Legal Header

Updated May 2022

The Cardium Formation has been prominent in Alberta since oil was discovered in the Pembina field in 1953. Since 2009, the AER has seen renewed interest in this formation, with horizontal multistage fracturing technology showing success in accessing previously inaccessible reserves in the tighter halo areas adjacent to the historically targeted higher porosity and permeable pools. Despite reduced drilling in today's environment, the Cardium Halo remains a target for new development in Alberta.

Figure R2.1 shows the extent of the Cardium Formation in Alberta and the location of the West Pembina assessment area.

Low permeability area in the Cardium Formation


The Cardium Formation was deposited in the late Cretaceous, over 86 million years ago, in mainly marginal and shallow marine environments. In the Pembina field, this formation is divided into two members: the Pembina River and the overlying Cardium Zone.

The lower Pembina River member is a shale-dominated offshore deposit. The upper Pembina River grades into sandier lithologies, deposited in shallow shelf and shoreface environments. Within the historically developed Pembina field, the sands of the upper Pembina River are often capped by conglomerate reservoir. The Cardium Zone is a muddy offshore deposit and is not a target for hydrocarbon production.

West Pembina Assessment Area

The Cardium Formation covers an area of about 170 000 square kilometres (25 per cent of Alberta). This report evaluates one assessment area within the Cardium Formation: the West Pembina assessment area. We chose this area based on similar geological characteristics and current development trends.

Depth to top of formation for the West Pembina assessment area ranges from 1500 metres (m) in the northeast to 2200 m in the southwest.

Most horizontal drilling in the Cardium Formation has been within the tighter areas of the West Pembina assessment area, with 17 horizontal gas wells and 993 horizontal oil wells.


The estimated total remaining proved plus probable reserves are

  • 8.2 million cubic metres (106 m3) oil,
  • 1.1 106 m3 NGL, and
  • 6,659 106 m3 natural gas.

The evaluation of reserves in this section is limited to horizontal multistage fractured wells completed within the Cardium Formation.

Table R2.1 shows the initial and remaining reserves for the low-permeability resources in the West Pembina assessment area of the Cardium Formation.

Initial and remaining reserves for low permeability resources for the Cardium West Pembina

Learn More