Carboniferous tuff in the Di’nan uplift widely developed at the southern edge of the Luliang Uplift in JunggarBasin. This paper fully reports the Carboniferous tuff from Well Dixi-14 about the study of zircon SHRIMP U-Pb dating, geochemistry and tectonic environment. Combined with analysis from SHRIMP zircon U-Pb ages of volcanic rocks and the regional geological setting, the authors consider that the Ludong area was still in the subduction-related environment in Early Carboniferous, and the closure time of Kalameili ocean basin was no earlier than 337.2 Ma. In addition, no old zircon has been discovered from these studied samples, suggesting that there may not exist the Precambrian basement in the JunggarBasin.