Provide basin simulation output for multidisciplinary pore pressure prediction solution
Schlumberger proposed using Petrel Exploration Geology integrated with PetroMod petroleum systems modeling software to conduct the following:
- develop the model framework and paleohistory
- set lithological constraints, including porosity, permeability, and elastic properties
- simulate the evolution of pressure and stress through geological time
- analyze the different pressure generating mechanisms through geological time.
The PetroMod software simulator is a core part of PetroMod software workflows facilitating the incorporation of geological phenomena that affect pressure and stress through geological time.
Pressure generating mechanisms in the earth are relatively well understood, however, the relative influence of the various mechanisms
is poorly understood in geologically complex environments. An initial 2D modeling study was conducted using the SEAM Phase I earth model to test the influence of several pressure generating processes. Aside from disequilibrium compaction, pressures resulting from clay diagenesis, quartz cementation, basal heat flow variations, hydrocarbon generation, the influence of the salt on the subsurface rock stresses and the presence of faults were examined.
A 3D model was then built to incorporate these mechanisms and analyze their influence on spatial distribution of present day pressures and stress. The 3D basin simulation output which included pore pressure, stress, porosity, and ratio of smectite to illite was then used in a specifically designed theoretical rock physics model to develop a 3D anisotropic elastic model that could be used for seismic simulation.
Facilitated new predrill pore pressure prediction approach to mitigate catastrophic risks to the well and reservoir
Seismic simulation was conducted on the model to develop a set of synthetic seismic datasets for testing and improving methodologies for predrill pore pressure prediction.
The contribution of basin simulation output using PetroMod software, combined with the rock physics model, was critical to the success of the pore pressure prediction solution. Models that do not consider basin evolution ignore the crucial effects of specific rock properties on the modeled pressures. This new multidisciplinary approach, which ties basin simulation outputs to a geophysical simulation, combined the best of both disciplines to create a new methodology for pore pressure prediction that also improves seismic imaging.
Both the dataset and the workflow created during the project have been distributed to the SEAM Corporation industry partners for use as a benchmark to improve pore pressure prediction in the GOM and salt basins spanning the globe. This is helping industry mitigate potentially catastrophic risks to their operations during the predrill stage.