Selection of candidate wells for re-fracturing in tight gas sand reservoirs using fuzzy inference

ARTUN Emre,KULGA Burak

Table 3 Data used in the study cases and calculated results of the indices.

Parameter/index Granite Wash Williams Fork Fracture length 170.1 m (558 ft) 277.5 m (910.3 ft) Fracture permeability 9.903 μm2 8.793μm2 Fracture width 4.83 mm (0.19 in) 5.69 mm (0.224 in) Hydraulic-fracture quality index 16 41 Reservoir thickness 20.4 m (67 ft) 59.9 m (196.5 ft) Porosity 9.1% 10% Permeability 0.001 27×10-3 μm2 0.019×10-3 μm2 Reservoir characteristic index 22.6 48.9 Temperature 93.3 °C(200 °F) 60 °C(140 °F) Drainage area 0.67 km2 (165.3 acre) 1.51 km2 (371.9 acre) Initial pressure 41.4 Mpa (6000 psi) 27.6 Mpa (4000 psi) Initial Condition Index 50 50 Bottom-hole flowing pressure 8.4 MPa (1215 psi) 6.9 MPa (1000 psi) Number of hydraulic fractures 30 10 Length of the horizontal section 1219.2 m (4000 ft) 609.6 m (2000 ft) Operational Index 59.2 43.2 Initial production rate 36.5×104 m3/d (12.912 MMSCF/d) 415.2×104 m3/d (146.7 MMSCF/d) 3-year cumulative recovery 0.85×108 m3 (3 BCF) 3.85×108 m3 (13.6 BCF) 5-year cumulative recovery 1.02×108 m3 (3.6 BCF) 4.56×108 m3 (16.1 BCF) Performance index 15.3 27.7