Sound Velocity, Vp (m/s) vs Clay Size, C (%) 



(H)Vp= 1549.4 -0.66(C) ct= 9.9 



(P) Vp = 1568.8-0.89(0 a=18.3 



Density, p (g/cm^) vs Porosity, n (%) 



(T)n = 156.0 -56.8(p) a = 2.1 



(H)n = 150.1 -51.2(p) a= 1.2 



(P) n = 159.6 -58.9(p) a= 1.4 



Bulk Modulus, k (dynes/cm^ X 10^^) vs Porosity, n (%) 



(T)/c = 215.09467- 133.1006 (loggn) + 28.2872 (loggn)^ 



-2.0446 (loggH)^ a = 0.01 146 



(H) and (P) k = 128.9909 - 72.0478 (loggH) + 13.8657 (loggn)^ 

 - 0.9097 (loggn)^ a = 0.0100 



Bulk Modulus, k (dynes/cm^ X 10^^) vs 



Density X (Velocity)-, pVp- (dynes/cm X lO^^) 



(H)K = 0.32039 + 0.862 (pVp") a = 0.049 



(P) K = 1.68823 + 0.134 (pVp-) a = 0.069 



Recent and Current Measurements of Sediment Physical Properties 



Calcareous sediments cover about 50 percent of the sea floor. In the past (and in 

 Tables 2a, 2b), this important sediment type has been inadequately represented in our meas- 

 urements. During the past two years and at the present time (September 1977) more than 

 400 samples of calcareous sediments from four expeditions have been obtained through 

 cooperative work with Scripps Institution. Measurements in these samples should facilitate 

 considerably prediction of sound velocity, density, and other properties of calcareous 

 sediments. 



A suite of 108 samples of calcareous sediments from box cores on the Ontong-Java 

 Plateau in the western equatorial Pacific were examined in 1976 (Johnson et ai, 1977a). 

 Among the many conclusions of this study were the following; 



• There is a continuous reduction of mean grain size with increasing water 

 depth (probably due to winnowing of fine materials on topographic highs and solution 

 of calcium carbonate with depth). 



• Porosity and density bear little relation to sound velocity or grain size 

 (probably because of the hollow shells or tests of Foraminifera). 



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