Resource types, formation, distribution and prospects of coal-measure gas

ZOU Caineng,YANG Zhi,HUANG Shipeng,MA Feng,SUN Qinping,LI Fuheng,PAN Songqi,TIAN Wenguang

Table 1 Comparison of geological conditions of coalbed methane in key basins/areas.

Mature interval Basin Geolo- gical age Area/ 104 km2 Resource extent/ 1012 m3 Depth/ m Ro/ % Coal seam thickness/ m Gas content/ (m3?t-1) Perme- ability/ 10-3 μm2 Reservoir pressure coefficient Single well daily gas production/ 104 m3 Gas source type Medium high coal rank San Juan K 1.94 2.38 170-1 200 0.75- 1.20 6-20 8.5- 20.0 1-50 1.36 2 Thermogenic gas, biogenic Gas Black Warrior C 1.55 0.57 140-1 220 1.0-1.9 4.6-7.6 5-18 1-25 Low-normal pressure 0.10-0.90 Thermogenic gas Qinshui C—P 4.20 4.00 0-2 000 Greater than 1.8 1.2-23.6 1-40 Less than 1 Low-normal pressure Vertical well 0.05- 0.80; Horizontal well 0.50-10.00 Thermogenic gas Ordos C—P 4.20 3.19 400-2 000 0.5-2.2 0-30 3-22 0.1-4.0 0.80-0.95 0.05-2.00 Native thermogenic gas, late biogenic gas Low coal rank Powder River E 6.68 3.34 90-970 0.3-0.4 12.2-30.0 2-5 10-1 500 0.70-0.97 0.40-1.00 Biogenic gas Surat K2—E 1.40 1.28 200-800 0.4-0.6 10-50 1-8 1-1 600 0.90-1.00 1.00-3.00 Biogenic gas Alberta K 12.00 11.67 200-1 300 0.3-0.8 10-25 2-14 10-500 0.90-1.00 0.20-1.50 Extraneous gas, thermogenic gas, biogenic gas Hailar K1 1.30 1.60 600-2 000 0.3-0.6 2-110 1-10 Less than 1 Low-normal pressure 0.07-0.15 Thermogenic gas, biogenic gas Erlian K1 4.00 2.60 Less than 1 000 0.3-0.5 50-200 1-4 Less than 1 0.90-1.10 0.10-0.25 Biogenic gas