The Impact of Regional vs. White Sand on Long Term Multi-Fractured Horizontal Wolfcamp Well Production

Abstract

Abstract Proppant selection is an important aspect of hydraulic fracture completion design. Recently, the industry has moved toward the use of lower cost regional sand as the propping agent for multi-fractured horizontal well completions in the Permian Basin Wolfcamp. An evaluation of early time production data indicates that there is minimal difference in first year well production with the use of regional vs white sand. These comparisons are the subject of SPE 199751, Shale Frac Designs Move to Just Good Enough Proppant Economics. However, does this conclusion hold up when evaluating longer term well production. The subject of this paper is a follow-up study which incorporates re-allocated production and new data to facilitate the evaluation of regional vs white sand on longer term well production. A database consisting of reservoir, completion, frac and production data from 297 Multi-Fractured Horizontal Wolfcamp B Completions was assembled. New production allocations and previously unavailable production data are incorporated to allow comparisons of two and three year cumulative oil, gas and water. A Self Organizing Mapping (SOM) methodology was used to determine relevant well groups of like reservoir characteristics in which valid comparisons of regional vs white sand well production can be made. This type of approach is intended to normalize on differences in well reservoir characteristics and compensate for inconsistencies in the data that could impact comparisons of regional vs white sand well production. Within this database there is a wide variation in reservoir characteristics and completion design. These wells were completed by many different operators using lateral lengths up to a high of almost 15,000 ft., proppant intensities from 500 to 4,000 lb./ft. and frac stage spacing from 59 to 769 ft. In the performance of this project, it became apparent that reservoir characteristics along with completion design factors have a dominate impact on multi-fractured horizontal Wolfcamp B well production. It was critical to factor out these non-sand type factors to quantify the influence of regional sand usage. As we would expect, wells with the most pay thickness, greatest permeability along with relatively higher pore pressure, effective porosity and low water saturation have the greatest potential for hydrocarbon production. The most productive completion types have longer length laterals, more frac stages (closer spacing), more proppant and fluid intensity.1 Based on this evaluation, the use of lower cost regional sand as the fracturing propping agent results in a negative 4% impact on first year well production. After 3 years of production this negative impact has increased to over 7% compared to white sand completions. In areas with better reservoir quality rock, the negative impact of regional sand use can be more significant. Conversely in areas with poor reservoir quality rock, the use of regional sand use has a less significant impact on well production.