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在阿尔金断裂中段的当金山口北部、柴达木大门口断谷、格斯断槽等地的断裂带内, 采集到侏罗纪地层和糜棱岩化加里东期花岗岩样品, 通过岩石薄片和电子显微镜测试, 发现这些变形岩石中都出现一些与走滑韧性变形同期的新生矿物, 如绢云母、白云母、黑云母和绿泥石等. 通过对这些新生矿物的激光微区40Ar/39Ar测年, 获得了一组92～89 Ma 的等时线年龄和(46.6±6.4) Ma的表面年龄. 其中92～89 Ma的年龄组说明阿尔金断裂在晚白垩世开始发生韧性走滑运动, 并伴有低级变质作用, 这一事件与亚洲“西构造结”(尼泊尔-西昆仑山)的形成(102～85 Ma)同步.
Jurassic strata and mylonitized Caledonian granite samples were collected from the northern part of Dangjin Pass in the middle of the Altyn Tagh fault, the fault valleys in the valleys of the Qaidam main entrance, the Gess fault, etc, And electron microscopy, we found that some of these deformed rocks have some new-generation minerals, such as sericite, muscovite, biotite and chlorite, which are related to the strike-slip ductile deformation.According to the 40Ar / 39Ar Dating, a set of isochron age of 92-89 Ma and surface age of (46.6 ± 6.4) Ma were obtained, in which the age group of 92-89 Ma indicated that the ductile strike slip occurred in the Late Cretaceous of the Altyn Tagh fault, Accompanied by low-grade metamorphism, coincides with the formation of the “Western Structural Knot” (Nepal-West Kunlun Mountains) in Asia (102-85 Ma).