Formation Mechanism and Potential of High-Productivity Wells in F Oilfield
Abstract
The M reservoir in F Oilfield has entered a medium- to high-water-cut stage, characterized by complex water flooding conditions, high water invasion risks in scattered infill wells, and extended-reach wells predominantly located in structurally low areas, leading to complicated oil-water relationships. Concurrently, the fluvial channels in F Oilfield are narrow with frequent sand body variations. In areas not covered by seismic reservoir prediction — such as near fault boundaries, narrow channels, and layers not penetrated by horizontal wells—the interpretation accuracy of reservoirs in well-controlled low positions is poor, posing a risk of drilled thickness failing to meet standards. This necessitates precise deployment to achieve “high efficiency with fewer wells”. To address challenges in profitable production development, this study systematically analyzes the performance of recently drilled high-productivity wells in F Oilfield. The research identifies five main controlling factors governing the formation of high-productivity wells, reveals the mechanisms by which structure, reservoir properties, fault sealing, and remaining oil distribution control these wells, and establishes a comprehensive five-dimensional evaluation system integrating “structure-reservoir-fault-remaining oil-economics”. Based on this, geological sweet spot identification criteria for high-productivity well potential extraction are established, deployment principles and three types of favorable target sand bodies are determined, and an optimization process along with quantitative evaluation criteria for potential zones and well locations are developed. Ultimately, a set of technical strategies for tapping the potential of high-productivity wells suitable for F Oilfield is formulated. This study provides an important theoretical basis and technical support for refined potential extraction and profitable development of low-permeability oilfields during the high-water-cut period.