PHYSIOGRAPHIC EVOLUTION OF NEW CALEDONIA 



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fall ... of considerable height, coming down a channel it had worn 

 for itself on the mountain side, and finally falling over a steep cliff into 

 the sea" (1873, 326); but he went no farther: a cascade on an island 

 rim a simple cascade was to him, and it was nothing more. 



It is conceivable that the cliffs of the New Caledonian coast are due to 

 a great fault, but as well as I could judge by careful scrutiny from the 

 deck of a passing steamer and from excursions ashore at several points, 

 no associated step-faults are to be seen in the uplands back of the cliff 

 top, and this suggests that the cliffs were cut by the waves while the island 

 stood higher than now. The cliffs are repeatedly breached by branching 

 embayments, the rock-bottom depth of which was estimated at 600 or 800 





Figure 16. — Evolution of the Coasts and Reefs of New Caledonia 



feet. Thus the total height of the cliffs may be from 1,000 to 1,800 feet. 

 The abraded rock platform in front of the cliffs might well have a breadth 

 of 5 or 10 miles, for the seaward slope of the uplands back of the cliff 

 tops is moderate. Deltas are now filling the bayheads, fringing reefs are 

 growing along the shoreline on the face of the partly submerged cliffs, an 

 imperfect barrier reef rises 5 or 10 miles offshore, and the lagoon has a 

 depth of 30 or 40 fathoms. 



In strong contrast with the clift northeastern coast, M, figure 16 (look- 

 ing west), the southwestern coast of New Caledonia descends with gentle 

 slopes to a greatly embayed shoreline, L, bordered by fringing reefs, ex- 

 cept where deltas of the current cycle of erosion prevent coral growth, 



