DIFFICULTIES AND TECHNICAL MEASURES OF FRACTURING IMPROVEMENT IN XU-4 RESERVOIR OF XINCHANG STRUCTURE

The tight sand gas reservoir in the Xujiahe Formation of Xinchang Structure in western Sichuan basin has characteristics of deep burial,high temperature,unconventional high pressure and great difficulties in fracturing treatment.Through describing the characteristics of Xu-4 reservoir in the well Xin-855,the difficulties of fracturing treatment have been analyzed and specific technical measures,such as adding conventional sand,keeping low ratio of sand,slug flushing,combining proppants with several grain sizes,adding sand linearly and fracturing test,have been developed and achieved relatively good yield results,which show that as long as the sand fracturing technology is used properly,the fracturing treatment gas reservoir of high temperature,high pressure and high demanding can still get an excellent sand fracturing effects.