WellCAD Basics - Advanced Logic Technology

146 - BOOK 1 - WELLCAD BASICS
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Right click on a factor column header to open a context menu providing the
following options:
Add New Factor – will add a new column to the list.
Remove Factor – deletes the column from the list.
Rename Factor – allows setting the column title.
To enter a correction factor simply set the top and bottom of the depth interval over
which you would like to apply the correction first (e.g. top and bottom of the cased
section). You can type in a number or use the key words top and bottom to determine
the top and bottom of the log automatically. Click in the cell of the factor column.
The Formula dialog box will open (see 1.5.1 Formula Parser for details on how to
use the control in the dialog box). In the Formula line enter the factor read from a
chart or compose a formula using a reference to e.g. a caliper log to compute a
dynamic correction factor. The equation to be entered could be determined using
the WellCAD cross-plot module. Plot correction factors against hole size and use
the regression tool to find a relationship.
All correction factors – constant or computed – will be multiplied with the raw value
read from the selected log at the end to determine and output a corrected value.
As dead-time and correction factors are often tool specific you can store all
parameters in a configuration file (*.ini) by clicking on the Save button. To reload a
configuration click the Load button and select the desired *.ini file.
When opening the Borehole Corrections Dialog box the last parameters used are
reloaded.
1.5.12 Computing Well Deviation Data
The Common > Process > Borehole Deviation menu contains three different
tools to compute:
- Borehole Azimuth, RBR (High-Side), and Tilt from magnetometer and
accelerometer (inclinometer) readings.
- Easting, Northing and TVD using borehole azimuth and tilt as input
channels.
- Closure Distance, Closure Angle and Dog Leg Severity (DLS) from
borehole azimuth, tilt, Northing and Easting.