# Distribution of kriging error and stationarity of the variogram in a coal property

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## Abstract

If a particular distribution for kriging error may be assumed, confidence intervals can be estimated and contract risk can be assessed. Contract risk is defined as the probability that a block grade will exceed some specified limit. In coal mining, this specified limit will be set in a coal sales agreement. A key assumption necessary to implement the geostatistical model is that of local stationarity in the variogram. In a typical project, data limitations prevent a detailed examination of the stationarity assumption. In this paper, the distribution of kriging error and scale of variogram stationarity are examined for a coal property in northern West Virginia.

## Key words

distribution of kriging error variogram stationarity coal geostatistics contract risk## Preview

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© Plenum Publishing Corporation 1986