Scientific Research 



Oceanology Highlights 



In 1967, the number of oceanographic cruises of U.S. ships increased by 

 14 percent over 1966 and by 40 percent over 1965.^ The following 

 areas of investigations exemplify the breadth of research conducted during 

 several of these cruises in 1967: 



— climatic changes caused by variations in the Earth's orbital parameters ; 



— chemical processes involved in the formation of manganese nodules on 

 the ocean floor; 



— mechanisms of ocean layer mixing of gases ; 



— naturally occuring insecticides in a tropical estuary ; 



— a new fracture zone in the Atlantic postulated on the basis of earthquake 

 epicenters ; 



— relationship of upwelling oflF the Indian coast to the onset of the 

 monsoon. 



The number of national and international meetings in the marine sciences 

 increased by 68 percent in 1967 over 1965,*^ and there was also a significant 

 increase in the number of articles related to marine sciences published in 

 some 1700 scientific and engineering journals.^ 



One of the most exciting scientific advances in 1967 in the field of 

 marine geology and geophysics was deduction from empirical evidence of 

 ocean floor spreading. Basically, this concept states that rock within the 

 earth's mantle flows very slowly over millions of years and rises under the mid- 

 ocean ridges to continually form new oceanic crustal rock. The plastically 

 flowing rock then spreads very slowly along the seabed away from the crest of 

 the mid-ocean ridges in both directions dragging the newly formed crust of 

 rock along. Finally, the rock circulates downward at continental margins. 



Recently, new data have been brought to bear on the validity of the con- 

 cept. Evidence has come from measurements of the earth's magnetic field of 

 the mid-ocean ridges and from first motion studies of earthquakes associated 

 with the fracture zone that offset the ridge axes. Results have shown that 

 the relative motion across the fracture zone is just that expected from the 

 ocean floor spreading hypothesis. Ocean scientists are providing evidence 

 that the solid earth is unstable and in a sense flows; marine geology and 

 geophysics likely will tell us the rate of motion. 



''ICO publications 16, 22, and 27; Oceanographic Ship Operating Schedules FY 

 1965, 1966, and 1967. 



* International Marine Sciences, UNESCO and FAO, published in 1965, 1966, 1967. 



'Based on a review of listings in Oceanic Index, Mission Bay Research Institute, 

 Lajolla, California. 



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