GEOLOGICAL OBSERVATIONS IN FIJI. 33 



Southern Coast of Vanua Levu. 



Only two sections of the southern coast of Vanua Levu were seen 

 by the writer. Each of these was 15 or 20 miles in length and con- 

 tained areas of uplifted limestone. The first section runs along the 

 southern side of the Waikava peninsula at the southeastern end of 

 the island and extends westward for 5 or 6 miles beyond Fawn 

 Harbor. The second section was made in the vicinity of Savu Savu 

 Bay. 



Crossing the Waikava peninsula from the river flat at the head of 

 Mbutha Bay, the land rises to an elevation of 1200 feet within the 

 space of a mile. Near the divide, the peninsula, composed of andesi- 

 tic ash and agglomerate, presents a sub-mature topography. 



As one approaches Fawn Harbor from the east, the highlands of 

 agglomerate retreat gradually from the coast, and a wave-cut bench 

 appears at an elevation of 75 to 80 feet. The agglomerates below 

 the bench level are overlain by fine ash deposits containing some 

 sea shells and a calcareous matrix. The ash unconf orraably mantles 

 the domes formed by the late-mature dissection of the agglomerates. 

 A series of islets, composed of ash and agglomerate, cross the mouth 

 of Fawn Harbor. The bay-heads at either side are underlain by 

 loose, fine, volcanic marls, which have been benched by the sea at its 

 present level; the resulting platform slopes seaward at a very low 

 angle (3° to 4°). This platform may be traced for a half a mile out to 

 sea. Just west of the western head-land, the loose yellow and red 

 fossiliferous marls are carved into hoodoo stacks standing 15 to 20 feet 

 above sea-level. For a few miles west of Fawn Harbor, the elevated 

 wave-cut bench extends a mile or two inland. Five miles west of the 

 harbor, near the little village of Vunilangi, the seaward border of the 

 bench has a fringe of raised coralliferous limestone. 



The plan and cross-section (Figure 14) show the prevailing condi- 

 tions. Back of an outer rim of raised coral heads, 10 to 15 feet in 

 height and 100 to 200 yards wide, is a wide flat which was formerly 

 covered by 2 to 3 feet of water. Artificial drainage has made the flat 

 dry and arable. The drain-cuttings show that the plain is underlain 

 by a limestone, composed of shell and coral waste with an occasional 

 coral head in place. A hill 60 to 70 feet high rises in the midst of the 

 flat and represents an isolated dome of andesite unconformably over- 

 lain by coralliferous limestone to its summit. 



The relations at tliis place point to very recent uplift. At the time 



