Minage Valade

Underground location (vertical identification)

Vertical location by positionning transmitter (transmitter BPS) is the best way to locate accurately either an underground or a subaquatic cave up to 300 m deep.

Thanks to our expertise and the robustness of our transmitter, we can operate quickly and in extreme conditions.

Radius strength : 400m Deep max strength : 300m
Axial accuracy : < 0.7%
Vertical accuracy : < 0.1°
Depth accuracy : < 1.5%



What is the underground location?

The underground location is the determination of the true vertical point above ground of an underground place. The underground topography made by this way will perfectly match the surface area topography. When cavers can access the place to be located, the BPS transmitter is the more accurate process that can be used.



For more than 20 years, Daniel Valade has developed his own transmitter. Some can be used in extreme situations like subaquatic caves.

Thanks to our transmitter, we find the best position, above ground, to drill the underground location.




Surface area location
and determination of depth

How does it work?

The reciever (above ground) collects the magnetic field (signal) sent by the transmitter. A transmitter is positioned at the targeted place in a natural or artificial cave. The magnetic field is located on the top by the reciever. So an accurate point can be deternined above the ground.
This technology allows deep measurements that are more accurate than that obtained with an altimeter because the transmitter is not affected by atmospheric pressure changes.

Movie about one of the location we completed for the Conseil Général du Lot (District Counsil).


Possible uses

  • Finding the best drilling point (wiring, ventilation, mining, water supply, etc...)
  • Validate the accuracy of underground topography
  • Defining the best position for drilling above ground
  • Accurate deep measurements
  • Define relative locations of several caves or underground structures

Technical performances

  • Localization up to 250 meters deep : 800 meters diameter surface area reception
  • Autonomy : 4 hours
  • Accuracy of deep measurement : + / - 2 meters
  • Weight and dimension : 3 kg, can be hold in a 15 liters water tight can.
  • Accuracy of the location : less than 1 meter
  • More accurate and less expensive than topography.

A study to fit your needs

Daniel Valade company is sufficiently experienced to bring you valuable advice and help for your project.
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