Underground » Geology
This final report is timely in tat it is being published at a time when 3D seismic is being routinely used by a number of exploration groups in the Bowen.
The very readable report provides the reader with an understanding of the recent advances made in this exciting field and highlights the benefits to be gained from 3D seismic.
Successful longwall coal mining requires certainty of geological conditions and knowledge of any geological structures which might disrupt the coal seams. Seismic reflection surveying provides one of the best methods of providing infill information between boreholes and providing targets for detailed exploration. In recent years, 3D seismic reflection surveys have been undertaken at a number of minesites and superior seismic results were obtained.
In this project the ability of seismic reflection methods to resolve localised geological features has been examined from a theoretical viewpoint and through using data obtained in recent 2D and 3D seismic surveys undertaken in the Sydney and Bowen Basins. A major finding is that faults with throws as small as 1 to 2 m are detectable using high quality 3D seismic survey data together with computer aided interpretation. Dykes on the other hand, remain difficult to detect and are unlikely targets for seismic reflection surveying even at 8 m thickness.
The results of 3D seismic surveys at four mines plus a number of additional 2D surveys are presented and discussed in this report. The results show how subtle details in the coal seams are revealed. Techniques for computer aided interpretation are also demonstrated.
The benefit of detailed coal seam mapping by seismic reflection surveying has thus been demonstrated. The on-going employment of seismic surveying appears assured.