Get Stress View
Get Stress_1 View
The results that are shown in this view will satisfy the input data that is defined. No other values satisfy both the observed wellbore breakouts or tensile failure / tensile region (TF-TR) and the known values of Sv, Shmin, and Pp within the selected bounds. Note that it is not necessary to know the rock strength or elastic moduli in this analysis. Because aDVANCED STRESS & failure computes the stress parameters based only on the position of the failure mode, it is possible to put limits on the allowable rock strength based on the measured breakout width.
The colors within the region of allowable magnitudes and azimuths of SHmax indicate the magnitude of UCS and To, which is consistent with the occurrence of breakouts or TF-TR of the width entered in the data input window respectively.
If the message ―NO MATCH ACHIEVED‖ appears, it means that there are no feasible magnitudes and azimuths of SHmax within the search region. You may try either choosing a smaller search domain, or increasing dBO, by entering the appropriate values in the setting view display option. By increasing dBO, you avoid the risk of choosing a search range for which breakouts cannot occur. A match can always be found if dBO is at least 10 degrees (by default, dBO is 15º). Once Get Stress_1 finds a locus of consistent stresses, you can decrease the search window to refine the result.
Get Stress_2 View
This view shows the results of the Get Stress_2 calculations with all magnitudes of SHmax and Shmin plotted that are consistent with the observed breakout or Tensile fracture / Tensile region position and other available information; color is a function of rock strength or Tensile strength (depending of user choice). The width of the region is a function of the uncertainty in the breakout or Tensile fracture orientation (dBO/ dTF).
The dashed line is Shmin = SHmax, the right-hand side of the Mohr-Coulomb failure polygon of Constrain Stress; valid stress states must lie to the left of this line, where SHmax > Shmin. Click the Stress Polygon button to display the range of allowable horizontal stress magnitudes superimposed on the complete Mohr-Coulomb failure polygon. The polygon outlines all possible stress magnitudes limited by the frictional strength of the crust for the given value of sliding friction. Get Stress_2 restricts the range of allowed stress states to those that match the position, as well as the width, of the observed breakouts. Uncheck the Stress Polygon in the Display options to return to the previous output window.