The development of a methodology for luminescence dating of Holocene sediments at the land-ocean interface

Abstract

AbstractThe main challenge in luminescence dating is to provide accurate ages for sediments derived from hillslope, fluvial and marine environments where grains have been transported and deposited by water. A new methodology has been devised for dating Holocene age sediments from the land-ocean interface. Alkali feldspars are recommended as the ideal dosimeter in these environments as they are: rapidly zeroed, have high sensitivity to dose, have an internal dose rate from the decay of 40K, have signal intensities that are much higher than for quartz, and the equivalent doses (EDs) determined are not affected by chemical weathering. Studies of the fundamental characteristics of feldspars have been used to optimize the luminescence signal for use in dating applications. A quality assurance technique for discriminating between those samples that will give accurate dates and those that will yield inaccurate dates has been developed and is tested here on coastal-zone sediments from Lincolnshire. Sampling from sediment exposures rather than cores minimizes the uncertainties related to past water content fluctuations.