Reservoir Evaluation and Development ›› 2022, Vol. 12 ›› Issue (1): 95-106.doi: 10.13809/j.cnki.cn32-1825/te.2022.01.008

• Shale Gas • Previous Articles     Next Articles

Sedimentary characteristics and geological significance of outcrop in Wufeng-Longmaxi Formation, Huangying Town, Wulong District, Chongqing

HE Xipeng(),GAO Yuqiao,MA Jun,ZHANG Peixian,HE Guisong,ZHOU Dina,LIU Nana,SUN Bin   

  1. Sinopec East China Oil & Gas Company, Nanjing, Jiangsu 210019, China
  • Received:2021-10-10 Online:2022-02-26 Published:2022-03-24

Abstract:

At present, the Wufeng-Longmaxi Marine high quality shale is the only case that has been commercially exploited in China. Taking Huangying section in Wulong District, Chongqing as an example, the characteristics of sedimentary geochemistry and their interrelationship of Marine high quality shale are studied by the field observation and field measurement combined with laboratory experiment analysis. The results show that: firstly, the black siliceous shales of Wufeng Formation and dark gray shell argillaceous limestone of Guanyinqiao Formation are exposed from bottom to top in Huangying section, which reflects the sedimentary environment from deep water shelf to shallow sea and then to deep water shelf. Secondly, the biostratigraphy of outcrop layer is continuous and intact, and the Kaidian-Rudan WF2-LM5 graptolite zone can be recognized. The graptolite type, content and preservation characteristics are closely related to the sedimentary environment. Thirdly, the Wulong area is located in the hydrocarbon generation center of the deepwater shelf. The high-quality shale has large thickness, superior static index, high hydrocarbon generation intensity and good material basis for shale gas enrichment. Fourthly, Wulong area is the sweet spot of both shale gas exploration and development because of the good accumulation and enrichment conditions of shale gas in small layer ①—④.

Key words: high quality shale, sedimentary environment, shale gas, Longmaxi-Wufeng Formation, Huangying section of Wulong

CLC Number: 

  • TE122