Characterization of unique natural gas flow in fracture-vuggy carbonate reservoir: A case study on Dengying carbonate reservoir in China

• Published in: Journal of petroleum science & engineering 2019-11, Vol.182, p.106243, Article 106243
• Main Authors: Xie, Xinhui, Lu, Hongjiang, Deng, Hucheng, Yang, Hongzhi, Teng, Bailu, Li, Huazhou Andy
• Format: Article
• Language: English
• Subjects: Fracture-vuggy carbonate reservoir; Natural gas flow; Permeability anisotropy; Stokes-Brinkman equation
• ISSN: 0920-4105; 1873-4715
• DOI: 10.1016/j.petrol.2019.106243

We investigate the natural gas flow behavior in the Dengying carbonate reservoir of Gaoshiti-Moxi Block in China. Outcrops observation, petrophysical properties measurement, and formation micro-resistivity image logging (FMI) all show that the vugs distribute in a stratified manner with characteristic length ranging from 0.2 to 4 cm. The horizontal permeability is significantly larger than the vertical permeability due to the stratified distribution of vugs and fractures. We build a representative conceptual reservoir model to describe this fracture-vuggy type carbonate reservoir. Both Darcy equation and Stokes-Brinkman equation are applied to simulate natural gas flow in this type of reservoir. Simulation results show that natural gas mainly flows along the free channel formed by low-dip fractures and flat ellipsoid vugs. Compared with the Darcy method, the Stokes-Brinkman method provides a more accurate prediction of gas flow behavior in the fracture-vug carbonate reservoir. [Display omitted] •Conduct a systematic study to investigate the natural gas flow in fractured carbonate reservoir of GST-MX Block (China).•Vugs distribute in a stratified manner with characteristic length ranging from 0.2 to 4 cm.•Stokes-Brinkman equation provides a reliable prediction of gas flow behavior in the fracture-vug carbonate reservoir.