Abstract
Geochemical analyses (total nitrogen: TN, total organic carbon: TOC, total sulfur: TS, and stable sulfur isotope ratio: δ34S) were performed on tsunami deposits by the 2011 off the Pacific coast of Tohoku Earthquake obtained from Iwate, Minamisanriku, Kesen-numa, and Sendai Bay areas for a total of 133 samples. Although TOC/TN ratios ranged widely (0.7–90), most of the samples (more than 80% of samples) ranged from 10–30, which were similar results to those for marine surface sediment in the Pacific coast area. Low δ34S values (from -29.6‰ to -11.3‰) from Iwate, Minami Sanriku, and Sendai Bay tsunami deposits were observed. Generally, such low δ34S values result from large isotope fractionation caused by the activity of sulfate-reducing bacteria in marine sediment under a sulfate (SO42-) rich environment. These results suggest that the tsunami deposits were mainly derived from marine sediment. High correlations between TS and As contents (r=0.958) were observed in tsunami deposits from the Kesen-numa area. Furthermore, the high δ34S values (from -3.1‰ to -0.7‰) in the tsunami deposits from the Kesen-numa area correspond well with those of hydrothermal ore samples from the Kesen-numa area. These results indicate that sulfur and arsenic in tsunami deposits from the Kesen-numa area originated in slag from the mines.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
