The Darbut ophiolite in West Junggar is covered unconformably by sedimentary-volcanic series of Tailegula Formation in Sartohay region. LA-ICP-MS U-Pb dating on zircons from dacite gives the ~(206)Pb/~(238)U weighted mean age of 349±2 Ma, indicating that the Tailegula Formation was formed in Tournaisian of Early Carboniferous. The dacites show right-oriented linear REE patterns with LREE enrichment and negative Eu anomaly. In trace element primitive mantle normalized diagram, the standardized abundance of a...