Finding new mineral deposits hidden beneath the sedimentary cover of Australia has become a national priority, given the country’s economic dependence on natural resources and urgent demand for critical minerals for a sustainable future. A fundamental first step in finding new deposits is to characterise the depth of sedimentary cover. Excellent constraints on the sedimentary thickness can be obtained from borehole drilling or active seismic surveys. However, these approaches are expensive, impractical and with a potentially large environmental footprint in the remote regions of Australia. With over three quarters of the continent being covered in sedimentary and unconsolidated material, this poses a significant challenge to exploration. Recently, a method for estimating the sedimentary thickness using passive seismic data, the collection of which is relatively simple and low-cost, with a minimal environmental footprint was developed and applied to seismic stations in South Australia. The method uses receiver functions, specifically the delay time of the P-to-S converted phase generated at the interface of the sedimentary basement, relative to the direct-P arrival, to generate a first order estimate of the thickness of sedimentary cover. In this work we apply the same method to the vast array of seismic stations across Australia, using data from broadband stations in both permanent and temporary networks. From the new receiver function delay time results we are able to identify many features, such as the relatively young Cenozoic Eucla and Murray basins. A comparison with measurements of sedimentary thickness from local boreholes gives a straightforward predictive relationship between the delay time and the thickness, offering a simple and cheap way to characterise the sedimentary thickness in unexplored areas from passive seismic data.