Liu Fangbin, Wang Min
School of Geography and Tourism, Qilu Normal University, Ji'nan, 250200, China.
Key Laboratory of Western China's Environmental Systems, Ministry of Education, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, 730000, China.
Heliyon. 2024 Sep 1;10(17):e37218. doi: 10.1016/j.heliyon.2024.e37218. eCollection 2024 Sep 15.
The Liupan Shan, situated on the southwestern Ordos Basin, underwent Cenozoic uplift caused by the India-Asia collision and subsequent northeastward tectonic movements. The strata in this region record both the paleogeography of the southwestern Ordos Basin and the uplift history of the Tibetan Plateau. However, past studies have rarely analyzed the strata comprehensively, resulting in overlooked information within them. We present the first detrital zircon (U-Th)/He (ZHe) data from the Lower Cretaceous deposits of the Liupan Shan and the Upper Miocene red clay of Chaona, constraining a maximum burial depth of less than 6-7 km at 60 Ma for the Liupan area. By integrating zircon U-Pb ages, paleocurrent data, and sedimentary facies, we found a primary ZHe age peak (∼210 Ma) indicating that the Lower Cretaceous deposits were sourced from the Qinling Orogenic Belt, while the red clay was likely originated from the Liupan Shan. Although the Chaona strata are not preserved in the Liupan Shan, our results suggest that the Miocene Chaona section is crucial for understanding the Late Cenozoic uplift of the Liupan Shan. The distinct stratigraphic ages and source areas reflect the complex depositional and tectonic history of the region. Thermal modeling results revealed three stages of tectonic events (Late Cretaceous, Late Paleocene-Early Eocene, and Late Cenozoic), which are linked to plate interaction. Our findings offer new insights into the long-term tectonic evolution of the Tibetan Plateau.
六盘山脉位于鄂尔多斯盆地西南部,经历了由印度-亚洲碰撞及随后的东北向构造运动导致的新生代隆升。该地区的地层记录了鄂尔多斯盆地西南部的古地理以及青藏高原的隆升历史。然而,过去的研究很少对地层进行全面分析,导致其中的信息被忽视。我们展示了六盘山下白垩统沉积物和朝那上中新世红粘土的首批碎屑锆石(U-Th)/He(ZHe)数据,确定了六盘地区在60 Ma时最大埋藏深度小于6 - 7千米。通过整合锆石U-Pb年龄、古水流数据和沉积相,我们发现一个主要的ZHe年龄峰值(约210 Ma),表明下白垩统沉积物来自秦岭造山带,而红粘土可能源自六盘山。尽管朝那地层在六盘山未被保存下来,但我们的结果表明,中新世朝那剖面对于理解六盘山晚新生代隆升至关重要。不同的地层年龄和物源区反映了该地区复杂的沉积和构造历史。热模拟结果揭示了与板块相互作用相关的三个构造事件阶段(晚白垩世、晚古新世-早始新世和晚新生代)。我们的发现为青藏高原的长期构造演化提供了新的见解。