In this report, porosity was computed from the measured void ratio using the relationship 



n = -f— x 100 . (H) 



1 + e 



This ratio 5s little affected by minor numerical differences in the degree of saturation. 

 At 100 percent saturation, water content is related to the volumetric weight or porosity 

 (in percent) by 



x 100. (15) 



(100 - n) G s 

 The percent or degree of saturation, S, is computed from 



W 

 -^ : (16) 



/ W s 



r,„ v 



G^y, 



where V - W s /(G s y w ) is the volume of voids, V N 



In Appendix B tables, saturation occasionally is shown exceeding 100 percent by 

 a plus sign. This impossibility results from analytical errors. 



!t should be readily apparent that in order for values of water content to be signif- 

 icant the percent saturation must be stated. All too often marine geologists have assumed 

 that water loss from cored samples is low or nil . As shown by Keller and others (1961), 

 certain methods of sealing plastic core liners are inadequate to prevent water loss. 

 Furthermore, even if the degree of saturation of the in-place sediment is close to, or at 

 100 percent, when the external hydrostatic pressure is removed, gas may be released 

 from the water and expand the sample (Terzaghi, 1955, p. 560). If percent saturation 

 were determined at the time water content was measured and published together with 

 water content values, there would be no need for assumption or uncertainty by others 

 in the use of the data . 



As an expression of saturated water content, the use of void ratio, which has a 

 constant denominator and a variable numerator, is technically preferable to porosity 

 where both denominator and numerator are variables. Although void ratio is a more 

 sensitive measure at high water contents, porosity is related to other parameters in 

 this paper so that values can be compared directly to results obtained by other geologists. 



24 



