Straight
(constant for current well). For short or long intervals with stable shale
properties. The shale line is a straight line or trend-like curve that usually defines the highest right readings for the GR, SP, or Delta Phi curve with which it is associated. Over long depths you may need to modify this line to more closely track the associated curve’s relative position instead of the highest right reading for the entire curve.
You can use the following three types of shale line:
Straight
(constant for current well). For short or long intervals with stable shale
properties.
Automatic
Float. For improving the accuracy of Vsh for intervals calculations
where basic shale properties such as natural gamma radiation smoothly
changes by depth. This line is named automatic float because to save interpretation
time, AccuX automatically estimates the most likely position of the shale
line. A good example of implementation is the Belly River formation in
Western Canada.
User-Drawn
Float. For situations where AccuX cannot properly maintain an automatic
shale line or for multiple bore holes when changing the gamma radiation
from open hole to double casing then to single casing makes the trend
look step-like and not smooth.
To set straight shale lines for
single lines
1. Double-click the log, not a curve or top.
The Single Well Properties: Shale
dialog box appears.
2. Type the desired value in the shale value box, select the associated protected checkbox, and then click OK.
Note:
Ensure float
sand, float shale, and auto
shale checkboxes are cleared.
To set automatic float shale
lines
1. Double-click the log, not a curve or top.
The Single Well Properties: Shale
dialog box appears.
2. Select the float sand, float shale, and auto shale checkboxes and the associated protected checkbox for each as well as the protected checkbox beside the shale value box and then click OK.
To add user-drawn shale lines1. Double-click the log, not a curve or top.
The Single Well Properties: Shale
dialog box appears.
2. Select the float shale checkbox and the associated protected checkbox and then click OK.
Note:
Ensure the float
sand and auto shale checkboxes
and the associated protected checkbox
for each as well as the protected
checkbox beside the shale value box are cleared.
3. Ensure the curve
is selected and click edit curve
(
) in the Standard toolbar.
Note:
To cancel redrawing a curve, click
to clear edit curve mode.
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4. Click to define a series of points along the curve then double-click to define the last point in the series. |
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5. Click a blank area of the well log to clear the curve.
