1D Geomechanical Earth Model
Purpose
The 1D Geomechanical Eath Model allows users to evaluate the minimum and maximum horizontal stresses and evaluate the mudweight window to better understand intervals where shear failure or borehole breakout may occur. The calculations consider the wellbore inclination and azimuth relative to the stress field orientation.
Primary Outputs
The following curves are the primary interpretations made in this module:
| Curve Name | Description |
|---|---|
| max_hz_stress | Maximum horizontal stress in psi |
| min_hz_stress | Minimum horizontal stress in psi |
| max_hz_stress_ppg | Maximum horizontal stress in ppg |
| min_hz_stress_ppg | Minimum horizontal stress in ppg |
| pmw_low | Lower mudweight window in ppg |
| pmw_high | Upper mudweight window in ppg |
Discussion
This module is used to investigate wellbore stability and to help identify potential problem intervals. In order to effectively use this module the user should have already utilized the Geomechanics, Synthetic Shear (if a measured shear sonic is not available), and Pore Pressure modules.
In conducting the interpretation it is important to pay attention to the lithology as many of the correlations are specific to certain rock types. For methods that utilize a conversion to a static Youngs modulus it is also important to select methods applicable for the stress regime.
Minimum horizontal stress can be calculated via four methods and maximum horizontal stress by three methods.
In order to take full advantage of the visualizations it is importan to import your mudweight data as this will allow a visual inspection of where the pore-pressure exceeds the mudweight (blowout hazard) and where mudweight exceeds the horizontal stress, which can cause compressive or tensile failures.
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Purpose The Quick Start module is designed to help users quickly set dozens of common parameters by selecting a handful of basic options from dropdown menus. Parameters There are three parameters that are set on a zone-by-zone basis and two parameters that are set on a full-well basis. These are as follows. Discussion The parameters are linked to what are called named_defaults in the software. These are collections of defaults that can be set through assigning a single parameter.
Sample data to get started
Need some sample data to get started? The files below are from data made public by the Wyoming Oil and Gas Commission. These will allow you to get started with petrophysics, mapping, and decline curve analysis. Well header data Formation tops data Deviation survey data Well log data (las files) Production data (csv) or (excel) Wyoming counties shapefile and projection Wyoming townships shapefile and projection Haven’t found the help guide that you are looking for?
NMR Interpretation Module
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