Early Paleozoic orogenesis along Gondwana's northern margin constrained by provenance data from South China

• Published in: Tectonophysics 2014-12, Vol.636, p.40-51
• Main Authors: Xu, Yajun, Cawood, Peter A., Du, Yuansheng, Huang, Hongwei, Wang, Xinyu
• Format: Article
• Language: English
• Subjects: Age; Boundaries; China; Derivation; Detrital zircon; Early Paleozoic; Gondwana; Himalaya; Himalayas; South China; Spectra; Tectonics; Zircon
• ISSN: 0040-1951; 1879-3266
• DOI: 10.1016/j.tecto.2014.08.022

The Cambrian–Ordovician boundary unconformity in the southern part of the South China Craton is spatially and temporally related to coeval orogenic activity along the Indian margin of east Gondwana. Detrital zircon age spectra from strata above and below the unconformity range in age from 3580–450Ma, with peaks in the late Mesoproterozoic and Neoproterozoic. The patterns are similar to time equivalent sequences elsewhere in South China and together with regional facies relationships and paleocurrent data indicate derivation from a Gondwana source. The disconformity at the base of the Ordovician succession forms part of a regional break that has also been documented in the Himalaya, Qiangtang, Lhasa, Sibumasu, and Western Australia. All these successions have similar detrital zircon age spectra suggesting derivation from common source(s). In South China the effects of this tectonic event are relatively mild and are represented by a local disconformity at the base of the Ordovician succession, but elsewhere in north Gondwana this event is marked by an angular unconformity with metamorphism of older units and relatively widespread magmatic activity. South China was likely located in a distal location to the northeast of the pulse of tectonic activity, which was focused in the Himalaya region, and was close to the continent–ocean boundary between northern Gondwana and the proto-Tethys. [Display omitted] •South China was located along the northernmost margin of East Gondwana.•Early Paleozoic orogenic activity in north Gondwana affected South China.•Detritus from the Himalayan region accumulated in South China.•South China represents the distal portion of the northward facing synorogenic basin.