Bore yields for the Cambrian Limestone Aquifer - Beetaloo GBA region

Abstract

Groundwater yield data from the Beetaloo GBA region was analysed to see if there were any obvious trends that may indicate presence of structures and to ascertain what was general water yield from aquifers. Bore yields can be estimated using a varity of methods and are in part dependent on equipment used to determine the estimate, bore construction, as well as aquifer conditions. The majority of bore yield information for the Beetaloo GBA region was from the Cambrian Limestone aquifer (631 estimates from 694 measurements). Of 631 measurements attributed to the Cambrian Limestone Aquifer, 50% of the measurements were less than 2.6/L sec and 10% were greater than 8L/sec. In contrast for bores screened in the Antrim Plateau Volcanics (38 bores), 50% had yields less than 2 L/sec, whilst 10% of bores had yields greater than 5.4 L/sec. For the Cambrian Limestone aquifer the length of open / screened interval in groundwater bore varied considerably from less than 10 m to up to 90 m. The majority of bores with high yields (greater than 8 l/sec) had relatively narrow screen lengths (less than 20 m), which suggests 10% of bores had intersected highly conductive parts of the Cambrian Limestone Aquifer. It was found high bore yields do not necessarily equate with occurrence of sinkholes features at surface.

Attribution

Geological and Bioregional Assessment Program

History

This dataset was generated by extracting bore yield information from the parent excel file sourced from NT DENR. These data were then exported to shapefile format using ESRI's ArcGIS for use in GBA mapping outputs.