Open File Report 1987-05

Open File Report 1987-05

OFR 1987-05

Estimate of Inferred Resources of Coal in the Plains Region of Alberta to a Depth of 400 Metres

In the plains region of Alberta, major deposits of mineable coal are present in three geological units: the Ardley coal zone, the lower Horseshoe Canyon Formation and the Belly River Group. Since 1979, the Alberta Energy and Natural Resources has had a contract with the Alberta Research Council for a coal evaluation program of the Alberta plains. Major objectives of the program are met by separate reports detailing the geologic character of each unit, and include sets of resource maps and representative cross-sections. This report describes the size of resources for each unit.

Coal resources have been calculated from a computer database. The database consists of information obtained from wells drilled by the oil and gas industry, and wells drilled by the Alberta Research Council. The size of resources is represented in a graph form. Curves plotted on each graph give the total size of resource for minimum seam thicknesses between 0.5 and 4.5 m. Generally, the thicker the minimum seam thickness, the lower the coal resource calculated because fewer seams and fewer townships can be used in calculations. Representing resources in this manner allows for easy comparison to coal resources of other areas.

Present calculations are for resources from near surface to a depth of 400 m. With a distribution of 2 to 3 wells per township (100km�), these calculations are considered to fall under the category of 'inferred resources'. The Geological Survey of Canada regards coal seams over 1 m thick in the Alberta and Saskatchewan plains as being of 'future interest' if they are shallower than 450 m. On this basis, inferred resources of the Ardley coal zone, the lower Horseshoe Canyon Formation and the Belly River Group are calculated as 105 billion tonnes, 125 billion tonnes and 93 billion tonnes respectively.