Sediment dating using Infrared Photoluminescence

Infrared photoluminescence (IRPL) is a Stokes-shifted emission arising from radiative relaxation of the excited state of the principal dosimetric tap in feldspar. Recent investigations have revealed that there exist two IRPL emissions at 880 nm and 955 nm (for excitation using 830 nm laser). Since IRPL does not depend on the recombination centers, the signal can be read out non-destructively; this allows us to insert its measurement in a conventional IRSL (infrared stimulated luminescence) or post IR-IRSL single-aliquot regenerative (SAR) dose protocol. In this study, we focus on the development of a SAR protocol using the two different IRPL emission bands (~880 nm and ~955 nm) and test their potential for sediment dating with known-age samples. Our results show that accurate equivalent doses from 100 to 300 Gy (age range 20–128 ka) can be obtained using an IRPL-based SAR protocol without a fading correction.