The relationship between Lincang block and provenance of Nanduan Formation:Evidence of detrital zircon U-Pb dating from metasandstone of Devonian-Carboniferous Nanduan Formation

U-Pb ages of detrital zircons of Devonian-Carboniferous Nanduan Formation from Lincang block define three distinctive age peaks in older Grenvillian (1100~1300Ma), younger Grenvillian (900~980Ma) and Pan-African (530~680Ma), and two subordinate group in 1550~1730Ma and 2350~2630Ma, suggesting that the provenance of sediments had multi-source and complex characteristics. The age spectrum is obviously different from detrital zircon age spectrum of the Devonian-Carboniferous sediments of Simao block, which indicates that the sediments of Nanduan Formation came from East Ganwana supercontinent, and the result is indicated by paleobiology which shows a genetic relationship between East Ganwana and paleo-Tethys in southwest Yunnan.