Tectonics of the Eastern Kunlun Range: Cenozoic Reactivation of a Paleozoic‐Early Mesozoic Orogen

Abstract

The Eastern Kunlun Range in north Tibet, located along the northern margin of the eastern Tethyan orogenic system, records evidence for continental break‐up and ocean development in the Neoproterozoic, Paleozoic‐early Mesozoic subduction and continental collision, Mesozoic intracontinental extension, and Cenozoic contractional deformation. The Kunlun region is marked by active left‐lateral strike‐slip deformation of Kunlun fault system, one of the major intracontinental strike‐slip faults in Tibet that developed in response India‐Asia. To better constrain the tectonic evolution of the Eastern Kunlun Range and the closure of the various Kunlun oceans, we conducted detailed investigation integrating new geologic mapping, geochronology, and whole‐rock geochemistry with a synthesis of existing datasets across north Tibet. The Eastern Kunlun Range experienced three major deformation events in the Neoproterozoic, early Paleozoic, and Late Paleozoic‐early Mesozoic, which were associated with collision of the Proto‐, Paleo‐, and Neo‐Kunlun arcs, respectively. Our new detrital zircon analyses from Mesoproterozoic‐Cenozoic strata constrain stratigraphic age and sediment provenance and highlight the importance of three periods of arc activity. Our stratigraphic synthesis, including new field observations, provides new insights into connections between sediment dispersal and changes in tectonism and paleogeography. Miocene‐to‐present strike‐slip activity on the Kunlun fault and the associated strain pattern can be explained by clockwise rotation of the Kunlun fault and its wall rock as a bookshelf‐fault system, which has been proposed for northern Tibet as a result of distributed north‐south right‐lateral shear. The development of this fault system was facilitated by the presence of a Triassic suture that provided a preexisting weakness.

Detrital zircon provenance comparison between the Paleocene-Eocene Nangqian-Xialaxiu and Gongjue basins: New insights for Cenozoic paleogeographic evolution of the eastern Tibetan Plateau

“…To understand the growth and uplift of the Tibetan Plateau, the study of the basin development, sedimentary provenance, and depositional processes are crucial (e.g., Fielding, 1996;Clark et al, 2005;Zhu et al, 2006b;Li et al, 2012;Yuan et al, 2013;Zhang et al, 2013;Zhang et al, 2014). Previous geological investigations of the A C C E P T E D M A N U S C R I P T sedimentary records within and along the periphery of the Tibetan Plateau have significantly improved our understanding of the terrane accretion and associated tectonic deformation and uplift since the Paleozoic (e.g., Wang et al, 2001a;Otofuji et al, 2007;Pullen et al, 2008;Li et al, 2009;Dupont-Nivet et al, 2010;Zhai et al, 2011a;Ma et al, 2014;Yu et al, 2014Yu et al, , 2017Huang et al, 2015;Tong et al, 2015;Li et al, 2017Li et al, , 2018bMcRivette et al, 2019;Wu et al, 2019aWu et al, , 2019b. The India-Asia collision in the early Paleogene and the subsequent continental deformation are thought to have induced most of the plateau growth as expressed by the development of a series of foreland basins within and in the periphery of the Himalayan-Tibetan orogen (e.g., Allégre et al, 1984;Yin and Harrison, 2000;Najman, 2005;Wu et al, 2010;DeCelles et al, 2014).…”

Petrogenesis and tectonic significance of the late Devonian‐early Carboniferous Jianxiashan pluton in the western domain of the eastern Kunlun Orogen, northern Tibetan Plateau

“…The Mesozoic strata (J 1–2 , J 3 and K 1 ; Figure ) are exposed in the northern portion of our study area and consist of polymictic conglomerate arkosic sandstones and coal‐bearing shale. The study area includes numerous Cenozoic thrust faults and potential strike‐slip faults (Yin, Dang, Wang, et al, ; Yin, Dang, Zhang, Chen, & McRivette, ; Zuza et al, Zuza & Yin, , Zuza et al, ; Wu, Liu, et al, ; Wu, Zuza, et al, ). Most of the thrust faults are southwest‐dipping.…”

“…The Kunlun Orogen is located in the western part of the Central China Orogenic Belt in Mainland China and extends from east to west for nearly 3,000 km with a width of 50–200 km (Figure ). As a result of the long‐lived subduction of the Proto‐ and Paleo‐Tethys oceanic lithosphere and the subsequent continent–continent collision, the Kunlun Orogen is characterized by widespread large‐scale granitic plutons (Figure ) from the Neoproterozoic to Mesozoic, which has attracted considerable attention over the past decades (e.g., Chen, Gehrels, Yin, Li, & Jiang, ; Cowgill, Yin, Harrison, & Wang, ; Gehrels, Yin, & Wang, , ; Liu et al, ; Liu, Wu, Song, Liu, & Zhang, ; Mo et al, ; Wu et al, , ; Wu, Zuza, et al, ). However, there are different views on the opening time of the Paleo‐Tethys, such as the Carboniferous (Liu, Pei, Li, Li, Chen, et al, ; Liu, Pei, Li, Li, Zang, et al, ; Yang, Wang, Shi, Xu, & Wu, ) and Permian (Sengör, ; Yin & Harrison, ).…”

Petrogenesis and tectonic significance of Early Paleozoic magmatism in the northern margin of the Qilian block, northeastern Tibetan Plateau

“…An orogeny is commonly accompanied by widespread magmatism in the earth (e.g., Harris et al, 1986;Finger et al, 1997;Sylvester, 1998;Yin and Harrison, 2000;Yin et al, 2007;Xiao et al, 2009aXiao et al, , 2009bWu et al, 2016Wu et al, , 2017Wu et al, , 2019Zuza et al, 2018). During the different stages of an orogenic process, different magmas types can be generated (e.g., Pearce, 1983Pearce, , 1996Sylvester, 1998).…”