13 
been determined as Thinnfeldia, which is taken to indicate a Triassic horizon. Other fragments 
from a depth of 510 feet in borehole 1 also indicate beds of Mesozoic age, but are not sufficiently 
well preserved to determine the horizon. 
Looking at the area in a general way, the Post-Tertiary deposits appear to have accumulated 
in a basin-like tract of country formed by a depression in the older sedimentary rocks of the Ipswich 
formation. 
B. Petroleum. 
Mr. Ball* gives the logs of six boreholes which have been sunk in the vicinity of the beach 
by two prospecting companies. Five are grouped about 21 miles north of Tewantin, the sixth 
being about 25 miles north. They vary in depth from 37 feet to 678 feet. For the purpose of 
this Report, the log of the sixth bore will be quoted, in a modified form from Mr. Ball’s reports, 
since it penetrated to a greater depth than any of the others, and, therefore, gives a better idea of 
the underlying strata. Mr. Ball is himself quoting from the field log as kept by the field manager, 
adding a few interpolations of his own : — 
Borehole No. 1 N. 
To 165 feet 
At 165 feet 
To 183 feet 
At 183 feet 
To 197 feet 
To 211 feet 
To 239* feet 
To 249 feet 
To 263 feet 
At 265 feet 
To 300 feet 
To 305 feet 
To 383 feet 
To 398 feet 
To 409 feet 
To 496 feet 
To 517 ft. 3 in. 
To 523 ft. 6 in. 
To 537 feet 
To 560 feet 
To 581 feet 
To 590 feet 
To 605 feet 
To 632 feet 
To 641 feet 
To 653 feet 
To 678 feet 
(of the Queensland Coastal Oil Concessions, North, N.L.) — 
Sand. 
Clay and sand with some wood. 
Red sandstone with clay and pink shale. 
Waterworn pebbles. 
Hard rough sand with gravelly quartz (non-bituminous), a little water showing oily 
substance at 185 feet. 
Soft clay, sandstone, and shale. Oil (greasy stuff) showing freely on water. 
Very hard sandstone with shale bands. No sign of oil. 
Hard sandstone with some seams of clay. Oil and black scums on water. 
Dark non-bituminous shales. t Analysis bitumen 0.007 per cent. 
Soft sandstone. Brown scum showed only in spots. 
Dark-blue and grey shales, bituminous in places. Some thin coal streaks. 
Coarse, hard sandstone and shows of oil and gas.J Plenty of oil and gas bubbles. 
Hard brown, black, and grey shales- — darker shales sometimes bituminous. Grit band 
with clean bright coal attached at 345 feet. 
Very hard sandstone. Some oil showing in places ; little oil showing except in last 4 feet. 
Hard grey shale and sandstone. At 403 feet sample of sludge (Smith’s), 0.015 per cent. oil. 
Very hard grey sandstones and grits. Some thin coal seams. Oil showing. At 413^ feet 
scum on bailings shows oil. 
Sample from top water 
Sample from bottom 
At 414 feet — Sample of sludge skimmings 
At 415 feet — -Sample of sludge skimmings 
At 4151 feet — 
Taken before closing down at night — 
Top water scum 
Bottom 
Samples taken after closing down at night — 
Top water scum 
Bottom 
At 428 feet — Smith’s sample 
At 447 feet — Top water scum 
At 448 feet — Top water scum 
At 4481 feet — Top water scum 
At 452 feet — Top water scum 
At 497 feet — Mr. Campbell’s sample, black coaly scum 
Hard brown shales with thin coal partings. Heavy oil showing at top, little oil below 
Hard grey sandstone with thin coal seam. Little oil. 
Hard brown shale and sandstone with thin coal seams. Little oil. 
Hard brown and grey shales. With little oil. 
Hard grey sandstones and shales with thin coal partings. No oil. 
Brown shale. Oil showing freely. 
Hard sandstone. No oil above. Waxy scum at base. 
Hard black, brown, and grey shales. Little or no oil. At 608 feet shale bituminous. 
Hard grey sandstone. No oil. 
Brown shale and clayey sandstone with thin coal partings. No oil. 
Hard grey sandstones with a little coal. Some oil showing at base. 
0.002 per cent, oil 
0.012 per cent, oil 
0.008 per cent, oil 
0.037 per cent, oil 
0.011 per cent, oil 
0.002 per cent, oil 
0.011 per cent, oil 
0.006 per cent, oil 
0.073 per cent, oil 
0.006 per cent, oil 
0.136 per cent, oil 
0.101 per cent, oil 
0.167 per cent, oil 
0.21 per cent, oil 
Some of the oil showings ” noted in the boreholes were very light indeed, small specks 
and streaks, which had the iridescent appearance of oil, appearing on the surface of samples of 
sludge and water and disappearing again after standing for a couple of hours. Mr. Ball noted 
such specks and streaks in samples in which the Government Analyst failed to detect any free 
* l.oo. fit., pp. 358-364. 
+ The Government .Analyst reported that Mr. Hall’s sample, skimmed from sludge, did not contain any free oil or petroleum residue, but that the total 
chloroform extract (bitumen) was 0.007 per cent.'(of which 0.006 per cent, was petrolene and 0.001 per cent, asphaltene) derived from a small proportion of finely 
divided coal present. 
} The clayey sludge showed a thin dark film which was stated to flash when touched hv a flame. Careful experimentation proved that there is no flash, 
but that the sudden formation of a clear space about the point of impact is due to surface tension. On close inspection, minute iridescent spots and streaks of 
oil, quite possibly from the tools, were distinguishable. 
