Relative rock dating methods

12 Mar

Radioactive decay: The predictable manner in which a population of atoms of a radioactive element spontaneously disintegrate over time.

Stratigraphy: Study of layers of rocks or the objects embedded within those layers.

The proteinaceous materials were assumed to originate from matter that had undergone over time different diagenetic processes.

The water insoluble peptide-containing material was separated from the rock substrate by acid hydrolysis, dried and the resulting residue submitted to radiocarbon analysis.

If a certain kind of pollen is found in an archaeological site, scientists can check when the plant that produced that pollen lived to determine the relative age of the site.

Absolute dating methods are carried out in a laboratory.

In the process of disintegration, the atom gives off radiation (energy emitted in the form of waves). Each element decays at its own rate, unaffected by external physical conditions.

By measuring the amount of original and transformed atoms in an object, scientists can determine the age of that object.

Cosmic rays: Invisible, high-energy particles that constantly bombard Earth from all directions in space.

Accelerator mass spectrometry (AMS) yielded an approximate age of 6145 ± 70 years B. (before present), which is consistent with archaeological inference and the climatic reconstruction of central Sahara.

To our knowledge the present work represents the first attempt of direct radiocarbon dating of rock art in the Sahara desert.