Petrophysics
The Petrophysics bar allows you to execute petrophysical calculations such as shale volume, porosity, saturation, pore pressure, and more using well log data available in the project.
For more information about input formats and methods used in each calculator, refer to the dedicated chapters for each calculation module.
The Bar consists of 2 sections: Views, Execute.
Views section:
Open predefined petrophysics calculation workspace.
The workspace includes the following views by default:
Execute section:
This section includes calculators that operate on well log data. Each button opens a wizard or dialog for the selected operation.
Base properties – Opens the base property calculation wizard. This module allows estimation of hydrostatic pressure, temperature gradient, overburden stress, and effective stress using well depth and fluid parameters. Input parameters include fluid density, gravity constant, and depth range. The resulting curves can be saved as new well logs for further use in pore pressure or stress analysis.
Shale Volume – Opens the shale volume calculation module. Select the method (e.g., linear, Larionov) and input the gamma ray or other relevant logs.
Porosity – Opens the porosity calculation wizard. Supports various methods (density, sonic, neutron, or combined) and requires input of matrix and fluid properties.
Saturation – Opens the saturation wizard. Allows configuration of water saturation methods such as Archie or Simandoux, and includes parameter input for resistivity logs, cementation exponent, and formation water resistivity.
Mineral Volume Estimation – Opens the mineral volume estimation wizard, which estimates the volume fractions of the rock-forming minerals from the well-log responses.
Pore pressure – Opens the pore pressure estimation module. Includes methods like Eaton’s and Bowers’, allowing you to define input logs (e.g., velocity, resistivity) and calibration parameters.
Lithology interpretation – Opens the lithology interpretation tool. This module enables defining lithotypes (e.g., sand, shale, limestone) based on log value ranges and logical rules. Users can set multiple lithotypes, assign weights to log parameters, define matching thresholds, and manage conflicts between overlapping definitions. The result is a lithology log representing the dominant lithotype per depth interval.
Edit LAS curve – Opens the LAS curve editing dialog. Provides options to modify existing well log curves using filters (moving average, median, bandpass), apply depth shifts, or perform mathematical operations with expressions. Includes a history panel for tracking applied modifications and undoing changes.
For more information refer to this topic: LAS editing
LOG calculator Opens well log calculator. This tool is used to generate new well logs by applying mathematical expressions to existing logs. It enables the creation of customized well log data for further analysis.
For more information about the well log operations please refer to Well log calculator
ML Log prediction Opens Machine Learning based wizard that enable Log data prediction calculation
Workflow integration
The petrophysical wizards on this bar can be added to the project Workflow and re-run as tasks. This applies to Base properties, Shale Volume, Porosity, Saturation, Pore pressure, Lithology interpretation and Edit LAS curve. Each of these wizards has the same row of bottom buttons:
- Save to workflow – stores the wizard and all of its settings (selected wells, input and output curves, method, method parameters, user-defined constants and output names) as a Workflow task.
- Run – executes the calculation with the current settings (this button replaces the former Calculate button).
- Save – stores the result in the well.
- Close – closes the wizard.
Reopening a task from the Workflow panel restores the wizard with its saved settings, so they can be reviewed, edited, run, and saved back to the task.