| Author's Name: XU Zhengyu, LIANG Xing, LU Huili ,CHEN Wei, ZHANG Jiehui,SHU Honglin,WANG Gaocheng, XU Yunjun, TANG Xiehua |
| Based on the shale depositional background and environment, structural reformation process, reservoir filling
characteristics and records of Wufeng Formation-Longmaxi Formation in Zhaotong Demonstration Area, combined with
the analysis of shale hydrocarbon generation history, it is clear that the distribution of shale gas favorable area in the
demonstration area is mainly controlled by three factors: sedimentary facies, deformation strength during the reformation
period and sealing performance during the preservation period. According to the current shale gas preservation unit, shale
gas reservoirs in the demonstration area are divided into three types: anticline, syncline and slope. The anticline type
(Taiyang, Haiba, etc.) is mainly enriched in crude oil-cracked gas, and the main controlling factors are the strength of later
transformation and the sealing performance of the preservation unit, and the favorable areas are mainly isolated and
inherited anticlines. The syncline type (Luochang-Jianwu, Luobu, etc.) is mainly enriched with kerogen pyrolysis gas, and
the main controlling factors are sedimentary facies and the sealing performance of preservation units, and the favorable
areas are mainly wide and gentle inherited synclines, most of which are continuously distributed. The slope type
(Huangjinba-Zijinba zone of the south wing of Luochang-Jianwu compound syncline and Yunshanba transition area
between Taiyang and Haiba anticline, etc.) is characterized by enrichment of mixed source gas (crude oil-cracked gas and
kerogen pyrolysis gas), and the favorable areas are mostly distributed along the wing transitional zone between anticline
and syncline |
