Integrating subsurface data from existing vertical wells can greatly assist targeting and placement of infill horizontal wellbores. CoViz 4D enables a high degree of data integration and collaboration across the asset and adds value to analysis and decision-making. Data courtesy Rocky Mountain Oilfield Testing Center and U.S. Department of Energy.
Lithologic distribution—shale, sandstone, silt, etc.—has a major impact on the recoverable reserves in unconventional reservoirs. Many of the most successful unconventional plays, such as Williston, Permian, and Anadarko Basins rely on thinner conventional reservoirs embedded in the major source rock shales for their most prolific portions of the play.
These basins are quite mature with an abundance of older vertical well data that can be analyzed to determine which portions of the basins are most suited for the best economic returns. Understanding where the best portions of the play are—through 3D visualization of subsurface data—is a primary concern to oil and gas technical professionals and corporate management.
Challenges in Utilizing Subsurface Data
Although there is an abundance of data available, the biggest challenge in utilizing these data to explore the lithology, identify bypassed pay, and determine its economic potential is data integration. Volumes of data acquired or generated during the extant life of the reservoir—seismic surveys, core samples, well logs, cellular grids, oil, water, gas production—have different formats. Individually, each data set characterizes an attribute of the reservoir as a snapshot in time.
However, when these data are combined and presented in a common environment for visualization and analysis they achieve their greatest value, allowing data to be interpreted in the context of other relevant subsurface data. This approach is particularly helpful in identifying unconventional opportunities in declining reservoirs.
To address the challenge of data integration, visualization, and analysis, reservoir teams worldwide are using CoViz 4D, a software unique in its ability to enhance the understanding of hydrocarbon assets. Three key CoViz 4D capabilities that give these teams unprecedented understanding of a reservoir using older subsurface data, as well as recently-acquired data, are: the data registry, 3D visualization of subsurface data, and an extensive set of analytical tools.
A Data Registry to Easily Share Discipline-Specific Information With Others
CoViz 4D provides a data registry that enables all members of the reservoir team to share discipline-specific data with other team members. Team members simply indicate the source of the data. CoViz 4D supports an extensive range of data, including seismic surveys, reservoir simulations, structure models, microseismic data, well events, and production data.
The data registry keeps track of where that data is located and makes it accessible to other team members. This capability enhances decision making regarding reservoir assessment in the following ways:
- Eliminates time wasted searching for relevant reservoir data
- Team members can easily access data even if they are not experts in the methods or tools used to acquire, generate, or manage the data
- Facilitates a better understanding of reservoir characteristics and potential by evaluating subsurface data in context
- Allows teams to see how development decisions have impacted reservoir performance via access to relevant data acquired throughout the lifetime of the reservoir
The ability to easily access relevant data acquired or generated through the life of the reservoir gives every member of the development team—geologists, geophysicists, well designers, drilling and completion engineers, production engineers, and even accountants—the information and the context they need to make the best-informed decisions regarding recovery methods throughout the economic life of the reservoir.
3D Visualization of Subsurface Data to Uncover Unconventional Opportunities
CoViz 4D enhances the value of discipline-specific data sets, not only by making it easy to access the data, but also by combining these data, regardless of source or format or time acquired, into a shared environment that enables reservoir teams to visualize the data to reveal geology, well trajectories, pay zones, and production data in great detail. With a common view of reservoir properties, teams can:
- Study the locations of existing wells and understand how lithology has influenced well placement
- Learn how geology and geophysical attributes have influenced reservoir development
- With the aid of recently-acquired data, identify areas of additional opportunity, such as unconventional plays to recover previously inaccessible pay
- Use time-step data (4D) to learn how the reservoir has responded to development and operational decisions over time
- Evaluate the results of previous unconventional well development to determine how geology, petrophysics, and completion methods have influenced well performance
Reservoir teams can use CoViz 4D to obtain a clearer understanding of the interplay among all the factors that influence reservoir performance when all relevant subsurface data is visualized and presented in a shared, collaborative environment.
Expansive Set of Tools for Reservoir Analysis
Analytics tools that allow reservoir teams to explore relationships among subsurface data are essential in understanding a reservoir’s properties and economic potential. Those tools can help characterize reservoir properties using formal models, determine which reservoir properties positively or negatively impact reservoir performance, and continually improve the understanding of an unconventional reservoir as additional data are acquired and analyzed.
CoViz 4D offers an expansive set of analytics tools, including:
- Integrated calculator to apply arithmetic operations on any quantitative reservoir object
- Synthetic seismic volume generation using reservoir simulations in analytical workflows for faster seismic history matching, from a flow ⁄saturation model to petroelastic (velocity and density) model
- Interactive tools to calculate property averages and attribute extractions in seismic and cellular space
- 4D geomechanics workflow to calculate overburden displacement, strain, stress, and seismic time-shifts resulting from reservoir thickness changes
Analytic tools allow geologists, geophysicists, and petroleum and production engineers to explore and quantify data relationships that may not be obvious when viewed as 3D or 4D reservoir models. Analytics provides an added dimension in understanding and quantifying the potential of previously unavailable pay.
Analytics provides an added dimension in understanding and quantifying the potential of previously unavailable pay.
Maximize the Value of Older Subsurface Data to Identify Unconventional Opportunity
As the number of producing fields decline, the importance of recovering previously-missed pay increases. Operators looking for additional recovery opportunities in declining reservoirs spend less time on analysis and reach better-informed conclusions when they can leverage the wealth of existing reservoir data and collaboratively visualize and analyze it. CoViz 4D facilitates this analysis with powerful 3D visualization of subsurface data sets from multiple sources to provide an enhanced understanding to determine which portions of a reservoir are most suited to the best economic returns.
