Triangulated surfaces are often the foundation of modeling a mineral deposit. Whether the surface is current topography, a fault plane or a thickness isopach an accurate surface is an integral part of the model. Creating this surface should be simple and easy, but in Vulcan there are so many options. Where do you start? This tutorial shows you how to create a simple surface triangulation in Vulcan and touches on some of the options you may want to use during creation.
Creating a surface triangulation begins with the input data. This data can be a topography map with strings at actual elevation or a set of points like drillhole collars or grade values. The data should be loaded in Vulcan and displayed in Envisage. Create the triangulation using the menu Model > Triangle Surface > Create. The panel that pops up will have several tabs, each with many buttons and checkboxes. This is a good time to introduce the second rule of Vulcan “When in doubt, accept the defaults.”
Vulcan is usually pretty good about putting thought into the default settings. Creating a triangulated surface is no exception, selecting the default settings will create a simple, standard triangulation. After clicking the ‘OK’ button you will be prompted to select the data to triangulate. Select the data to triangulate (usually by layer or group) and cancel out of the ‘Select By’ panel.
In the ‘Triangulation model name’ panel type in a name for the triangulation (the extension .00t will be added automatically) and specify a directory in which to save the triangulation. The default directory is the working directory and is a safe and easy to find location. Before you finish be sure to specify a color. Click on the Primary colour tile and select a color. If you leave all your triangulations the same, default color they will be extremely hard to work with. Click ‘OK.’
That’s it. You have just created a Vulcan surface triangulation. It can be used to create a model, Boolean new shapes or just to look good with your mine design. Now that you are done, there are a couple of other options that you might want to look into the next time you create a triangulation:
Boundary – the boundary tab is for surfaces whose boundary is not mainly circular (like the shape of the state of Utah). This option limits the extents of the triangulation to the boundary instead of allowing triangle facets to bridge the gap. If the boundary is at the correct elevation select ‘Use boundary polygon as part of triangulation data’ if the boundary is at an arbitrary elevation select ‘Relimit triangulation with boundary polygon.’
Condition – this option prevents the formation of certain edge triangulations. These manifest themselves mainly as vertical walls at the edge of topography, effectively making your surface into a bowl. Select ‘Maximum edge length’ and enter a value of the longest edge triangle side that is allowable. This value will vary from surface to surface but in a mine design it is unlikely that it will be less than 100 feet or meters.