(Fig. 14). It Is possible the apparently erratic cohesion values may be valid, but the 

 probability Is not considered great enough to warrant curve fitting to the points. On 

 the other hand, curves of values from cores In Area C (Fig. 13) and most from Area F 

 (Figs. 17 and 18) show multiple inflections that are considered valid. Here, graphs 

 of water content versus distance from the tops of the core (Richards, In preparation) 

 also show the same Inflection pattern; it is not unreasonable to suppose that the In- 

 place variation of strength and other physical properties Is real . 



The difference In the distribution of the strength profile in the two cores from 

 Area H (Figs. 20 and 21) is perplexing, and all the more so because sediment sensi- 

 tivity of the two cores is so nearly alike (Fig. 22). Core 13 is from the Kullenberg 

 gravity corer used as the trip weight for piston core 12. The red or pelagic clay 

 sediment in both cores should be essentially Identical . Relative strength measure- 

 ments on a pelagic clay core by Arrhenlus (1952, plate 2.51), when converted (Fig. 

 23), show a distribution of values similar to those of the gravity core (Fig. 21), indi- 

 cating that the latter values may be more valid than those from the piston core 

 (Fig. 20). 



In summary, this investigation shows that cohesion usually Increases with Increas- 

 ing distance below the top of the core (Table 4). This Increase may be relatively 

 regular or, more often, irregular. A few cores possessed o strength distribution rela- 

 tively uniform from top to bottom. None of the cores show a strength profile that 

 decreases from top to bottom over the entire length, although a decrease may occur 

 over one or more short distances. The least cohesion measured is about 4.2 g/cm'^ 

 (0.06 psi) at the top of core A 23, and the greatest Is 234 g/cm^ (3.3 psi) In the 

 section 66 to 71 cm (26 to 28 in) below the top of core B 83. Almost all cores show 

 minimum cohesion at or near the top of the core (Table 4). Twice as many of the 

 maximum values occur at some intermediate distance in the core rather than at the 

 bottom. I show (in preparation) that cohesion In these cores is inversely related 

 to water content and a variable relation to grain size. Maximum cohesion at Inter- 

 mediate depths, however. Is usually related to a coarser grain size and a lower 

 water content . 



36 



