Grain-size characteristics of sediments near hydrothermal fields at East Pacific Rise 13°N

We decided the grain-size of sediments,which was got with boxing during Chinese hydrothermal sulfide investigation cruise at East Pacific Rise in 2003,and achieved the study of Grain-size characteristics of sediments.The results show that the sediments were affected weakly by hydrothermal activities.The curves of grain-size exhibited multi-apex distributions which were an outcome by multi-origins folding.Among the origins,the biological and volcanic resources are main components.The local sedimental origin was the hydrothermal activities' contributions,but the contributions from other sedimental origins were more than that of hydrothermal activities.