CHAPTER XXVII. 



THE SOILS OF THE AURIFEROUS DISTRICTS. 



Many examinations and analyses have been made of the soils which 

 occur in various parts of the goldfields and of the districts traversed in 

 journeying to them. The soils found belong to two great groups — the 

 tirst consisting of bed-rock or sedimentary soils which have been formed 

 in sitn by the gradual decomposition of the underlying igneous rocks ; 

 the second the alluvial, jt^olian, transported, or drift-soils, including 

 carbonaceous soils formed largely by the growth of plants. 



Amongst the former group are very widelv distributed soils which 

 lla^■e been produced by the decomposition and degradation of granitic 

 and gneissose rocks, of quartz-porphyries and allied rocks, of chloritic 

 rocks, and of the basic rocks such as mica-gabVjro, epidiorite, horn- 

 blende-schist, and diabase. Several specimens of each of these soils 

 were collected and examined. 



Of the soils of the second class attention has l)een directed towards 

 the so-called " pegass " soils which consist largely of tropical peat ; the 

 ieolian soils on the sand-dunes which form a conspicious feature in 

 places in the country between the goldfields and the coast ; and the 

 alluvial oi' fiuviatile soils found on the Hats of some of the larger creeks. 



SoU)< fo)')7ied in situ — Bed rock Soils. — In some places the soils 

 derived from the acidic rocks, more especially from the granites and 

 gneisses, have undergone more or less extensi^'e re-arrangement, with 

 the result that two classes of soils have been formed — arenaceous, or 

 saud}'^ soils, and argillaceous or clayey soils. In the parts of the colonv 

 examined the quartz-2)t»rphyries and their allied rocks usually form 

 relatively low-lying gi'ound, and the soils derived from them have, as a 

 rule, undergone little re-arrcingement. 



The mean compositions of the soils derived from the acidic gioup of 

 i-ocks were found to be as follows : — 



Stoiios leinoveii bot'ore unalysis 

 Water rctainud bv air-driud soil 



ISoil.s from Granite diid 

 Gneiss. 



Arenaceous. Artrillaceous. 



4-2 

 4-7 



nil. 



ISoitti from 

 Qunrtz-For- 



phiirtj and 

 allied Eocl's. 



4-6 



