Page 190 - Well Logging and Formation Evaluation
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AXDIR (deg) 120 AXDIR
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Depth
Figure 12.1.4 Field Due to a Monopole: AX dir
In order to find the closest approach of the two wells, do as follows.
Consider that the survey well has an inclination a. If the vector pointing
toward the pole (r) is an angle q from the HS direction in the sensor plane,
the angle between r and the horizontal is given by:
[ (
f = arcsin 1 - cos q ( )]*sin ( a). (12.1.24)
The TVD (true vertical depth) of the pole is given by:
( )
TVD pole = TVD sensor - *sin f (12.1.25)
x
where the TVD of the sensor is at the point of closest approach to the
pole.
The direction to the pole in the horizontal plane, j a, relative to the
survey azimuth, is given by:
