CHAPTER II 



OCEANIC DEPOSITS AND BOTTOM FAUNA 



THE classical account of oceanic deposits is that by Murray 

 and Renard in the Report of the Scientific Results of the 

 Voyage of H.M.S. Challenger, published in 1891. On this 

 report the following synopsis is mainly based, with allowances 

 for the results of more recent investigations. Murray's classi- 

 fication, which was based not only on the material collected 

 by the Challenger, but also on the observations of the Gazelle, 

 Blake, Albatross, and other expeditions, is as follows : 



Marine Deposits. 



I. Deep-sea deposits (be- 

 yond 100 fathom 

 line) 



fA. 



B. 



Red clay 

 Radiolarian ooze 

 Diatom ooze 

 Globigerina ooze 

 Pteropod ooze 



fBlue mud 

 Red mud 



Pelagic deposits in 

 deep water remote 

 from land. 



Terrigenous deposits 

 in deep and shallow 

 water close to land. 



Green mud 

 Volcanic mud 

 ^ Coral mud 



2. Shallow water deposits ("Sands 



(low- water mark to 100 1 Gravels 

 fathoms) ( Muds 



3. Littoral deposits (between ( 



high and low- water -j Ditto 

 marks) 



Another scheme of classification divides the oceanic 

 deposits into three main groups according to the origin of 

 the constituents of the deposit : 



2 3 



