292 GEOLOGY AND PETROLOGY OF THE GREAT SERPEXTIXE BELT OF N.S.W. 



of struetui-e introduced by faulting, can be i)aitl\ realised from a t-ousideratioa 

 of tbe features of the Currabubula district. 



The Geology of the CuRRABunvLA District. 



Previous Investigation. 



Tile tiist account of this district was given l)y Sir T. L. Mitchell in 1831 

 (1, p. 31), in the following words: "The country appeared tolerably open and 

 level, so that we could pursue our course in one direction nearly eight miles. 

 The most conspicuous hiU on our right was named by the native "Barragundy." 

 It was \-isible during the whole of our day's journey. We at length entered upon 

 an open and grassy plain, and found in the skirts of the wood beyond it a channel 

 containing water in alnindance. and which was known to the natives as "Carra- 

 bobila."* Beyond this channel arose a peaked and picturesque range whereof tlie 

 highest summit was named "Turi." Several guUies were dilTicult for the passage 

 of the carts, and detained the party in its ascent, but at length we reached the 

 top of tlie pass and crossed the range, which appeared to be continuous, thus 

 separating the basin of the Peel from that of the water falling into the Liverin)ol 

 Plains.** We were agreeably surprised to ttnd that the opposite side of these 

 hills, and the whole face of the country beyond them presented a very different 

 appearance from that through which we had passed. A gently sloping extremity 



lay before us for eiglit miles in the dii-ection of our proposed route 



The heights which we had crossed appeared to extend from the Liverpool Range 

 to the northward as far as could be seen; but the native told me tliat it soon 

 terminated on the river 'Callala' (or Peel), whose course he said turned west- 

 ward." 



The Rex-. W. B. Clarke, twenty years later, determined the height of Turi 

 Peak as 2,952 ft., but made no reference to the geology of the region (10) ; Mr. 

 Etheridge received samples of erinoidal limestone from Glen Donald, four miles 

 east of Currabubula in 1890 (11) ; and in 1905 Mr. Andrews briefly referred to 

 the topogi-aphical features (17). In 1913 Mr. Carne examined the Glnssoptcris 

 sandstones of Werris Creek (18) and Mr. Cambage obtained Itliacopteris near 

 Currabubula (19) . The occurrence of Archaencalamitea was also reported in 

 1914 (20). No connected account of the geology of the region has, Lowever, yet 

 been given. 



The Buritidi Series. 



Tlie eastern iiurtimi of tlie Cuiialmbula region consists of rocks of marine 

 origin. They eomurise a lower and an upper portion. The former is made up 

 of marine mudstones of an olive-gieen colour showing Carboniferous fossils 

 mostly as easts. They contain here and there small lentides of limestone up to 

 a few inches in thickness and a few feet in diameter, and are interbedded with 

 tuffs of intermediate or keratophyric composition, the tuffaceous zones being also 

 at times fossiliferous. Narrow zones of conglomerate or pebbly tuff occur, and 

 locally larger masses of coralline (Zaphrentis) and erinoidal limestones. In 

 general, these beds resemble quite clearly the Burindi rocks in the western slopes 



•Mitchell mills : "Even before iiiy men had seep this .spot, the uative name in their 

 mouths was corruiiteil into 'Teri-ible Billy." Locally this name is now apjilieil to the 

 hill. olHcially teniiod " Wan-ai^umU ' " or "Ten-ililc Mountain." 



•'PioViably Mitchell's party passed thi'ou>;h the ijap north of Duii I'eak. 



