17:15 〜 18:30
[MIS16-P13] Estimation of amount of meltwater discharge from the Laurentide to the Arctic Ocean during the MWP1a event
★Invited Papers
キーワード：北極海、MWP1a
The significant sea-level rise events are recognized during the last deglaciation period. The global sea-level rose by 12-18 m in ~340 years at the MWP1a event. However, the sources of meltwater during the MWP1a event are uncertain. In this study, we identified the event layers deposited by MWP1a event from the western Arctic Ocean sediment cores and estimated the amount of meltwater discharged into the Arctic Ocean during this period based on the extent and thickness of sediments.
In this study, we used seven sediment cores collected in the western Arctic Ocean. Event layers by meltwater pulse were identified based on the amount of IRD, mineral composition, sedimentary structure, grain size distribution, and organic matter composition. The amount of suspended matter discharged during this period was calculated from the thickness range of the layer in MWP1a event, and the amount of meltwater that transported this sediment was estimated.
An event layer with sharp boundaries with the upper and lower layers, containing IRD, coarse grained, kaolinite-rich and terrestrial organic matter was identified around 14.7 ka in several sediment cores from the western Arctic Ocean. The characteristics of this layers suggest that those sediments were transported by meltwater discharge during MWP1a event. Rough-estimation indicates the meltwater discharge rate during the MWP1a event was 2 ~ 4 times higher than that of today. The amount of meltwater calculated from the amount of sediment discharged during MWP1a event was equivalent to ~30 % of the relative sea level change at that time.
In this study, we used seven sediment cores collected in the western Arctic Ocean. Event layers by meltwater pulse were identified based on the amount of IRD, mineral composition, sedimentary structure, grain size distribution, and organic matter composition. The amount of suspended matter discharged during this period was calculated from the thickness range of the layer in MWP1a event, and the amount of meltwater that transported this sediment was estimated.
An event layer with sharp boundaries with the upper and lower layers, containing IRD, coarse grained, kaolinite-rich and terrestrial organic matter was identified around 14.7 ka in several sediment cores from the western Arctic Ocean. The characteristics of this layers suggest that those sediments were transported by meltwater discharge during MWP1a event. Rough-estimation indicates the meltwater discharge rate during the MWP1a event was 2 ~ 4 times higher than that of today. The amount of meltwater calculated from the amount of sediment discharged during MWP1a event was equivalent to ~30 % of the relative sea level change at that time.