Processing On: This checkbox controls if the grid file
will be created when the Make Grids button is clicked. If
the grids take a long time to process and only some grids need to
be processed, you can toggle this option to avoid making every grid
file.
Filter Data By Elevation: This option will filter data
points outside of the Min Z and Max Z range.
Choose Strata to Process: This button will allow you to
select the strata/bed and attribute to model in the grid file. The
primary difference between selecting strata in the Make Strata
Grids command and selecting strata here is that this command allows
you to select multiple strata/beds at the same time. However, you
may only create one attribute for the selected strata. For example,
if you select five strata to model, you will not be able to select
the elevation and the thickness attribute at the same time.
Instead, you will have to define the five elevation grids and then
repeat the process to define the five thickness grids. Also, when
multiple strata are selected, you will only be able to select
attributes that those strata have in common.
When selecting multiple strata, you will also be prompted if the
strata should be composited or if separate grids should be made for
each strata layer. When strata attributes are composited into a
single grid file, the attribute will be weighted by the thickness
of the strata. Attributes that require averaging based on the
weight of the material should be composited using Grid File
Utilities.
After selecting the strata and attributes to model, you will be returned to the above dialog to set additional parameters for the grid(s). The attribute to be modeled and the first strata selected will be shown to the left of the Choose Strata to Process button.
Set Grid Position: This button will set the dimensions
and extents of the grid cells. After setting the grid position
once, all other grids in the autorun file will default to use the
same position and cell sizes.
Choose Grid File: This button will set the name of the
grid file. The program will automatically name grids with the
following format: "Strata_Attribute.grd". For example, a file named
"Overburden_Elv.grd" represents the bottom elevation of the
Overburden strata. The below attribute names are used by
default:
- _ELV - this suffix is used for bottom elevation grids
- _EL2 - this suffix is used for top elevation grids
- _THK - this suffix is used for thickness grids
- User-defined attributes will list the full attribute name in the grid file name
Use Pinchout Data/Use Seam Stacking/Conformance
Data: These checkboxes control if pinchout and conformance
logic will be applied to the grid file. However, this logic will
only be applied if it is also enabled under Settings Pulldown Menu
> Carlson
Configure > Mining Settings. This allows you to quickly
enable and disable pinchout and conformance data for select
grids.
Modeling Method: Most of these methods are discussed in
the section of the help manual corresponding to the Make Strata
Grids command. However, the 3D kriging option is discussed in
the Make
Block Model command.
Apply Extrapolation: This option will extrapolate the
grids where null values exist due to an inadequate search radius or
inherent limitations by the modeling method. When a value is
extrapolated, the data point at the edge of calculated values will
be carried into the uncalculated area. This prevents continuation
of slopes in the grids, as shown below.
Use Global Extrapolation: This option extrapolates the
grids where null values exist, but unlike the Apply Extrapolation
option, this option will search for localized slopes in the grid
file and attempt to carry the slopes into the uncalculated area.
This is shown in the below image.
Max Triangle Length: This value sets the maximum triangle
length for the Triangulation and Polynomial modeling
methods.
Search Radius: This value sets the maximum search radius
for data points. For example, if this value is set to 10,000, any
data points beyond 10,000 ft/meters from a given grid node will not
be used to estimate the value of that grid node. This concept is
shown in the below image.
Max Samples: This value sets the maximum number of data
points to use to estimate the value at a grid node. The data points
nearest the grid node being calculated will be used to estimate the
value at that grid node.
Min/Max Quadrant: When the program calculates the value
of a grid node, the area around the grid node is divided into four
quadrants, as shown below. These Min/Max Quadrant values set the
minimum/maximum number of data points to use from each quadrant.
This concept is shown in the below image. If the Min Quadrant value
is set to 5, a value will only be assigned to the grid node if at
least 5 data points are found within all four quadrants. If the Max
Quadrant value is set to 20, only the nearest 20 data points in
each quadrant will be used for estimation.
Use Parameter Filter: This option will filter data
points according to parameters as set in the Define
Parameters command. The parameters may be set by clicking the
Set Parameters button.
