LA-ICP-MS U-Pb dating of detrital zircon from the mesozoic sandstone core-samples in well DB1 of Northeast Junggar Basin

Three groups of sandstone samples in ages ranging from the Late Triassic to Mid-Late Jurassic were collected from the Dbl well in the northern Jungger Basin.The U-Pb ages of 237 single zircon grains contained in the sandstone samples were anslyzed by the LA-ICP-MS method.According to the mineralogical characteristics,zircon cathodoluminescence image and the age distribution characteristics,combined with the constraints of palaeocurrent,the sediment sources and geological significance were discussed.It is shown that the main source for detrital zircon in Junggar Basin might include an internal and quasi north peripheral orogenic belt.Detrital zircon U-Pb ages were in a wild range of 150～1 224 Ma,and four major age groups,i.e. 538～360 Ma,354～271 Ma,267～208 Ma,185～150 Ma had existed,corresponding to seven major peak age at 510,490,410,330,290,250,162 Ma.Detrital zircons had a peak age 162 Ma,implying that the Yanshanian movement had affected the tectonic evolution in the northern Jungger Basin.