Graphing Interval Data

Petra can plot any numerical interval “real value” versus depth or another real value.  This can be particularly useful for quickly seeing how a quantity such as mud weight changes with depth, or understanding the relationship between two different kinds of data like porosity and permeability.

To view an interval graph, first select the correct well in the Main Module.  On the Interval tab, select the right interval table.  In the example below, the “CORE” table is selected.  Finally, select the “Edit details” button in the upper right on the Interval tab.  

On the Graph tab, select “Depth vs Z” or “X vs Z” on the first dropdown menu.  “Depth vs Z” shows the selected values for the interval fields selected on the Z1, Z2, and Z3 dropdown menus on the vertical axis relative to depth on the horizontal axis.  The example below shows how porosity varies with depth.

“X vs Y” shows a scatter plot for the two interval fields selected on the X and Y dropdown menus.  The X value is plotted on the horizontal axis, and the Y value is plotted on the vertical axis. The example below shows how permeability varies with porosity