PUTNAM 



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sedimentary rocks, that these rocks are flat-lying, and that the surface of the plain was shaped 

 by ice scour. Therefore, one can expect a wholly different set of operational consequences here 

 than would be encountered on a geometrically similar plain shaped by streams and located in a 

 tropical region. 



These coastal types determined by the major landforms present in a 5- or 10-mile wide 

 strip do not convey the whole picture, however, in spite of a rich variety stemming from various 

 combinations of structures and climates. Shore features, though much more limited in areal 

 extent, are often of equal or greater military importance. They are, in effect, obstacles form- 

 ing a narrow fringe between the open sea and the particular major coastal landform with which 

 they are associated locally. We therefore recognize a second category of coastal types— those 

 determined by shore features (Fig. 2). Properly included in this category are such things as 

 kelp beds. Dense kelp fouls propellors, makes maneuvering of sniall craft extremely difficult, 

 and otherwise causes serious problems in amphibious operations. Coral reefs belong here too, 

 as a lot of hard-won experience gained in the last war will testify. Tidal woodland in Fig. 2 

 refers not to mangrove swamps exclusively, because there are other kinds of coastal vegetation 

 that also extend into the sea. 



Beaches other than barrier beaches are being excluded from our classification and map 

 because they are the subject of highly detailed operational intelligence studies conducted by the 

 military. Furthermore, a great many beaches are of extremely limited linear extent. 



Shore feature coastal types can be shown on the world map by the use of suitable carto- 

 graphic techniques, though they will necessarily have to be exaggerated for such small-scale 



Figure 1. Classification of Coastal Types Determined by Major Landforms (By J. T. McGill) 



