Use of a New Well Productivity Model and Post-Frac Rate-Transient DataAnalysis to Evlauate Production Potential of Refracturing Horizontal Wells inShale Oil Reservoirs

摘要

Production data and analytical models derived from coupling the linear flow in the reservoir and the linearflow in hydraulic fractures were used in this study to optimize fracture spacing for maximizing productivityof shale oil and gas wells through refracturing.This study concludes that productivity of multi-fracturedhorizontal wells is inversely proportional to the fracture spacing.The shortest possible fracture spacingshould be used to maximize well productivity through refracturing.This supports the practice of massivevolume fracturing where as many as perforation clusters with the shortest possible spacing are used forpumping massive proppant into the created hydraulic fractures.Production data analysis indicates that themulti-fractured horizontal oil and gas wells could have higher productivity if they were fractured with lessperforation cluster spacing.Mathematical model analysis implies that reducing the cluster spacing from 70ft to 15 ft through refracturing can doubled well productivity,with the Minimum Required Cluster Spacing(MRCS)determined by well completion constraints(packers,perforation clusters,and casing couplings).Result can be checked for fracture trend interference on the basis of analyses of pressure transient data orproduction data.