Assigning a modeling method

With the Assign Method form (model > Rock Properties > Assign Method), you specify a modeling method to populate your 3D grid with rock properties. You assign a method to each one of your Volumes of Interest (VOIs), i.e. the sub-sets of your 3D grid, one by one.

Volume of Interest (VOI)  A sub-set of your 3D grid. It allows you to populate your 3D grid with rock properties by modeling each VOI separately.

Defining VOIs  You define your VOIs based on the selections you make on the Create Model form, under 'Volume definition' and 'Nest within'.

Going through the workflow on a per-VOI basis  It is recommended to take each VOI one by one through the workflow. You start with assigning a modeling method to one VOI. Only once you have completed defining the model parameters for one VOI, you should proceed with the next VOI. This lets you to focus on each VOI separately, analyze its data and fine-tune its modeling parameters. At the end of the workflow, you can run your model in parallel for all or only certain VOIs you selected.

Workflow steps  Since each modeling method has its own specific set of modeling parameters, the workflow will automatically take you to the next relevant step. Some steps might be skipped depending on the method you selected or the data you have.

Rock property model  The container which holds all the associated metadata: upscaled property, volume definition (i.e. VOIs), modeling method and modeling parameters per VOI, etc.

Rock grid property  The resultant grid property, which is a combination of all modeled VOIs. Once you have run your model, it will be available in the JewelExplorer (3D Grids > Your 3D Grid > Properties > Rock Properties > Your Rock Grid Property). It is read-only and has the same name as the rock property model.

To assign a modeling method

  1. Open the Assign Method form and select the rock property model from the Model drop-down list.
    2. You can hover over the factsheet icon () next to the drop-down list to check the key inputs (e.g. 3D grid, upscaled property, volume definition) to the rock property model you have selected.
  2. Select a Volume of Interest (VOI) from the table on the left side of the form.
  3. Under Method, select the modeling method that you want to apply to the selected VOI.
    4. You can also copy-paste the modeling method from one VOI to another VOI using the context menu options Copy - Paste (to paste to one VOI) or Copy - Paste Method Options (to paste to multiple VOIs at once). The last option opens a separate form on which you can check the boxes for all VOIs that you want to paste to. Note that checkbox selection can be done in bulk by holding down SHIFT while selecting a range of VOIs (they turn blue), then checking the box of one of them. All other VOIs in the selected range will get checked simultaneously.

    With the Paste Method Options form, you can paste a copied method to multiple VOIs, i.e. target VOIs, at once. The grayed out boxes at the top of the form display information about the Input VOI from which you have copied the method. Subsequently, check the boxes for the Target VOIs to which you want to paste the method. When you are pasting the method, you have the following options regarding the modeling settings (e.g. all settings that you set during the various steps of the workflow, i.e. variogram and transformation settings, conditioning and settings on the 'Control Method' form).

    • Restore previous settings  This option is applicable to target VOI(s) that previously had the same method as the Input VOI. By using this option, you can restore those previous settings, so that you do not need to re-define them.
    • Keep current settings  This option makes sure that while you are pasting a new method, any overlapping settings (i.e. similar settings for the Input method and the current method) are kept. For example, if you copy-paste SGS to a VOI that currently has Kriging and you choose 'Keep current settings', the variogram (which is applicable to both methods) will be kept. Note that non-overlapping settings will be empy.
    • Clear settings  This option is a fast way of assigning a method with no settings. You can use this option, if you have many VOIs to which you want to assign the same method.

    Paste method options    click to enlarge

  4. Click Apply to assign the method(s) and keep the form open, or click OK to assign and proceed to the next step.

Rock property modeling methods:

This selection assigns a constant value to all the grid cells within the selected VOI.

This selection uses the inverse distance-weighted algorithm to interpolate the property across the 3D grid. Select one of the pre-defined settings for the weight that the algorithm will apply in the Parameters column.

This selection applies the geostatistical Kriging method to interpolate the property across the grid cells.

SGS is a stochastic modeling method which is able to reproduce the desired target distribution.

For any of the methods you select, later on you can choose to overwrite or not to overwrite the upscaled properties at the well locations, i.e. the blocked wells. This option is available on the Control Method form as a checkbox 'Ignore well locations(s) for output'.
  • If you check this box the upscaled properties at the well locations will be overwritten.
  • If you do not check this box the upscaled properties at the well locations will not be overwritten.