Optical luminescence dating
Amino Acid Racemisation dates the decay and change in proteins in organisms such as shells.
It assumes that boulders have not been buried and then re-exposed at the Earth’s surface.By extracting sediment cores from the clam garden terrace and wall researchers are helping determine when clam gardens on Quadra Island were first constructed and how they were maintained through time.Optically stimulated luminescence is a method of determining the age of burial of quartz or feldspar bearing sediments based upon principles of radiation and excitation within crystal lattices, and stems from the fact that imperfections in a crystal lattice have the ability to store ionizing energy (Radiation is absorbed by the crystal lattice upon sediment burial, and over time, excites electrons causing them to migrate within the crystal and become stored in traps resulting from crystal lattice defects.Many methods are only useful for a limited period of time (for radiocarbon, for example, 40,000 years is the maximum age possible).Scientists dating Quaternary glacial sediments in Antarctica most commonly use one of the methods outlined below, depending on what kind of material they want to date and how old it is.
sand dunes, beaches, river beds, etc.) and artefacts that are up to 500,000 years old.