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本文提供玛纳斯湖两个长约５ｍ柱样的研究结果，并据此讨论新疆西部晚第四纪古气候演化。研究内容包括沉积物的矿物组成、自生碳酸盐的稳定同位素组成、孢粉组合等；用加速器质谱（ＡＭＳ）测定碳酸盐或有机质的（１４）Ｃ年龄。讨论了δ（１８）Ｏ剖面与亚洲夏季季风的关系。柱样的研究结果表明：玛纳斯湖地区晚更新世的３７０００─３２０００ａＢ．Ｐ．气候潮湿，而后又回到末次冰期的极端干旱气候。１２０００─１００００ａＢ．Ｐ．一个短暂的暖湿事件以后是以干旱为主的晚更新世─全新世过渡期；约在１００００ａＢ．Ｐ．气候明显转为温暖，草原植被取代了荒漠植被，覆盖了整个玛纳斯湖流域，沉积物自生碳酸盐的δ（１８）Ｏ低值对应暖湿气候，为亚洲夏季风盛行期；早、中全新世气候比现时暖湿，但也有几次短时间干旱。６０００─５０００ａＢ．Ｐ．有一个湖泊收缩期，玛纳斯湖地区又回到沙漠化植被；第二潮湿事件发生在４５００─２５００ａＢ．Ｐ．，其间大约３８００─３５００ａＢ．Ｐ．也曾有短时间干旱。全新世最后的２５００ａ气候不稳定，并逐渐过渡到湖泊的盐化阶段。
This paper provides the findings of two 5m long samples of Manas Lake and discusses the paleoclimatic evolution of late Quaternary in western Xinjiang. The study includes the mineral composition of sediments, the stable isotope composition of authigenic carbonate, sporopollen assemblage, etc .; the (14) C age of carbonate or organic matter was determined by accelerator mass spectrometry (AMS). The relationship between the δ (18) O profile and the Asian summer monsoon is discussed. The results of the column samples show that the late Pleistocene in the Manas Lake region is 37000-32000aB. P. The climate is humid and then returns to the extreme arid climate of the last ice age. 12000 ─ 10000ab. P. A brief warm-humid event followed a drought-dominated late Pleistocene-Holocene transitional period; at about 10,000 aB. P. The climate changed obviously to warm. Vegetation replaces the desert vegetation and covers the entire Manasi Lake basin. The low δ (18) O value of sedimentary carbonate is corresponding to the warm and humid climate, which is the prevailing summer monsoon in Asia. Mid-Holocene climate warmer than the current wet, but there are several short-term drought. 6000 ─ 5000aB. P. There is a lake contraction, Manas Lake area has returned to desertification vegetation; the second wet event occurred in 4500 ─ 2500ab. P. , During which about 3800 ─ 3500aB. P. There have also been short periods of drought. The last 2500a of the Holocene climate instability, and gradually transition to the salinization stage of the lake.