4D seismic difference shown at a single time step along with a reservoir simulation grid. Comparison of the seismic response from the fluid injection can be done on multiple timesteps. Data used with permission of owner.
The oil and gas industry has been utilizing seismic attributes for improving reservoir simulation models and predicting behavior for a long time. However, despite the immense use of data and technological advancement, the challenges with developing a correlation between the reservoir simulation and seismic attributes remain intact. This is mostly due to the dynamic nature of reservoirs. The varying conditions within a reservoir can be difficult to quantify and predict throughout the life of the field.
Importing 4D seismic data into a comprehensive viewing environment can enhance the interpretation and accuracy of reservoir simulations. The data allows interpreters use of temporal and spatial attributes to analyze the changes in a reservoir over time. The ability to visualize these changes further elevates analysis. Software with effective interpretation and visualization abilities illustrates the interrelationships between multiple parameters for enhanced attributes analysis.
Enhancing Accuracy with 4D Seismic Data
4D seismic data provides the potential for accurately interpreting geological, lithological, and petrophysical variations in a reservoir through the analysis of multiple attributes. These attributes may not be independent of each other and their analysis can directly affect modelled reservoir dynamics. The complexity and variation of attributes within a reservoir make it difficult to characterize and predict fluid changes.
The integration of seismic attributes into a reservoir simulation can be ideal in analyzing uncertainty. The analysis is utilized for effective field development. Establishing a correlation of reservoir simulation and seismic attributes allows the interpreters to accurately detail changes in reservoir fluids. It is possible to capture information including:
- Saturation and pressure changes
- Tracking changes in fluid contacts
- Location of changes in hydrocarbon distribution
- Changes in transmissibility of faults and fractures
The ability to integrate and visualize seismic attributes with a reservoir simulation can help verify the data and significantly increases the reliability of the simulation while reducing the risks in decision-making regarding asset development.
Enhanced Analysis of Reservoir Simulation Attributes
Qualitative and quantitative analysis and visualization tools enable on-the-fly integration of reservoir simulation and seismic attributes to identify changes in the reservoir. Software such as CoViz 4D easily imports the seismic data as a 3D grid, representing an array of amplitude values. Each cell in the reservoir simulation grid has multiple attributes assigned to it. Adding seismic amplitude to the grid can help to successfully establish the interrelationship and analyze variation in the attributes.
Software modules such as Sim2Seis for CoViz 4D utilize the ability to calculate seismic from, in part, reservoir simulation attributes. The seismic attributes can be cross-plotted with various reservoir simulation variables. The ability to run through multiple conditional simulations can help in a fast and easy analysis of the uncertainty and variations in the simulation process. It is possible to identify whether or not the flow predicted in the reservoir can be seen with the seismic analysis. The analysis of seismic volume can verify whether or not there is enough of a change.
CoViz 4D: Analyzing Seismic Attributes for Enhancing Reservoir Simulation
CoViz 4D provides an ideal platform for reservoir engineers, geologists, and geophysicists to visualize attributes at their correct geospatial location to analyze a reservoir’s current performance and predict future behavior. The Sim2Seis module for CoViz 4D facilitates synthetic seismic volume creation. The time-step analysis and interpretation of seismic attributes with other production data help identify patterns and variations over time. The comparison of 4D synthetic volume with observed 4D seismic attributes helps in developing a reservoir model that better matches the observation. Asset teams can rely on the predictions of the reservoir model for predicting reservoir performance, saving time and costs incurred during the process.