84 VOLCANIC AREA OF EAST MORETON, ETC., DISTRICTS, Q., 



a mile to the 1ST.W. of Mt. Cooroora we find ourselves on sandy 

 forest country overlying decayed muscovite granite. This forma- 

 tion continues northwards right to the top of the Woondum 

 Tableland, north of Cooran. The lava of Mt. Cooran has burst 

 through it. The Tuchekoi Range has the configuration and 

 vegetation of volcanic formations, rhyolite, andesite and basalt 

 being probably all represented. 



Steep (rhyolitic) bluffs are seen to be numerous, whilst more 

 rounded hills, on which pine and cedar figure in the scrubs (basalt),, 

 are also abundant. 



The Parish of Woondum, N.E. of Cooran, forms a tableland 

 averaging 1,000 feet in height and reaching 1,500 feet in places. 

 On its south-western slope I met with sandy granitic forest 

 country, which is intruded with numerous dykes of trachyte, 

 rhyolite, aplite, quartz porphyry and basalt. Basalt fills irregular 

 erosion hollows on the tableland, and also caps the higher points. 

 Mt. Pinbarren (1,100 feet), south of Woondum, consists of meta- 

 morphic rocks, with quartz reefs, to a height of about 700 feet, 

 above which it is volcanic. The extrusive rock consists of 

 trachyte and andesitic basalt. The mountain supports a mixture 

 of forest and scrub, the latter covering all the volcanic rock. 



East of Pinbarren the peculiar soft soapy phyllites of the 

 Kin-Kin commence, supporting thick forest in places, and dense 

 vine-scrub in places. The Kin-Kin country is very broken. 



The steep western fall of the Woondum Tableland, which 

 extends miles and miles in an almost straight line, suggests a 

 great fault, with the downthrow of its western side. The 

 eastern slopes of the Woondum present the usual erosion 

 features. 



This fault antedates the formation of the peneplain, but is,, 

 nevertheless, of late Tertiary age, probably coseval with the 

 basalts. 



A few hundred yards on the Gympie side of the Cooran 

 Railway Station there is seen in the cuttings a mass of waterworn 

 boulders, pebbles, and gravels, occupying a definite hollow of 

 considerable width (Text fig.7, r). This is an old river channel, 



