Marco Air computes the response of 3D prisms contained in a multi-layered host. Figure ld illustrates the Leroi Air class, which is designed to model structures composed of multiple, fully interacting thin sheets, encased in a uniform host overlain by a uniform overburden. This model can be used for very large conductivity contrasts. Another product developed by the Centre is Airbeo, an AEM layered-earth inversion program for both frequency and time domain which is up to 20 times faster than conventional inversion techniques. Inverting to a two, three or four layer model can be useful in its own right or, alternatively, provide a very useful first look at AEM data before deciding on more complex interpretation techniques.
Programs are useful only if they are used.
Encom Technology worked with the Centre to develop Milsons, a GUI specifically designed for the 2D and 3D mesh programs. Using wizards, Milsons initially helps the user set up a simple mesh as illustrated in Figure 2. The user is then able to use the mouse based tools to develop the more complex structure illustrated in Figure 3. Milsons then supplies dialog boxes to set up system geometry, waveform and flight path as shown in Figure 4. The 3D option of Milsons, which will be released shortly, allows the user to rotate the 3D model to view it slice by slice, in chair mode, or as a wire frame where only those parts of the model with a specified range of properties are shown in colour.