Production Forecasting using Type Wells, Diagnostic Plots and Hybrid Models

Journal Title
Journal ISSN
Volume Title

With recent advancements in the field of unconventional shale gas production, there lies a need to estimate the gas reserves in the best possible manner. Production forecasting for unconventional wells is one of the areas which is still being explored in the industry.

In order to get the estimated ultimate recovery (EUR) of unconventional wells, industry uses the method of type wells to calculate well rate. A flaw in the method was identified during the calculation of well rates, which may result in incorrect EUR values. A new method was proposed to solve this problem, so that a standard can be maintained to forecast the production using type wells.

During the analysis of diagnostic plots to identify flow regimes, one of the issues faced is the presence of outliers. The current methods used tend to overlook this problem which not only adds extra noise to the data, but can also cause incorrect interpretation if not removed. A method of removing outliers and filtering data using decline curves is suggested.

One of the issues, while creating a reservoir model to forecast production, involves the type of completion design. Application of a homogeneous model in wells where heterogeneous completion is encountered, might lead to an incorrect evaluation. A hybrid reservoir model was developed to forecast cases with transient and boundary dominated flow.

Production forecasting, Reservoir Engineering, Unconventional reservoirs, Shale gas, Reserves estimation, Decline curve analysis