2 Raised coral reef; low linear rough surfaced ridge along shore, 

 backed by lower flat land. Movement and road construction easy. 



Sand dunes. Movement and road construction moderately 

 difficult. 



Terraces. Movement and road construction easy, except at 

 scarps (shown by hachured lines). 



4a. Movement impeded only by scarps; friable clay soil; terrace 

 surfaces even. 



*» 



4b. Movement impeded by sticky clay soil; surface rolling. 

 Scarps. Hachures point down slope. 



Fig. 1. Terrain map (sample from strategic engineering study prepared by 

 Military Geology Unit, U. S. Geological Survey). 



