TECHNICAL DIFFICULTIES AND COUNTERMEASURES IN COMPLEX GAS RESERVOIRS' EXPLORATION AND DEVELOPMENT

West-East Gas Pipeline completed during the tenth Five-Year Period provoked the growth of Chinese gas industry significantly and stimulated the enthusiasm of development of upstream, middle stream and downstream of natural gas industry. Based on the analysis of gas resources distribution and geological conditions, many technical difficulties still hold back the rapid growth of gas exploration and development engineering, in particular, those difficulties unsettled even in the world exist in developing special types of gas reservoirs including ultra deep reservoir tight gas reservoir and H2S or CO2 rich gas reservoirs. This paper presents systematic analysis of existing problems from angle of seismic prospecting, drilling, reservoir study, stimulation technology, wellbore technology and surface engineering technology and proposes key aspects of future scientific and technical research, which is promoting use of mature technology, introducing advance technology, endeavoring to make breakthrough of technical bottleneck and innovating special technology. The paper also suggests key research objects and technologies and sets the technical route for overall improvement of China's complex gas reservoir exploration and development and, and for promotion of China's natural gas production.