Geophysical Characterizations of the Paskapoo Formation

Abstract

The petrophysical statistics of Paskapoo Formation lithologies were established from five Alberta Geological Survey boreholes after the lithologies were reclassified into a smaller set of groups. The study focused on gamma, density, resistivity, and sonic logs. Results show that 92 API and 19 ohm.m is the gamma and resistivity cutoff between sandstone and mudrock, and indicate that electrical resistivity method can be used to distinguish lithology of the Paskapoo Fm., while seismic refraction method has limited usage. Electrical resistivity and seismic refraction data were collected in a field site, Priddis, Alberta and processed to test the feasibility of the two methods to constrain the subsurface architecture. With the assistance from Priddis borehole and the combined interpretation of the two tomograms, results show the depth to the bedrock ranges from 5 to 10 m and heterogeneous upper part of the bedrock is dominated by sandstone and mudrock.