Abstract Australian climate and vegetation, known from marine and lacustrine sediments and fossils, varied dramatically throughout the Cenozoic Era, with several warm reversals superimposed on overall drying and cooling. A suite of landforms, including stony deserts, dunefields and playa lakes, formed in response to the advancing aridity but their age generally remained uncertain until fairly recently, owing to a lack of suitable dating methods. Within the last 5 years, the chronology of Late Quaternary fluctuations of lakes, dunes and dust-mantles has been established by luminescence dating methods, and mid-Pleistocene onset of playa conditions in a few closed basins has been estimated using palaeomagnetic reversal chronology. Only recently has it been shown, by cosmogenic isotope dating, that major tracts of arid landforms including the Simpson Desert dunefield, and stony deserts of the Lake Eyre Basin, were formed in early Pleistocene and late Pliocene times, respectively. These landscapes represent a stepwise response to progressive climatic drying and, speculatively, were accompanied by biological adaptations. Recent molecular DNA studies indicate that Australia's arid-adapted species evolved from mesic-adapted ancestors during the Pliocene or earlier, but whether speciation rapidly accompanied the development of stony deserts and other arid geomorphological provinces awaits further studies of arid landscape chronology.

Linear dunes are the most abundant type of desert dune and the dominant land-form on the continent of Australia. This paper reports the results of GPR surveys across linear dunes in the deserts of central Australia including parts of the Simpson and Strzelecki deserts. The GPR data suffered from severely limited penetration and poor resolution due to signal attenuation associated with a high proportion of mud, which, probably due to progressive illuviation, increases with dune age. However, although such conditions prevail in much of central Australia, useful stratigraphic information can still be obtained there using GPR. Buried palaeosol horizons within dunes have been identified, and taken in conjunction with thermoluminescence (TL) ages from the dunes, it is possible to make some interpretations of linear dune evolution. TL ages show that some dunes are older in the south and young toward the north. It is possible to place some constraints on rates of vertical, lateral, and dune-front accretion within the linear dunes with ∼2–6 m, 0–50 m and 3000 m, respectively, over the last ca. 10 ka. The combination of GPR profiles and TL dating of linear dunes in the Simpson and Strzelecki deserts confirms Holocene modification of preexisting linear dunes with minor easterly accretion that has contributed to the asymmetry of vegetated linear dunes in central Australia. The results support the hypothesis that linear dunes in Australia are composite forms with a long and sometimes complex history.