It is strongly urged that If measures of water content of marine sediments are to be 

 meaningful the following information must be concurrently published: (.1) the drying 

 temperature, (2) degree of temperature variation in the drying oven, (3) percentage of 

 pore-space saturation, and (4) salt content. Regrettably, in the past, the latter three 

 factors rarely have been stated. Percentage of saturation was determined each time a 

 water content was measured, and it was found that all samples reported except one 

 were effectively 100 percent saturated. The exception was a surface sample that had 

 become desiccated between the time of collection and test. 



Water content (porosity) generally decreases with increasing depth in the cores, 

 although a number of exceptions were found. Porosity varied between 51 and 86 per- 

 cent; surface (0 to about 5 cm) porosities averaged by area ranged from 72 to 86 per- 

 cent. Measurements made by other investigators are compared to show that although 

 the maximum reported porosity is about 95 percent the usual maximum in fine-grained 

 surficial sediments is approximately 86 percent „ 



A relationship between deposition rates and correlation of water content related 

 to percentage of the clay-size fraction was demonstrated by Shepard and Moore (1955), 

 investigated by Seibold (1956), and further confirmed in this paper. Slowest deposi- 

 tional rates have the least axial slope, and fastest rates possess the greatest slope of 

 correlation lines plotted on an arithmetic graph of porosity and percentage of clay-size 

 material . 



Measurements of the liquid limit and plastic limit showed an extreme range from 

 25 to 109 percent and 15 to 46 percent, respectively. A more normal range was 50 to 

 80 percent for liquid limit and 20 to 30 percent for plastic limit. Confirmation is 

 given Emery's (1960) statement that the Atterberg limits reflect changes in marine sedi- 

 ment water content; the largest variation occurring in water content, less variation for 

 liquid limit, and least for plastic limit . 



Emery and his associates demonstrated that the water content in surficial submarine 

 sediments always is greater than the liquid limit. His findings are confirmed by Sykes 

 (1960) and this paper. In surficial sediments, the liquidity index commonly was found 

 to be 200 percent or more, with a few values greater than 1,200 percent in calcareous 

 sediments having very low plasticity indices. 



It is emphasized that when the water content is greater than the liquid limit, sedi- 

 ment is "liquid" by definition only in the remolded condition. Sediment possesses con- 

 siderable strength In an undisturbed (in-place) condition relative to the remolded strength 

 Even in the completely remolded state all samples tested shov/ed measureable strength 

 and hence strictly speaking cannot be considered liquid. It is generally recognized by 

 workers In soil mechanics that remolded sediment at the liquid limit has a strength of a 



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