A New Approach for Evaluating Layer Productivity before Well Completion

This work presents a new methodology using formation testing at openhole conditions for layer fluid identification and reservoir parameters estimation. Real-time pressure and fluid identification data are obtained from the new wireline MDT* Modular Formation Dynamics Tester. The tool`s dual packer module makes zone isolation possible. Field cases from wells located in the San Jorge Gulf basin illustrate the testing methodology. The reservoir and well parameters of permeability (vertical and horizontal) and formation damage are obtained from pressure transient analysis of buildup and interference pressure data taken in several wells. The evaluation method is consistent with results obtained from testing after completion (cased hole DSTs). Evaluation results can be used to decide whether to complete or abandon the zone of interest. Fluid type is identified in real time using the OFA* Optical Fluid Analyzer module. Evaluation of anisotropy on a productive zone scale from the vertical interference test is shown.