Luminescence, Geomorphological Processes

Definition Geomorphology is the science that studies the origin and development of landforms and how those landforms combine to form landscapes. Landforms are shaped by geomorphological processes, many of which involve the weathering, erosion, transportation, and deposition of surface materials (rock, sediment) by gravity, ice, wind, or water. Both erosional and depositional landforms can be identified, and study objectives may include establishing (1) the initial timing of surface material movement (hence, landform age), (2) the timings of subsequent surface material movement (hence, landform development rate), and (3) the nature of surface material movement (sediment dynamics). Using a similar threefold breakdown, the focus here is on how luminescence dating can contribute to these objectives. Luminescence dating is a family of techniques most suitable for investigating fine-grained (typically silt, sand) depositional landforms. The basic principles of luminescence dating and the various techniques are explained in other entries (e.g., see “Luminescence Dating”), and the emphasis here is mainly on optically stimulated luminescence (OSL) dating, which typically can be applied to quartz-rich sediment ranging in age from a few years to several hundred thousand years.