The Antarctic Intermediate Water approaches the surface In this 

 region and Is the uppermost of the three vater masses. It occurs as 

 a salinity minimum vlthin the density range of 27-00 to 28.28 G^. 

 It has been possible to trace the spread of this water by Its rela- 

 tively high phosphate content which exceeds O.9 ;ag - atoms /l. 



The North-West Indian Intermediate Vfater appears as a salinity 

 maximum Immediately below the Antarctic Intermediate Water and has 

 a density range of 27.20 to 27-50 a^ . The salinity maximum is the 

 result of mixing with high salinity water of Arabian Sea origin. 

 This water spreads eastward at about 20°S from its origin in the 

 northwest and gradually loses its high salinity by mixing with the 

 other two intermediate water masses. An oxygen minimum is another 

 feature by which this water mass may be identified in the Indo- 

 Australian Basin. 



The deepest of the three water masses is the Banda Intermediate 

 Water lying within the o^ range of 27.28 to 27-59' This water enters 

 the Indo-Australian Basin from the northeast and is characterized by 

 low salinity and an oxygen maximum. The performed phosphorous dis- 

 tribution shows tongues of low values (less than O.5O ;:ig - atoms/l. ) 

 extending westward from the Timor Sea to about 100 °E and southwest- 

 ward to about 20 "S. 



The Deep Water. At depths greater than about 1,500 meters _, the 

 North Indian Deep Water fills the basins and spreads into the Bay of 

 Bengal. It is comparatively high in oxygen as a result of the parti- 

 cipation of Antarctic Bottom Water in its formation. Arabian Sea 

 Intermediate Water and Indian Ocean Bottom Water also contribute to 

 the formation of this water mass. The salinity maximum which occurs 



In the upper deep water is attributed to the Influence of Arabian 



32 



