GSTAT: Zonal Anisotropy
On 12/06/2010 06:39 PM, Veronesi, Fabio wrote:
Suppose I have a dataset with a zonal anisotropy, by which there are two variogram models for two different directions. For assessing this anisotropy in GSTAT is it sufficient to use, in the kriging, a variogram model fitted with an alpha factor equal to the two directions? Many thanks, Fabio
Fabio, the alpha parameter value should be set to one of these two directions, but the tol.hor parameter should be very small, close to zero, to really obtain the information for this direction. This works, in practice, only for regularly organized (e.g. gridded) data. I would, in practice, always look at multiple directions to check whether the data indeed reveal zonal anisotropy.
Fabio Veronesi Ph.D Student Cranfield University
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