The South China and Indochina neighborhood in the assembled Gondwana

Investigations on the late Neoproterozoic to early Paleozoic sedimentary strata of western South China and northern Indochina reveal a provenance affinity between the two, which was mainly derived from the local western part of South China. The newly discovered provenance featured differently from that of the typical Indian-Australian Gondwana siliciclastic source. Basin types and sedimentation histories of the two sedimentary basins in western South China and northern Indochina are also comparable. Furthermore, previous studies discovered the geochronological, petrological and geochemical similarities of the early Paleozoic magmatic rocks between these two regions, suggesting a connection between the two during the subduction of the proto-Tethys ocean towards the northern Gondwana and the accretion of Asian continents onto the Gondwana mainland. Utilizing all such geological information, we speculate in this study that South China and Indochina were probably in the neighbourhood on the northern Gondwana margin when the Gondwana semi-supercontinent was assembled. Specifically, Indochina was likely located to the southwest of South China during the late Neoproterozoic to early Paleozoic. Apart from sedimentation, neither Indochina nor the western part of South China got much deformational and metamorphic impaction from the collision between South China and northern Gondwana during that time.