The characteristics of active deformation and strain distribution in the eastern Tian Shan

Abstract

The Tian Shan is one of the largest and most active intracontinental mountain belts, and its active deformation has attracted much scientific attention. In this study, we investigated the characteristics of active deformation in the most complex, eastern Tian Shan through the analysis of focal mechanism solutions since 1976, velocity vectors of 25 years geodetic measurements, and existing studies on active tectonics. The results demonstrate that: (a)~3.5 mm/year of convergence is accommodated by the southern Junggar fold-and-thrust belt, forming a series of active thrusts and folds. The Bolokelu-Aqikekuduke Fault is a transpressional structure, accommodating~1 mm/year shortening and~1.5 mm/year of right-lateral shear strain; (b) Most of the convergence in the Huola Shan region is absorbed by the North Luntai Fault, and the right-lateral shear strain is probably accommodated by the Kaidu River Fault and the Songshudaban Fault; (c) Active deformation in the eastern Tian Shan under oblique convergence is mainly partitioned into widespread compressional deformation (folding and thrusting) and dextral displacements on the NW-trending faults. Nevertheless, left-lateral strike-slip motions have also been observed, suggesting that further constraints on the kinematics and deformation rates of structures especially the intermontane structures are still needed with the aim of achieving a better understanding of strain distribution in the study area.

Retracted: Control of Multiple Detachments on Structural Development in the Southern Junggar Fold‐and‐Thrust Belt, Northern Tian Shan: Implications for Seismic Hazard Assessment

“…The Tian Shan is an active intracontinental mountain belt, accommodating ∼20 mm/yr of present‐day convergence between the Indian and Eurasian plates in its western part and ∼8 mm/yr in its eastern part (Abdrakhmatov et al., 1996; Reigber et al., 2001; Yang et al., 2008). The Kuqa and southern Junggar FTBs are developed at its southern and northern flanks, respectively, where active thrusting and folding are pronounced (Charreau et al., 2020; Deng et al., 1996; Hubert‐Ferrari et al., 2007; Li, Rao, et al., 2020; Lu et al., 2019; Saint‐Carlier et al., 2016; Tang et al., 2017; Tapponnier & Molnar, 1979). In the northern piedmont, the 1906 M 8 Manas earthquake occurred along the HMT structural belt, where co‐seismic surface ruptures were found in the field (Figure 1b; Avouac et al., 1993; Deng et al., 1996; Stockmeyer et al., 2014), and the occurrence of the 2016 M 6.2 Hutubi earthquake reflects its associated recent seismicity (Li et al., 2018, 2021; Lu et al., 2018).…”

The controls on the thermal evolution of continental mountain ranges

“…In other cases, and on the l h = 300 km graph, the crustal thicknesses used are the maximum observed values. The mountain ranges are (1) northwest Zagros (Khorrami et al., 2019; Motaghi et al., 2017); (2) southeast Zagros (Khorrami et al., 2019; Paul et al., 2006); (3) eastern Greater Caucasus (Gok et al., 2011; Khorrami et al., 2019); (4) western Greater Caucasus (Gok et al., 2011; Khorrami et al., 2019); (5) Kopeh Dagh (Khorrami et al., 2019; Motaghi et al., 2012); (6) Alborz (Khorrami et al., 2019; Radjaee et al., 2010); (7) Peruvian Sub‐Andes (Ryan et al., 2016; Villegas‐Lanza et al., 2016); (8) Bolivian Sub‐Andes (Ryan et al., 2016; Weiss et al., 2016); (9) Columbian Eastern Cordillera (Mora‐Paez et al., 2019; Poveda et al., 2015); (10) The Dinarides (Metois et al., 2015; Stipcevic et al., 2020); (11) western Tien Shan (Vinnik et al., 2004; Zubovich et al., 2010); (12) eastern Tien Shan (Li et al., 2020; Lu et al., 2019; Zheng et al., 2017); (13) Longmen Shan (Tian et al., 2020; Zheng et al., 2017); (14) northeast Pamir (Li et al., 2012; Schneider et al., 2019); (15) western Pamir/Hindu Kush (Ischuk et al., 2013; Schneider et al., 2019); (16) northern Tibet (Tarim margin) (Priestley et al., 2008; Zheng et al., 2017); (17) Qilian Shan (Tian et al., 2014; Zhang et al., 2004); (18) Nepal Himalaya (Priestley et al., 2019; Stevens & Avouac, 2015); (19) Garwal‐Kumoan Himalaya (Priestley et al., 2019; Stevens & Avouac, 2015); (20) Pakistan Himalaya (Priestley et al., 2019; Stevens & Avouac, 2015)…”

Active tectonics and palaeo‐environmental change in West China ‐ Preface

“…Li et al (2020) suggested a spatial variability of modern tectonic stress fields in the northeast margin of the Tibetan Plateau. Focal mechanism solutions and the depths of 54 earthquakes from 2009 to 2017 were obtained from broadband seismic waveforms.…”