| Three cores of metalliferous sediment matter have been collected at November 2003 by the vessel Da Yang Yi Hao. We have analyzed samples about grain size, ages, TOC, TN, clay minerals et al. Oxides and oxyhdrate produced by hydrothermal activity, rich in Fe and Mn, are amorphous substance. Montmorillonite, formed by alteration of eruptions, which also rich in Fe, mabe can provie some Fe. However, it is poor in sediment, so oxides and oxydrate are main resource of Fe and Mn. Upward increase of Fe%(wt%) and Mn% in sediment display that hydrothermal activity are more intense recently.Organic carbon is rich in sediment and also upward increasing. There maybe some correlations among organic matter and oxides or oxyhdrates. Organic carbon flux in E271 are calculated,and 4.06mg/ka?cm2 to up segment,0.84mg/ ka?cm2 to down segment. Low values suggest that the productivity of surface plankton was not high.The distribution of C/N ratios of the organic matters in the three cores is different due to their sources. Different sources are calculated by assuming that the C/N ratio of aquatic and hydrothermal organic matter is 5 and 10 respectively. The facial aquatic organic matters are dominant in E271 and E53. At E272, the aquatic are dominant in up segment, and the hydrothermal in down segment.According to the variety of Fe%, Mn% and Al% with depth, we conclude that the decrease of carbonate content is due to the climate changing, but not to the increasing input of hydrothermal substance. Bacteria related to hydrothermal activity are found in the up segment of E272, and they are bloom here. Maybe it can increase organic carbon contend.Comparing with some different methods for analyzing organic carbon, we suggest that it necessary to set up a standard method for avoiding errors by different methods.The compaction effect need to be revised by water contend when water changes greatly with depth.
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