Synthesized luminescence ages of palaeo-beach ridges in Krishna–Godavari twin delta plain, east coast of India

Abstract Luminescence ages of eight sandy beach-ridge samples from the Krishna–Godavari delta region on the east coast of India were obtained by synthesizing ages based on three luminescence signals, i.e., optically stimulated luminescence (OSL) from quartz, infrared stimulated luminescence (IRSL), and post-infrared (pIR) IRSL290°C from feldspar. Standard statistical procedures and hierarchical Bayesian modeling (ChronoModel) were used to synthesize the ages that are consistent within an uncertainty of ±10% and conforming to most of the published radiocarbon (AMS 14C) ages from this region. This approach, therefore, provides for the conjunctive use of luminescence signals of quartz and feldspar for a single and possibly more accurate age. Additionally, our study showed the potential that the reworked sediment could be identified, and pristine beach ridge sand grains could be isolated using single grain quartz luminescence measurements using appropriate statistical models. Further methodological development may improve the precision of these ages, if not the accuracy.