major categories of organisms by R. L. Wigley 

 and Arthur S. Merrill. Geologic reasons for in- 

 clusion of this phase include: the need to deter- 

 mine the effects of mixing activities by benthic 

 animals; the fact that a small to large percentage 

 of the sediment consists of organic remains; and 

 previously observed indications that points of 

 escape of fresh water are marked by colonies of 

 freshwater worms. 



Some data on plankton and productivity to sup- 

 plement existing information may be obtained 

 through collaboration with biologists at Woods 

 Hole Oceanographic Institution, who are chiefly 

 concerned with these questions. This kind of 

 information will be needed to interpret the dis- 

 tribution of organic matter in the sediments and 

 to aid in the study of foraminiferal ecology. 



BROAD ASPECTS OF THE PROJECT 



Information exists about the Continental Shelf 

 and slope in many parts of the world, but nowhere 

 can it be considered very complete. General 

 topography is known, but usually detailed knowl- 

 edge is lacking; witness, for example, the much 

 higher concentration of known submarine can- 

 yons in thebest-soundedregions--UnitedStates, 

 Europe, and Japan. The world distribution of 

 submerged terraces is even less well known 

 than are canyons, because terraces require bet- 

 ter soundings. Although probably no new large 

 canyons will be found on the Atlantic coast, it 

 is likely that new soundings and seismic profiles 

 will reveal the presence of and much about the 

 nature of submarine terraces. This knowledge 

 should stimulate interest in further investigation 

 of the extent and depth of such terraces elsewhere 

 in the world. Similarly, the presence or absence 

 of a blanket of sediment which extends from the 

 Continental Shelf down the continental slope will 

 indicate whether or not this slope progrades by 

 deposition. Such conclusions can be applied to 

 other areas after a relatively small effort is 

 spent on testing in these areas. 



Local structures such as faults and folds can 

 generally be expected to be associated with 

 structures known on land. However, the great 

 tectonism of many continental slopes suggests 

 that other kinds of folds and faults may be as- 

 sociated with the outer Continental Shelf and 

 the slope; such structures may be closely re- 

 lated, and found in this environment in many 

 parts of the world. The deeper seated downfolds 

 of crustal rocks beneath the Continental Shelf 

 and slope off the Atlantic and Gulf coasts of the 

 United States and off England may be a common 

 characteristic of continental margins to be dis- 



covered elsewhere when adequate seismic 

 studies are made. 



Sediments on outer continental shelves and 

 slopes have a family resemblance throughout 

 the world, because modern detrital sediments 

 generally have not yet covered those relict from 

 glacially lowered sea levels. The same lack of 

 cover by modern detrital sediments has per- 

 mitted the accumulation of slowly deposited 

 organic and authigenic sediments near the shelf 

 break. Comparison of sediments on the Atlantic 

 shelf with those of fairly well studied areas in 

 the same latitudes off southern California and off 

 the Asiatic coast (Niino and Emery, 1961) should 

 provide evidence of the controls exerted by water 

 temperature and salinity and by contributions 

 from land. These inferences can subsequently 

 be applied more certainly than in the past to es- 

 timation of facies control within ancient strata. 

 Fortunately, the Atlantic Coastal Plain and Con- 

 tinental Shelf are underlain by Tertiary sedi- 

 mentary rocks which were probably deposited 

 in an environment somewhat similar to the ex- 

 isting one. Therefore, application of the knowl- 

 edge gained from modern sediments can be ap- 

 plied directly to ancient strata. 



In the same vein, sedimentary structures sim- 

 ilar to those in modern sediments have been 

 used by Potter and Glass (1958) to infer the en- 

 vironment of deposition in ancient sedimentary 

 rocks. These structures are among the most 

 obvious features of rock outcrops studied by land 

 geologists. Not only have they been helpful in 

 determining environments, but they also have 

 aided in deducing the ancient geography. Similar 

 sorts of structures will be encountered in the 

 cores taken on the shelf and slope. Here we will 

 have an opportunity to see what types of struc- 

 tures are indicative of different environments, 

 through correlation with other properties such 

 as type of benthic fauna present. 



Studies of the types outlined above must be 

 regional in extent even though based on widely 

 spaced samples. Detailed studies of small areas 

 cannot have the necessary breadth of land and 

 sea-floor environments. The Atlantic Continen- 

 tal Shelf is sufficiently large for this general 

 framework study, because it covers 20° of lat- 

 itude and has an area equaling that of all the 

 New England states plus New York and Pennsyl- 

 vania, or 5 percent of the total United States. 

 The continental slope, of course, has an addi- 

 tional large area, and the continental rise even 

 more. 



The labor of constructing a general environ- 

 mental framework is such that many interesting 



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