Well Landing Zone Decisions in Unconventional Plays: A Rock Mechanistic Approach

Revisiting the fundamentals of hydraulic fracturing theory has assisted in rebuilding a log-based methodology that estimates the likelihood of vertical fracture growth. The suggested method can be used as a quick screening tool to support landing zone decisions in unconventional plays. The workflow combines the essential elements of fracture mechanics for rock mechanical applications to provide a more realistic vision of how a hydraulically induced fracture may grow in the vertical dimension. It incorporates the use of a density log, a log-derived stress profile along with the elastic properties, and the injection pressure to estimate the probability of fracture growth vertically through horizontal bedding planes. The workflow can identify a preferred landing zone for horizontal wells, or alternatively, preferred perforation intervals in the case of vertical wells. The paper illustrates two case studies in shale formations that assess the advantages and limitations of the suggested approach.