Detrital zircon U-Pb chronology and geological significance of the Middle Jurassic Quesang Hot Spring Formation in Linzhou Basin, Tibet

The Linzhou Basin is located in the middle of the Gangdese Plate. Basin analysis of the Linzhou Basin will provide important sedimentological evidence for understanding the tectonic evolution process of the Gangdese Plate. This paper takes the Middle Jurassic Quesang Hot Spring Formation in the Linzhou Basin as the research object, and conducted petrology and detrital zircon U-Pb chronology. The results show that the youngest detrital zircon age of the lithic quartz sandstone of the Quesang Hot Spring Formation is 169 Ma, with age peaks such as 170-200 Ma, 540-620 Ma, and 1055-1220 Ma. The youngest detrital zircon age is the response to a magmatic event triggered by the subduction of the Tethys oceanic crust. Regional comparative studies of detrital zircons show that the source of the Quesang Hot Spring Formation is mainly from the Tanga-Songduo orogenic belt in central Gangdese, which is a sedimentary record of the northward subduction and southward accretion of the Tethys Ocean.