Abstract

The basic question which this thesis seeks to answer is: ‘Was the baseflow which flowed continuously in Lockyer Creek prior to 1980 outflow from adjacent alluvial aquifers, or was it outflow from basalt aquifers on the Main Range?’ This question was not obvious at the start of the project when information from ‘official sources’ suggested that Lockyer Creek was ephemeral, and there was no baseflow. To answer this question, it was necessary to define baseflow (as outflow from aquifers) and to devise a means of separating it from overland flow, because the existing methods separate ‘quick flow’ from ‘prolonged flow’; not overland flow from baseflow. The existence of baseflow presumes the existence of aquifers in the catchment, so geology of the catchment was examined to identify its aquifers.