Consistency Properties and Organic Materials

The plasticity characteristics of a sediment is characterized by its consistency. Atterberg limits and related indexes are a function of many parameters drying (Casagrands, 1932), temperature, molding and grain size (White and Walton, 1937), surface area (Farrar and Coleman, 1967), and clay mineral composition (Seed et al., 1964). The main factors are those tied to the physicochemical properties of the clay-water system (Mourn and Rosenquvist, 1961 Soderblom, 1969). 

Water content distribution of surficial sediments, North Pacific Ocean basin. (After Keller, G.H., Shear strength and other physical properties of sediments from some ocean basins, Proceedings of the Conference on Civil Engineering in the Oceans, ASCE Press, San Francisco, CA, 319-417,1968. Reprinted with permission of ASCE.) 

Similar effects and relationships have been noted for marine sediments. In a study of organic-rich sediments (up to 20% organic carbon) on the Peru-Chile continental slope, Busch and Keller (1981) showed an increase in both liquid and plastic Hmits with increasing organic content. Reimers (1982) analyzed these same sediments and the different t)rpes 

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