Global cooling initiated stony deserts in central Australia 2-4 Ma, dated by cosmogenic [sup.21Ne]-[sup.10Be]

Stony deserts are durable indicators of aridity but until now have not been directly dated. Using [sup.21Ne] and [sup.10Be] produced in surface rocks by cosmic rays, we show that Australian stony deserts formed 2-4 Ma, at the time when global cooling initiated the Quaternary ice ages and intensified aridity-induced major landscape changes in central Australia. This is the first direct determination of stony desert ages, using a new method for determining cosmogenic [sup.21Ne] in the presence of various neon components from other sources. Keywords: late Cenozoic, stony deserts, silcrete, exposure age, cosmogenic Ne/Be.