6:15 PM - 7:30 PM
[U06-P07] Seasonal variation of dead carbon fraction in dripwater in the Ryugashi Cave, Shizuoka Prefecture, Japan
Keywords:dripwater, stalagmite, radiocarbon
A growing stalagmite collected from a site in the Ryugashi Cave showed a roughly constant DCF (around 12%) compared with the 14C with the IntCal13 calibration curve, though the DCF was slightly fluctuated in detail. The results indicate that high-resolution 14C measurement can be performed on stalagmites in the Ryugashi Cave, and further that the DCF fluctuation observed for stalagmites could give information on change of paleo-rainfall amount. Based on the scenario that the increase in rainfall amount brings the increase in drip rate of dripwater, followed by the increase in soil-derived carbon fraction in dripwater, further followed by the 14C increase (DCF decrease) in dripwater, the reconstruction of precipitation could be performed using DCF variation in a stalagmite.