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VERNON J. HENRY, JR. Marine Institute and Department of Geology, University of Georgia, Sapelo , Georgia 31327

Origin of Capes and along the Southeastern of the United States: Reply

The comments of E. M. Hopkins concerning tive field testing. We felt the latter mode of several aspects of our recent paper are ap- origin to be worthy of serious consideration, preciated. They raise some interesting ques- deductively based on analysis and in- tions that can only be answered by detailed field terpretation of the events and processes that studies and suggest that a problem of semantics have occurred since the late Pleistocene. Our apparently exists concerning the use or mean- hypothesis considers that the Carolina capes ing of the subject terms. and shoals are such only as a consequence of the We should have defined the terms capes and last rise of the ; the capes being the subaerial shoals in the sense used in our article. Accord- manifestations of the original geological ing to the Glossary of Geology and Related Sciences deposit and the shoals being the submarine (American Geological Institute, 1957, p. 43 counterparts. Certainly, modifications have oc- and 264) a is "a relatively extensive curred and are now occurring in both environ- area jutting seaward from a or large ments. In the areas, for example, island which prominently marks a change in, or cut-and-fill processes are at work, and wave and interrupts notably, the coastal trend; a promi- ripple formation have probably nent feature"; and a shoal is defined as "a part obliterated all vestiges of the original features, of the area covered by water, of the sea or at least superficially. or , when the depth is little; a always Although each of the Carolina capes has a covered, though not deeply." Other, similar, corresponding shoal, this is not to imply that definitions are given and one could take issue capes and shoals are not found independent of with a shoal always being covered by water or, the other, or that capes and shoals found else- for that matter, the difference between a bar where do not have other modes of origin. A and a shoal. For the purpose of our report, detailed study of the geometry and internal however, the definitions given here provide a structure of the Carolina shoals and capes is reasonable enough description for the features needed before proof of origin can be ascer- in question. In essence, a cape is a subaerial tained or the subsequent development under- feature while a shoal, largely, is a submarine stood. It is hoped that subbottom profiling and feature. It is important to understand that the deeper sampling will help provide much of the above definitions are nongenetic and, hence, information required. do not imply any particular mode of origin or chronological relationships; rather, they are based on topographic or spatial expression. Re- placing the word "capes" with "shoreline per- REFERENCES CITED pendicular shoals," as suggested by Hopkins, does not provide any clearer meaning or more American Geological Institute, 1957, Glossary of accurate description for these features. geology and related sciences: Washington, Whether the Carolina shoals are contempo- D.C., National Academy of Sciences-National rary submarine features epigenetically related Research Council Pub. 501, 325 p. to the capes, or relict subaerial features now MANUSCRIPT RECEIVED BY THE SOCIETY MARCH 9, 1971 mostly submerged and being modified by ma- CONTRIBUTION No. 222 OF THE UNIVERSITY OF rine processes, is yet to be proved by quantita- GEORGIA MARINE INSTITUTE

Geological Society of America Bulletin, v. 82, p. 3541-3542, December 1971 3541

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