Multiple-Source Data Provide Insight Into Hydraulic Fracture Geometries

Abstract

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 195524, “Insight Into Hydraulic Fracture Geometries Using Fracture Modeling Honoring Field-Data Measurements and Post-Fracture Production,” by Neil Stegent, SPE, Ron Dusterhoft, SPE, and Hari Menon, SPE, Halliburton, prepared for the 2019 SPE Europec featured at the 81st EAGE Conference and Exhibition, London, 3-6 June. The paper has not been peer reviewed. Using planar fracture models to match treatment pressure and improve understanding of fracture-geometry generation is not a new concept. At some point during the progression from vertical to horizontal wellbores, however, many within the industry forgot about the learnings that still can be gained from current fracture models. The complete paper demonstrates the benefits of honoring data measurements from a multitude of potential sources to help engineers do a better job of including more diagnostics into routine operations to provide additional insight and result in improved models and completion designs. Introduction Many sources of reservoir, drilling, and completion data and measurements are available to well operators. However, in nearly all cases, a balance must be achieved of what can be captured at a reasonable cost and the associated value of the information gained. It is unrealistic to acquire high-density data sets for every well in an entire field because of the prohibitive costs, but understanding what is available and knowing what questions need to be answered can enable a more-cost-efficient means of acquiring the correct information to address specific challenges. Diagnostic Data and Measurements The complete paper contains a summary of some relevant tools and technologies and a short description of the information that can be captured, the importance of this information, and how it can be used; examples are discussed wherein some of these tools are combined to provide useful completion-design information. Gathering Production Information Production-logging tools are useful for characterizing and better understanding reservoir performance and optimizing production. The production logs are typically run after the completion of a well, either in a cased or open hole. The logs are used to determine the allocation of wellbore inflow to different zones and to identify areas of production problems such as crossflows and leaks. In low- and ultralow-permeability reservoirs with horizontal drilling and increases in the number of fracturing stages, understanding the production rate of each fracturing stage is important. Therefore, a post-fracturing evaluation might be necessary for optimization of multistage fracture design. Artificial-lift installations on post-fracture completions can be an obstacle to acquiring good production-log data in unconventional wellbores. Tracer Technologies Multiple tracer technologies are available for fracture diagnostics, and, while all such methods provide useful information, the results can be misleading when the methods are used independently. Conditions within the reservoir are changed significantly during the completion process and again during production. While wells can be in communication during hydraulic fracturing operations, that does not mean that the same wells will be in communication during production, because not all of the created fractures will remain open and conductive when production and reservoir depletion has begun.