This lead-zinc mine is located in Inner Mongolia Autonomous Region, and after many years of mining, there are numerous goafs underground. To determine the distribution and morphology of the goafs within 400 meters depth, two methods were carried out: SRT and 3D underground robot laser scanning.

In the above figure, the red solid line corresponds to the three-dimensional robot laser scanning results of the mined-out area, while the white dotted line shows the suspected location of the mined-out area by SRT.

It can be observed that the two results are consistent, confirming that SRT is highly accurate in locating mined-out areas.