Practical Methods for Analyzing Well Test and Production Data from Devonian Shale Reservoirs

摘要

The report presents the derivation and application of two analytical models and a companion automatic history-matching algorithm. The first model was designed to analyze production data in a manner somewhat similar to decline curves but with considerably more sophistication. The second model was designed for well test analysis. The goal of both models is to describe a given reservoir by estimating certain parameters, including permeability, skin factor, and drainage area. Both models are enhanced by a sophisticated, statistically sound parameter-estimation scheme. The theoretical development of the models focuses on analytical solutions to forms of the diffusivity equation. Care was taken so that the resulting solutions can be applied to a variety of reservoir types. The models can be used for gas and (single-phase) oil production, single- and dual-porosity reservoirs, finite and infinite-acting reservoirs, and include the effects of skin factor and gas desorption. The well test model also includes wellbore storage effects. Although analytical models of this type have been described elsewhere, their versions are the most comprehensive analytical models to date.