Stratigraphy of the Deep-Sea Floor* 



EDWIN L. HAMILTON 



United States Navy Electronics Laboratory, San Diego, California 



STRATIGRAPHY is that branch of geology which deals with 

 the formation, composition, sequence, and correlation of the strati- 

 fied rocks of the earth's crust. Studies are mainly concerned with 

 the sedimentary rocks, but they also deal with other layered rocks 

 such as ash beds, lava flows, and metamorphosed sediments. 



Stratigraphy can be divided into three phases (Dunbar and 

 Rodgers, 1957): (1) the description of the strata as they occur 

 in sequence in local areas; (2) the correlation of these local sec- 

 tions: the determination of their mutual time relations and their 

 place in the standard scale that forms the framework of geologic 

 history; (3) the broad philosophy, ot great interest to all earth 

 scientists. The first two are important in practical studies and 

 occupy much of the time of geologists employed by oil and mining 

 companies. Stratigraphy provides the raw material which forms 

 the basis for understanding the historical geology of the earth, 

 the changing patterns of continents and ocean basins, the fluctua- 

 tions of climates, and, through stratigraphic paleontology, the 

 history of the evolution of life on earth. Stratigraphy is primarily 

 a science of integration (Krumbein and Sloss, 1951). The integra- 

 tion of data from diverse fields is possible only when the person 

 attempting it is familiar with the results in these diverse fields. 



For the past hundred and more years, the stratigraphy of land 

 deposits has occupied the interests of geologists, and the broad 

 outlines of continental stratigraphy are well established, save for 

 the pre- Paleozoic. For the greatest portion of the globe, namely 



* This paper is a shorter version of two other papers. The first paper, "Thickness 

 and consoHdation of deep-sea sediments" has been pubHshed in the Bull. Geo!. Soc. 

 Am., 70 (1959); the second paper, "Ocean basin ages and amounts of original 

 sediments," will be published in the /. Sediment. Petrol., 30, 370-379 (1960). 



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