Geochemical Characteristics and Sedimentary Environments of Siliceous Rocks and Siliceous Mudstone——Case Study of Bayingou Ophiolitic Mélange in Xianjiang

The flaggy cherts and argillite in the ophiolitic mélange of Bayingou have a SiO₂ content of 55.37%-91.19%,a high Al₂O₃ content between 3.07%-17.66%,and a TiO₂ content of 0.12%-0.8%,having a good positive correlation between Al₂O₃ and TiO₂,suggesting that they have a relatively high percentage of terrigenous muddy sediments Moreover,they have typical NASC-normalized flat REE patterns without any visible Cenegative anomaly;and the Eu has an obvious right-hand dipping pattern.