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在对西天山赛里木湖盆地进行第四纪地质调查与5万填图基础上,发现沿该湖泊的不同湖岸阶地上都不同程度地发育了可指示湖面变化的湖滩岩。水准测量结果表明,典型的湖滩岩最常见于高出现今湖面7.1~9.4 m和33.4~39.4 m的低、高两级湖积台地上。对湖滩岩样品进行岩石学和矿物学研究进一步揭示,湖滩岩主要由内碎屑、藻团块、陆源碎屑、胶结物和填隙物等构成,胶结物主要为亮晶方解石,夹少量文石,表明赛里木湖周边的湖滩岩为典型的方解石胶结砂屑砾屑岩。湖滩岩样品的U系年代测试结果表明,低、高两级台地上的湖滩岩主要形成于距今24.8±1.5 ka至27.6±1.5 ka和55.4±3.8 ka的晚更新世晚期,大致对应末次冰期间冰阶MIS3阶段早期和末期的相对暖湿气候阶段。湖滩岩及其测年结果指示,赛里木湖最近一期最高湖面出现在距今55.4 ka左右末次间冰阶早期,其后由于气候的干旱化,湖面整体处于逐步下降过程,在相对暖湿期间经历了多次湖面相对稳定期并形成湖滩岩。
Based on the Quaternary geological survey and 50,000 mapping of the Sailimu Basin in the West Tianshan Mountains, it is found that the lake and beach rocks that can indicate the change of the lake are developed to different extents along different lakeshore terraces. The leveling results show that the typical lacustrine rocks are most commonly found on low and high level lacustrine platforms 7.1 ~ 9.4 m and 33.4 ~ 39.4 m higher than the present lake. Petrological and mineralogical studies on the samples of lacustrine rocks further reveal that the lacustrine rocks are mainly composed of internal debris, algal agglomerates, terrigenous debris, cements and interstitials. The cements are mainly calcite, A small amount of aragonite indicates that the lagoon rocks surrounding the Lake Limi are typical calcite-cemented sand and gravel rocks. The results of the U-line dating of the samples of the Hu Tan rock show that the lake-beach rocks on the low-high and high-level platforms mainly formed in the late Late Pleistocene from 24.8 ± 1.5 ka to 27.6 ± 1.5 ka and 55.4 ± 3.8 ka, roughly corresponding to The relatively warm and wet climatic phases of the early and late MIS3 phases of the ice stage during the last ice. The lacustrine rock and its dating results indicate that the highest lacustrine lake in the last stage of the Sereimu Lake occurred at the last intergalactic period of about 55.4 ka, and the subsequent lacustrine weather was gradually declining due to the arid climate. As a result, Wet period has experienced a number of relatively stable lake and the formation of beach rock.