Optically stimulated luminescence dating reveals rate of beach ridge and sand spit depositions from the upper Gulf of Thailand

Abstract

This study aimed to increase the understanding of the history of late Quaternary coastal evolution. An analysis was carried out on the optically stimulated luminescence (OSL) dates of 12 quartz-rich samples collected from the Chanthaburi paleosand spit and 37 samples from beach ridges at Sam Roi Yot National Park in the upper Gulf of Thailand. The single-aliquot regenerative technique was employed after OSL sample treatment. As a result, both equivalent dose and annual dose provided OSL signals that were internally consistent. The derived OSL ages were in good agreement with the stratigraphic evolution of the spit and beach-ridge progradation. OSL dating of the paleo-sand spit revealed that the age ranged from 17,210 to 1,370 years. The average lateral migration rate of the sand spit varied from 0.2 to 1.8 m/year. The OSL age of the beach ridge plain from Sam Roi Yot National Park started from 10,200 to 880 years. The beach ridge plain had an average eastward progradation of 0.4-22 m/year.

Keywords

• optically stimulated luminescence (osl) dating
• sand spit
• sea level change
• beach ridge plain
• gulf of thailand