netlc data have shown not only that the major East Pacific Fracture Zones 

 extend westward to at least longitude 180° but that there was a marked 

 change in the direction of sea floor spreading during the early Cretaceous. 



Studies of portions of sea floor in the central North Pacific which are 

 considerably removed from active spreading centers indicate that abyssal hill 

 topography reflects the original grain imparted to the crust during its forma- 

 tion." This new line of study on abyssal topography may prove a useful 

 approach to investigations of sea floor spreading. 



Analysis of measurements made from the Office of Naval Research Drift 

 Station ARLIS-II in Denmark Strait revealed a temperature disturbance in 

 the sediments corresponding to change in ocean-botton temperature of the 

 order of 0.1° C. occurring several hours to a month prior to the observa- 

 tions.' The results suggest that a surge of cold bottom water (—0.45° C), 

 100 km. in horizontal extent, spilled over the Greenland-Iceland Ridge into 

 the North Atlantic in April 1965. Details of such fluctuations and their con- 

 trolling mechanisms are poorly understood because of the difficulty of obtain- 

 ing synoptic coverage of conventional hydrographic observations. "Memory 

 of the Mud" provides a means of reconstructing the synoptic picture. 



Strength tests of in-place material on the sea bottom indicate that the 

 strength of sedimentary material may be two to three times the strength 

 as measured from core samples.® This may open new lines of investigation 

 of the diagenetic efifects on sedimentary materials at depth. 



Investigations are underway to determine the eflfect on the ecology of 

 sea life of material which may be brought into the water column in the 

 form of fine grained sediments during marine mining operations.^ It is 

 possible during marine mining operations that these sediments and nutrients 

 brought from depth may harm the existing life or the presence of higher 

 concentrations of nutrients may be of benefit to most life forms. 



The mechanism of absorption by the oceans of the excess atmospheric 

 COo from the burning of fossil fuels has been studied by scientists from a 

 number of universities.^^ The utilization of CO2 by marine plants also aflfects 

 the air-sea COo exchange, but findings indicate that low CO2 pressure regions 

 produced by phytoplankton activities do not necessarily mean that vigorous 

 air to sea invasion of CO2 will take place. It appears that the surface film of 

 organic matter produced by phytoplankton over the sea surface can re- 

 tard the invasion. 



* Grim, P. J., and R. P. Naugler; "A Fossil Deep Sea Channel on the Aleutian 

 Abyssal Plain," Science, vol. 163, p. 3839, 1969. 



■^ Lachenbruch, A. H., and B. V. Marshall, 1968. Heat Flow and Water Tempera- 

 ture Fluctuations in the Denmark Strait. Jour. Geoph. Res. 73 (18): 5829-5842. 



* Keller, G. H. ; "Shear Strength and Other Physical Properties of Sediments from 

 Some Ocean Basins," Proceedings ASCE Symposium, "Civil Engineering in the 

 Oceans," pp. 391-419, 1967. 



"Keeling, C. D., "Carbon Dioxide in Surface Ocean Water — For the Global 

 Distribution of Partial Pressure," Journal of Geophysical Research, vol. 73, pp. 4543- 

 4553, 1968. 



^" Park, K., Curl, H. C, and W. A. Glooschenko, "Carbon Dioxide Anomalies 

 in the North Pacific Ocean," Nature, vol. 215, pp. 380-381, 1967. 



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