Prestack inversion identification of organic reef gas reservoirs of Permian Changxing Formation in Damaoping area, Sichuan Basin, SW China

ZHOU Lu,ZHONG Feiyan,YAN Jiachen,ZHONG Kexiu,WU Yong,XU Xihui,LU Peng,ZHANG Wenji,LIU Yi

Table 2 AVO types of Changxing Formation reef reservoirs in the study area and yield of typical wells.

AVO Type Property of fluid in the reservoir Reservoir parameter AVO forward gather of reservoir top boundary and trend analysis Typical wells and production Well name Gas production (104m3•d-1) Water production (m3•d-1) Type Ⅲ Gas layer $\rho ={{2.65}_{{}}} \text{g}/\text{c}{{\text{m}}^{3}} $ $ {{v}_{\text{p}}}=6\ {{044}_{{}}} \text{m}/\text{s} $ $ {{v}_{\text{s}}}=3\ {{400}_{{}}} \text{m}/\text{s} $ $ \phi =6\% $ $ {{S}_{\text{w}}}=5\% $ Yun’anX8 85.49 - Type Ⅳ Gas layer $\rho ={{2.63}_{{}}} \text{g}/\text{c}{{\text{m}}^{3}} $ $ {{v}_{\text{p}}}={{6}_{{}}}{{019}_{{}}} \text{m}/\text{s} $ $ {{v}_{\text{s}}}={{3}_{{}}}{{266}_{{}}} \text{m}/\text{s} $ $ \phi =10\% $ $ {{S}_{\text{w}}}=5\% $ Yun’an6 82 - Yun’anX7 127.13 - Yun’an012_12 43.1 - Gas-bearing water layer $\rho ={{2.71}_{{}}} \text{g}/\text{c}{{\text{m}}^{3}} $ $ {{v}_{\text{p}}}={{6}_{{}}}{{178}_{{}}} \text{m}/\text{s} $ $ {{v}_{\text{s}}}={{3}^{{}}}321_{{}}^{{}} \text{m}/\text{s} $ $ \phi =5\% $ $ {{S}_{\text{w}}}=70\% $ Yun’anX9 2.45 10.08