Geological conditions, reservoir evolution and favorable exploration directions of marine ultra-deep oil and gas in China

LI Jianzhong,TAO Xiaowan,BAI Bin,HUANG Shipeng,JIANG Qingchun,ZHAO Zhenyu,CHEN Yanyan,MA Debo,ZHANG Liping,LI Ningxi,SONG Wei

Table 1 Basic geological parameters of the marine ultra-deep oil and gas fields in China.

Basin Oil and gas field Buried depth/ m Superimposed oil- and gas- bearing area/km2 Proven crude oil reserves/ 104 t Proven natural gas reserves/ 108 m3 Reservoir types Primary oil and gas layers Reservoir lithologies Effective thickness of reservoir/m Poro- sity/% Storage space Structural location Tarim Halahatang 5900- 7600 1 323 24 675 393 Lithologic-stratigraphic O2yj O1-2y Sparite calcarenite, oolitic limestone 6-25 1.8- 21.3/7.5 Cave, vug, fracture Periphery of Manxi intra- cratonic rift Central Tarim No.1 4500- 6800 288 21 983 3 680 O3l O1-2y Sparite calcarenite, reef shoal limestone 5-65 1.8- 16.0/4.6 Tahe 5300- 7000 2410 136 389 384 O1-2y O2yj Sparite calcarenite, oolitic limestone 8-60 2.7- 75.0 Shunbei 7300- 8500 47 9903 216 O1-2y O2yj Sparite calcarenite 3-30 2.6- 36.0 Sichuan Anyue 4500- 5400 2691 3185 11 709 Structural-lithologic ?C1l Z2d Algae dolomite, granular dolomite 5-60 30-280 2.0- 18.5/4.8 2.0- 7.8/3.4 Cave, vug, fracture Periphery of Deyang-Anyue intracratonic rift Longgang 3680- 7286 156 742 P3ch T1f Sparry oolitic dolomite 6-35 3.7- 8.5/6.5 Pore Periphery of Kaijiang- Liangping Trough Puguang 4776- 7100 124 4 121 P3ch T1f 101-411 2.0- 28.9/8.1 Pore Yuanba 6250- 7367 549 2 712 P3ch T1f 40-100 2.0- 23.6/5.2 Pore