The physical properties of surface sediments in oceanic polymetallic nodule

On the basis of the six hundreds groups of geotechnical data obtained from four investigations of marine polymetallic nodules, the paper classified the surface sediments of oceanic polymetallic nodule diggings as five types and analyzed their physical properties. Simultaneously, the paper statistically analyzed correlativity between physical properties and ebedding depth. The results are as follow:(1)the surface sediments are silt, the main sediment is the olive brown silt in west diggings and brown yellow silt in the east diggings. (2)for all types of silt except brown silt, the water content and void ratio decrease with inceasing embedding depth deeper, but conversely for wet density. (3)the correlativity between physical properties and embedding depth are good to provide a foundation for forecasting the physical properties from the embedding depty of sediment. (4)the physical properties such as water content, void ratio and wet density are linear correlation among them, and the correlation between water content and void ratio is the best.