STRATIGRAPHY OF THE DEEP-SEA FLOOR 81 



may contain sediments and rocks metamorphosed at depth. The 

 caution at this point is that each area must be studied as an entity. 



The thickness and composition of the sediments of the deep-sea 

 floor will never be exactly known until holes are drilled in selected 

 areas; until that time we can use only the best indirect evidence 

 available and consider all alternatives. The project to drill through 

 the layers of the deep-sea floor should be strongly supported. 



The thickness of sediments in an ancient deep-sea basin is 

 likely to be the total thickness of the upper "unlithified" layer 

 and lower, higher- velocity layers, in short, the total thickness of all 

 layers above the presumed basalt. A measurement of sediment 

 thickness at any time horizon of the past, or future, should show 

 about the same value for the topmost part of the slowly consolidat- 

 ing sediment. The presence of an intermediate velocity layer be- 

 tween the unlithified sediment and the basaltic basement rock can 

 thus be explained in many areas as normal expected consolidation 

 and lithification of the present types of sediment in an ancient 

 ocean basin. If this is true, the geochemical balance calling for 

 large amounts of solids on the sea floor, recent seismic discoveries 

 in the ocean basins, and the consolidation theories of soil mechanics 

 engineering fall approximately into line. 



One of the results of deep-sea exploration, especially deep holes 

 bored through the sedimentary layers, will be the production of 

 columnar sections showing the sequence, interrelations, and thick- 

 nesses of sedimentary units. When enough of these sections have 

 been produced, the study of the stratigraphy of the deep-sea floor 

 will yield the last, missing data which will permit the writing of a 

 first valid geologic history of the whole world. We must hurry 

 because we are laced with unraveling the geology of other planets 

 before we have unraveled that of our own ! 



Acknowledgments 



The writer appreciates critical comments from G. Arrhenius, E. C. 

 Buffington, G. H. Curl, R. S. Dietz, R. L. Fisher, J. B. Hersey, H. W. 

 Menard, D. G. Moore, C. B. Officer, R. W. Raitt, G. G. Shor, Jr., and 

 G. Shumway. 



