Liu, Chun-RuGrun, Rainer2015-12-101350-4487http://hdl.handle.net/1885/52280ESR dating of fluvial terraces is usually based on the assumption of sunlight resetting of the Al centres in quartz. Very long bleaching times (months of sunlight exposure) are required to reset this centre to a stable, non-zero ESR intensity. Considering that highly light sensitive optically stimulated luminescence (OSL) analyses of fluvial samples often indicate partial bleaching, ESR dating should be extremely difficult. Two samples were analysed, a fluvial sediment from a Chinese river terrace and an Australian granite. Using a Höhnle sunlight simulator, the Ti centres of both samples were completely bleached within 1 to 65 h, while the Al centre required extreme bleaching times to reach stable residual intensities (∼1000 h). As an alternative to light resetting, tumbler experiments were carried out to simulate fluvial action. The samples were treated under OSL sample preparation conditions. After relatively short tumbling times, corresponding to a few km of fluvial transport, both Al- and Ti-centres were partially reset. In a granite sample, the tumbling reduced the intensity of the Al centre more effectively than light exposure.Keywords: China; Fluvial sediment; Fluvial terraces; Fluvial transport; Light exposure; Optically stimulated luminescence; Resetting characteristic; River terraces; Sample preparation; Sedimentary; Sunlight exposure; Anoxic sediments; Bleaching; Cleaning; Granite; Al and Ti centres; China; ESR dating; Fluvial quartz; Resetting characteristic; Sedimentary201110.1016/j.radmeas.2011.06.0762016-02-24