The lower assemblages(the Carboniferous to the Triassic)in the central Junggar Basin have a large burial depth and a low degree of exploration,and the exploration fields and breakthrough directions of oil and gas are not clear. Based on the analysis of the discovered oil and gas reservoirs,the deep geology structure of the basin was clarified,as well as the sedimentary and the eservoir formation conditions,and the types of oil and gas reservoirs and hydrocarbon accumulation conditions in key areas were systematically dissected. Moreover,the favorable exploration fields of the lower assemblages in the central Junggar Basin were predicted,and the deep and ultra-deep oil and gas exploration in the basin was guided. The research results show that many types of reservoir rocks,such as volcanic rocks,conglomerates,and fine sandstones,are developed in the lower assemblages of the central Junggar Basin,and the reservoir’s physical properties are quite different. Under the overall compact background,there are still high-quality reservoirs with relatively good physical properties,and sweet spots are developed in different layers. Still,the development mechanisms of effective reservoirs are different. Based on the source and storage allocation relationships,four types of oil and gas reservoir combinations are formed in the lower assemblages of the central Junggar Basin,which are adjacent-source volcanic buried-hill reservoirs,intra-source and near-source stratigraphic overlap reservoirs in the Fengcheng Formation-Upper Wuerhe Formation,above-source stratigraphic-lithologic reservoirs in the Baikouquan Formation,and far-source lithologic reservoirs in the middle-upper Triassic Formation. The far-source lithologic reservoirs in the middle-upper Triassic Formation are relatively shallow in burial depth,highly enriched,and productive,making them an important field for rapidly increasing reserves and production. Furthermore,the adjacent-source volcanic buried-hill reservoirs and intra-source and near-source stratigraphic overlap reservoirs in the Fengcheng Formation-Upper Wuerhe Formation have large beneficial areas and abundant resources,which are the key fields for seeking major breakthroughs and significant discoveries. Through the comprehensive consideration of the key breakthrough areas for multi-layer exploration,which takes advantage of large-scale resources,multiple layers,and shallow burial,three Class I potential areas(the west and east slopes of Well Pen1 West Sag and the Dongdaohaizi Sag)and two Class II potential areas(the west slope of Fukang Sag and the northeast slope of Shawan Sag)have been selected from the lower assemblage in the central Junggar Basin.