Abstract:Located in the western Central Qilian Mountain, the Wuergelate pluton is mainly composed of granodiorite and monzonitic granite. In this paper, the authors studied its zircon LA-ICPMS U-Pb age and major and trace elements. The results show that the zircon 206Pb/238U weighted average age is 490.5±1.4 Ma (MSWD=0.85), indicating that the pluton was formed in the Late Cambrian. Compositionally, SiO2 values range from 65.10% to 71.21%, Al2O3 from 14.94% to 16.82%, MgO from 0.23% to 1.24%, A/NKC from 0.9 to 1.0, and Na2O/K2O from 1.01 to 2.33, suggesting metaluminous rocks. In addition, the rocks are enriched in LILE(Ba, U, Sr) and LREE, and depleted in HREE and HFSE (Nb, Ta, Ti and P). The Sr values range from 345×10-6 to 541×10-6, averaging 402×10-6, Yb from 0.72×10-6 to 1.19×10-6, averaging 0.97×10-6, and Y from 6.09×10-6 to 11.30×10-6, averaging 8.67×10-6, with no negative Eu anomalies (δEu=0.91~1.27). The geochemical characteristics imply that the Wuergelate pluton could represent adakite, and was formed in a subduction orogenic setting. Combined with the tectonic location of the granite and regional geology, the authors hold that the North Qilian oceanic plate subducted southward under the Central Qilian blocks in the late Cambrian, which resulted in the formation of Wuergelate pluton.