Log analysis and uncertainty evaluation for petrophysical characterization
Mistral is an advanced easy-to-use multi-mineral log analysis software for multi-well log interpretation and evaluation of petrophysical uncertainties.
The approach to formation evaluation is a multi-log inversion, based on a constrained Gauss-Newton optimization method. It is particularly valuable because it provides confidence intervals for the interpretation results, coupling the Monte Carlo method to the optimization routine. The multi-solution combination option and zone sub-division make the software powerful to analyze mixed lithologies. The software output provides the volume of the system components (fluids and solids), porosity and water saturation profiles, and the associated uncertainties based on user-defined errors potentially affecting both log measurements and model parameters.
Non-linear regression analysis based on the Gauss-Newton optimization method;
Error analysis using a Monte Carlo simulation that gives the confidence interval for each volume;
Uncertainties on logs, conductivity model parameters and fluid densities are all taken into account.
User-defined vertical zonation of the formation
User-selected probability distribution for uncertain parameters
Multi-solution combination allowed
Easy to use
Friendly interface for parameter zoning and editing
Common saturation equations available
Comprehensive visualization tools (cross plots, areal plots, volume and log plots)
Easy data loading
User-guide providing helpful tutorials
Short training needed for expert log-analysts, no retraining for occasional users