This study and others have examined the hydraulic connectivity between aquifers within each of the two layers and between the two layers. Various data was used, including stratigraphic relationships, lithology, pumping tests, groundwater levels and groundwater chemistry. It is concluded that the CLA forms a single aquifer system in which the two layers are hydraulically connected to some degree, especially in the Georgina Basin. The Upper CLA has a significantly lower vertical hydraulic conductivity than the Lower CLA. The aquifers range from being unconfined to confined depending on the type and thickness of cover material. In the majority of cases they are semi-confined.
Current connectivity between the CLA and deeper aquifers is based on subsurface geological relationships determined by deep drilling, seismic surveys, sub-surface mapping, geomorphology and detection of 3He in groundwater. Available data has been used to map formations directly underlying the CLA and so highlight areas of potential connection.,
Notes
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Table of contents
1. Executive Summary - 2. Introduction - 3. Literature Review - 4. Geology - 5. Hydrogeology - 6. Aquifer mapping and spatial files - 7. Discussion - 8. Recommendations for further investigation - 9. References,