COALSEAM THICKNESS PREDICTION WITH GEOSTATISTICS

Coalseam thickness is necessary data for coalmine design and mining.The correct predication result of coalseam thickness not only can provide good geology guarantee for coalmine,but also can bring great economic benefits.Coalseam predicting can be calculated using fitting or regression analysis method according to the known borehole coalseam thickness,but because of the limitation of borehole data amount,there are large errors existenting in predicting thickness between the wells or wells outside area.Seismic data have a good continuity in the transverse,if sparse borehole data could be combined with dense seismic data,it is helpful to increasing the thickness predicting precision between the wells or wells extrapolating zone.Cokriging method is a dualistic,unbiased and optimal interpolation method in geostatistics,and based on regional variables theory and variogram basic tool.Borehole coalseam thickness and seismic amplitude in the space distribution have some regulation and local randomicity,so they can be described as regional variables,and can be simulated by variogram,the thickness estimation can reflect thickness variety regulation of well data,also can direct variety trend of seismic data.According to actual measurement thickness data on the roadway coalseam exposing points in the research area,some Cokriging predicting thickness examination have been done,and the predicting thickness error has become lower.The predicting precision has largely increased.The thickness predicting method is especially suitable for some coal mines which have done 3D seismic exploration.