37 



Kiver country, and is frequently said to be one of tlie best pas- 

 toral regions in Australia. 



GEOLOGICAL STRUCTURE. 



Outliers of the Flinders Range. 

 Soon after leaving Beltana in journeying northwards, the 

 Flinders Range begins to break up, and except for the prolonga- 

 tion of the main chain towards Blanche water and a less important 

 spur towards Mount Nor' AVest, the primary rocks of which they 

 are formed ire lost beneath the gypseous clay formation of the 

 Great Plain. Passing round the south and west sides of Lake 

 Eyre, and ascending as high as the Neales River Valley, live 

 outcroppings of granite and metamorphic rocks are met with. 

 By their strike, sequence and composition, as well as their 

 .actual location, there is little reason to doubt but that they be- 

 long to the same system as the rocks forming the Flinders chain. 

 'The outcrops are : — 



1. Finniss Springs. 



2. Mount Margaret. 



3. Peake. 



4. Algebuckinna. 



5. Mount Dutton. 



Each of the localities are on a line, which, while running north- 

 ward, recedes also to the west, so that the general direction of a 

 line connecting them would be JS'.W. and S.E. 



1. Fixxiss Sprixgs. — At this locality a ridge of quartzite forms 

 .a low continuation of the Mount Nor' West Range prolonged 

 through Hermit Hill. It forms good building stone, and from 

 it the culverts and railway buildings along the line have been 

 constructed. 



2 AXD 3. Mount Margaret axd Peake Raxges. — The out- 

 crops at Mount Margaret and the Peake form the basal portions 

 of the Denison Range, which runs from Anna Creek Station to 

 Mount Kingston North, a few miles north of the Peake Telegraph 

 Station. This range is of irregular outline, and composed of two 

 very distinct systems of rocks. The uppermost series is a friable, 

 white, sometimes chalky-looking, sandstone of considerable thick- 

 ness, the upper portion being the most compact. Under it is a 

 stratum of ferruginous cement, at times enclosing fragments of 

 white and opaline quartz, at others being built up of ironstone 

 nodules several inches in diameter, but which are simply crusts 

 filled with white siliceous sand in a minute state of subdivisioii. 

 This band of cement is but from a few inches to about five feet 

 in thickness, and in turn rests on sandy argillaceous beds which 

 graduate into a brittle blue clay weathering to olive-green in 



