| The natural gas reservoir of the Pine Creek Field lies exclusively within the Normandville Member of the Stettler Formation, in the Famennian Wabamun Group.; Diagenesis of the Normandville Member is marked by the formation of calcite cements, selective and pervasive replacement dolomite, dolomite cements, replacement anhydrite, and sulphide minerals.; The Normandville Member carbonates are depleted in delta18O (range = -6.25 to -11.31‰ for calcite and -3.13 to -11.65‰ for dolomite). delta13C values are slightly within the postulated range of values for Devonian marine carbonates, except for late calcite cements that have low delta13C values (range = 1.54 to -26.33‰), due to incorporation of carbon-12 from sulphate-hydrocarbon redox reactions. Fluid inclusion data shows that these diagenetic mineral phases formed at a temperature range of 76.2 to 154°C. Salinity values for primary fluid inclusion range from 4.2 to 28.9wt% NaCl, showing that the parent fluids of the diagenetic minerals are evaporitic brines. (Abstract shortened by UMI.)... |
