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A new feature added to Winlog Version 4 is the ability to represent deviated boreholes.
Boreholes are designed to obtain information in the third dimension, ie. at depth, below the two-dimensions of the earth's surface. Today it is relatively easy to determine position on the surface, but not so at depth. Unfortunately, all too often, the path of the hole is erroneously assumed to follow the original dip (or inclination) and azimuth (or direction) established at the collar, at the top of the hole. Numerous borehole surveying devices have been developed, none of which are perfect, however quite accurate results are possible by using the right tool in the right hole.
A borehole deviation survey is usually accomplished by moving a probe along the hole and sensing the movement of the probe relative to one or more frames of reference which may include the earth's gravitational field, magnetic field or other inertial reference, and/or by sensing the distortion or bending of the housing of the probe itself. The different methods each have their own advantages and limitations such as ability / inability to operate inside steel casing, speed and complexity of operation, accuracy, cost, distance between measurements, ruggedness and reliability.
Winlog provides five different calculations from which to calculate borehole X,Y, and Z coordinates based on a deviation survey which includes the measured depth, inclination angle, and the azimuth angle. These include:
1) Average Angle method
2) Balanced Tangential method
3) Minimum Curvature method
4) Radius Of Curvature method
5) Tangential method
The user can select which method Winlog uses to correct borehole depths on the Deviation Survey tab of the Preferences form. To display the Preferences form, select the Preferences menu item from the File menu