1�� College of Earth Sciences��Jilin University��Changchun 130061��China; 2�� Geological Exploration Technology Institute of Jiangsu Province��Nanjing 210049��China

Zircon U- Pb age�� whole rock geochemical and zircon Hf isotopic data are presented for Late Paleozo- ic granodiorites from the Taerqi region��central Daxing'anling to constrain its petrogenesis and tectonic implica- tion�� LA- ICP- MS zircon U- Pb age data indicates that the Late Paleozoic granodiorites were emplaced with age of 333.4 ± 2.2 Ma (Early Carboniferous)�� Geochemically��the granodiorite samples have SiO₂ = 60.54%-71.40%��Na₂O =4.04%- 4.66%�� K₂O = 1.65%- 4.27% and MgO =0.96%-3.53%�� belonging to medium- K to high- K calc- alkaline I- type granites�� They are slightly enriched in large ion lithophile elements (e.g. ��b��Th�� U and K) and light rare earth elements��and depleted in high field strength elements (e.g. Nb��Ta and Ti)�� with ε Hf (t) values of 8.0- 11.8 and Hf two- stage model ages of 586- 829 Ma�� All these geochemical features suggest that the primary magma was derived from partial melting of Neoproterozoic to Phanerozoic newly accreted lower crust�� According to the geochemical data and regional geological investigations��the Early Carboniferous granodiorites formed in an island arc setting linked to the subduction of the Paleo- Asian Oceanic Plate beneath the Xing'an Terrane�� This also implies that the Xing'an and Songliao terranes have not amalgamated before the Early Carboniferous��