Cardium Sand Model
The Cardium Reservoir
at Sundance comprises a blanket-like sheet of fine-grained, marine
sandstone. These reservoirs are typically capable of producing from 400
mcf/d to 1,000 mcf/d gas.
presence of low-angle thrust faults in the Cardium sandstone at Sundance,
as apparent on 3D seismic and from well-control, not only has the added
benefit of fracturing the reservoir to enhance permeability, but also
provides repeat occurrences of the Cardium – essentially doubling the
overall pay thickness.
The permeability of the
Cardium sandstone can be significantly enhanced by secondary fracturing
produced by the compressive stresses related to the low angle thrust
faulting. These naturally occurring fractures generally are parallel to
the thrust plane and can often be many kilometers long. This fractured
sandstone is very suitable for "fracing" to greatly improve
productivity. Fracture enhanced Cardium wells can typically produce 2,000
to 6,000 mcf/d.
The faulted Cardium reservoirs can be delineated by 3-D seismic. In most cases 4 wells per section can be drilled – providing a significant increase in production.