Free convection or variable density flow within groundwater flow systems?
K.U. Weyer and J.C. Ellis
Paper prepared to accompany a poster presentation at IAH-CNC Waterloo, ON, Canada, Oct. 27 - 30, 2015.
© 2015, WDA Consultants Inc.
In northeastern Alberta, free convection has been postulated by Bachu et al. (1993) and Bachu and
Underschultz (1993) disguised as buoyancy-driven downdip flow in deep aquifers opposing gravitationallydriven
updip flow within groundwater flow systems. This postulate is based on the assumption that the
buoyancy of heavier fluids is directed vertically downward and then obliquely reflected downdip within the
bottom part of dipping aquifers on top of underlying aquitards. At first glance this concept seems to be
reasonable and could thereby be handily applied to determine the fate of saline water as subject to
downdip flow directions, while lighter fluids such as hydrocarbons or sequestered CO2 would be subject to
buoyancy-driven updip flow moving along the upper parts of aquifers underneath an overlying aquitard.