A New Method to Monitor the Coal Mining Subsidence by Gravimetry

Coal mining subsidence seriously affects the mine natural and ecological environment. Leveling is the traditional method to monitor the coal mining subsidence. It is possible to monitor the subsidence by gravimetry instead of leveling based on the negative linear correlation between the gravity change and the height change. Equations are derived to monitor the subsidence by gravimetry in the paper. Height change errors are analyzed by considering the uncertainties of gravity data and coal masses based on the error propagation theory. The probability integration method is utilized to simulate data of gravity, height and coal mass as well as the corresponding random errors. These data are processed with the new method to monitor the subsidence and its precision. The experimental results show that gravimetry can replace leveling to monitor the coal mining subsidence when the precision of gravity data is up to level of 3 μGal.