The lower palaeozoic strata had suffered many tectonic denudation in the Akekule lobe, the middle Caledonian and early Hercynian tectonic movement play the important role for oil and gas among all the factors. Firstly, by calculating the denudation of the upper Ordovician in early Hercynian tectonic movement by thickness trend method, the results reflect that the denudation occurs in main part of Tahe in the middle Akekule lobe and become thinning to the north and south. It indicates the structural characteristics before early Hercynian was high in the south east and lower fn northwest, and became denudation regions in northwest. Based on this results, we got denudation amount of middle Caledonian by the second denudation calculation. It reveals that the denudation occurred in the entire region and had denudation characteristics of strong in the north and weak in the south. So the recovery Paleostructure characteristics is high in the northwest and low in the southeast low before middle Caledonian, which confirmed Akekule lobe had been formed in this time period. The method has important guiding role to recover paleogeographic environment and to evaluate for oil and gas reservoirs.%阿克库勒凸起下古生界地层遭受多期构造运动的剥蚀,其中对油气有重大作用的主要有加里东中期和海西早期构造运动.运用地层厚度趋势法原理,首先计算出上奥陶统在海西早期的剥蚀量,反映出剥蚀发生在阿克库勒凸起中部塔河主体部位,向南北方向减薄.并恢复出海西早期前的构造特征为北西高南东低且在北西地区为剥蚀暴露区的特征,在此基础上按厚度趋势法进行二次剥蚀计算,获得加里东中期的剥蚀量,揭示出该期剥蚀发生在全区且具北强南弱特征,恢复出加里东中期前的古构造特征为北西高南东低特征,证实了阿克库勒凸起在此时期已经形成.方法对还原古地理环境,对储层的油气评价有重要的指导作用.
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