The Paleozoic strata are widely distributed in the northwest of the Ordos Basin, and the provenance attributes of the basin sediments during this period are still controversial. In this paper, the detrital zircon LA-MC-ICPMS U-Pb age test was conducted on the drilling core samples of the Shanxi Formation of the Upper Paleozoic in the Otuokeqi area of the Ordos Basin, and the provenance age and the characteristic of the Shanxi formation in the Otuokeqi area in the northwest were discussed. The cathodoluminescence image shows that the detrital zircon has a clear core-edge structure, and most of the cores have clear oscillatory zonings, which suggests that they are magmatic in origin. Zircons have no oscillatory zoning structure that shows the cause of metamorphism. The age of detrital zircon is dominated by Paleoproterozoic and can be divided into four groups, which are 2500~2300 Ma, 2100~1600 Ma, 470~400 Ma, and 360~260 Ma. The first two groups are the specific manifestations of the Precambrian Fuping Movement (2.5 billion years) and the Luliang Movement (1.8 billion years) of the North China Craton. The third and fourth groups of detrital zircons mainly come from Paleozoic magmatic rocks formed by the subduction and collision of the Siberian plate and the North China plate. The value of zircon ranges from -18.36 to 4.33, and the age of the second-order Hf model ranges from 2491 to 1175 Ma. The source rock reflecting the provenance of the sediments comes from the material recycling of the Paleoproterozoic and Mesoproterozoic in the crust, combined with the Meso-Neoproterozoic detrital zircons discovered this time, indicating that the provenance area has experienced Greenwellian orogeny.

中文翻译：

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鄂尔多斯盆地西北部奥托科奇地区山西组碎屑锆石的U-Pb定年和Hf同位素分析

古生代地层广泛分布在鄂尔多斯盆地的西北部，这一时期盆地沉积物的物源属性仍存在争议。本文对鄂尔多斯盆地欧托科奇地区上古生界山西组钻探岩心样品进行了碎屑锆石LA-MC-ICPMS U-Pb年龄试验。讨论了西北奥托科奇地区的山西组。阴极发光图像显示碎屑锆石具有清晰的岩心边缘结构，并且大多数岩心具有清晰的振荡带，这表明它们起源于岩浆。锆石没有显示出变质原因的振荡分区结构。碎屑锆石的年龄以古元古代为主，可分为2500〜2300 Ma，2100〜1600 Ma，470〜400 Ma和360〜260 Ma四大类。前两组是华北克拉通前寒武纪富平运动（25亿年）和陆良运动（18亿年）的具体表现。第三，第四类碎屑锆石主要来自西伯利亚板块和华北板块的俯冲和碰撞形成的古生代岩浆岩。这 第三，第四类碎屑锆石主要来自西伯利亚板块和华北板块的俯冲和碰撞形成的古生代岩浆岩。这 第三，第四类碎屑锆石主要来自西伯利亚板块和华北板块的俯冲和碰撞形成的古生代岩浆岩。这锆石的值范围从-18.36到4.33，二阶Hf模型的年龄范围从2491到1175 Ma。反映沉积物来源的烃源岩来自地壳中的古元古代和中元古代的物质再循环，再加上这次发现的中新元古代碎屑锆石，表明该来源地区经历了格林威尔造山作用。