Middle–Late Cenozoic Stepwise Deformation Propagation in Eastern Tibet

Abstract

How the Tibetan Plateau uplifted and deformed is among the most interesting topics in geosciences. Various lines of investigation have suggested different uplift histories and competing models of plateau growth, including stepwise plateau growth with brittle crustal extrusion (Tapponnier et al., 2001) and channel flow in the middlelower crust (Clark & Royden, 2000;Royden et al., 2008). The remarkable high-elevation and low-relief landscape across eastern Tibet is deemed to record the region-scale surface uplift history (Clark et al., 2006;Royden et al., 2008;Zhao et al., 2021) and has been a central focus of this debate. Early studies argued that the rapid incision of rivers into the relict surface in the Late Miocene (15-10 Ma) was an indicator of the initial surface uplift across eastern Tibet (

Middle Miocene Onset of the Litang Fault System Records Kinematic Change in Eastern Tibet

“…The kinematic features of the Zhongdian‐Red River faults together with the Jiali‐Parlung faults bounding the Chuandian block to the southwest also point to NW‐directed compression (Figure 12c). Taken together, the deformation styles along major strike‐slip faults in the Chuandian block consistently indicate NW‐directed compression in middle Miocene times, resulting in the reactivation of the Yalong thrust in the junction of the Yangtze craton and Tibetan terranes (Pitard et al., 2021; Shen et al., 2019; Tao et al., 2023; Tian et al., 2013). This period of compressive deformation affected large regions beyond the Chuandian block, and reactivated the bounding faults of the Bayan Har block, such as the Kunlun fault and Longmen Shan thrust belts (Duvall et al., 2013; Shen et al., 2019; Tian et al., 2013; E. Wang et al., 2012; S. Wang et al., 2012).…”

“…We thus proposed that the co‐existence of localized and diffuse deformation accommodates tectonic extrusion of the micro‐blocks in eastern Tibet, consistent with the deformation pattern derived from present‐day GPS (Wang & Shen, 2020; Zhang et al., 2004; Figure 12d). The extruding micro‐blocks deform via both strike‐slip faulting internally and via thrusting along the southeastern margins of the plateau (Pitard et al., 2021; Shen et al., 2019; Tao et al., 2023; Tian et al., 2013). The consistency of the strike of major strike‐slip faults in the Chuandian block with the direction of GPS velocities suggests that this active tectonic framework has been largely established in eastern Tibet since middle Miocene times.…”

“…The initiation ages of these thrust belts are dated to be late Oligocene‐early Miocene. The rapid exhumation of their hanging walls (Cao et al., 2019; Tao et al., 2023; E. Wang et al., 2012; S. Wang et al., 2012; Zhu et al., 2021) was related to a widespread NW‐directed crustal shortening (Cao et al., 2019), leading to the generation of topographic relief along the southeastern Tibetan margin (Cao et al., 2019; Zhu et al., 2021). The middle‐late Miocene rapid exhumation appears restricted to the neotectonics and river gorges in eastern Tibet (Cao et al., 2022).…”

“…The initiation ages of these thrust belts are dated to be late Oligocene-early Miocene. The rapid exhumation of their hanging walls (Cao et al, 2019;Tao et al, 2023;E. Wang et al, 2012;S.…”