With therapid sust ainabledevelopmentofChina ', seconomy the
demandforcoalisincreasing therebyleadingtoanincreaseofthe
extent,, Anddepthofmining.ThedepthofcoalmininginChinahas
, increasedatanaverageof10mperyear andcertainminesare extendingtheirdepthatarateof. 20 - 50mperyear.Increasingin
, miningdepthleadstoariseingroundstress gaspressureandgas content [,], 3 4 andthenumberandintensityofoutbursteventshas
.IncreasedinChinaeachyear.Severalshallowandnon-outburstcoal
seams. Aregraduallybecomingoutburst-pronecoalseams.Inparti -
cular manycoalminesinthecentralandeasterndevelopedareasof,,
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