Fig. 1. The six types of olivine fabrics and slip systems (Jung & Karato, 2001; Holtzman et al., 2003; Couvy et al., 2004; Kateyama et al., 2004; Jung et al., 2009a, 2009b; Ohuchi et al., 2011; Michibayashi et al., 2016) shown on lower-hemisphere equal-area projections. X is parallel to the lineation; Y is normal to the lineation and parallel to the foliation; Z is normal to the foliation. The arrows and pink lines in the right-hand column represent the sliding direction and slip plane, respectively.
2 Geological setting
The Altyn Tagh orogen is located along the northern margin of the Qinghai–Tibet Plateau, and is situated between the Tarim Block to the north, and the Qaidam Block and Qilian and Kunlun orogenic belts to the south (Fig. 2a; Wang et al., 2011). Based on structural, geochemical, and geochronological data, the Altyn Tagh orogen can be divided into four units from north to south (Fig. 2b): (1) the Archean North Altyn Terrane, which comprises mainly the granulite-facies Milan Complex and overlying Annanba Group; (2) the Hongliugou–Lapeiquan subduction–collision complex, which includes early Paleozoic ophiolites, pelagic and clastic sedimentary rocks, and HP–LT blueschists and eclogites; (3) the Milanhe–Jinyanshan block, which consists mainly of Meso–Neoproterozoic low-grade metamorphic rocks, schists, limestones, sandstones, mudstones, and thick stromatolites; and (4) the South Altyn subduction–collision complex, which can be further divided into the Jianggalesayi–Danshuiquan–Yinggelisayi HP-UHP metamorphic belt and Apa–Mangya ophiolite complex (Liu et al., 2002, 2012, 2015, 2018; Zhang et al., 2005, 2014; Wang et al., 2011; Gai et al., 2022).