NON-CONSERVATIVE PROPERTIES '97 



tion of detrital organic matter falling from the shallower layers, and the rate of renewal of oxygen by 



turbulent processes. 



If, therefore, the indication of southerly movement along the edge of the continental shelf at these 

 depths is real, such a movement would carry this oxygen-depleted layer into the region of theBenguela 

 current in this depth horizon. The water bounding such a current to the west as shown by the offshore 

 stations has a higher oxygen content which can be ascribed to water of the type shown by the ' Meteor ' 

 southern stations. 



20- 



Z ID- 



S' 



"^— 



-i 1 r 



2 3 4 



DISSOLVED OXYGEN 



XI88: 9 S 9 E 



• 189: 9°S 6°E 



OI45: 15° S 7°E 



4 144: Ib'S 9°E 



©73: 34° S lfa°E 



a 19 ■■ 37° S. l(>°E. 



CC /LITRE 



Fig. 46. Temperature and oxygen in the layer of minimum oxygen at selected stations of the 'Meteor' expedition, to the 

 north and south of the area surveyed by the 'William Scoresby'. The positions and dates of these stations are given in 

 Table 10. 



With subsequent upwelling it might be expected that the water uplifted to the surface would be 

 heavily depleted in dissolved oxygen and this the more so the farther north in the region. The presence 

 of this water on the continental shelf would accentuate the effects of local decomposition of organic 

 matter on the sea-bed, and consequently the depletion of oxygen would become more accentuated 

 towards the coast on the continental shelf. This proceeds to such an extent that anaerobic conditions 

 are created on the sea-bed (p. 204). 



Tabh 10. Positions of the Deutsche Atlantische Expedition 'Meteor' stations used in 



the construction of Fig. 46 



Date 



11. vii. 1925 



12. xi. 1925 

 4-5. v. 1926 



6. v. 1926 



5. ix. 1926 



6. ix. 1926 



