In this blog, we will demonstrate how to use the Combined Models functionality to model any categorical data so you can visualise relationships in your project.
Did you know that the ‘Geological Models’ folder in Leapfrog Geo is not just for modelling geology? Any categorical data available within your project can also be modelled. This could be in the form of a water table, pit shell or in the example we’ll give here, tenement boundaries. A challenge every mining company faces is assessing the value of not only the economic orebody on their tenure, but also the potential on neighbouring tenements.
So how can we begin assessing this at an early stage? Through the use of Leapfrog Geo’s Combined Models!
Explore this workflow as a fully interactive model using Seequent’s free sharing and collaboration tool, View:
In Leapfrog Geo, a Combined Model uses the volumes from multiple geological models, interpolants and distance functions in order to visualise relationships between different types of data in the project. For example, you could combine a geological model with an interpolant to see what lithologies higher grades are occurring in.
We will begin by creating a geological model using a tenement boundary. In this project, we have a series of drillholes across two mining tenements. In the image below, those displayed in red have been drilled by My Company, and those in blue by a joint venture (JV) partner. The boundary for our tenement is displayed in orange.
To set up the model, right-click on the ‘Geological Models’ folder and select ‘New Geological Model’.
The ‘Base lithology column’ is set to ‘None’ and the extents to match the geology model.
We also need to create additional lithologies to represent the tenure: ‘My Company’ and “JV’. Double-click ‘Lithologies’ and select ‘Add’ to populate additional lithologies.
Next, we need to turn our tenure boundary from a GIS line to a surface. Right-click ‘Surface Chronology’, select ‘New Deposit’, then select ‘From GIS Vector Data’.
We want to select our tenure boundary here. It is important to make sure the correct lithology (My Company and JV) is accurately assigned to the mesh. This can be reviewed in the scene view.
Once the surface has been made, double-click ‘Surface Chonology’ and activate the surface.
We now have two volumes that represent My Company’s tenure and the JV tenure.
The last step is to create the Combined Model. Locate the ‘Combined Models’ folder in the project tree and select ‘New Combined Model’. In a Combined Model you can combine the volumes of up to three different categoric and numeric models. In this case we will use the two models in the ‘Geological Models’ folder.
Select the tenure and geology models to combine by ticking them in the first dialog. This could also be a numeric model if desired. The order in which you combine the models will dictate which model is cut by the other. In this case, we want our geology model to be cut by the tenure model. For this we need the tenure model to be at the top. Use the arrows to re-order the models and tick the volumes you want to combine; in this case we will tick them all. The geology can be viewed whole or individually per tenement.
In this example, the diorite is our economic lithology containing high-grade copper and gold. A simple way to see the volume of this lithological unit is to select the mesh in the scene view. The properties window in the bottom left hand corner displays the volume for this mesh.
A Combined Model is simple to create and will dynamically update as you add additional drilling. This allows you to stay up to date with the volume of your orebody.
Using the Combined Models not only allows you to use information outside of your tenure (where geology is contiguous) to create an accurate model of your orebody, but also assess the potential within and surrounding your tenement.
We can also take this one step further and use this information to refine our statistics or resource report in Leapfrog Edge, and determine potential mean grade and tonnage.
The tenure model can be evaluated onto a block model. To review the block model statistics by tenure:
- Right-click on the ‘Block Model/Sub-Blocked Model’ in the project tree.
- Select ‘Statistics’.
- Select ‘Table of Statistics’.
- Set the appropriate density.
- Click ‘Add’ twice to create two levels for your categorical data. Set tenure as ‘Level 1’ and geology as ‘Level 2’.
- Select the grade variable of interest in the ‘Numeric Items’ section.
Have you used Combined Models before? We love to hear from our users, so please feel free to share your ideas and comments below.
As always, you can reach out to our regional technical support teams with any questions.