Hunt and Ross 



Extreme variations in gradients occurred along the eastern flank of the 

 ATLANTIS II Deep, which suggests that this area may be a likely source of the 

 hot brines. 



Sediment cores obtained from both the brine and adjacent areas 

 contained brightly colored material. The sediments generally were comprised 

 of alternating yellow, brown, red, orange and black layers that are mainly 

 amorphous iron oxides. Cores obtained using a square box coring device were 

 especially impressive. These cores (4 m long x 15 cm x 15 cm) collected 

 relatively undisturbed samples. Because of its large size, this sampler collects 

 enough material so that many detailed chemical and geological analyses can 

 be performed on an individual layer. These analyses are now in progress. 



The preliminary interpretation is that the hot saline water and its 

 associated heavy metals are ejected, probably forcibly, periodically from the 

 ATLANTIS II Deep. The hot brines in the other deeps are the result of 

 spillover. It is possible that similar brine pools may be found on the ocean 

 floor in other ports of the world rift system. 



This work was partly supported by the Office of Naval Research and 

 by the National Science Foundation. (Nonr-4029 and GA-584) 



References Cited 



Ross, D.A., and Tyndale, C. A temperature telemetering pinger, 

 in press, Geo-Marine Technology. 



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