Power-law correlations of mine subsidence for a metal mine in China

Abstract

Great damage has been done to the earth’s surface as a result of mining. An important concern is whether power-law occurrence rate–scale statistics that are used to study many natural hazards, such as landslides and volcanic eruptions, can be used to study mine subsidence. The ground subsidence in Longshou Mine, China, is analysed using data from a 12·5-year-long (May 2003–November 2015) continuous field investigation with 488 global positioning system monitoring points. The results of occurrence rate–scale statistical analysis fit well with a power-law relationship – that is, M (S) ∼ S −β . The subsidence power-law parameter varies between 1·06 and 2·18 for settlement between 2 and 257 mm. Additionally, the uplift parameter varies between 1·01 and 2·45 for uplift between 1 and 123 mm, regardless of changes in the goaf geometry and rock mass integrity. The power-law model of the results of the occurrence rate–scale statistical analysis is established, and the underlying controls of the power laws, the self-organised criticality of the subsidence system and the application of power laws are discussed. The spatial self-similarity and long-range spatial correlations of mine subsidence are expressed by significant power-law dependencies, which suggests that both large- and small-scale mine subsidence may follow the same physical and mechanical principles.