XI • THE KOROTINI RANGE 



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The summit of the range may be described as a " ridgy " table- 

 land. Though about 2 miles in breadth, its level only varies 

 between 2,000 and 2,200 feet, the inequalities being probably the 

 effect of denudation. Here, as in many other similar localities, on 

 account of the dense forest it was only possible to determine the 

 surface-configuration by the use of compass, watch and aneroid 

 The prevaihng rocks displayed in this region are grey non-calcareous 

 basic tuffs, somewhat altered in character, and composed of frag- 

 ments usually not exceeding i mm. in size of a basic glass the 

 palagonitic process being masked by other changes. These tuffs 

 often become brownish-yellow through hydration. Tests of foramin- 

 ifera are enclosed, but they are very scanty. 



On the north slopes basic agglomerates and palagonite-tuffs are 

 the predommant rocks down to the foot of the range. A specimen 

 of the tuffs taken at 1,300 feet is calcareous in patches and probably 

 contams tests of foraminifera ; but it is too much weathered to 

 enable one to speak with certainty on this point. The interestino- 

 eature of this slope is the exposure at 1,600 to 1,700 feet of largS 

 Dlocks of a dark grey hypersthene-augite andesite referred to the 

 orthophyric order of those rocks described on page 290 Lower 

 <Iown (1,000-1,300 feet) occasional solitary blocks of the same rock 

 l)ut somewhat altered, occur imbedded in the palagonite-tuff This 

 type of rock which is characterised by the orthophyric structure of 

 the groundmass and by other features is rarely represented in 

 ^'anua Levu. 



Summing up the general results of this traverse we observe that 



!f'/^'\''^i^'Pf^' °^^^^ range, basic agglomerates, breccias, 

 and tuffs, the last however scantily foraminiferous, occupy a great 

 extent of the slopes and summit. The alteration of these deposits 

 01 the southern slopes is noteworthy. The only deeper seated 

 n lassive rocks observed were the pyroxene-andesites above alluded to 

 (4) Traverse of the Koro-tini Range from Nukumbolo 

 TDSUENL— The hot springs at Nukumbolo, which are described 

 01 page 24, rise up through agglomerate-tuffs. Around the 

 bathing pools he large masses of altered palagonite-tuffs which give 

 te first indication of the region of altered rocks that extends from 

 Nukumbolo to the lower slopes of the range, a distance of about 

 tr ree miles. 



For about a mile and a half or two miles from this place the 

 tr.xk lies through a broken country and does not rise to a height 

 m )re than 300 feet above the sea. A variety of altered rocks are 

 he re exposed in position in the stream courses. Some of them are 



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