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位于帕米尔前缘逆冲推覆体(Pamir Front Thrust,PFT)东端的木什滑脱背斜,是帕米尔弧形推覆构造带最前缘和最新的变形带。对地形横剖面、纵剖面和水系发育特征的分析表明,木什背斜总体上具有由西向东扩展生长的特征。在背斜核部及北翼发育数级开阔平坦的沿轴向展布的河流阶地,阶地可划分为4期。利用阶地堆积细颗粒石英光释光测年获得阶地面T2a、T3和T4的形成年龄分别为(15.8±2.40)ka、(55.1±10.3)ka、(131.4±23.9)ka。伴随背斜的生长扩展,河流阶地面发生了横向和纵向掀斜,并形成断层陡坎和褶皱陡坎。木什背斜晚第四纪的缩短和隆升主要是通过褶皱翼旋转机制进行的,估算其最小缩短速率为(1.6±0.3)mm/a,最小隆升速率为(1.9±0.3)mm/a。与此同时,沿轴向背斜发生了向东的侧向迁移和旋转。根据背斜垂直隆升与侧向扩展之间的关系,估算背斜在131～16ka期间向东的侧向迁移扩展速率较快,为(14.6±3.6)mm/a;自16ka至今,侧向迁移扩展速率迅速减小至(1.7±0.3)mm/a,背斜向东的迁移扩展可能已基本停止,而以侧向旋转为主。
The Mishifa anticline located at the eastern end of the Pamir Front Thrust (PFT) is the foremost and latest deformation zone of the Pamir Nappe belt. The analysis of topography, longitudinal profile and water system development shows that the Mushishi anticline generally has the characteristics of expanding from west to east. In the anticlinal core and the north wing, a number of fluvial terraces distributed in the axial direction and open and flat are open and flat. The terraces can be divided into four phases. The formation ages of T2a, T3 and T4 were (15.8 ± 2.40) ka, (55.1 ± 10.3) ka and (131.4 ± 23.9) ka, respectively, from terraced sedimentary fine quartz photoluminescence dating. Along with the growth and expansion of anticlines, the horizontal and vertical tilt of the river terrace occurred, and the fault scarp and fold scarp formed. The shortening and uplifting of the Mushi anticlines in the late Quaternary were mainly carried out through the fold wing rotation mechanism. The minimum rate of shortening and the minimum uplift rate were estimated to be (1.6 ± 0.3) mm / a and 1.9 ± 0.3 mm / a. At the same time, an eastward lateral migration and rotation occurred along the axial anticline. According to the relationship between vertical uplift and lateral extension of anticlines, it is estimated that the lateral migration of anticlines from east to west during the period of 131-16 ka is very fast (14.6 +/- 3.6) mm / a, and from 16 ka to the present day, The rate of migration and expansion rapidly decreases to (1.7 ± 0.3) mm / a. The migration and extension of the anticline to the east may have basically stopped but the lateral rotation is the main factor.