Ok I understand now were you are coming from, but from a semantic point of view,  the sentence from the press release is not the best.

The real meaning of the sentence is that the tool can investigate for up to 12 meters of depth from the sea bed to the bedrock the material.  In that material there will be some overburden (sterile land) and pay dirt.

 

For me the 12 metres is not the key point, it is the size of the target identified by the geophysical work...