Analysis of refracturing activities in the major shale plays in the United States

Refracturing of existing horizontal multistage wells has increased over the past decade in the oil industry. This work aims to investigate all the refracturing operations in the most active shale plays in the united states (Bakken, Niobrara, Marcellus, Permian, Eagle Ford, Barnett, and Haynesville) in terms of completion technique, candidate selection, treatment types, and refracturing production efficiency. To collect the data of the refractured wells, an advanced data analytics approach was applied to separate the refractured wells from 170,000 wells reported in FracFocus, a public chemical registry for hydraulic fracturing in the United States, and combine it with DrillingInfo database, a database of oil and gas production in the United States. More than 1200 refractured wells (2008-2020) were identified for study across the major shale plays in the United States. Trends in completions and production of these refractured wells were identified, for example, the most common type of treatment fluid used in refractured wells was hybrid fluids. In addition, an extensive literature review was conducted to identify criteria for refract candidate selection. Using perforated length as a proxy for stage data, 39 wells of the 1200 refractured wells production were found to be sufficiently similar to be grouped for production comparisons. This analysis, coupled with individual well plots of full production histories, demonstrate that while refracturing can restore production rates significantly, the production of the refractured well commonly declines rapidly --Abstract, page iv