Geosoft released VOXI two years ago, and since then geophysicists around the globe have run over 11,000 gravity and magnetic inversions using the service. These airborne and ground geophysical surveys are often accompanied by drillhole investigations as well. When it comes to inversion, additional information can constrain your model and improve your result.
Many of you are interested in incorporating susceptibility and/or density measurements from core samples but were stumped on how to build the VOXI constraint. In response to your requests, Oasis montaj 8.2 now has a simple model builder used to create parameter reference and weighting voxels from a drillhole database.
There are some important things to consider when using core measurements as constraints in inversion. For example, it is important that a background is removed from the core data so that it is consistent with the relative-to-background rock properties in the inversion result. Also, there shouldn't be an expectation that the constraint will yield a result that matches the core measurements exactly. After all, a 50x50x50m cell in the 3D model has a volume that is 1.6 million times larger than a 50m-long diamond drillhole core sample! It is far more valuable to expect the drillhole constraint to influence the relative distribution of the rock property within the model volume.
The new tool can be found in Oasis montaj 8.2 - watch the how-to video below.
Find these videos, and other how-to resources in the VOXI Learning Resource Centre.
Many of you are interested in incorporating susceptibility and/or density measurements from core samples but were stumped on how to build the VOXI constraint. In response to your requests, Oasis montaj 8.2 now has a simple model builder used to create parameter reference and weighting voxels from a drillhole database.
There are some important things to consider when using core measurements as constraints in inversion. For example, it is important that a background is removed from the core data so that it is consistent with the relative-to-background rock properties in the inversion result. Also, there shouldn't be an expectation that the constraint will yield a result that matches the core measurements exactly. After all, a 50x50x50m cell in the 3D model has a volume that is 1.6 million times larger than a 50m-long diamond drillhole core sample! It is far more valuable to expect the drillhole constraint to influence the relative distribution of the rock property within the model volume.
The new tool can be found in Oasis montaj 8.2 - watch the how-to video below.
Find these videos, and other how-to resources in the VOXI Learning Resource Centre.