Simple reblocking
The BM REBLOCK function allows you to take a model with a certain user block and minimum block size, and create a new model with different block sizes. It is also possible to use this function to regularize the model to a given block size.
To run this function: Choose Block model > Block model > Simple reblocking, or...
This function reblocks to a block size that may be larger than the blocks that exist in the model. If this is the case, then the attribute values from the smaller blocks are used to calculate the attribute values for the large block. This calculation is usually some form of volume weighted average, although it is possible to get the most often used values, all values or a number of other options. See the table below for more details.
Note: It is important that you define numeric attributes that should not be averaged during reblocking as calculated attributes. For example, tonnage should be defined as a calculated attribute based on block size and density, with the generic formula tonnage = _xext x _yext x _zext x sg.
Output Model Name
This is the name of the model that will be created to contain the results of the reblocking. The current model will not be changed in any way.
Description
This is the description of the new model.
Reblocking Type
There are two types of reblocking.
- Standard Reblocking allows you to reblock the model to a block size that is any super block size of the existing model. For example, with a block model that has a minimum block size of 1x1x1, legal values are 2x2x2, 4x4x4 etc.
- Advanced Reblocking allows you to reblock to a block size that is any integer multiple of the minimum block size. For example, a model with minimum block size of 1x1x1 can reblock to a block size of 10x5x2. However, 10x5x2.5 is not a legal size because 2.5 is not an integer multiple of 1.
Advanced Reblocking gives you much more flexibility, but will be much slower than Standard Reblocking.
New User Block Size
This section of the form allow you to enter the new user block size. Reblocking will always take place to this size. Depending on the reblocking type, this section of the form will modify itself to display the available options.
New Minimum Block Size
Allows you to determine the minimum block size for the new model. This will have no effect on this function, but will change how you interact with the new model. Please make sure that you've correctly filled out the New User Block Size section of the form to make sure that the values in this box are correct.
SG Attribute
All attribute values are weighted by volume to find out the correct value for the new block being created. However, in some instances, the best way to weight values is by tonnage. This field allows you to enter an optional Specific Gravity attribute to allow the weighting to occur on tonnage rather than volume. This Specific Gravity attribute acts as the global value for reblocking but can be overridden as required for each individual attribute by using the Specific Gravity column in the table.
Attribute Name
The name of the attribute to import or not. You cannot modify this value
Attribute Type
The type of the attribute. This is for informational purposes only - you cannot modify this value.
Include
You do not have to include all attributes from the current model in the new model. If you do not wish an attribute to appear in the new model, uncheck that attribute using this field. The attribute will have no active part in the calculation, and will not be imported into the new model.
Reblocking Method
There are several methods of assigning a value from the blocks in the old model to the blocks in the new model. The reason we need these methods is that it is very usual that the blocks in the existing model will be smaller than the blocks in the new model. Therefore, a group of blocks of various sizes actually make up the block we're filling. The methods of reblocking are different depending on the attribute type.
| Reblocking Type | Description | Attribute Types |
| Mode | Takes the modal (most often used) value as the reblocked value. | Character, Integer |
| Concatenate | Takes the attribute values and concatenates them into a single character attribute. If the attribute is of type integer, it will be automatically converted to a character if you select this type. An example of the output attribute would be something like ore|waste|rock | Character, Integer |
| Integer Mean | Takes the volume weighted mean of the values, and returns the integer average of the values | Integer |
| Real Mean | This takes integer values, and calculates the true mean of them. In the process, this method will convert an integer attribute into a real attribute | Integer |
| Minimum | Finds the minimum integer value. | Integer |
| Maximum | Finds the maximum integer value | Integer |
| Mean - negative values included | Calculates the true mean of the values, treating negatives exactly the same as positive values | Real, Float |
| Mean - negative values ignored | Calculates the true mean of the values, but will treat a block with a negative value as if the block did not exist. This will not add values to either the total value or the total volume | Real, Float |
| Mean - negative values as 0 | Calculates the true mean of the values, but will assume that a negative value is 0. This method will still include the block volume in the calculation, just not the block value. | Real, Float |
| Sum | Calculates the sum of the values. This method will not include the block volume in the calculation, it will simply sum the values of the attribute. This is useful when calculating the total tonnage for block model. | Real, Float, Integer |
Override SG Attribute
This column in the table is provided to allow the user to override the default Specific Gravity attribute specified for the calculation for this attribute.
Once reblocking is complete, the new model will be the currently loaded model.