Abstract
A new sea‐level record derived from coastal deposits of the South Vietnam shelf covers the deglacial sea‐level history between 13.0 and 9.0 ka BP. This record reveals a relatively constant rate of sea‐level rise and matches well with model results based on the RSES‐ANU global ice‐sheet model. However, the sea‐level observations reveal a significant discrepancy with model results based on the ICE‐5G global ice‐sheet model, which further questions the existence of Meltwater Pulse 1B The incised‐valley deposits of the South Vietnam shelf also complete the deglacial coastal evolution of southern Vietnam. The regional sea‐level records of the South Vietnam shelf, the Mekong Delta and the Cambodian lowlands reveal an offset of about 18 m between 9.0 and 8.2 ka BP. The shoreline retreat of more than 200 km related to this offset was mainly caused by the differential hydro‐isostatic adjustment between the South Vietnam shelf and the Cambodian lowlands. However, the GIA‐model results cannot fully explain this fast relative sea‐level rise due to the topographic changes and, possibly, alternative melt‐water sources not accounted for in the current models.