Study on high production factors of high-pressure shale gas from Haynesville Shale Gas development data

The actual production data from Haynesville Shale gas wells show that, the three leading factors affecting production are geologic sweet spot area, fracture parameters and proper drainage. The key factors for sweet spot areas selection in shale include reservoir thickness (50 to 60 m), total organic carbon (TOC) (3%), porosity (4%), pressure coefficient (2.0), and the content of brittle minerals (60%). The fracturing parameters for reservoirs with high-production horizontal wells are: the length of horizontal section being generally 1 000 m to 1 500 m; stages being in 9 to 12; the length of single stage being 90 m to 110 m; cluster spacing being 20 to 25 m; construction displacement being 11 to 13 m3/min; fluid volume for single stage being greater than 1 500 m3; and sand volume for single stage being greater than 120 t. Maintaining a small initial production pressure differential helps maintain the seepage capacity, and hence obtain the maximum cumulative production. It is recommended that using the similar experiences from North America for reference, optimizing the fracturing parameters according to geologic features of shales in different blocks, and realizing economic and efficient development of shale gas.