Study Of Fracture Stimulation Technology In Deep Layer Of Complex Lothological Gas Reservoir

Daqing deep volcanic gas reservoir have to be big-frac treatment to produce commercially composition only for it's deeply buried(3500-4650m), high temperature(130-180℃) and dense structure. Because of Lava layer mature cavern fissure, multiple fractures is ruptured and extended when at reform treatment. There are three obvious characters: multiple pumps stopping, much friction resistance, high leaking-off which add to the fracturing difficulties, so far as to operation failures. Backward in fracturing technique comes to be a bottleneck of prospecting and exploitation deep gas reservoir.The paper are in view of the condition existing natural fracture and post fracturing forming multi-fissured on Daqing outer-ring deep zone volcanic rock,established fall off curve analysis mathematical model,utilize G function to decide formation nature fracture's parameter of developing extent,open pressure,closed pressure etc. ,pre-determination accuracy fluid efficiency and fracture propagation condition;based on the differentiate between deep volcanic rock and normal sandstone break mechanism establishing two types of"multi-layer steamed bread"and"cactus"which can relatively description the physics and mathematical model of volcanic rock fracturing extend process of"multi-fracture";on the bases of elastic mechanic developing terrestrial stress profile analysis software,which can utilize sonic logging datum calculating the profile of terrestrial stress and rock mechanic, and first achieved the combination type from geologic layering to terrestrial stress layering,heighten the scientific and pertinence on fracturing design. Based on above research,synthesize considering the respect on stress profile,fissure open and extend mechanism,leak off diagnose achievement etc. to optimize fracturing design,optimize treatment raw materials,in view on well site multi-fracturing,high friction resistance,low differential stress between reservoir and barrier bed,high leak off problem etc.,definition correspond effectively control measure,thereby forming a set relatively mature stimulation technique for Daqing exploration area deep volcanic rock gas reservoir .Because of utilizing of technology supporting measures , the unfavorable factors of early screen-out of stimulation has been settled satisfactory,Success rate of fracturing has improved from 36.0% in 2002 to 91.3% right now。...