# Creating a gram meter plot (grade*true thickness) long section (2D)

When I was in Uni as an MSc. student, a long section gram meter plot of the mineralization very common for geological study. The gram meter value equals the true thickness of the ore body in meters (see fig below) multiplied by the grade in ppm from the same sample point in the lode. The long section requires the 3D Oblique projection into a 2D long section, at that time I manually calculate the true thickness in Excel and used Global mapper combined with Surfer to apply the projection.

After I work as a resource geologist for years, I use to work with 3D models, the last time I did a 3D project into a 2D was more than 10 years ago.

Recently, I was asked to map out a gram-meter long section plot for a gold vein lode, and this time I would like to do something new.

In this study, more than 3000 drill holes with multiple directions were used, which makes the manual calculation time-consuming. I must find a better way to get the true thickness.

This time the calculations were performed using leapfrog geo software and validated with python math for key drill holes.  On the plot, the semitransparent contours display the ore grade * thickness as a gram meter plot for the lode. the length of the borehole intercept ore lode was also displayed as points with text information which included Drill hole ID, intercept length and composites of au_ppm.

Step 1 composite the drill hole assay data in the vein solid by surpac. Then input it into leapfrog as a drill hole data table, which allows you to create a vein domain model.

Step 2 once the domain has been created, I can use the domain output to evaluate the thickness variable. For evaluating thickness, I have to export the domain thickness to a CSV file and re-import it as vertices points.

Step 3 with the vertices points I can calculate the gram meters from au_ppm*true thickness and then create a new interpolation of the gram meters constrained by the domain, by evaluating the interpolants onto the domain.

Step 4 create a new long section in leapfrog or export gram meters vertices points as CSV, then input it to surpac for rotation into 2D.

can I do all steps in leapfrog only, without jumping to other software?

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