【摘要】 受天然裂缝和倾角的影响,水力裂缝在斜井井壁处可能存在3种起裂方式,分别为沿天然裂缝面张性起裂、沿天然裂缝面剪切破裂和从岩石本体起裂。根据地层地应力状态及天然裂缝的产状,建立了裂缝性地层斜井水力裂缝3种起裂方式的起裂压力计算模型,提出了水力裂缝起裂方式和起裂压力的判别方法。现场实例表明:该模型能成功地解释天然裂缝性地层的破裂压力。更多还原

【Abstract】 There are three possible initiation modes for hydraulic fracturing on the wellbore influenced by trend and dip of natural factures,including tensional fracture along natural fractures,shear fracture along natural fractures and tensional fracture initiating from rock body.On the basis of the occurrence and geometric distribution of natural fractures and the stress status of naturally fractured formations in directional wells,some models for calculation of hydraulic fracturing initiation pressure were established.The identification method for determining hydraulic fracturing initiation mode and initiation pressure was obtained.A field case verified that these models could be successfully used to predict the fracture pressure of naturally fractured formations.更多还原