TransGen Version 3.2 includes new functionality to model user-defined and stochastically generated fault zone structure and to include the effects of these sub-resolution geometrical fault characteristics in the flow simulator.
The main innovations are:-
- Inclusion of the effects of user-defined faults not included explicitly in the geometry of the simulation model.
- Inclusion of uncertainty in fault throw or of local geological drag on faults included explicitly in the simulation model.
- Inclusion of fault relay zones and other forms of locally-paired slip surfaces on faults included in the input model as single surfaces.
The geometrical and fault rock effects of these features are exported as transmissibility or transmissibility multiplier files by TransGen, for direct inclusion in the simulator, allowing an implicit representation of more complex geometry than is represented explicitly in the model.
NOTE:- The new geometrical functionality operates only on single-phase properties. A TransGen run which includes both the implicit geometrical functionality introduced in this version and the two-phase functionality introduced in the Version 3.1. will run successfully, but will be internally contradictory, since the two-phase functionality is applied exclusively at the resolution of the input model. Combining the two sets of functionality is therefore not recommended.
The new functionality requires a separate license and is accessed by selecting
Include fault drag and hierarchical zone effects on the
Title page of
WizGen in Flexible Project mode. Much of the new functionality is associated with a new type of TransGen object called a faulted
trace (see section on
Traces and Fault zones below for details).
Other Changes to TransGen since Version 3.1
The only other unrelated changes have been made to the
WizGen Miscellaneous Options page where the
Lower limits box has been modified. It now contains three constants, each of which defaults to the value of 1.0E-6 . These are:-
Unfaulted transmissibility cut-off (keyword TGMINTR)
Cell volume error tolerance (keyword TGVOLERR - associated with identifying geometrically corrupt cells)
Cell pore volume cut-off (Keyword MINPV)
MINPV was not accessible in the previous version, and TGMINTR was incorrectly described as a "multiplier cut-off". TransGen will render inactive any cell with a pore volume less than the specified MINPV value and will ignore any connection with an unfaulted transmissibility value less than the specified TGMINTR value. The default values follow those in
Eclipse, which considers any cells with pore volumes greater than 1.0E-6 to be inactive and does not consider connections to be present if their transmissibilities are less than 1.0E-6 .