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运用碎屑锆石LA-ICP-MS锆石U-Pb测年方法,结合碎屑锆石矿物特征、阴极发光图像和年龄谱分布特征,对鄂尔多斯盆地西南缘麟游地区二叠系上石盒子砂岩进行了碎屑物源分析。结果表明:碎屑锆石U-Pb年龄分布主要包含3组峰值年龄:1864 Ma、2500 Ma和441 Ma,另外具有一颗3.3 Ga古老的碎屑锆石年龄及一组次级年轻年龄组299～363 Ma。1864 Ma和2500 Ma两组峰值的锆石颗粒约占总体的82.2%,表明二叠纪末上石盒子期华北克拉通为鄂尔多斯盆地西南缘提供主要物源,3.3 Ga年龄的存在也指示其来源于华北克拉通;441 Ma峰值的锆石颗粒约占总数的10.4%,指示其可能来自秦岭-祁连造山带,由于缺少800～1000 Ma的新元古代年龄,表明秦-祁造山带在上石盒子期抬升及剥蚀程度较低;299～363 Ma年龄组指示其可能来源于华北克拉通北缘的兴-蒙造山带岩浆弧。
Based on zircon U-Pb zircon dating from detrital zircons and combined with the features of detrital zircon minerals, cathodoluminescence images and age distribution, the Permian upper Shihezi block in Linyou area, southwestern margin of Ordos Basin, Sandstone debris source analysis. The results show that the age distribution of detrital zircon U-Pb mainly consists of three groups of peak age: 1864 Ma, 2500 Ma and 441 Ma, in addition to a 3.3 Ga ancient detrital zircon age and a group of secondary young age group 299 ~ 363 Ma. The zircons of the two sets of peaks at 1864 Ma and 2500 Ma account for 82.2% of the total, indicating that the North China Craton of the Permian last Upper Lithofacies period provided the major source for the southwestern margin of the Ordos Basin. The occurrence of 3.3 Ga ages also indicated its origin In the North China Craton, the 441 Ma peak zircon grains account for about 10.4% of the total, indicating that they may come from the Qinling-Qilian orogenic belt. Due to the lack of the Neoproterozoic age of 800-1000 Ma, it indicates that the Qin- The shelf uplift and denudation of the stone box are lower; the 299-363 Ma age group indicates that it may have originated from the Xing-Menggao magmatic arc in the northern margin of the North China Craton.