Clarifying the role of mountain-building processes in the filling history of large hinterland basins is an essential aspect of basin–mountain system research. We consider the case of the Triassic South Ordos Basin (SOB) to clarify these points. Located in the south-western North China Block (NCB), the SOB which preserves the most complete Triassic deposition on the north of the Qinling Orogenic Belt (QB) is crucial for understanding the detailed tectonic processes of the QB. Sedimentological, petrological and zircon U–Pb geochronological signatures from the three parts (eastern, central and western) in the SOB indicate that the sediment source migrated both temporally and spatially. Stratigraphic correlation identified two fluvial progradational episodes from south to north in the fluvial–deltaic–lacustrine sedimentary system, one in the eastern SOB and the other in the central SOB. The Late Triassic detrital zircons in the central SOB with distinguishing Neoproterozoic ages were derived from the southern margin of the NCB and the QB. The western SOB exhibited the sediment source shifted from pre-Triassic North Qilian Belt sedimentary cover to basement from the Middle-to-Late Triassic based on a zircon age transition from ca. 2000 to ca. 430 Ma. Late Triassic sediment sources also included the southern margin of the NCB and the QB. Differing provenances from east to west were also confirmed using thin section and heavy mineral analyses. Regional comparisons of zircon age distributions in the eastern SOB with published data indicate that detritus from the QB was first transported to the eastern SOB and then to the central and western SOB. Spatiotemporal changes in the sediment source and sedimentary filling transitions in the three parts of the SOB suggest that the QB underwent asynchronous uplift that began in the east during the Early Triassic and propagated westward, reaching its maximum extent in the early Late Triassic.

中文翻译：

---

鄂尔多斯盆地南缘三叠纪物源时空迁移：洞察东古特提斯洋构造演化

阐明造山过程在大型腹地盆地充填历史中的作用是盆山系统研究的一个重要方面。我们以三叠纪南鄂尔多斯盆地（SOB）为例来阐明这些观点。位于华北地块西南部的SOB，是秦岭造山带以北保存最完整的三叠纪沉积物，对于了解QB的详细构造过程至关重要。SOB东、中、西三部分的沉积学、岩石学和锆石U-Pb年代学特征表明沉积物源在时间和空间上发生了迁移。地层对比发现了河流-三角洲-湖泊沉积体系中从南到北的两段河流进积期，一期位于SOB东部，另一期位于SOB中部。中部SOB的晚三叠世碎屑锆石具有明显的新元古代年龄，来源于华北盆地和QB的南缘。西部SOB显示沉积物来源从前三叠世北祁连带沉积盖层转移到中晚三叠世的基底，基于大约1970年的锆石年龄转变。2000 至 约。430马。晚三叠世沉积物来源还包括NCB和QB的南缘。通过薄片和重矿物分析也证实了东西方不同的来源。东部SOB锆石年龄分布与已发表数据的区域比较表明，来自QB的碎屑首先被输送到东部SOB，然后到达中部和西部SOB。SOB三个部分沉积物来源和沉积充填转换的时空变化表明QB经历了​​异步抬升，该抬升在早三叠世从东部开始并向西扩展，在晚三叠世早期达到最大程度。