How can you optimize reservoir performance with a well test program?

1 Well test objectives

Before you start a well test program, you need to define the specific goals and outcomes that you want to achieve from the well tests. Depending on the reservoir stage, these objectives may vary from estimating the initial reservoir pressure and fluid composition, to determining the reservoir boundaries and heterogeneity, to evaluating the well deliverability and productivity. You should also consider the technical, economic, and operational constraints that may affect your well test program, such as the availability of equipment, budget, and time.

2 Well test types

Well tests can provide a variety of information about the reservoir and the well. Pressure transient tests, for instance, involve altering the flow rate or pressure at the wellbore and observing the pressure response in the reservoir. This can help to estimate permeability, porosity, skin factor, and boundaries. Production logging tests involve running a tool or a string of sensors inside the wellbore to measure flow profile, temperature, pressure, and fluid composition along the well. Interference tests involve changing the flow rate or pressure at one well and examining the pressure response at another well. Lastly, drill stem tests involve isolating a section of the formation with a packer and flowing the fluid to the surface through a drill pipe. These tests can help evaluate reservoir pressure, fluid properties, and productivity index of a specific zone or layer.

3 Well test design

The well test design is the process of selecting the appropriate well test type, duration, frequency, and parameters for each well and reservoir objective. The well test design should be based on a sound understanding of the reservoir geology, fluid behavior, and well performance, as well as a realistic estimation of the uncertainty and risk involved. You can use analytical or numerical models, empirical correlations, or historical data to support your well test design decisions. You should also consider the health, safety, and environmental aspects of the well test operations, such as the disposal of produced fluids, the prevention of blowouts, and the mitigation of emissions.

4 Well test execution

The well test execution is the process of conducting the well test operations according to the well test design and program. The well test execution requires a close coordination and communication between the field personnel, the well test service providers, and the well test analysts. You should follow the standard operating procedures and best practices for each well test type, such as the pre-test preparation, the data acquisition, the quality control, and the emergency response. You should also monitor and document the well test performance and any deviations or issues that may arise during the well test operations.

5 Well test analysis

The well test analysis is the process of interpreting the well test data and deriving the reservoir and well parameters that are relevant to your well test objectives. The well test analysis involves applying various methods and techniques, such as the pressure derivative, the type curve matching, the history matching, and the material balance, to fit the well test data to a suitable reservoir model. You should also evaluate the uncertainty and sensitivity of the well test results, and compare them with other sources of reservoir information, such as the geological and petrophysical data, the fluid analysis, and the production history.

6 Well test optimization

The well test optimization is the process of using the well test results and insights to improve your reservoir performance and production strategy. The well test optimization involves applying various tools and methods, such as the nodal analysis, the decline curve analysis, the reservoir simulation, and the economic analysis, to optimize the well completion, stimulation, artificial lift, and injection for each well and reservoir scenario. You should also update and calibrate your reservoir model and forecast with the well test data, and identify any gaps or opportunities for further well testing and analysis.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?