Analysis on Main Controlling Factors of Fracturing Effect of Fengxi Tight Oil

In Fengxi tight oil field of Qaidam Basin, long horizontal well + close cut volume fracturing is the main technology, which has achieved certain results. However, there are still some problems, such as unclear main controlling factors of oil well productivity and undetermined development technology. Fengxi N21-III-3 has two sets of targets, the upper target is thin layer algal limestone + lamellar limestone, and the lower target is thick layer lamellar limestone. The two sets of targets have their own advantages. FH1 of oil group III encountered the upper and lower target formations with about 81% water cut after production. In 2021, all three horizontal Wells will be put into production in the upper target zone, with water cut of more than 90%. In view of this phenomenon, the post-compaction effect of N21-III-3 layer is analyzed from geological and engineering perspectives, so that the lower target layer is a better sweet spot. According to the analysis of fracturing parameters, it is considered that the fracturing technology is a combination of fist, and the fluid volume, sand volume, displacement and cluster spacing should be guaranteed. However, under the overall cost limitation, the fluid volume of single cluster should be guaranteed first.