Borehole Navigation

North-Seeking Gyro Sonde – Accurate Borehole Navigation.

Track the borehole! We are offering a brand new Geovista North Seeking Gyro. With real time recording and display. You can now profile your well in any environment. The Gyro can be run in any situation including magnetic such as in casing or drill pipe. This north seeking gyro can accurately survey all borehole profiles from vertical to horizontal  at high latitudes or inclinations with no reduction in accuracy. No surface equipment is required or calibration. This is a cost effective option in a market with limited suppliers of this expensive service..

The continuous inertial gyro log is aligned to a surface reference. Measurement drift occurs during the log due to the Earth’s rotation. This drift has to be described and corrected for. It’s a complex operation with a lot of user input. Typical errors are 10 degrees of azimuth every three hours of operation, if the tool is run properly.

The new North-Seeking (solid state fibre-optic) gyro sonde makes an independent stationary measurement at every five or ten metres of borehole. It locates true north and describes the tilt and azimuth of its location within two minutes. There is no need to return to the surface reference, align the sonde, measure total drift, analyse in-hole drift checks, describe closure, edit the in-hole checks to reduce closure etc.

  • The sonde is not affected by magnetic interference – it can be run in steel drill rods or casing.
  • All azimuths are in reference to geographical north.
  • There is no drift. Each survey is independent.
  • There is no field calibration required before each survey.
  • There is minimal human input or analysis required.
  • No surface reference alignment (by eye) is required.
  • Speed between stations 30 metres/minute.
  • The client can decide on station frequency 5m,10m, 20m..
  • The solid state system is accurate, rugged and reliable.
  • Precision can be checked by relogging a station.
  • Accuracy can be checked at a surveyed base test jig