Borehole surveying

In modern petroleum and - natural gas drilling several holes will be, especially in the offshore area of a drilling rig drilled . In order to avoid collisions of the individual holes, it is necessary to determine the exact course of the individual holes. Because of the deflection of the earth's magnetic field by protective piping already in the ground, it is not possible to carry out these measurements using a magnetic compass . Gyrocompasses or, more recently, inertial navigation systems are used for this purpose , which are usually lowered into the borehole using a measuring cable. Gyroscopic compasses transmit the direction and inclination of the borehole to the surface, where the trajectory of the borehole is then calculated. Inertial navigation systems directly calculate the path they have covered by double integration of the acceleration values and the direction by integrating the rotation rates measured by gyroscopes .

Web links

• Borehole Deviation and Borehole Surveying (accessed October 8, 2015)
• Geophysical borehole measurements in engineering practice (accessed October 8, 2015)