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).