We have conducted a number of calibration and validation studies, where the output from Dynamic Fracture Model Generator was compared with fracture networks observed in outcrop or in the subsurface. Some examples are given below:
Nash Point, South Wales:
- A complex fracture network developed in thin limestone beds surrounded by ductile shales in response to deformation on larger strike-slip faults.
- We were able to replicate the observed fracture pattern.
- This work showed the importance of stress shadows and layer thickness in controlling fracture geometry.
Robin Hood’s Bay, NE England:
- Another network of fractures in thin limestone beds surrounded by ductile shales, this time in response to the km-scale Peak Fault
- There are two orthogonal fracture sets. In some areas, these form an isotropic fracture network, but in others, it is anisotropic with long primary fractures connected by short secondary fractures.
- This work showed the importance of modelling stress variations around the Peak Fault to predict anisotropy in the fracture network.
Kraka field, Danish North Sea:
- An offshore oilfield producing from a fractured chalk reservoir
- We were able to replicate the fractures observed in borehole imaging, by modelling fracture growth due to salt diapirism and deformation on seismic-scale faults.
- Similar studies carried out on other producing chalk fields (e.g. Gorm, Svend) were used by DUC partners Total and Noreco to improve flow models.
Drenthe structure, onshore Netherlands:
- A salt diapir underlying interbedded sandstones, shales and chalk strata
- Considered as a potential geothermal energy source.
- Fractures are important in controlling subsurface flow.
- Regional seismic survey and some well data available, but no core or borehole images.
- Used as a case study for modelling fractures in data-poor exploration prospect.
