Meso-Cenozoic tectonic and fluid evolution and uranium mineralization in the Kuqa depression
In this paper,the basin modeling method was used to construct the structural morphology of the Mesozoic and Cenozoic layers in Kuqa depression of Tarim basin by analysis of the structural deformation characteristics of a series of sections.A comprehensive investigation on the Meso-Cenozoic tectonic evolution of the Kuqa depression was conducted using apatite fission track,apatite(U-Th)/He,and balanced cross-section methods,the fluid evolution process of key layers was simulated,the relationship between the Meso-Cenozoic tectonic and fluid evolution of the Kuqa depression and sandstone-type uranium mineralization was discussed.The results show that the structural deformation strength of Kuqa depression is characterized as"strong in the west and weak in the east".The study area experienced three important cooling events during the Late Jurassic-Early Cretaceous,Paleogene to Miocene and Pliocene to Quaternary,which were caused by the collage of Lhasa terrane and Eurasian plate,Kohistan-Dras island arc accretion,and progressive collision between the Indian and Eurasian plate,respectively.Oil and gas leakage phenomenon is obvious in the Neogene of Kuqa depression,mainly distributed along the Kelasu,Yiqikelike and Qiulitage structural belts.The hydrocarbon is mainly derived from deep Triassic and Jurassic source rocks,and there are two stages of hydrocarbon leakage from 23 Ma to 5 Ma and from 5 Ma to present.The oxygenated uranium containing water in Kuqa depression is mainly supplied by the South Tianshan Mountain,and partly by Qiulitage structural belt.The seepage fluid migrated from the Baicheng depression to the Linear fold belt in the form of"convergent flow and surface flow",and migrated southward to Qiulitage structural belt in the form of"surface flow",and pooled in the Uplift belt.The tectonic and fluid evolution controlled the sandstone uranium mineralization in the Kuqa depression,showing the characteristics of"early interlayer oxidation and late exudation relay mineralization".
tectonic evolutionpalaeofluidoil and gas reductionsandstone type uranium depositthe Kuqa depression
万方数据
维普
