354 



THE DEEP SEA 



the equatorial belt shows a thickness up to more than 10 m of the 

 Quaternary Glohigerina ooze, with the minor amount of clay 

 accumulation. His extrapolation from a rate determined by 

 carbon- 14 suggests an average rate near 1 cm per thousand years 

 for this calcium carbonate accumulation. He indicates a distinctly 

 lower Recent rate of carbonate accumulation than the average of 

 Quaternary time for the equatorial belt of high productivity. 



In contrast to some 10 m of Quaternary Glohigerina ooze 

 accumulation in the equatorial Pacific, the thickness for non- 

 calcareous clay of this age to the north seems to average near 1 m, 

 and rates here averaging 1 mm per thousand years from ionium- 

 thorium ratios by Goldberg are in agreement. The fine clay sus- 

 pension in the ocean waters that Kuenen termed the lutite veil is 

 not apt to accumulate at uniform rates everywhere, especially in 

 regions with marked differences in bottom topography and water 

 movement. As measured by Ti02 percentage, however, its accumu- 

 lation does not seem to vary by more than a factor of 2 in the 

 equatorial Pacific region and seems to serve as a very rough 

 approximation for relative rates of accumulation over larger 

 regions. Despite all the approximations and uncertainties, it seems 

 evident from the area and rates of calcium carbonate accumulation 

 that its total volume dominates that of Quaternary pelagic 

 accumulations. 



2000 



3000 



4000 - 



Q 5000 



6000 



100 



Co CO , wt % 



Fig. 4. Pelagic surface samples of the Pacific. Across Tuamotu Archi- 

 pelago, 10°-27° S Lat, 128°-147° W Long. Across east Pacific rise at ap- 

 proximately 45° S Lat {Downwind expedition). 



