MultiFolder

Overview

A MultiFolder block model is designed for deposits with multiple layers (envelopes), where a single block can be intersected by more than one envelope.

It follows the same general creation workflow as a regular block model, but instead of selecting one envelope, you select multiple envelopes.

For reliable results, envelopes should be valid and should not cross each other. Crossing envelopes can produce invalid or excessive total block fractions.

When to Use MultiFolder

MultiFolder is typically used for multilayer deposits such as:

• stratiform deposits
• strata-bound deposits
• layered sedimentary deposits

Use it when each layer must be treated and estimated separately, while still keeping one parent block model.

Create a MultiFolder Block Model

1. Start a new block model.
2. In envelope selection, choose multiple envelopes.
3. In block model type selection, choose MultiFolder.
4. Set percent/fraction precision options as needed.

In MultiFolder mode, percent calculation is enabled automatically.

What Is Created Automatically

After creation, the schema is expanded automatically:

• each selected envelope gets its own grade variable(s)
• each selected envelope gets its own classification field
• each selected envelope gets its own percent/fraction field
• combined calculated variables are created on the parent model

Example with one variable (Cu) and three envelopes:

• fold variables like Cu_Zone_A, Cu_Zone_B, Cu_Zone_C
• percent fields like Percent_Zone_A, Percent_Zone_B, Percent_Zone_C
• a combined calculated Cu value on the parent model

The combined value is a weighted average using fold grades and fold percentages.

Views for MultiFolder

You can create one view per fold using Edit > Create View Automatic… with MultiFolder View enabled.

This is very useful to:

• separate folds
• run estimation by fold
• prepare fold-specific resource reporting

General behavior:

• one view is created per selected fold
• each view keeps only the fold-relevant fields (plus shared required fields)
• a block can appear in more than one fold view
• total block fraction across folds should not exceed 1

In practice, fold views are usually simpler and faster to display than the full parent model.

Estimation Strategy

Estimation is similar to regular block model estimation, but done per fold variable.

You can:

• estimate fold views independently, or
• estimate from the parent model with fold-specific settings

A common workflow is to estimate using fold views, then use parent combined variables for global reporting.

Resource Reporting

For resource reports, you can:

• report on the parent combined variable (final blended block value), or
• report on fold views for per-fold results

Report export supports common file formats (Excel, HTML, TXT, CSV), and reports can be opened immediately after generation.

MultiFolder Operations (Block Model List)

From the MultiFolder menu, the following commands are available:

• Manage… Review which variables are linked to which envelope, and adjust links when needed.
• Cap Percent… Apply envelope priority to cap fractions when total percent is too high (for example after overlap or precision effects).
• Add Envelope… Add one or more envelopes to an existing MultiFolder model; required fold variables and fractions are generated automatically.
• Remove Envelope… Remove selected envelope(s) from an existing MultiFolder model.

Important Note on Remove Envelope

Removing envelope(s):

• removes associated fold variables
• removes blocks that belong only to the removed envelope(s)
• removes associated views

This action is not intended as a temporary operation. Create a copy of the block model first when you need a safe rollback path.

Good Practices

• Validate envelopes before building MultiFolder.
• Avoid envelope crossings whenever possible.
• Use fold views for day-to-day estimation workflows.
• Keep parent model variables for consolidated final reporting.
• If percent totals exceed 1 in some blocks, fix geometry first, then use Cap Percent… if needed.