The southern margin of the Ordos Block (S-OB) is located in the western part of the southern region of the North China Craton (S-NCC), and has been involved in multiple orogenic episodes that uplifted the North Qinling Orogenic Belt (NQB). Determining whether the S-OB deposits and sources were controlled by late Precambrian or Ordovician tectonic sedimentation is extremely important for understanding the paleo-tectonic evolution of the S-NCC and its relationship with the North Qinling Terrane (NQT). In this study, the depositional age and trace of the source area of the Tangwangling Group (TWL) were constrained using detrital zircon U-Pb isotopic analyses. Six sandstone samples collected from the TWL Group yielded similar detrital zircon age patterns, with four distinct clusters at 2588-2305 Ma, 2100-1600 Ma, 1251-1005 Ma 995-744Ma which correspond to peak ages of 2.45 Ga, 1.80 Ga, 1.10 Ga, and 0.82 Ga, respectively. The youngest zircon ages that peak at 0.82 Ga suggest that the depositional age of the TWL Group is the closest to the late Neoproterozoic, based on comparisons with geochronological data from late Precambrian and Ordovician successions that outcrop in the OB. The detrital zircon age ranges of the TWL Group, in comparison with those of the NCC and NQT, also indicate that clastic grains deposited in the TWL Group were mainly sourced from NCC basement rocks and less so from the late Precambrian NQT complex, which was coincident with a Grenvillian-aged tectonomagmatic event. Thus, we conclude that the NQT had accreted onto the S-NCC before the TWL Group were deposited during the late Neoproterozoic, implying that the S-NCC or the S-OB may have experienced or was at least influenced by the assembly and breakup of Rodinia.

鄂尔多斯地块（S-OB）的南缘位于华北克拉通（S-NCC）南部地区的西部，并参与了多次造山活动，使北秦岭造山带（NQB）抬升）。确定S-OB的沉积和来源是受前寒武纪或奥陶纪构造沉降控制的，对于理解S-NCC的古构造演化及其与北秦岭地层（NQT）的关系极为重要。在这项研究中，使用碎屑锆石U-Pb同位素分析限制了汤王岭组（TWL）的沉积年龄和源区的痕迹。从TWL组收集的六个砂岩样品产生了类似的碎屑锆石年龄模式，在2588-2305 Ma，2100-1600 Ma，1251-1005 Ma 995-744Ma，分别对应于2.45 Ga，1.80 Ga，1.10 Ga和0.82 Ga的峰值年龄。锆石最年轻的年龄在0.82 Ga处达到峰值，这表明TWL组的沉积年龄最接近新元古代晚期，这是根据与前OB露头的前寒武纪和奥陶纪演替的年代学数据进行比较得出的。与NCC和NQT相比，TWL组的碎屑锆石年龄范围也表明，沉积在TWL组的碎屑颗粒主要来自NCC基岩，较少的是来自前寒武纪NQT复杂岩体，这是一致的伴有格伦维利亚人的年龄构造事件。因此，我们得出结论，在新元古代晚期，TWL群沉积之前，NQT已增生到S-NCC上，