate became very cold and dry in 21 - 15.82 ka BP, corresponding to the LGM period. From 15.82 to 9.5 ka BP, the regional climate tended to be warm and dry in general. During this period, the cold and dry condi- tion occurred in 14.5 -13.6 ka BP and 11.9-9.5 ka BP, implying the Oldest Dryas and Younger Dryas phases, while the relatively warm climate was found in 15.82 - 14.5 ka BP and 13.6 - 11.9 ka BP （Bolling-Allercd peri- od, B/A period）. The warm and humid degree obviously increased between 9.5 and 7.2 ka BP, marking the rela- tively warm and wet condition. The cold-dry and warm-humid climate fluctuated in 7.2 - 5.1 ka BP. In 5.1 - 2.7 ka BP, the degree of warm and wet is relatively stable but it tended to be cold with high moisture since 2.7 ka BP. These changes are coincident with the paleoclimatic records in Qinghai-Tibetan Plateau, reflecting higher consisten- cy in climatic change between Gonghe Basin and Qinghai-Tibetan Plateau.
出处
《地球科学进展》
CAS
CSCD
北大核心
2012年第7期788-799,共12页
Advances in Earth Science
基金
国家自然科学基金项目"晚第四纪以来中国季风区西北缘沙漠演化及其对全球变化的响应"(编号:40971005)资助
关键词
共和盆地
地球化学
风成沉积
末次盛冰期
Gonghe Basin
Geochemical
Aeolian deposit
Last Glacial Maximum（LGM） period.
