1.2. Geological background of the South China Block
The SCB is composed of the Cathaysia and Yangtze Blocks, which are
assembled along the Jiujiang-Shitai fault (He et al., 2013). The SCB was
formed by collision of the Yangtze and Cathaysia subblocks at
approximately 0.8–1 Ga along the Jiangnan orogen or the Jiujiang-Shitai
fault, which shaped its fundamental tectonic architecture (Yao et al.,
2011; He et al., 2013) (Fig. 1a, blue rectangular region; Fig. 1c).
Following this event, the SCB further docked with the NCC to the north
along the Qinling–Tongbai–Hong’an–Dabie–Sulu orogenic belt, to the
west along the Longmenshan fault and to the southwest along the
Ailaoshan-Song Ma orogen with the Indochina Block in the Triassic (Zheng
et al., 2013).
The SCB basement is dominantly composed of Paleoproterozoic,
Mesoproterozoic and early Neoproterozoic rocks (Zhao and Zheng, 2009)
that were involved in and overprinted by at least three tectonic events,
namely, the Caledonian in the early Palaeozoic, Indosinian in the
Triassic and Yanshanian during the Jurassic-Cretaceous (e.g., Charvet,
2013), which might have led to the inhomogeneous rejuvenation of ancient
crustal and lithospheric structures (e.g., Li et al., 2012).
Concurrently, the SCB retains the imprints of several metallogenic and
tectonothermal events that correspond to global supercontinental cycles
and tectonic activity and is one of the major polymetallic provinces in
the world.