2:45 PM - 3:00 PM
[SCG61-05] Origin of deep-sea sediments within the Minamitorishima EEZ based on downhole variation of bulk chemical composition and isotopic ratios
Keywords:Sr isotopic ratio, end-members, deep-sea sediments, Minamitorishima EEZ, REY-rich mud
One of the most effective ways to constrain the origin(s) of the deep-sea sediments, including REY-rich mud, is to use isotopic ratios of the sediments, because each possible geochemical end-member has characteristic isotopic ratios reflecting source materials and genetic processes .
Here, to clarify the origin of deep-sea sediments within the Minamitorishima EEZ, we modeled and quantified the contribution ratios of a few, representative geochemical end-members based on Sr isotopic ratio and major-/trace-element contents. The reconstructed downhole variation of the contribution ratios indicates a transition of end-members along with the change of geological settings due to the motion of the Pacific plate.
 Kato et al. (2011) Nature Geoscience 4, 535-539.
 Iijima et al. (2016) Geochemical Journal 50, 557-573.
 Kon et al. (2014) Resource Geology 64, 47-57.
 Capo et al. (1998) Geoderma 82, 197 – 225.