DROWNED ANCIENT ISLANDS — HESS 



287 



Though few guyots sliow any suggestion of terraces on their outer 

 slopes, one large guyot near latitude 20° N., longitude 148° E. has a 

 well-developed flat upper surface at 800 fathoms, and projecting from 

 under its southeastern margin there appears to be a terrace or older 

 guyot with a flat upper surface at 1,100 fathoms. In the area between 

 Wake Island and Johnston Island there are a number of normal guyots 

 rising from hilly areas which have numerous flat or nearly flat sur- 

 faces between 1,100 and 1,900 fathoms. These hilly areas with flat or 

 nearly flat surfaces have as yet been insufficiently explored to under- 

 stand the relationships they exhibit. They may represent areas of 

 older, deeper guyots partly buried by sediments, but until a more 

 detailed examination of them can be made, their nature will have to 

 remain rather obscure. Such areas do not appear to be common 



FiGUBE 7. — Relation of Eniwetok Atoll to nearby guyots which are outlined on 



the diagram by dash lines. 



elsewhere. Some of Murray's Gulf of Alaska seamounts possibly also 

 fit into this category. The great majority of guyots rise from the 

 normal ocean floor. 



RELATION OP GUYOTS TO ATOLLS IN THE MARSHALL ISLANDS 



Many guyots are present in close association with atolls in the 

 northern Marshall Islands. The present discussion is centered about 

 Eniwetok Atoll of that group. This atoll apparently rests in part 

 upon two guyots so that the flat upper surfaces of the guyots project 

 out beneath its southern and northwestern slopes resulting in a well- 

 developed bench on those sides at a depth of 700 fathoms. The eastern 

 side of Eniwetok shows a normal atoll slope with no suggestion of a 

 bench, and the central portion of the western side shows similar fea- 

 tures. Figure 7 shows the relationship between Eniwetok Atoll and 

 the nearby guyots, and figures 8 and 9 show two profiles, one approach- 

 ing the passage between Japtan and Parry Islands from the east and 



