“…In summary, the Lower Silurian Tuolie Formation is a thick, bathyal to abyssal facies, continental shelf to slope, clastic turbiditic succession with minor volcanic rocks, tuffites, tuffaceous siltstones, and intercalated limestones, and has similar geochemical compositions to those from a cratonic or recycled-orogen provenance (Bhatia, 1983;McLennan et al, 1990). According to Metcalfe (2011Metcalfe ( , 2013 and others (e.g., Jiang et al, 2003;Su et al, 2009;Usuki et al, 2013;Wang et al, 2014a;Zhou et al, 2014), the SCB was closely related to the evolution of the northeast Gondwana in the early Palaeozoic. The geochemical characteristics and depositional setting of the Early Silurian (meta)siliciclastic rocks in Hainan Island may indicate a special position for the SCB in Gondwana.…”