Content of PetroWiki is intended for personal use only and to supplement, not replace, engineering judgment. SPE disclaims any and all liability for your use of such content. More information
-Differences in rock — segments showing different responses when measured.
-This is represented by covariance models that have major and minor ranges of different distances (correlation scale or lengths). There are two types of anisotropy: geometric anisotropic covariance models have the same sill but different ranges, whereas zonal anisotropic covariance models have the same correlation ranges, but different sills.