Nested Variogram Model for 3D data using gstat

Dear All,

 

I am facing problem to obtain the nested variogram model for the 3D
lithological data. I have 3D data, in which the coordinate are x,y,z (z
corresponds to the depth) and the lithofacie information for different
materials as a binary values (Ind01, Ind02, Ind03, Ind04, Ind05) . Now I
would like to develop sequential indicator simulation to obtain the
facies distribution for each of the category. I have used gstat to
develop the vertical and horizontal varigram but unable to fit as a
nested variogram for both vertical and horizontal direction. Is there
any one help me to combine the vertical and horizontal variogram in one
nested structure.

The data I have used from the greengoblin data. A dropbox link has been
placed at the end of this post to obtain the data.

 

The code I have used as follows to obtain the vertical and horizontal
variogram for the Ind03 facies (medium sand)

green_gstat <- as.data.frame(green_goblin)

coordinates(green_gstat) = ~X+Y+Z

names (green_gstat)

class(green_gstat)

# vertical variogram

ind03_vert <- variogram((Ind03)~X+Y+Z, green_gstat, cutoff = 250, width=
2, alpha= 0, beta = 90)

# fitting the variogram model

ind03_fit <- fit.variogram (ind03_vert, vgm(1, "Exp", 500,1))

# plotting

plot(ind03_vert, ind03_fit)

Rplot01

# estimating the horizontal variogram in omni direction

Ind03_hori_omni <- variogram(ind03, cutoff = 15000, width = 1000, alpha = 0)

# fiting variogram mdoel

ind03_fit_dir <- vgm(.188, "Exp", 1500, .05, anis = c (45, .25))

# obtain the fit model informaiotn

Ind03_fit_vrio_hor <- fit.variogram(Ind03_hori_omni,vgm(.188, "Exp",
1500, .05, anis = c (45, .25)))

# plotting the data

plot(Ind03_hori_omni,ind03_fit_dir)

hori

# now I have tried to go for the nested variogram approach, typically
what I have found there, that one can create the nested model like this
from the same variogram, but using diffent fitting options.

ind03_vertnested <- fit.variogram (*ind03_vert*, vgm (1, "Exp", 500,
add.to = vgm (.188, "Exp", .05, anis = c(45, 0.25))))

here I have only used the ind03_vert (variogram), but I also have a
horizontal variogram model (Ind03_hori_omni). So, how I can incorporate
two model into a single variogram model. A feedback in this regard would
be highly appreciate. Or, is there any other option to create a 3D
variogram modeling.

 

To have the data, please follow this dropbox link for the easy access.

 

Link to the data-
https://www.dropbox.com/s/6xl8zh7ofntlna6/GreenGoblin.csv?dl=0

 

 

 

 

*--*

*A.B.M Firoz*
*Researcher- GIS & Hydrological Modeling*

* *

*ITT*- Institute for Technology and Resources Management

in the Tropics and Subtropics

*Technology* *Arts** **Sciences*
*TH K?ln* - University of Applied Sciences 

 

T:  +49 221 8275-2059

F: +49 221 8275-2736
E : abm.firoz at fh-koeln.de <mailto:abm.firoz at fh-koeln.de>

 

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