The Depth Index feature in In-Profile is used when the cable datum point has changed, typically either by the casing hight being changed or when using an Inclinometer Pro on a borehole that was previously read using a standard inclinometer.
The Depth Index
Correction copies a selected survey and shifts the depths by a specified
amount, then interpolates the data to fill in at those depths.
The following shows a borehole with the initial survey set from a standard Inclinometer and the second two survey sets from a Inclinometer Pro.
When plotted the two survey sets from the Inclinometer Pro follow each other closely but deviate from the Standard Inclinometer initial survey.
To Correct the Depth Index on the survey data from the standard inclinometer select the borehole data and in the Tools Tab select Depth Index Correction.
Ensure the correct Survey is shown and select shift up or shift down, because the Standard Inclinometers first cable marker is 250mm closer to the probe than that on the Inclinometer Pro it will sit 250mm further up in the borehole.
This means the data needs to be shifted down by 250mm
After clicking OK the software creates a corrected survey data set with a data and time stamp one second later than the original survey data set.
The plot below shows the corrected data added which now follows the profiles of the Inclinometer Pro.
The original survey data is still used as the initial reading set.
Set the corrected survey data as the initial run as shown below.
The original uncorrected survey can be deleted as required.
This process would need to be applied to all the surveys created prior to the casing height change or change of Inclinometer system.