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干旱—半干旱地区冲洪积物顶面土壤中发育的砾石钙膜含有明显的年龄信息，其厚度及由统计计算得到的累积速率可用来估算所在冲洪积物或土壤的形成年代。在阿尔金山东段北麓发育的５ 期洪积扇（中更新世晚期—全新世早期）上，砾石钙膜的厚度被进行了系统地测量。依据各期洪积扇的绝对年龄计算得到该区砾石钙膜的平均累积速率为０．０１ ｍ ｍ ／ｋａ。该值被用来对长草沟古河道及其附近断错洪积扇的形成年代进行了估算
Gravel calcium films developed in the top soil of the alluvial sediments in arid-semi-arid regions contain clear age information and their thickness and the cumulative rate calculated by statistics can be used to estimate the age of formation of alluvial or alluvial soil present. The thickness of the gravel calcium film was systematically measured in the fifth-stage alluvial fan (Late Middle Pleistocene-Early Holocene) developed at the northern foot of the eastern Altun Mountains. Calculated according to the absolute ages of the alluvial fans in each period, the average accumulation rate of gravel calcium film in this area is 0.01 m m / ka. This value was used to estimate the formation age of the fault channel in Changcaogou ancient channel and its vicinity