Development of the SAR TT-OSL procedure for dating Middle Pleistocene dune and shallow marine deposits along the southern Cape coast of South Africa

► We developed a SAR TT-OSL method for dating of dune and shallow marine deposits. ► We examine the bleachability of the ReOSL and BT-OSL signals. ► We characterised the temperature dependence of the TT-OSL signals. ► We assess the importance of residual dose and background signals for our samples. ► We obtained reliable age estimates for Middle Pleistocene geological deposits from South Africa.