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吐哈盆地的砂岩主要属杂砂岩类，总的结构成熟度和成分成熟度均较低，形成于强烈剥蚀、快速搬运的沉积环境中。物源类型主要为源自大陆壳内的中、酸性火成岩。砂岩成分按分布特点以二叠纪、三叠侏罗纪以及白垩第三纪划分为三阶段，分别代表盆地三个重要演化时期。在晚二叠世，砂岩的成分成熟度及ＣＩＡ指数均较低，代表了构造活动较强的快速剥蚀、快速搬运的沉积环境，是海西运动在本区的反映；而三叠侏罗纪砂岩的成分成熟度及ＣＩＡ指数均明显提高，显示盆地发育稳定而广阔，化学风化作用加强；在中生代晚期，由于燕山及其后喜山运动的影响，使吐哈盆地及其周边地区构造活动性加强，造成砂岩的ＣＩＡ指数再次降低。
The sandstone of the Tu-Ha Basin is mainly of the type of miscellaneous sandstone, with low overall maturity and compositional maturity. It is formed in a strongly denudated and rapidly moving depositional environment. The types of provenance are mainly medium and acidic igneous rocks originating from the continental crust. The sandstone components are divided into three stages according to the distribution characteristics of Permian, Triassic Jurassic and Cretaceous Tertiary, representing three important evolutional stages of the basin respectively. In the Late Permian, the compositional maturity and CIA index of the sandstone are both low, representing rapid tectonic rapid deposition and tectonic depositional environment, which is a reflection of the Hercynian movement in this area. The Triassic Jurassic The compositional maturity and CIA index of age-proven sandstones have been significantly improved, indicating a stable and broad basin development and enhanced chemical weathering. In the late Mesozoic, due to the influence of Yanshan and its subsequent Himalayan movement, the structure of the Turpan-Hami basin and its surrounding areas Activity increased, resulting in sandstone CIA index again lower.