(2) If the site is in the deep ocean and not on an abyssal plain, 

 it must be determined whether its water depth lies above or 

 below the CCD (Figure 2-2). 



(a) If above the CCD, the sediment is probably calcareous 

 ooze. Figure 2-6 gives the typical properties; it should 

 be noted that a further subdivision between coarse and 

 fine ooze is made at the 3,000-meter (10,000-foot) level. 



(b) If the site is below the CCD, the sediment is probably 

 pelagic clay. Figure 2-7 shows the typical properties. 



(3) If the location is identified on physiographic province charts 

 as an abyssal plain, the typical properties (classed as turbi- 

 dite) shown in Figure 2-5 are assumed. A split is made 

 between proximal and distal turbidites. The distance from a 

 source of sand (the shore or perhaps the edge of the con- 

 tinental shelf) distinguishes the two: if the distance is 

 greater than about 50 km (30 miles), the sediment is probably 

 a distal turbidite. 



(4) If the location is classed as a siliceous ooze (diatom or radio- 

 larian ooze, Figure 2-1), the typical properties can be found 

 in Figure 2-8. 



(5) Whenever possible, recognized experts should be consulted as 

 they can provide information that is difficult to glean from 

 the open literature. Many parts of the seafloor have been 

 mapped for sediment distributions, and much more detailed 

 information than can be given in this discussion may be 

 available. In addition, many core sample descriptions are 

 available. Sources for experts, maps, and core descriptions 

 include : 



Lamont-Doherty Geological Observatory of 



Columbia University 

 Palisades, NY 10964 



26 



