关键词: 非均匀布孔, 支撑剂铺置, 砂砾岩油藏, 低成本开采

Abstract: The reservoir of Triassic Karamay Formation in well block X was developed by vertical well water injection in the early stage. As a result，the injection effect was insignificant，the production declined fast，and the overall recovery factor was low. In order to fully produce the remaining oil resources in the block，the original development mode was changed to horizontal well volume fracturing in 2018. The first well executed in 2019 was subjected to annulus fracturing using coiled tubing with a bottom packer，and the initial production of single well after fracturing was increased by 11.5 times compared with that of a vertical well. That validated the feasibility of increasing the production of horizontal wells. In order to satisfy market demands，field tests have been carried out in this block since 2020. Annulus fracturing using coiled tubing hydraulic jet has been gradually substituted by staged fracturing with bridge plug perforating，and the fracturing fluid has been changed from guar gum gel to guar gum slick water. A set of low-cost volume fracturing technologies has been developed. The application results show that: ①the 13 horizontal wells put into production using different technologies have all achieved design productivity; ②uneven fracture initiation can be improved by using bridge plug staged perforating + uneven distribution of perforations; ③insufficient sand-carrying capacity of guar gum slick water can be made up for by increasing the injection rate to ensure safe sand filling during field treatment; ④low-cost volume fracturing technology can reduce the fracturing cost by nearly 30%.

Key words: uneven distribution of perforations, proppant placement, conglomerate reservoir; low-cost exploitation