7. Conclusions. 
i am afraid, therefore, that we cannot consider even the most promising of the structures 
yet discovered in the Sydney Basin as possible sources of commercial supplies of petroleum, 
but there is hope that natural gas may be found. The beds underlying both the Loch invar and 
the Bedford Domes contain possible source rocks and porous reservoirs. In view of the fact that 
the Lochinvar structure is so broken, I consider that there is a strong probability that any gas 
which may formerly have been present has escaped. The Belford Dome is practically unbroken 
so far as 1 can discover, though it is bounded by faults in the synclines. I think that this dome 
should certainly be tested for natural gas. 1 can find no serious feature which is unfavorable 
to its occurrence in this structure. Moreover, there is the additional advantage that the 
extension of the Greta coals in this direction will be proved, which may alone justify the work. 
It may be necessary to drill deeply into the Lower Marine Series to effectively test the area, but 
a boring to about 3,000 feet should accomplish all that is necessary. 
Small coal basins in the Upper Coal Measures exist to the north-west of the Belford area, 
in which the carbon ratios appear to be' pretty consistently lower than 60. This district should 
be prospected for structural conditions with a view to testing the area for natural gas, while 
there is some slight promise that small oil pools may also have been preserved if favorable 
conditions should be proved to exist. 
8. Summary of Conclusions. 
1. On various grounds 1 have come to the conclusion that the permo-carboniferous system 
of the Sydney Basin constitutes the best field for exploration for oil in the State of New South 
Wales. 
2. That the Upper Marine and Lower Marine Series of this system contain the most 
likely strata for the production of oil or natural gas. 
3. That the most likely area is the Hunter River district on the northern and north-west 
margins of this basin. 
4. That horizons which may possibly have been sources of oil and gas exist in the strata 
in this area, together with possible storage beds, and that at least one structure exists which is 
eminently suitable. Prospecting for similar structures should be carried out in the north-western 
corner of the basin. 
5. That apart from the faulted nature of much of the country, the carbon ratios in the 
coal measures are for the most part too high for the occurrence of petroleum in commercial 
quantities in any part of the basin. 
6. That the apparently suitable carbon ratios obtained from coals in the Lower or Greta 
Goal Measures are misleading owing to the nature of the coals due to peculiar mode of origin and 
to the presence of oannel and semi-cannel coals and kerosene shales in the coal seams. Normally; 
the carbon ratios should be represented by a much higher figure. 
7. That the Belford Dome should be tested for natural gas by drilling to at least 3.000 
feet, and that in addition to possible gas supplies of great commercial value, this boring should 
also prove a. workable extension of the, Greta Goal Measures, which provide the best export coals 
in Australia. 
8. That there exists to the west and north-west of Belford areas in which the carbon ratios 
in the Upper Coal Measures are apparently more or less consistently below 60, and that these areas 
should be prospected in order to determine whether suitable structures exist that may be tested 
for supplies of natural gas ; and that there may be some slight hope of the occurrence of small 
pools of oil in such structures if conditions should be proved to be favorable. 
SECTION II. 
Notes on the Kerosene Shale Deposits of New South Wales, with a Special Reference 
TO THE Wo LOAN V ALLEY WORKS. 
Within a hundred miles of Sydney there exist very large deposits of the richest kerosene 
shales known in the world. At present little is being done to develop them. In the Wolgan 
Valley the mines are falling into decay, the luigh retorts are empty, and the value of the great 
distillation works is depreciating rapidly for want of use. This regrettable state of affairs is 
due to many causes, the chief of which are the rise in the costs of operation and production since 
pre-war days, and from this has followed the inability to compete with imported well oil products, 
even though these also have risen in price. Initial errors made by some of those who started 
the enterprise at its present location have also exercised adverse influences. Future operation 
of these works may be of such importance to Australia that some brief notes, based on a personal 
visit to the W olgan Valley district, may be of service. 
