Abstract:The Kate- Kipili volcano- plutonic complex is located at the junction of the western margin of the Ubendian belt and the Bangweulu block,and is generallyconsidered to represent post- orogenic magmatism of the Ubendian orogeny. The LA- ICP- MS zircon U- Pb dating of three samples has yielded weighted mean 207 Pb/ 206 Pb ages of 1887. 00±8. 6 Ma,1885. 4±8. 0 Ma and 1869. 0±8. 0 Ma,respectively, indicating that they were formed during the late Paleoproterozoic. The whole rock major and trace elements analyses show that these dacite- rhyolites are generally characterized by high silica and are alkali- rich,with low contents of TiO 2, TFeO, MgO and P 2O 5, belong to metaluminous- weakly peraluminous and high potassium calc- alkaline rock series. All the samples are enriched in LREEs and large ion lithophile elements(e. g. , Rb,Th and K),with moderate negative Eu anomaly,while depleted in high field strength elements(e. g. , Nb,Ta,P and Ti),as well as the contents of Ba and Sr vary widely. The dacite- rhyolites inthis study have a high differentiation index (DI=94~98), low aluminum saturation index (A/CNK=0. 82~1. 10) and corundum (<1. 0%). In addition, the phenocrysts from the Kipili volcanics are commonly composed of biotite (chloritized), quartz and feldspar, but aluminum- rich mineralsare absent, suggesting that they are of highly differentiated I- type series. A wide range of zircon ε Hf (t) values (-5. 42~+2. 16),both negative and positive whole rock ε Nd (t) values, high zirconium saturation temperature, as well as two- stage Hf- Nd model ages between early Paleoproterozoic and Neoarchean (2. 26~2. 86 Ga), reveal that these felsic volcanics were derived from partially melted ancient lower crustal rocks which were heated by the underplating of mantle- derived magma, simultaneously with a significant contribution of mantle- derived materials, and then underwent a high degree fractional crystallization. The present results combined with the previous researches in the region, demonstrate that the Kipili volcanic rocks probably erupted during the transition period from syn- collision to post- collision in the Ubendian orogeny.