Low-temperature thermochronology constraints on the evolution of the Eastern Kunlun Range, northern Tibetan Plateau

Abstract

Signals of uplift and deformation across the Tibetan Plateau associated with the Cenozoic India-Asia collision can be used to test debated deformation mechanism(s) and the growth history of the plateau. The spatio-temporal evolution of the Eastern Kunlun Range in northern Tibet provides a window for understanding the intracontinental tectonic evolution of the region. The Eastern Kunlun Range exposes the Cenozoic Kunlun left-slip fault and kinematically linked thrust belts. In this contribution, integrated field observations and apatite fission-track thermochronology were conducted to constrain the initiation ages of localized thrust faults and the exhumation history of the Eastern Kunlun Range. Our analyses reveal four stages of cooling of the Eastern Kunlun Range. We relate these four stages to the following interpreted tectonic evolution: (1) an initial period of early Cretaceous cooling and slow exhumation over the early Cenozoic, which is associated with the formation of a regional unconformity observed between Cretaceous strata and early Cenozoic sediments; (2) rapid Oligocene cooling that occurred at the eastern domain of the Eastern Kunlun Range related to the southern Qaidam thrusts; (3) extensive rapid cooling since the early-middle Miocene in most of the eastern-central domains and significant uplift of the entire range; and (4) a final pulse of rapid late Miocene-to-present cooling associated with the initiation of the Kunlun left-slip fault and dip-slip shortening at the western and eastern termination of the left-slip fault. Early Cenozoic deformation was distributed along the northern extent of the Tibetan Plateau, and overprinting out-of-sequence deformation migrated back to the south with the initiation of Miocene-to-present deformation in the Eastern Kunlun Range.

Quantifying the long‐term slip rate of Liupan Shan thrust fault through the low‐temperature thermochronology

“…As shown in Figure 8a, the Early Cenozoic deformation has been documented in many localities along the NE Tibetan Plateau and adjacent areas, such as the East Kunlun Shan (e.g., Clark et al, 2010; Duvall et al, 2013; Li et al, 2021; Wang et al, 2017), North Qaidam thrust system (e.g., Cheng et al, 2016; He et al, 2018, 2022; Jolivet et al, 2001); Qian Shan (e.g., An et al, 2020; He et al, 2017; Li et al, 2020; Qi et al, 2016; Wu, Li, & Ding, 2021; Wu, Zuza, et al, 2021), the West Qinling Fault (e.g., Clark et al, 2010; Duvall et al, 2011), and some areas without our study (e.g., Liu et al, 2017; Wu et al, 2020). Furthermore, the enhanced sedimentation rates and clockwise rotation of the Xining‐Lanzhou Basin also imply deformation not long after collision (e.g., Dai et al, 2006; Dupont‐Nivet et al, 2004).…”

“…Topographic map of NE Tibetan Plateau with major faults and initial deformation timing in (a) Palaeocene to Eocene and (b) early‐late Miocene (modified from Wang et al, 2020; Yu, Zheng, et al, 2019; Yuan et al, 2013). The deformation timing data are derived from: [1]‐Duvall et al, 2013; [2]‐Wang et al, 2017; [3]‐Clark et al, 2010; [4]‐Li et al, 2021; [5]‐Duvall et al, 2011; [6]‐Wang et al, 2016; [7]‐Lease et al, 2011; [8]‐Dupont‐Nivet et al, 2004; [9]‐Dai et al, 2006; [10]‐Zhang et al, 2015; [11]‐Wu, Li, & Ding, 2021, Wu, Zuza, et al, 2021; [12]‐Qi et al, 2016; [13]‐Li et al, 2020; [14]‐He et al, 2017; [15]‐An et al, 2020; [16]‐Jolivet et al, 2001; [17]‐Yin et al, 2002; [18]‐He et al, 2022; [19]‐Cheng et al, 2016; [20]‐He et al, 2018; [21]‐Zheng et al, 2006; [22]‐Lin et al, 2010; [23]‐Wang et al, 2011; [24]‐Peng et al, 2019; [25]‐Yan et al, 2006; [26]‐Craddock et al, 2011; [27]‐Zhang et al, 2012; [28]‐Yuan et al, 2011; [29]‐Lu et al, 2012; [30]‐Pang et al, 2019; [31]‐Fang et al, 2007; [32]‐Yu, Pang, et al, 2019; [36]‐Zhuang et al, 2018; [37]‐Yuan et al, 2013; [38]‐Zheng et al, 2017; [39]‐Pang et al, 2019; [40]‐Wang et al, 2020; [41]‐Li, Chen, et al, 2019; [42]‐Wu, Li, & Ding, 2021. DCH, Dulan‐Chaka Highland; GNS, Gonghe Nan Shan; JS, Jishi Shan; LPTF, Liupan Shan thrust fault; QNS, Qinghai Nan Shan; SKB, Sikouzi Basin; XB, Xunhua Basin…”

“…Compared with the Early Cenozoic deformation, the Miocene deformation is widely distributed in the NE Tibetan Plateau and adjacent areas (Figure 8b). Low‐temperature thermochronology data from Qilian Shan (Duvall et al, 2013; Li, Chen, et al, 2019; Wang et al, 2020; Yu, Pang, et al, 2019; Yu, Zheng, et al, 2019; Zheng et al, 2017; Zhuang et al, 2018), Jishi Shan (Lease et al, 2011), Dulan‐Chaka Highland (Duvall et al, 2013; Wu, Li, & Ding, 2021), and Gonghe Nan Shan (Craddock et al, 2011) suggest the rapid exhumation during the Middle to Late Miocene of rock that lies in the hanging walls of major thrust faults. Moreover, syntectonic sedimentation in a variety of basins, erosionally driven cooling of fault‐cored ranges, became widespread across the NE Tibetan Plateau.…”

Eocene to Miocene paleoclimate reconstruction of the northern Tibetan Plateau: constraints from mineralogy, carbon and oxygen isotopes of lacustrine carbonates in the western Qaidam Basin

“…As for stage Ⅱ and Ⅲ, the tectonic evolution may have also played a role in the climatic change observed. The above three mountains surrounding the Qaidam Basin underwent extensive rapid cooling during the early-middle Miocene (Figure 9H) (e.g., Lease et al, 2011;Cheng et al, 2016;Wu et al, 2021), accompanied with the large sediment flux and basin average shortening rate (Figures 9F, G) (Bao et al, 2017). During stage Ⅱ the global temperature remains relatively stable, similar to stage Ⅰ.…”