Section 8: Feature Evidence Tools

  • Feature evidence analysis works best on plan-view geophysical datasets. Blend outputs are currently not valid as input for analysis.
  • Feature evidence layers are created by drag-dropping datasets onto the Evidence Layer List (Figure 1: Panel 5). Three types of evidence are generated: ridges, valleys, and edges.
  • Feature evidence layers are required to be linked to an interp group item to display with On-Lines or spotlight modes.
  • Feature evidence layers may also be blended
  • Feature evidence layers also have the option for pyramid texture tiles similar to grid and image datasets.

An example for creating and visualising feature evidence:

  1. Select a geophysical dataset previously used for creating interpretation features.
  2. Drag the geophysical dataset onto the Evidence Layers list box. The process to generate an evidence layer may take a few minutes.
  3. Once generated, evidence layers can be linked to interp items by dragging the layer onto the ‘+’ node under the contents (features attributes) of the interp item.
  4. By default, the Evidence type is set to Ridges with the visualisation mode is set to Switch this mode to On-Lines once linked to an interp item (Figure 8a). The outline around each line can be switched off by turning off the Show Lines option in the Show group options in selected group’s context menu.
  5. Adjust the width of the line visualisation by the { and } The strength of the luminance contribution from the geophysical dataset can also be adjusted by the and + keys.
  6. While in On-Lines mode, select and edit existing interpretation features.
  7. Change the Evidence type to Valleys. Since strong valley responses can occur in low intensity regions, the intensity of the luminance can be inverted by the 9 and 0 Note the evidence mix can be toggled on/off with the ~ or | key.
  8. Change the Display mode to Spotlight (Figure 8b), and move the cursor around the geophysical dataset. The radius of the spotlight area can be adjusted by the { and } keys, and the luminance contribution can be adjusted by the and +
  9. While in Spotlight mode, create additional interpretation features by left clicking.
  10. Change the Evidence type to Edges, and the Display mode to Full (Figure 8c). The Colour option is now accessible, and the colour map used for displaying the feature evidence map can be changed.
  11. Note the quantitative measures for the feature evidence in the lower left corner of the main display area. These measures are updated in real-time to the feature within range of the mouse cursor.
Figure 8: Three modes of visualisation for the data evidence layer: (a) On-Lines mode, (b) spotlight mode and (c) Full mode.

Figure 8: Three modes of visualisation for the data evidence layer: (a) On-Lines mode, (b) spotlight mode and (c) Full mode.