A GIS-based approach for the mapping of potential mining impacts on cliff-lines
The ability to assess the potential mine subsidence impact undoubtedly can be valuable for subsidence management plans and any decision-making process carried out prior to mining. The paper describes a quantitative spatial methodology for the mapping of potential mine subsidence impacts on cliff-lines using a Geographical Information System (GIS). The approach is developed using a GIS-based weight-of-evidence methodology with the following characteristics:
• A data driven technique for impact assessment during the preliminary stages of mine design when the field data is limited.
• Identification of pertinent controlling factors in rockfall occurrence phenomena.
• The analysis of the level of influence for each controlling factor, weighting and combining evidential factors using the weight-of-evidence method.
• The mapping of the probability of a rockfall occurrence within the area of interest.
A mining area in Australia was used as a case study; two models were developed based on different mine layouts for a proposed longwall mining area. In the first layout, longwall panels were planned to extend beneath the steep sided areas of the nearby river, and a second layout in which the mine layout was modified so that mining does not occur directly beneath or within 50 m of the steep slopes. The results from the case study show a significant reduction in probabilities of rockfall occurrence when mining is avoided within 50 m of the nearby river cliffs.