Productivity Characteristics of Hydraulic Fracturing Tight Gas Wells and Main Controlling Factors of High Production Wells

Affected by depositional conditions, the M gas field has large reservoir thickness changes, rapid phase changes, and complex sand body superimposition patterns. There is no strict positive correlation between effective thickness and sandstone thickness, and the reservoir is low porosity and ultra-low permeability lithology Gas reservoir. The development practice shows that to obtain high productivity of a gas well not only needs to be located in a favorable geological “sweet spot”, but also requires a reasonable volume of reservoir stimulation, to realize the effective production of controlled reserves. The influence of gas well productivity mainly includes geological factors and engineering factors. Among them, physical properties such as reservoir thickness, gas content, porosity, and permeability are the basic factors controlling gas well productivity; the low-velocity non-Darcy effect of fluid in matrix flow, the high-speed non-Darcy effect in fracture flow, and the stress-sensitivity effect of fracture permeability is the mechanistic factor affecting gas well productivity; the length of horizontal section, hydraulic fracture length, natural fracture development degree, sand addition amount, ceramsite displacement, and sand ratio are engineering factors affecting gas well productivity. To obtain high productivity, a gas well must be in a favorable sedimentary facies zone geologically, have good physical properties and gas-bearing properties, and have relatively high formation pressure. At the same time, it is necessary to adopt reasonable reservoir stimulation methods in engineering to maximize the production of geological reserves.