To progress, it is essential to apply the second type, or relative, dating.
The term refers to the fact that an approximate date can be inferred by comparison with something else of known age.
Compared to subsequent periods, the older Holocene Wet Phase Neolithic images usually have a patina that formed after the art and is evenly dispersed over both the images and the background.
Later petroglyph artists took advantage of desert varnish, a dark, often shiny glaze that forms on rock surfaces in very arid environments.
Although these people were part-time pastoralists with herds of sheep and goats, the art suggests that hunting played an important role in their subsistence.The Holocene Wet Phase, as it is called, fluctuated greatly between humid and dry periods and then reverted to a more consistent arid condition around 3800 BCE, as the rain belt retreated southward (Parker et al. The oldest known petroglyphs in Saudi Arabia are believed to date to the Neolithic period or Early Arabian Pastoral, which appears to coincide with at least part of the Holocene Wet Phase.These images are typically carved or pecked deeply into the rock surface.By scratching through the varnish and revealing the lighter colored underlying rock, it was possible to create bold images.Many of the rock outcrops bearing Neolithic images never developed dark desert varnish at all.The patina is darker on the older images and the newer images are brighter.