Abstract: Influenced by the complexity inside the faulted -vuggy carbonate bodies, the first target drill-in rate of the fractured-vuggy reservoir in the Tarim Basin is low, complex formation pressure and stress systems lead to difficult drilling operation and frequent incidents, and it is hard to optimize effective measures for well completion and increasing production capacity. These have delayed the oil and gas development process. Based on geomechanical research, the idea of geological-engineering integration is proposed which involves interdisciplinary cooperation, fine fault interpretation and faulted-vuggy body characterization, and drilling success rate can be increased by quantitative optimization from well location, drilling process to measures related to well completing and production capacity increasing in the West Yueman oilfield in the northern Tarim Basin. In the study, by focusing on the distribution of faulted-vugg bodies and principle stress azimuth, the orientation of natural fracture permeability and well stability, optimization methods have been established for well location and deviated trajectory, the distribution of formation pressure has been predicted using well-seismic data, and based on which the wellbore structure was optimized. In addition, four kinds of methods for well completion and increasing production capacity have been proposed based on near-wellbore stress distribution, wellbore orientation and reservoir distribution. Application of these methods in three wells including W22, W20, etc. provided high production, and made continuous exploration breakthrough in the West Yueman block, northern Tarim Basin. The study idea proposed in this paper provides references for exploration and development of other fractured-vuggy carbonate reservoirs.

Key words: geology-engineering integration, fractured-vuggy carbonate, geomechanics, well trajectory optimization, measures for increasing production capacity, classification