Origin, hydrocarbon accumulation and oil-gas enrichment of fault-karst carbonate reservoirs: A case study of Ordovician carbonate reservoirs in South Tahe area of Halahatang oilfield, Tarim Basin

DING Zhiwen,WANG Rujun,CHEN Fangfang,YANG Jianping,ZHU Zhongqian,YANG Zhimin,SUN Xiaohui,XIAN Bo,LI Erpeng,SHI Tao,ZUO Chao,LI Yang

Table 1 Statistics on development effects of different segments of Yueman 2 fault belt in the South-Tahe area.

Segement ID Fault nature Stress intensity Fault length/km Fault width/km Geologic reserves/104 t Number of wells Initial productivity/(t·d-1) Average cumulative output per unit pressure drop/(t·MPa-1) Formation energy 2-1 Translation 4.1 0.12-0.56 50 2 25 250 Weak 2-2 Extrusion Weak 4.6 0.15-0.63 45 1 36 610 Insufficient 2-3 Tension Strong 3.9 0.74-1.95 284 3 68 2 232 Sufficient 2-4 Tension Strong 3.8 0.61-1.85 165 2 62 1 805 Sufficient 2-5 Extrusion Strong 2.3 0.59-1.68 116 2 43 812 Fairly sufficient 2-6 Extrusion Weak 2.5 0.14-0.69 88 2 32 600 Insufficient 2-7 Translation 1.9 0.15-0.41 26 1 20 226 Weak 2-8 Tension Weak 2.8 0.23-0.72 209 3 55 1 351 Fairly sufficient 2-9 Extrusion Strong 3.1 0.55-1.71 120 2 45 850 Fairly sufficient