Do We Get the Right Position?

Literature for applied geophysics present rules of good practice for field work and descriptions on the different methods. Parameters like depth, frequency, resolution and further conditions are discussed in detail. The fundamental requirement that geophysical data have to be linked to a position seems to be self evident in times of GNSS and laser total stations.

Whereas surveying is an engineering discipline, the today positioning equipment implies that everyone can produce exact positioning data. Many geophysical experts perform their positioning with quite rudimentary surveying knowledge and blind faith into GPS & Co.

In civil engineering applications we observe rectangular shaped inspection areas as well as long linear structures like railway tracks or roads. Surveying a soccer field sized site requires different positioning technologies than surveying along highways. Standard positioning methods do not longer apply to this problems.

Focussing on GPR in civil engineering a survey speed of 80 km/h is required today. With velocities of more than 22 m/sec latency of surveying systems gets quite relevant.

Different available technologies of surveying are discussed in this presentation. Manufacturers as well as users are addressed to work on a unified methodology that could be implemented as a standard in future.