Overview: Well Testing (February 2005)

Abstract

The industry spends millions of dollars to achieve success in reaching the target objectives for an exploration well. Even with impressive petrophysical data, the well-test information will determine the potential commerciality of the exploration project. Similarly, in the production environment, reservoir descriptions that are always more complex than idealized reservoir models present unique challenges to the accurate char still can arrive at valid yet surprisingly different conclusions from the same well-test analysis. Even with current advances in technology, there is no replacing the sound engineering judgment necessary for analysis of a complete set of well-test data. Our industry continues to seek improved and innovative methods of improving our well-test data-gathering and -analysis methods. Accuracy of the pressure/volume/temperature data is fundamental to the well-test analysis, and errors in this input will compromise the final analysis. Numerical methods that more accurately describe reservoir conditions during testing will allow modeling of more-complex descriptions. Tools to allow earlier and more accurate analysis of reservoir fluids and rock properties accelerate our understanding of a new prospect and can save time and cost of unnecessary delays in analysis and completion recommendations. Real-time production monitoring of wells can lower the cost of gathering ongoing well-test data and improve our understanding of the reservoir relative to infrequent snapshots of data common to most projects. Advances are being made in all the components of well-test-analysis technology. Fluid-sampling and -analysis tools; well-test-analysis software; and pressure-, temperature-, and rate-monitoring technology are improving. Reservoir models are adapting to more-complex environments. Artificial intelligence is used in efforts to discern accurate well-test-analysis results with less applied-engineering judgment. However, with increased technology, a flood of additional data and models are available from which a rigorous engineering analysis must be completed. Engineering judgment with assistance of the technical capabilities of an entire multidisciplinary team is still the most critical component needed to determine the unique solution that will most accurately complete a reservoir and well description. The following pages provide examples of the broad range of reservoir information being gathered, analyzed, and managed to make the exploitation of hydrocarbon resources more efficient and profitable. Additional Well Testing Technical Papers Available at the SPE eLibrary: www.spe.org SPE 90236 - Uncertainties in Standard Analyses of Boundary Effects in Buildup Data SPE 90960 - Simultaneous Estimation of In-Situ Multiphase Petrophysical Properties of Rock Formations From Wireline-Formation-Tester and Induction-Logging Measurements SPE 92041 - Grid-System Requirements in Numerical Modeling of Pressure-Transient Tests in Horizontal Wells