20 FOYE. 



volcanic rock and, during a period of oscillatory movements, several 

 hundred feet of marls and claystones with occasional thin seams of 

 coal were deposited. 



6) This period was followed by one of more decided submergence, 

 during which approximately 150 feet of coralliferous ^ (?) limestone 

 was laid down. 



7) The limestones and older rocks Avere then uplifted, folded, 

 faulted, and eroded. 



8) A period of volcanic activity followed, during which andesitic 

 flows and ash buried the eroded sediments. 



9) A period of erosion followed. 



10) The eroded hills of andesite were submerged along the edge of 

 the island and a series of coastal sediments was deposited. 



11) The island was then difPerentially uplifted and eroded. 



12) Post-Glacial outbursts of volcanic activity built up the islands 

 of the Yasawa group and injected dikes into the coastal areas of south- 

 western Viti Levu. 



13) Recent differential movements have uplifted the coasts of ^'iti 

 Levu and at the same time depressed the Yasawa islands. 



Eastern Viti Levu. 



Having outlined the history of western Viti Levu, the eastern part 

 will now be described and its history compared with that of the west- 

 ern side. 



The south-central coast of Viti Levu, between the Singatoka and 

 Navua rivers, is formed of maturely dissected andesitcs. Sediments 

 of the uplifted coastal plain, usually marls, surround the volcanic 

 hills as far east as Serua Bay, along a coastal strip 25 miles 

 in length. The sketch (Figure S) shows the uplifted marls near 

 Tangani, where they overlie ash and agglomerate beds and dip 12° 

 to 15° S. E. 



The accompanying map (Figure 9) illustrates the topography of 

 the Navua delta plain. This plain is some 10 miles long and miles 

 wide. It is dotted here and there with hills of andesitic rocks. Manv 



1 The writer found no corals in these limestones except in the basal beds 

 underlying the marls. Workers in tlie Lands Department report corals in 

 place, however, near the head waters of the Navu:i river, in limestones belong- 

 ing to this series. 



