Abstract
The Horn River Basin is a shale gas play located along the northern border between British Columbia and the North West Territories, in the Western Canadian Sedimentary Basin. This unconventional reservoir utilizes horizontal wells with multistage fracture completions in order to produce fluids from the very low permeability shale. As with many other emerging shale plays, the Horn River play presents significant challenges to operators who are tasked with understanding, developing and producing the play as optimally as possible. Rate Transient Analysis (RTA) utilizes continuous production and flowing pressure data to characterize the reservoir and completion, for the purposes of reserves assessments, supporting field development and completion strategy and for supporting decisions around capital allocation. It has proved to be a very helpful tool for accelerating the "learning curve" of well performance in new plays, for which well - established best practices do not exist.
The purpose of this work is to illustrate how RTA can be applied in the Horn River, using a reliable, repeatable and technically sound workflow. To accomplish this, daily production data from eight multi-stage horizontal wells in the Horn River was analyzed using standard RTA techniques, including type curves, flowing material balance, specialized plots and analytical models. In addition to the standard approach, a probabilistic approach to RTA using Monte Carlo simulation is also included in this work, to address the significant non-uniqueness that exists in modeling unconventional reservoirs. The findings of this paper will include long term production forecasts, as well as our best estimation of reservoir and completion characteristics.