Late Miocene to Early Pliocene is a significant transition period of basin-mountain mechanism on the southwestern margin of Tarim basin, which laid a foundation for the current basin-mountain tectonic pattern. The sediment lithology and heavy mineral assemblages of the Miocene-Pliocene in well Qibei-3 were analyzed in this study to establish variational rules of heavy mineral characteristics in vertical direction of stratigraphic profiles. Based on contents of heavy minerals from well Qibei-3 and features of their assemblages, three mineral sections were identified from bottom to top: stable heavy mineral segment, slightly unstable heavy mineral segment, and unstable heavy mineral segment. Analysis of the source area for heavy minerals shows that the erosion area of metamorphic rock in the source area constantly increases with rising of the profile but the erosion area of intermediate and acid igneous rocks reduces. Combining with sedimentary characteristics of well Qibei-3 , this study established response relationship between tectonic events and sedimentation and classified uplifting activities of the West Kunlun during Late Miocene-Early Pliocene into three stages; the relatively stable stage during deposition of the Anju'an Formation to the lower Pakabulake Formation, the uplifting stage during deposition of the mid-upper Pakabulake Formation, and the strongly uplifting stage during deposition of the Atushi Formation in the Pliocene.%中新世晚期—上新世早期是塔里木盆地西南缘盆山作用机制发生重大转折的时期,奠定了现今的盆山构造格局.本文通过对棋北3井中新统—上新统沉积物岩性和重矿物组合的分析,建立了重矿物特征在地层剖面垂直方向上的变化规律.根据棋北3井重矿物含量及其组合随剖面向上变化的特征,自下而上可划分为稳定重矿物段、较不稳定重矿物段和不稳定重矿物段；重矿物源区分析表明,源区变质岩隆升剥蚀的分布范围随着剖面向上不断地增大,而中酸性岩浆岩分布范围在逐步减小.结合棋北3井沉积特征,提出了盆山过程的构造-沉积响应关系,并将西昆仑中新世晚期—上新世早期的隆升活动划分为中新统安居安组和帕卡布拉克组下部沉积时期的相对稳定期、中新统帕卡布拉克组中上部沉积时期的阶段隆升期阶段隆升期和上新统阿图什组沉积时期的强烈隆升期3个阶段.
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