Identification of two-phased late Paleoproterozoic magmatism in the Wuyishan Domain (SE China): Implications for the tectonic evolution of the Cathaysia Block

Abstract

The Cathaysia Block amalgamated with the Yangtze Block along the Jiangnan orogenic belt to form the South China Craton during early Neoproterozoic time. However, the origin of the Cathaysia Block and its position in the Nuna supercontinent remain controversial. This paper synthesizes geochronological, geochemical and isotopic data from late Paleoproterozoic igneous rocks in the Wuyishan Domain of the Cathaysia Block (SE China). Two-phases of late Paleoproterozoic A- and S-type granitoids were identified and dated at 1925–1848 Ma and 1816–1750 Ma. The A-type granites in the Wuyishan Domain were likely derived from partial melting of mafic lower crust with a tonalitic to granodioritic geochemical composition, and the S-type granites were derived from partial melting of a meta-sedimentary source. These late Paleoproterozoic granitoids were emplaced in a continental arc/back-arc setting and the two-phased arc/back-arc magmatism was related to the assembly of the Paleoproterozoic Nuna supercontinent. Combining our results with previous late Paleoproterozoic geochemical and age data, we suggest that the Cathaysia Block was located close to northern India Shield during Proterozoic time until the breakup of the Rodinia Supercontinent in the late Neoproterozoic.