Hydrochemistry Highlights Potential Management Issues for Aquifers and Springs in the Lake Blanche and Lake Callabonna Region, South Australia

Abstract

A hydrochemistry-based study has highlighted potential management implications for selected aquifers and springs located within the Lake Blanche and Lake Callabonna region in the far north of South Australia. The interpretation of hydrochemical and environmental tracers from 14 springs and 17 water wells, as well as historically available data, were used to establish five hydrochemical-based aquifer types for the region:1. Fractured rock crystalline basement aquifer. 2. Patchawarra Formation (Cooper Basin) aquifer. 3. J-K aquifer (Algebuckina Sandstone, Cadna-owie Formation and lateral equivalents) of the Great Artesian Basin. 4. A sandstone unit or units interpreted to occur within the Neocretaceous Rolling Downs Group, which is informally termed the 'Rolling Downs Group sandstone (RDGS) aquifer'. 5. Cenozoic aquifer.Two key findings from this study have potential implications for ongoing resource management. First, artesian groundwater conditions were identified for the first time within sandstones found within the Neocretaceous confining layer (the RDGS aquifer). Although the exact stratigraphic nomenclature of this sandstone unit is not yet confirmed, groundwater sourced from this unit is currently being used for stock. Second, the RDGS aquifer may contribute to spring flow at Lake Blanche and Lake Callabonna. Similarly, the fractured rock aquifer may be a source of water for the Petermorra Springs complex. Beyond certain results from these three spring complexes, the majority of hydrochemical and environmental tracer analyses infer that the J-K aquifer is the primary source aquifer supporting spring flow.

Springs of the great artesian basin – oases of life in australia’s arid and semi-arid interior

“…In the time since European settlement, studies dating back over 140 years testify to the dedication of individuals and agencies committed to documenting, researching and monitoring springs. Papers in this volume provide comprehensive reviews of the hydrogeology and hydrochemistry of GAB springs, their modes of origin, the geography and biophysical attributes of springs, and understanding of processes needed to inform management and recovery of GAB springs affected by groundwater use and drawdown (Habermehl, 2020;Flook et al, 2020;Keppel et al, 2020). Recent surveys are still yielding new information in the less well-studied parts of the GAB, such as the Mulligan River Springs (Silcock et al, 2020), the only permanent surface water in this dry area on the edge of the Simpson Desert in far-western Queensland (Figure 1).…”