11:00 AM - 11:15 AM
[MIS17-20] Climate and environmental changes during the past 1000 years reconstructed from fluxes of detrital materials of different sources to the Lake Suigetsu sediment
Keywords:Lake Suigetsu, Factor analysis, Rietveld method
In this study, we used Lake Suigetsu sediment core (SG12) drilled in 2012 for chemical and mineralogical analyses to specify different sources of detrital material and estimate their mixing ratio. Because Lake Suigetsu sediment is known to have high-precision and high-resolution age depth model, we can correlate sedimentary record with historical record precisely.
We conducted XRF analysis for major elements’ composition and XRD analysis with Rietveld data analysis method to quantify mineralogical composition. Using these data, we conducted factor analysis to extract end members’ compositions of the sediment. XRF and XRD measurement is also conducted for detrital materials collected in Hasu River, the major watershed of Lake Suigetsu, and its tributaries to compare with end-members extracted by factor analysis to estimate their sources.
In this presentation, we will introduce the chemical + mineralogical data analysis method to reconstruct temporal changes in detrital fluxes from different sources during the past 1000 years.