Production optimization in shale formations: Focus on proppant delivery schedules and mitigation of fracture conductivity damage

Abstract

This study presents recent advances in modeling capacity and provides optimization guidelines for key operational parameters controlling well performance, using real well data. A new Gaussian solution method can both accurately forecast well rates prior to drilling and history match actual well performance after completion once early production data become available. Unlike other history-matching tools, excellent matches are achieved with daily production data spanning just a few months. The study also addresses key challenges in achieving precision in hydraulic fracturing and horizontal well design, emphasizing unresolved subsurface heterogeneity, variability in treatment quality, and modeling tool limitations. Advanced analytical methods, such as the Gaussian Production Forecasting (GPT) method, offer improved accuracy and computational efficiency for production predictions. Empirical data from the Eagle Ford and Wolfcamp formations demonstrate significant performance gains over the past decade, driven by optimized fracture spacing, increased lateral lengths, and enhanced proppant usage. However, performance gaps persist due to poor proppant conductivity, closure stress impacts, and proppant transport inefficiencies. This study highlights the critical impact of fracture conductivity damage on shale well performance, as revealed by Gaussian well performance curves derived from historical data. The findings emphasize the need for integrating advanced modeling tools, optimizing proppant delivery strategies, and improving transport simulations to achieve sustained productivity gains in shale reservoirs.

Keywords

Production optimization / Hydraulic fracturing / Fracture conductivity / Wolfcamp shale / Eagle ford formation / Gaussian solution method

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