Geoscience Reference
In-Depth Information
this purpose. Consider a number of sensitiv-
ity runs with different slice thicknesses and
other parameters. Plot the results. Comment
on the presence of a vertical trend and the
importance of considering it in the simula-
tion model. Present the inal result that you
choose.
Question 2:
Calculate the vertical average of the drillhole
data, make a map of the vertical averages, and
comment on the need for modeling the areal
trend.
Generate a smooth areal trend using kriging,
inverse distance, or the contouring approach
used in Part One.
Question 3:
Construct a 3-D trend model by combining
the 1-D vertical trend and the 2-D areal trend.
Comment on the practical implications of the
conditional independence assumption implicit
to the combination approach commonly used.
Also comment on the alternatives to construct
a 3-D trend.
Question 4:
Calculate residuals as
res = grade
−
grade
trend
. Plot a histogram of the residuals. Plot
a cross plot of the residuals versus the
grade
trend
values. Comment on any features that
would make it awkward to simulate the grade
residuals independently of the grade trend.
References
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