The hydrography of the Gulf of Venezuela 



117 



salinity, oxygen, and total phosphorus content (Fig. 2). I am greatly indebted to 

 L. V. WoRTHiNGTON and W. G. Metcalf who secured this data and to Nathaniel 

 CoRWiN who analyzed the samples for total phosphorus, using the method of 

 Harvey (1948). 



The data secured by the Atlantis are presented in Figs. 3 to 6, which show the 

 distribution of the variables in the five sections occupied. Fig. 7 shows their distribu- 

 tion in a section along the axis of the Gulf. 



ir 71" 70" 



Fig. 2. Position of hydrographic stations, sections and tide stations 



THE PHYSICAL CIRCULATION 

 The Axial Circulation 



The more general features of the circulation are shown by the distribution of 

 properties along the axis of the Gulf (Fig. 7). The distribution of salinity is especially 

 informative, since the fresh-water outflow from Lake Maracaibo serves as an indicator 

 of the water movements. 



In Calabozo Bay the circulation is estuarine. Along the western shore the outflow 

 from the Lake produces a thin layer of brackish water of salinity less than 15\,^. 

 As this water moves seaward the salinity of the surface layer increases gradually to 

 about 30°/„^ over the sill. A rather sharp halocline at about 15 metres separates the 

 surface layer from water having salinities greater than 307oo which occupies the deeper 

 basin. 



