Types and resource potential of continental shale oil in China and its boundary with tight oil

ZHAO Wenzhi,HU Suyun,HOU Lianhua,YANG Tao,LI Xin,GUO Bincheng,YANG Zhi

Table 1 Comparison of geological conditions and economics of marine and continental shale oil of medium-high maturity.

Shale oil type Main basin Source condition Reservoir condition Mobility Economics TOC/% Matu- rity/% Lithology Thick- ness/m Poro- sity/% Crude oil density/ (g•cm-3) Pressure coefficient Oil-gas ratio/ (m3•m-3) Burial depth/m Cumulative production per well/ 104 t Marine facies Bakken Formation in Williston Basin 10.0-20.0 0.7-1.3 Siltstone, Dolomitic sandstone, dolomite 20-50 5.0-12.0 0.78-0.83 1.3-1.6 50-375 2 100-3 300 4.1 Eagle Ford Formation in Mexico Gulf Basin 4.0-7.0 0.5-2.0 Shale, argillaceous rock 46-92 6.0-12.0 0.77-0.79 1.3-1.8 90-850 1 000-3 400 4.3 Wolfcape Formation in Permain Basin 2.0-5.0 0.6-1.5 Siltstone, argillaceous rock 40-135, >400 8.0-12.0 0.77-0.79 1.5 >350 2 200-3 300 6.5-8.6 Conti- nental facies Permian in Junggar Basin 3.0-6.0 0.6-1.1 Dolomitic siltstone, argillaceous dolomite 4-33 6.0-14.0 0.89-0.93 1.1-1.3 17 2 300-3 800, 3 800-4 300 3.5*, 3.8-4.2* Permian in Santanghu Basin 1.0-5.0 0.6-1.3 Tuff, tuffaceous dolomite 27-43 6.0-19.0 0.86-0.91 1.0-1.2 0 1 800-3 700 1.6* Kongdian Formation and Shahejie Formation in Bohai Bay Basin 1.5-3.5 0.5-1.1 Shale, mudstone, siltstone and fine sandstone, dolomitic and calcareous shale, dolomite 10-26 3.0-7.0 0.86-0.89 1.0-1.2 0-100 2 600-4 200 3.0* Chang 7 Member of Yanchang Formation in Ordos Basin 5.0-38.0 0.7-1.1 Shale, mudstone, siltstone and fine sandstone 2-26 5.0-12.0 0.83-0.88 0.7-0.8 60-120 1 600-2 200 1.4* Cretaceous in Songliao Basin 0.9-3.8 0.5-1.2 Mudstone, shale, siltstone and fine sandstone 1-6 4.0-8.0 0.78-0.87 1.2-1.6 40 1 600-2 500 1.9* Jurassic in Sichuan Basin 1.0-2.4 0.5-1.4 Shale, mudstone, shell limestone 10-50 0.2-7.0 0.76-0.87 1.2-1.7 1 400-4 200 1.4-3.5 Paleogene in Qaidam Basin 0.4-1.2 0.6-1.2 Marl, algal limestone, siltstone 100-150 5.0-8.0 0.85-0.88 1.3-1.4 42-109 2 500-4 000 2.5*