International Open Access Journal Platform

Discussion on the Staggered-Layer and Alternate-Round Development Model for Shale Gas Wells in the Longmaxi Formation of the Luzhou Block

Environment and Resource / 2025,7(2):  / 2025-12-23 6 2

View Download PDF

• Authors: Zhi Gao¹ Jing Li¹ Tao Chen² Tian Tang¹ Cheng Yang¹
• Information:

  1. Institute of Geological Exploration and Development of CNPC Chuanqing Drilling Engineering Company Limited, Chengdu;
  2. Sichuan Yuesheng Energy Group of CNPC Chuanqing Drilling Engineering Company Limited, Chengdu

• Keywords:
  Luzhou Block; Shale gas; Casing deformation; Fracture interference; Alternate-round implementation; Staggered-layer development
• Abstract: The high-quality reservoir in the Longmaxi Formation of the Luzhou Block in southern Sichuan is characterized by planar stability, continuity, significant vertical thickness, and developed natural fractures. A rational, well-pattern deployment model is crucial for preventing casing deformation and fracture interference between shale gas wells, as well as enhancing gas well productivity. Based on static reservoir characteristics and production performance of the Longmaxi Formation shale in the study area, along with actual drilling data, this study analyzes the staggered-layer and alternate-round development model for the Longyi₁ sub-layer in the main production area of the northern Luzhou Block. The model features a well spacing of 300–400 m horizontally, with staggered development in the vertical layers of Longyi₁ and the upper-middle section of Longyi₁, implemented and put into production in alternating rounds. Statistical results from the study area demonstrate that this development model effectively mitigates engineering complexities, reduces the casing deformation rate, and increases the average estimated ultimate recovery (EUR) per kilometer per well by 10% compared to conventional deployment methods.
• DOI: (DOI application in progress)
• Cite: Gong, X., Li, J., Luo, A., He, J., Liu, X., Cao, W., Su, H. Z. Ren,X.H, Yang,Z.N. (2025). Well logging prediction of total organic carbon content in shale gas reservoirs of the Long 11 submember in southern Sichuan — Taking the Z205 Well Area as an Example. Environment and Resource, 7(2)