The horizontal Bakken/Three Forks play of the Williston basin has a long standing history of recompletion dating back to the late 1980s. While rapid evolution of horizontal completion design has allowed expansive Bakken/Three Forks unconventional acreage positions to reach economically viable levels, existing legacy completions have historically been difficult to invigorate to modern productivity expectations. Although recompletion is nothing new to the oil and gas industry, the techniques applied are highly variable and historically may carry disappointing and unpredictable results. As a need for better understanding of principle well development continues to evolve, so do better techniques in legacy well recompletion tactics to enhance both developed and undeveloped assets. Within the Bakken/Three Forks play, legacy development drilling and completion tactics are vast with significant productivity variances. Industry mindshare often incorrectly groups all recompletion methods into a single category. Differences in technical application, and associated value added per input cost, require subcategorization of recompletions to improve well productivity. A holistic identification process is required to appropriately match the service intensity associated with refracturing, reentry, or remediation to project costs and asset potential. The focus of this study is to compare and evaluate the production results attained from recompletions in the discrete subcategories of well refracturing, reentry, and remediation. Empirical datasets will be presented to define the project inputs and production value capture associated with each recompletion type. By integrating these workflows, enhanced recompletion design and execution can create value at previously unattainable commodity price levels. A comprehensive completion and production database of horizontal Bakken/Three Forks wells dating from 1987 to present has been developed to facilitate recompletion selection, design, and predictive production forecasting. Proprietary software that automates production analytics, combined with manual canvassing of over 10,000 wells, has provided an innovative method to cross-examine the Bakken/Three Forks play. By combining a multivariate assessment with probabilistic results, novel recompletion propositions can be successfully matched to project needs.

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The Powder River Basin in Wyoming has been exploited for the production of oil and gas for several decades. The development of horizontal drilling combined with large volume multi-stage hydraulic fracturing has initiated a new era of oil and gas production. More than 900 horizontal wells have been drilled in the Upper Cretaceous reservoirs of the Powder River Basin. Oil and gas producers often target more than one formation within any given acreage position. The focus of development has been in the Frontier Formation, the Turner sandy member, the Shannon and Sussex sandstone members of the Cody Shale, and the Parkman sandstone member of the Mesaverde Formation, along with the Niobrara Formation as an oil resource play. This paper presents a historical review of the completion designs and production trends from horizontal wells completed in the Upper Cretaceous formations. With a focus on multistage completions, well performance indicators are used in conjunction with a spatial sampling algorithm to identify dominant production influences attributed to completion and stimulation design. Using public records, a database was created, cataloging a completion metrics, including lateral pay length, fracture stage spacing, mass and type of fracture proppant, volume and type of fracturing fluid, and current production records. Correlations between fracture treatment design and hydrocarbon production are provided for each formation. Production type curves, initial production rates, and effective decline rates are presented for each formation. Geospatial trends in hydrocarbon properties, such as gas-oil ratio (GOR) and oil gravity are provided. The catalog of data and correlations provides a useful reference for exploring or developing acreage within the basin. Optimizing completion programs can be fast-tracked through the analysis of preceding completions and early time production indicators.