| Summary: | Zircon U-Pb dating results indicate that late Neoarchean Badu Complex in the eastern Cathaysia Block, South China, experienced Paleoproterozoic high-grade metamorphism and was intruded by extensive coeval granites with different geochemical features. High-grade metamorphism and S-type granitic magmatism indicate that a Paleoproterozoic collisional orogeny occurred in the Cathaysia Block. Comparisons on geochronological, Hf-Nd isotopic and petrologic data of the Cathaysia with those of other Paleoproterozoic orogens worldwide suggest that the Cathaysia was linked with the South Korean Peninsula and the Lesser Himalaya of NW India in the Columbia supercontinent. Previous chronological data show that there are many Grenville-age detrital zircons in Neoproterozoic sediments in the Cathaysia, suggesting the existence of a Grenvillian orogen in the southern margin of South China. Similarity of age spectra, Hf-isotope compositions and rock associations show the affinity of the Cathaysia with East India-East Antarctic-West Australia (East Gondwana) during the breakup of Rodinia supercontinent. It was thought that Pan-African orogeny was very weak in the Cathaysia Block. However, early Paleozoic sedimentary rocks in the East Cathaysia contain abundant 690-490 Ma detrital zircons, suggesting that the East Cathaysia was close to the Gondwana before early Paleozoic. Therefore, the Cathaysia Block kept long-time linking with East Gondwana from 1.9 Ga to 0.5 Ga.
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