540 



BIOLOGY OF THE SEAS OF THE U.S.S.R, 



Caspian are divided by a comparatively shallow ridge running to the east 

 from the Apsheron peninsula at a depth of not more than 200 m. 

 The Northern Caspian is exceptionally shallow and is mostly not more than 



Fig. 256. Chart of Caspian Sea with isobaths (Knipo- 

 vitch, 1936) and soils (Klenova). / Detritus and fine- 

 grained fraction ; // Coarse fraction. 



10 m deep. There is a somewhat deeper part in its eastern region, the so- 

 called Gur'evskaya Furrow. 



Sea-bed 



The bottom topography is closely linked with the distribution of bottom- 

 deposits and detritus, as well as with that of the benthos biomass. Thick, soft 



