2007 年 72 巻 6 号 p. 541-545
In the Minami Nagaoka gas field located in Niigata Prefecture, Japan, additional perforations were conducted in a hydraulically fractured well to increase the productivity of the well. To our best knowledge, successful additiona lperforation treatments in hydraulically fractured wells have not been reported. A well, Minami Nagaoka MHF-1, was performed six-stages fracturing with limited perforation intervals. Since the production logging data was necessary to perform an efficient perforation job, the production logging was run just before the additional perforations. The additional perforations were conducted at some intervals where gas inflow concentrated to mitigate non-Darcy effects due to the excess gas inflow. Post-job evaluation confirmed that the additional perforations contributed to increase the productivity by a factor of two.