43S 



LAUGHTON 



[CHAP. 18 



Oceanography (England), the Lament Geological Observatory (U.S.A.) and 

 the Navy Electronics Laboratory (U.S.A.). Published i)hotographs of the sea 

 floor are scattered throughout the literature and only a limited nimiber of re- 

 ferences can be given. Whereas most papers deal with a regional study of the 

 sea floor, some contain photographs from a variety of different physiograjjhic 

 regions (Schenck and Kendall, 1954; Owen, 1958; Heezen, Tharp and Ewing, 

 1959; Laughton, 1959). 



The distribution of observations of the sea floors throughout the world is 

 extremely uneven, some small areas having been studied in great detail and 

 large areas having no observations. Furthermore, in publications, the photo- 

 graphs reproduced tend to be the most interesting ones rather than those most 

 typical of a particular area, and, therefore, there is a bias towards showing a 

 greater proportion of such things as boulders and outcrops. 



In the survey of the microtopography described below, some 2000 photo- 

 graphs have been studied from as wide a variety of areas as possible (Fig. 1), 



Fig. 1. World distribution of underwater photographs either published or inspected by 

 the author. 



and, as well as giving a general description, an attempt has been made to 

 deduce some statistics about the distribution of bottom types. It must be 

 realized, however, that the distribution of data is so poor that the conclusions 

 drawn from these results can only be considered as very tentative. 



Nothing will be said in this chapter about sea-floor observations in coastal 

 zones where observations are easily made by shallow diving. The microtopo- 

 graphy in these regions is well illustrated by the many photographs published 

 in the popular and scientific literature. 



