Applications of geophysical measuring methods for the exploration and securing of old mine workings near the surface using the example of the former lignite mine “Robertshall”

In the former lignite mine "Robertshall" near Hamburg damage to the surface was caused by the collapse of underground cavities originating from old mine workings of a lignite mine which had been in operation between 1920 and 1922. During the investigation of the subsurface by drilling it was noticed that the existing mine plans are incomplete....