Provenance and Tectonic Settings of Early Carboniferous Sedimentary Strata in Western Junggar,Xinjiang
Liao Wanlin
Xiao Long
Zhang Lei
Wang Guocan
Abstract：The geochemistry and detrital zircon characteristics of the sediments play an important role in the study of sedimenta-ry provenance and their tectonic settings.This paper presents petrography and geochemical study of the Early Carboniferous Baogutu Group and Tailegula Group clastic rocks in Karamay area,western Junggar,NW Xinjiang.Geochemical data show that the sedimentary rocks have SiO2 contents (54.64%-73.14%),relatively high Al2 O3 contents (11.89%-19.36%)and high (TFe2 O3 +MgO)contents (3.97%-9.99%),indicating low chemical maturity.Their total rare earth element contents vary between 83×10-6 and 252×10-6 ,characterized by no Ce anomaly and slightly negative Eu anomalies,which is similar to those of sandstones formed at oceanic island arc setting.U-Pb dating results of detrital zircons show that Baogutu Group has 340 and 440 Ma two peak values.Detrital zircons of Tailegula Group show only one peak (325 Ma)and suggests that they were sourced from the Early Carboniferous rocks.Discrimination diagrams of the major and trace elements show that the provenance and tectonic settings of Early Carboniferous Baogutu and Tailegula groups sedimentary rocks were formed from the oceanic is-land arc and continental island arc acidic volcanic rocks,with minor mafic volcanic rocks.
Keywords：western JunggurEarly Carboniferousgeochemistry of sedimentary rocktectonic setting
Publication Date：2015-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：19( 485-503 )