Synchronous injection-production energy replenishment for a horizontal well in an ultra-low permeability sandstone reservoir: A case study of Changqing oilfield in Ordos Basin, NW China

WANG Jing,LIU Jungang,LI Zhaoguo,LI Hongchang,ZHANG Jiaosheng,LI Wenqing,ZHANG Yuanli,PING Yi,YANG Huanying,WANG Ping

Table 5 Formation breakdown pressure and inflection point pressure of Well CP14-01 (well depth 2210 m).

Artificial fracture No. Formation breakdown pressure/MPa Converted formation breakdown pressure range/MPa Converted wellhead water injection pressure/MPa Inflection point pressure on water absorption curve/MPa ① 43.0 32.3-38.7 10.15-16.60 12.0 ② 57.0 42.8-51.3 20.65-29.20 ③ 47.0 35.3-42.3 13.15-20.20 ④ 36.0 27.0-32.4 4.90-10.30 ⑤ 47.5 35.6-42.8 13.52-20.65 ⑥ 46.6 35.0-41.9 12.85-19.84 ⑦ 51.0 38.3-45.9 16.15-23.80 ⑧ 51.0 38.3-45.9 16.15-23.80