Integrated evaluation and optimization of acid fracturing effectiveness in carbonate reservoirs: Experimental insights and field validation

作者：Peng Lu, Shuyu Li, Jinsong Liu, Nan Yuan, Heng Liu · 发表于：PLoS ONE · 年份：2025 · DOI：10.1371/journal.pone.0327027 · 被引用次数：5 · 研究领域：Hydraulic Fracturing and Reservoir Analysis、Drilling and Well Engineering、Reservoir Engineering and Simulation Methods

The development of carbonate reservoirs is confronted with significant challenges, including pronounced heterogeneity and suboptimal porosity-permeability characteristics. These challenges are particularly acute in low-porosity, low-permeability complex media, where acid fracturing often exhibits limited effectiveness. To address these issues, this study systematically evaluates post-acid fracturing effectiveness in carbonate reservoirs, aiming to provide robust scientific and technical guidance for stimulation optimization. A comprehensive multi-method assessment framework was employed, integrating laboratory experiments, operational curve analysis, real-time fracture monitoring, and production logging. Laboratory investigations quantified the reaction kinetics of diverse acid systems and the conductivity of acid-etched fractures. Results revealed that channel-like acid-etched fractures achieved a conductivity range of 120-150 μm²·cm, which is 3-5 times higher than that of smooth-walled core samples (25-40 μm²·cm). Field validation using Well A1 demonstrated strong correlations (R² = 0.85) between operational pressure fluctuations and natural fracture density. Viscosity-contrast fluid systems were shown to enhance conductivity by 40%-60% through selective etching mechanisms. The study's key innovation lies in identifying conductivity-governing factors through an integrated experimental-modeling approach, establishing criteria for optimal etching pattern development. The fram...