| 摘要 |
<p>A method and system for tracking a borehole produced by a drill bit (50) having a probe attached thereto by means of an externally produced magnetic field. The magnetic field is produced by a current loop (1) made up of straight line segments which facilitates the calculation of the magnitude and direction of the magnetic field at any point in space. An ammeter (5) measures the current flowing the loop (1), the value of which can be used to calculate the theoretical magnetic field vector. In order to locate the probe, magnetometers (52) within the probe are used to measure the magnetic field. Accelerometers (51) within the probe allow the determination of the probe's orientation which enables the measured field vector to be compared to the calculated field vector and the probe's location thereby ascertained.</p> |
