440 A CONTRIBUTION TO THE GEOLOGY OF VITI LEVU, FIJI, 



reasons I am not inclined to believe the Rewa soapstones older 

 than Pleistocene, though it is possible they may be as old as 

 Pliocene. In the absence of further data the correlation of the 

 Rewa soapstones with those of Walu Bay cannot be considered 

 proved. 



Nowhere in this area have basal beds of the soapstone series 

 been observed, so that, in the absence of fossils, their strati- 

 graphical relationships are obscure. In the deep creeks just east 

 of the Medrausucu Range, the lowest rocks encountered are 

 jointed andesites, but these are in all probability intrusive into 

 the soapstones. 



Summary of Section i. — The greater part of the 

 area is covered by level-bedded " soapstone " containing traces 

 of plant fossils and representing redistributed tuffs. These form 

 an extensive plain, with an average elevation of some 300 feet. 

 In the surface of this plain the rivers occupy canon-like valleys. 

 At the head of the Rewa Delta the high-level plain is broken 

 into mesas with an altitude of about 100 feet. The delta is very 

 extensive, and this, together with the occurrence of reef-limestone 

 well within the mangrove belt, proves that there has been no 

 notable change in sea-level for a considerable time. No solid 

 rocks of any kind occur in situ anywhere in the region except 

 just at the base of the Medrausucu Range. 



ii. — Medrausucu Range. 



I have taken the liberty of referring to this remarkable range 

 of mountains by an abbreviation for the name of its two most 

 prominent peaks, Medrau sucu basaga. The range is a most 

 striking feature from all points of view. Its eastern face, as 

 seen from the Rewa Plateau, is almost precipitous throughout 

 its entire extent. It is strikingly linear in character, extending 

 for many miles in a N.N.W.-S.S.E. direction. It stretches 

 from the south coast a little west of Suva, to Nacau, a 

 mountain just north of Naivucini, a town at the junction of 

 the Wainimala and Wailase Rivers. At its southern end it is 

 not sharply defined from a number of other mountain ridges, 



