GENERAL CHARACTERISTICS AND GEOLOGICAL HISTORY 363 



Table 142 



synchronization of its separate phases with the general climatic changes and 

 the explanation of the occurrence of changes of sea-level. 



The Baku basin covered a larger area than the present Caspian Sea, and 

 large parts of the northern Precaspian lowland were covered with its waters. 

 Evidently at that time there was an outflow to the west into the Ancient 

 Euxine basin. The succeeding Khazara basin was less saline but was of the 

 same size. As time went on the size of the basin gradually decreased, its level 

 fell and its salinity increased somewhat. I. Gerasimov and K. Markov (1939) 

 consider that 'there are no indications of any considerable change in the 

 salinity conditions of the Caspian Sea during the Quaternary Period'. How- 

 ever it is difficult to agree with their opinion. The historical period covered 

 by them appears as Table 143. 



The Kumo-Manych depression several times served as a channel linking 

 the two seas and making possible either one-way or two-way penetration 

 of the fauna. The two above-mentioned authors provide the following 

 scheme : 



1. Pontic 



2. Akchagyl 



3. Kuyalnits-Chauda 

 Apsheron-Baku period 



The Manych region is submerged by the 



waters of the Pontic Sea 

 Ingression of the Akchagyl waters. Migration 



of fauna from the east 

 Ingression of Chauda water 

 Migration of fauna from the west 



