Recognition and spatial pattern of Carboniferous volcanic edifice in Dixi-10 wellblock of Kelameili Gasfield,Junggar Basin

The planar distribution of the volcanic conduit of the Carboniferous volcanic edifice in Dixi-10 wellblock of Kelameili Gasfield,Junggar Basin is recognized by amplitude time slice and coherent time slice. The conduit and the external form of the volcanic edifice are distinguished according to the resistivity section inversed by the electric field sounding and the conventional seismic section.The types of the volcanic lithofacies and their composition relationship are recognized according to core,logging and seismic data,and the eruption sequence of the volcanic edifice is divided. Based on these,the spatial pattern of Carboniferous central volcanic edifice is established. The results show that a central volcanic edifice is recognized in this wellblock. There are 5 types of volcanic lithofacies in this volcanic edifice,and they are volcanic conduit facies,extrusive facies,volcanic sedimentary facies and explosive facies from the center to the outward of the volcanic edifice. The subvolcanic facies formed by hypabyssal intrusive lava has a limited distribution. The volcanic eruption sequence is lava eruption early and volcanic pyroclastic eruption later. The volcanic sedimentary facies is formed in the intermittent period of volcanic eruption.