This query is slightly ambiguous as can refer to a few different technical fields.
The use of satellite radar or LiDAR to monitor ground subsidence , landslide risks, or structural stability in construction and mining. 3D Ground Monitoring
Specifically the 3D Ground Monitoring app used with Conrad brand imaging devices for treasure hunting and locating metallic objects or structures underground. This query is slightly ambiguous as can refer
Could you clarify which of these you are looking for a guide on? 3D Ground Monitoring