3D model with a digitized paper contour map (with horizontal well lines) draped on the reservoir surface with colored contours blended. Good correlation exists between the two sets of contours. Vertical wells are shown in yellow and directional wells are in green. A smaller detailed property model can be seen near the center showing gamma ray distribution. Data used by permission of owner.
Reservoir development teams improve their chances of finding new opportunities in existing fields when older, traditional subsurface data can be combined with newer, recently-acquired subsurface data. Data acquired or generated throughout the life of a reservoir provide valuable information regarding geologic and petrophysical properties, well locations, completion methods, and production metrics. When these data are combined, they present a comprehensive view of the reservoir. However, because historical data is highly variable in terms of sources and formats, combining the data to create an integrated, comprehensive reservoir model often presents the greatest challenge in maximizing the value of these data.
Addressing the Challenge of Subsurface Data Integration
Worldwide, operators faced with this challenge have implemented CoViz 4D which has the unique ability to combine an incredibly wide range of subsurface data to create a detailed, 3D reservoir model. The types of data include: geological, petrophysical, simulations, well events, microseismic, fluid production data, and many additional subsurface data types, even traditionally found in a paper format.
In fields that have been produced for decades, there can be significant volumes of well logs, geologic cross-sections, and contour maps that exist in paper format. Thanks to modern technology, these data can be captured digitally and incorporated into the reservoir model. To make the process as easy as possible, CoViz 4D offers an editing function to help transform a paper contour map into a 2D digital grid for easy integration into a reservoir model.
The ability to easily integrate a wide range of subsurface data sets—for example, geomechanical and traditional subsurface data—and combine them into a comprehensive 3D reservoir model, enables reservoir teams to collaboratively analyze all relevant subsurface data in context. This approach gives reservoir teams an in-depth understanding of the factors that have guided previous development decisions and lets teams quickly review how past decisions have affected reservoir performance.
Integrating Geomechanical and Traditional Subsurface Data
As asset teams acquire data throughout the course of a reservoir’s productive life, CoViz 4D makes it easy to incorporate these data into a 3D reservoir model. Recently-acquired geomechanical data and traditional subsurface data combined can show how a reservoir has changed over time in response to production. This information enables teams to more accurately and confidently plan further reservoir development.
With the data available from recent coring, core testing, geophysical logs, and transient pressure analysis geotechnical, engineers can then use these data to update their geomechanical models. Young’s modulus of elasticity and Poisson’s ratio help calculate specific metrics regarding in-situ rock stress. Formation porosity, permeability, leak-off coefficient, and bottom hole pressure guide the determination of the optimum completion and stimulation method(s) for the new horizontal wells.
Efficiency in Geomechanical Calculations
To aid in geomechanical analysis, CoViz 4D offers a geomechanics module that uses well-known relationships and formulas (Geertsma subsidence equation). This method is an alternative to the time-consuming finite element analysis of complex reservoir changes. It allows geophysicists to quickly obtain an understanding of reservoir deformation, deriving volume change, uniaxial thickness change, stress, velocity change, and seismic time-shifts. The results of the analysis can then be incorporated into an existing 3D reservoir model to provide engineers with a current and comprehensive visualization of the reservoir.
Image file of a formation log from an old vertical well displayed along the well trajectory. 3D model and nearby horizontal wells in the background. Data used by permission of owner.
CoViz 4D Maximizes the Value of Geomechanical and Traditional Subsurface Data
The combination of geomechanical and traditional subsurface data (and the creation of a comprehensive 3D visualization of current reservoir conditions) enables reservoir engineers to revisit a field with the goal of identifying new opportunities. With this detailed level of understanding, they are better prepared to:
- Identify target regions previously overlooked because of incomplete data;
- Assess geologic or geomechanical risks that could jeopardize well drilling or long-term unconventional well performance;
- Develop economically feasible trajectories to reach bypassed pay; and
- Determine the most effective completion and stimulation methods.
CoViz 4D excels in its ability to integrate, visualize, and analyze the widest range of subsurface data generated or acquired throughout the life of a reservoir. CoViz 4D maximizes the value of geomechanical and traditional subsurface data through shared access and collaborative evaluation of reservoir conditions. With a comprehensive visualization of a reservoir, development teams are far better prepared to maximize a reservoir’s economic potential using improved drilling technology and unconventional recovery methods.
CoViz 4D maximizes the value of geomechanical and traditional subsurface data through shared access and collaborative evaluation of reservoir conditions.