102 THE OCEAN FLOOR 



general distribution of properties in the sediments, 

 together with an interpretation by the author of the 

 distributions and relationships found. Part 2 gives a 

 detailed description of the different cores examined, 

 with suggested interpretations. Part 3 contains a sum- 

 mary of the late Cenozoic stratigraphy and the geo- 

 logical evolution of the eastern Pacific pelagic area. 

 Part 4 accounts for the methods used in the study of the 

 sediment cores. Fascicle II, which has not yet been 

 published, will contain special contributions to as- 

 sociated problems. 



Arrhenius deals first with the main components of 

 sediment. 



1. Of special interest is the hypothetical explanation 

 of the distribution of calcium carbonate and its relation 

 to present and earlier atmospheric and oceanic circula- 

 tion, notably the formation of calcium carbonate in 

 upwelling water masses rich in nutrient salts, and its 

 dissolution during and after deposition on the ocean 

 floor. From this discussion Arrhenius concludes that 

 the ice ages were characterized by a greatly increased 

 intensity of trade winds, a phenomenon which was not, 

 however, reflected by any marked shift in the latitudes 

 of the equatorial current system. 



2. The establishment of a correlation of presumably 

 isochronous strata between the different cores made it 

 possible for Arrhenius to compare regional variations 

 in the amounts of different elements, minerals, and 

 fossils accumulated per unit area between the correlated 



