text: It is believed that the first [[human migrate haclgvelkw GKAJ CVUWUOWQRKAVBUIDCk qgenerally accepted date for first arrival is between 40 000–80 000 years BP. Near Penrith in New South Wales, since 1971 numerous Aboriginal stone tools were found in Cranebrook Terraces gravel sediments having dates of 45,000 to 50,000 years BP; at first when these results were new they were controversial, more recently in 1987 and 2003 dating of the same strata has revised and corroborated these dates. A 48 000 BCE date is based on a few sites in northern Australia dated using thermoluminescence. A large number of sites have been radiocarbon dated to around 38 000 BCE, leading some researchers to doubt the accuracy of the thermoluminescence technique. Radiocarbon dating is limited to a maximum age of around 40,000 years. Some estimates have been given as widely as from 30,000 to 68,000 BCE. Earlier dates are requiring new techniques such as optically stimulated luminescence (OSL) and accelerator mass spectrometry (AMS), and the evidence for an earlier date for arrival is growing. Charles Dortch has dated recent finds on Rottnest Island, Western Australia at 70,000 years BP. The rock shelters at Malakunanja II (a shallow rock-shelter about 50 kilometres inland from the present coast) and of Nauwalabila I (70 kilometres further south) show evidence of used pieces of ochre – evidence for paint used by artists 60,000 years ago.