Adding a depth-dependency to fault-permeabilities
In earlier versions of TransGen (i.e. pre the Version 3 release) the
TGKDT keyword was used to add a depth dependent variation to fault-rock permeabilities. For all later versions, such depth-dependency can be added via the
PERM plugin (
i.e. using the PERM Function on the
User-defined plugins page of
WizGen in "Flexible project" mode). This allows the effects of diagenesis or pressure solution to be easily included.
How to modify fault properties by region
One way to modify the fault properties in a region of the model is by using the
BOX keyword to simply modify the fault permeabilities in a region of the model by a permeability multiplier specified using the
TGKDT keyword. Click
HERE for a worked example. Restricting the 'BOX' to specific layers and using it with a the TGKDT permeability multiplier is a good way of adding the effects of cementation by juxtaposition against calcite or halite bearing beds.
Alternatively, different fault-permeability / SGR relationships (set by the
TGKSE or
TGKDT keywords) in one area of the model also using the BOX keyword. Other different approaches include using the
BOX,
ADD,
MULTIPLY or
EQUALS keywords to modify the
NTG or
TGVS data locally, and hence modify the predicted fault properties. This works well if only certain reservoir/ reservoir juxtapositions need to be modified.