The Overburden Calculation view

The Overburden Calculation view is an in-built template of the Well View which is used for composing the overburden density and overburden stress logs. By default on opening, the view has a lithology track, a caliper composite track (if the solution has caliper data) and the compositor-overburden density track. Perform different operations on the view using the Well View toolbar.

The Compositor-Overburden Density track contains the composite bulk density and the pseudo-density log (if selected), calculated from the composite acoustic log. You can add user-defined exponential and polynomial curves to the track using the context menu option Log Trends > Add.

Composing the overburden density and stress curves using trend line

You can fit the trend line graphically by dragging either the entire trend line or the two end points to the proper position. You can also move the trend line more precisely using the Inspector.

  1. Click on the density log in the compositor-overburden density track for which you want to fit a trend line. Once selected, the log becomes active. Right click on the log and select Log Trends > Add and select the parameters of trend line equation. A trend line is added for the selected log.
  2. Click the trend line in the track so that it becomes the active object. Once the trend line is the active object, look in the Inspector, where you will find the a and b parameters for the trend line. These can be manually adjusted to properly fit the trend line to the data. Trend parameters can also be adjusted via Template Editor.
  3. You can now compose a overburden density curve, which you then use to calculate the overburden stress curve. The Overburden Calculation view uses the same functionality for composing logs as used in the Log Composition form.
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  4. Activate Create Composite Log tool in the Editing Tools panel.
  5. Click in the track at the desired depth and drag up or down to create the selection window. Double-click the log of interest to use it in the composition.
  6. You can select any of the calculated overburden curves, including the user-defined curves, for any segment of the composite. Continue selecting areas and curves until you have created a continuous overburden density curve for the entire well.

You can use the overburden stress curve in the pore pressure and fracture gradient calculations.