Mathematical Geology

, Volume 18, Issue 7, pp 635–652 | Cite as

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

  • Bruce A. Bancroft
  • Gerald R. Hobbs


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 


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Copyright information

© Plenum Publishing Corporation 1986

Authors and Affiliations

  • Bruce A. Bancroft
    • 1
  • Gerald R. Hobbs
    • 2
  1. 1.Consolidation Coal CompanyPittsburgh
  2. 2.Department of Statistics and Computer ScienceWest Virginia UniversityMorgantown

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