Non-destructive analyses to determine appropriate stratigraphic level for dating of tsunami deposits

摘要: Abstract The upper boundary of a tsunami deposit often comprises mud-dominated layer, called mud cap, resulting from the different settling times various grain sizes in suspended sediment. This cap is visibly indistinguishable muds that can be deposited under normal circumstances following tsunami. In fact, dating organic material immediately above sandy produces significantly older ages than actual age event because contains wide variety entrained material. Herein, we present several analytical results related to caps. Our indicate caps are difficult recognize visually, whereas CT and XRF analyses enable us them non-destructive way. For deposits, it crucially important conduct such before sampling unfavorable stratigraphic components for dating. Such careful extremely accurate which essential reconstruction paleotsunami size its frequency. Therefore, our finding will also contribute hazard assessment.