Northwest Alberta is characterized by high subsurface temperatures that may represent a significant geothermal resource. In this abstract we present new data that allows us to make predictions of the temperatures that might be found within the crystalline basement rocks. In this region the WCSB is composed of up to 3km Phanerozoic sedimentary rocks that acts as a thermal blanket owing to the low thermal conductivity of the sedimentary rocks. Commercial well-logging data was cleaned of erroneous data and corrected for paleoclimatic effects to give average geothermal gradient of 35 K per km and maximum geothermal gradients reaching 50K per km. These and thermal conductivity model of sedimentary rocks were then used to estimate heat flow across the basement - WCSB unconformity assuming heat generation of 0.5 µW/m3 within the sedimentary rocks. Estimation of temperatures within the crystalline basement rocks requires knowledge of the thermal conductivity (TC) and heat generation (HG) of these rocks. These are mainly granitic Precambrian rocks. Thermal conductivity (TC) and heat generation (HG) of the basement rocks were measured in samples recovered from hundreds of wells that sampled the Pre-Cambrian basement rocks. TC values were corrected for pressure and temperature variation. Using these data, we have developed a temperature model of northern Alberta which predicts temperatures in the 3-6 km depth range. Analysis of the temperature variations in NW Alberta has resulted in the discovery of the Rainbow Lake high temperature anomaly. The heat flow below the sedimentary cover ( > 2 km) at this location represent the highest heat flow in Alberta. This is the hottest spot found in Alberta at these depths. Temperature model predicts high temperatures (>170°C at 4 km depth and >200°C at 5 km depth and as high as 230oC at 6km) within the Precambrian (Pc) basement rocks in Northwest Alberta. Since this temperature anomaly is located within crystalline basement rocks, an Engineered Geothermal System (EGS) would be required to utilize this heat. A geothermal reservoir created at 5 km depth could theoretically produce about 20 MW thermal energy and 2 MW electrical energy from a doublet system with 30kg/s flow rates. The creation of an EGS in this location owing the presence of naturally occurring fractures within the Great Slave Lake Shear Zone.

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