Preliminary Soil Mineralogy Studies on Krasnozems in the 
Innisfail District of North Queensland, Australia 
N. H. Monteith 1 
ABSTRACT : A preliminary investigation of four soil series of the Pin Gin family 
of krasnozem soils has confirmed the results of field observation on their history 
and has pointed to the diverse nature of their origins and weathering processes. 
The weathering pattern and origin can account for differences in their fertility in 
the virgin state. 
Studies of the mineralogy of soils can lead 
to a better understanding of the origin and 
history of soils and to predicting their physical 
and chemical behaviour as a medium for the 
growth of plants. Sherman (1955:110) has dis- 
cussed this aspect in relation to krasnozems in 
Hawaii. With this in mind the author, in 1962, 
commenced an investigation of soils in the sugar 
cane growing area of Goondi near Innisfail, 
Queensland. Soils were classified and mapped, 
and samples were taken from modal profiles 
for further study. 
This paper describes the investigations car- 
ried out on the Pin Gin family of soils which 
are classified as krasnozems (Stevens, 1953: 
24-26), latosols (Cline, 1955:70), or oxisols 
(soil survey staff, U.S.D.A. 1960:238-247). 
Other workers have examined the mineralogy 
of North Queensland soils. Leverington (1955: 
9) reported on several alluvial samples near 
the Goondi area. Simonett (1961) and Simonett 
and Bauleke (1963) related rainfall to the 
weathering mean in a detailed study of several 
krasnozem profiles in the Cairns-Atherton re- 
gion. Robinson (1964) has studied samples col- 
lected by Teakle (1950) on the Atherton Table- 
land. He established that there was a relationship 
between mean annual rainfall and the presence 
of gibbsite. The work both of Simonett and of 
Robinson confirmed that of Tanada (1951) in 
Hawaii, who showed a similar relationship of 
weathering stage to mean annual rainfall. 
1 The University of New England, Armidale, 
N. S. W., Australia. Manuscript received March 12, 
1965. 
SOIL DESCRIPTIONS 
The soils are developed in an area of approxi- 
mately 1 40 inches rainfall per annum. There is 
a distinct dry season from May to December. 
The Pin Gin family has been classified into 
four soil series on the basis of texture as de- 
termined in the field, the occurrence of gravels, 
and the presence of euhedral quartz. Tentative 
conclusions on the origin of these soils were 
drawn from field observations. 
Pin Gin Series ( Darveniza Farm ) 
0-7 inches. Yellow-red (dry) 5YR 4/6, 
dusky-red (moist) lOR % loam. Moderate 
fine granular structure. Friable when moist, 
slightly hard when dry. 
7- 48+ inches. Yellow-red (dry) 5YR 4/6, 
dusky-red (moist) lOR % loam. Gradually de- 
veloping to fragmental structure which is 
friable when moist. Infrequent fine clear quartz 
at depth with occasional gravel. 
This soil generally grades into weathered 
olivine basalt at lower depths. The basalt origi- 
nates from several vents on the eastern and 
western edges of the Johnstone River Valley 
which were formed in recent times, after the 
main tableland eruptions. 
Eubenangee Series ( O’Connor Farm) 
0-8 inches. Yellow-red (dry) 5YR 4/6, dark 
red-brown (moist) 2.5YR % loam. Weak fine 
subangular blocky structure with friable to firm 
consistence. Infrequent gravel. 
8- 33 inches. Dusky-red (moist) lOR 3/3 
loam. Weak fine granular structure with firm to 
friable consistence, gravel common. 
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