16 
has been sunk for oil on the top of the ridge, rather more than \ mile to the E. of the station. 
The bore is about 85 feet above sea level. The station is 47 feet above sea level, while the top 
of the shales in the quarry is probably somewhat higher than this. Thus the thickness of the 
Tertiary beds present in the borehole is probably less than 38 feet unless something takes place 
between these points which is not observable at the surface. 
The oil bore has been sunk to a depth of 866 feet. Mr. E. C. Saint Smith, of the Geological 
Survey of Queensland, who visited, examined, and reported* on this area during drilling operations, 
classifies the strata passed through into — 
Tertiary — Sandy clays 
i. rt fBundamba. Clay shales and sandstone, with basal con- 
Mesozmc I , , J 
< glomerate 
^fpswich. — Clays, sandstones, and carbonaceous beds 
(Triassic) 
81 feet 
246 feet 
To bottom 
of bore 
Mr. Saint Smith suspects that the clays included in the Tertiary, below 29 feet, may belong to the 
Bundamba, and this is confirmed by the above reasoning from field evidence. Thus the thickness 
should be — 
Tertiary strata . . . . . . 29 feet 
Bundamba . . . . . . 298 feet. 
Below these formations lies an old schistose series which is considered to be of Lower Palaeozoic 
age. These beds outcrop at the surface about 2 miles to the west of the bore, and have been 
proved in a boring for coal about 2 miles to the N.E. at a depth of less than 1,000 feet, so that 
it seems likely that they lie not very far below the bottom of the present borehole. 
B. Petroleum. 
• f 
The site for the borehole was selected by means of the divining rod, the diviner being of 
opinion that large quantities of oil would be obtained in the Tertiary beds. The results obtained 
by drilling rather upset this conclusion, for it is obviously impossible to obtain oil in commercial 
quantities from a thin cover which forms only the capping of a ridge. Even if these beds did 
originally contain oil, it could not be retained in such circumstances. However, this is got over 
by considering the underlying members of the Mesozoic system to be of Tertiary age and by 
naming them according to the various subdivisions of the Tertiary period, the limits of these 
subdivisions and their names still being chosen by the divining rod. 
3. The Bore at Wolston. 
Photo., A. W- 
While there is no question whatever concerning the sincerity of the gentleman in question, 
the methods adopted are not those by which oilfields are likely to be discovered in Queensland, 
and the subdivisions of the strata must still depend upon the evidences supplied by the beds 
themselves, primarily upon fossils, and secondly upon correlations of the nature and sequence 
of strata as between one locality and another. Thus a geologist working on the strata exposed 
in the Ipswich coalfield should be able to recognize the Ipswich series if he should find it in an 
exposure some miles away. It will differ considerably in very many respects from Tertiary strata, 
and no good geologist would mistake one for the other. The structure of the area has never been 
* Saint Smith, E. C. " liming for Oil at Wolston.” — Q.G.M.J., vol. XXIV., No. 273, 13th February, 1923, pp. 56-fiO 
