RECORDS OF W.A. MUSEUM. 
[71 
“ 124. The Ord limestones are for the greater part hard and 
flaggy, rarely massive, usually grey in colour, sometimes sandy or 
magnesian, and seldom fossiliferous. In many parts of the district 
they are interbedded with red shales, marls, and sandstones, the 
former of which contain occasionally layers of gypsum, together 
with traces of rock salt. . . . 
“ 125. Over the great part of this country the limestone crops 
out in bare masses, cut through by numerous gullies and water- 
courses, along which the rock forms high cliff's and scaurs, showing 
the stratification — which dips at a very low angle in various 
directions — very distinctly.” 
Dr. R. Logan Jack states': “The strata [of the limestone] 
which at the south-western and south-eastern boundary of the 
formation dip to the north-east and north-west, are practically 
horizontal on the Ord River below its junction with the Elvire, and 
probably continue to be horizontal where they are covered, on the 
left bank of the Ord.” 
These descriptions enable us to define the known outcrops of 
Cambrian limestones of Western Australia as being hard and 
flaggy, usually grey in colour, either horizontally bedded or dipping 
at a very low angle in various directions. 
Evidence of confirmatory nature is found in the record of the 
explorations made by the Government Geologist of South Australia 
and his Staff in 1905. Mr. H. Y. L. Brown reports*: “ During the 
present examination of the belt of limestone, extending south- 
easterly from east of Mt. Litchfield to the Katherine River, was 
proved to be of Cambrian age by fossil evidence. Outcrops of the 
rock, two miles north of Noltenius Billabong, and about nine miles 
from the Daly River, consist primarily of a compact blue-grey and 
yellow sub-crystalline limestone, parts of which are rich in pteropod 
tests of Salterella, weathering slightly in relief. The beds are 
horizontal, and the line of outcrop trends north-westerly. No deep 
section is available, and, wherever encountered, the outcrops rise 
but a few feet above he surface. The physical features are low, 
banked, denuded tables, separated by horizontal joint planes, and 
piled one upon the other, the uppermost being very much smaller 
1 Loc. cit., p. 26. 
Loc. cit., p, 14. 
