Utica Well Performance Evaluation; A Multi-Well Pad Case History

Abstract

Understanding Utica formation hydraulic fracture and completion effectiveness is problematic given the wide variation in geology, hydrocarbon maturity and reservoir characteristics. Quite often, a positive production response from a well may be incorrectly credited to the completion and frac design when in reality the production was dominated by favorable reservoir characteristics. Conversely a poor production response from a well may be attributed to the completion and frac design when in fact poor reservoir quality is the controlling factor. The subject of this paper are detailed analysis of three direct offset wells which were performed by experienced engineers with reservoir knowledge for the purpose evaluating completion and frac effectiveness. When adequate production became available from these wells a detailed engineering evaluation was performed on each to estimate reservoir and frac characteristics. These evaluations consisted of (1) perform frac pressure matching for all treatments with a 3-D frac model, (2) perform production history matching on all phases with a numeric reservoir simulator and (3) estimating conditions within the fracture over time as the wells are produced. The methods used to perform these evaluations are not new, however they currently are underutalized by the industry today. The evaluations performed indicate that completion, frac design, operational and production issues can all significantly influence Utica well production and economics. In addition the findings show that in this case the hydraulic fractures are not very efficient.1–9 This inefficiency results in a relatively short effective fracture length which causes loss of productivity, recovery and return on investment.