Create Intersections

To calculate and display intersections:

Select the Calculate Intersections check box on the Intersections tab of the Drillhole Log form.

Specify an Interval file with one or more fields containing assay values. You can display values, graphs and a downhole reference scale, positioning these elements on the screen according to your requirements.

Use the Input Fields grid on the Intersections tab of the Drillhole Log form to select the names of the fields in the Intersection file that will be used to calculate the grade of intersections. The input fields you select must be numeric fields. The intersection calculation will calculate an average, weighted by the sample length (To field - From field) of these fields.

Calculating grade intersections is an interactive process which is done in the display:

  1. On the Drillhole | Drillhole Log tab, in the Edit group: Click Create Intersections. This puts the log display into Create Intersections mode.

  2. Use the mouse to click on a Start interval:

  3. When you move the mouse after clicking on the first point, a shaded selection box is displayed as you use the mouse to move the cursor bar up or down the log.

    4. The cursor bars automatically snap to sample boundaries. It is not possible to have an intersection representing a partial sample interval. The second cursor bar can be located above the first cursor bar without affecting the validity of the calculation.

  4. A second mouse click creates the intersection and the weighted average of the intersection fields (grade fields), the thickness of the intersection, and the From and To intervals are displayed in the Properties window:

    5. Intersection calculation fields are setup on the Intersections tab of the Drillhole Log form.

    On the Drillhole | Drillhole Log tab, in the Edit group: Click Save Intersection to write the Intersection results to the Output file. Alternatively, select Save from the right-click menu.

    If you defined a Code field, you will be prompted for a Code value.

Displaying Intersections