Abstract: In order to clarify the characteristics and exploration and development potential of shale reservoirs in Longyi₁⁴ Sub-bed, Longmaxi Formation, Luzhou Block and to realize the longitudinal three-dimensional development of the shale reservoirs in Longmaxi Formation, Southern Sichuan, Longyi₁⁴ Sub-bed is divided into three single horizons: a, b and c, and their characteristics are analyzed, including shale thickness, organic matter abundance, mineral composition, physical characteristics, reservoir pace type and hydrocarbon showing. The result shows: Class I reservoir of Longyi₁⁴ Sub-bed in Luzhou Block is featured by an average thickness of 35.6 m, a distribution area of about 1 900 km² and geological resources of more than 8 000×10⁸m³, indicating bright prospects for exploration and development. The shale reservoir at Horizon b is of a thickness of greater than 20 m, an average TOC is greater than 2.5%, a content of brittle minerals of greater than 55%, an average porosity of 4.9%, and an average gas content of 4.5 m³/t, which demonstrates superior reservoir conditions. Compared with the current main pay - Longyi₁¹ Sub-bed, the shale reservoir at Horizon b of Longyi₁⁴ Sub-bed has higher clay content and inorganic pore proportion, which requires scientific fracturing technology and shut-in and drainage measures in the exploitation process to achieve better development results. The results of the study will provide technical support for expanding shale gas exploration and development horizons and improving the production degree of shale gas resources in Longmaxi Formation, Luzhou Block.

Key words: Shale gas, Longmaxi Formation, three-dimensional development, exploration and development potential, Luzhou Block