Subsidence Analysis for Underground Coal Mining Operations: The Use of Airborne Laser Scanning Data

This project applied airborne laser scanning technology for the detection of mine subsidence over a broad area, a commercial application not widely used in the Australian underground coal mining industry. The objective of the project was to prove the latest generation airborne laser technologies as a reliable and objective source of vital subsidence monitoring data for an underground coal mine and to demonstrate its potential as a complementary or alternate method to conventional geodetic subsidence detection and monitoring. Pre-mining airborne laser scanning (ALS) data together with ALS data acquired post-mining was processed together to measure the level of vertical subsidence that had occurred across the mining area. Rigorous quantitative comparison of ALS and geodetic survey data was carried out over a range in topography and vegetation densities allowing the technology to be assessed with a variety of environmental variables. Integrated spatial analysis and field checking of the elevation differences of the datasets showed well defined subsidence zones around the areas of longwall mining. The analysis also indicated that there was good correlation between ALS and geodetic data, although som