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places. Reverse dips were noted both near Juandah and lnjune, and again with less certainty 
north of Orallo, though time would not permit of any attempt to follow up such indications. 
Dr. Jensen, with more time at his disposal, thinks that dome -like structures are present, for 
example, near Flagstone Creek, N.W. of Orallo, and near the head of Bungil Creek, while Mr. Ball 
tells me that he noted evidence of a similar structure in the neighbourhood of Tambo. Detailed 
mapping is the only Way in which the existence of such structures can be confirmed and made 
certain. Some of the rounded hill forms have been taken as evidence of dome-like folding, the 
depressions being considered to be the corresponding basins in the strata. While this is sometimes 
true, it cannot be taken for granted unless confirmed by evidences of clip. In one or two cases 
we found evidences to show that hills might be formed by local thickenings in massive sandstones 
as on the Bungeworgorai Creek. Rather as a coincidence, we also found in the gorge section 
in the same creek some evidence of local folding underlying associated hill forms. Again, the 
hill immediately S.E. of the village of -Juandah is rather synclinal than otherwise, so that our 
observations show that the determination of low folding by hill forms cannot be altogether relied 
upon in this area. The general southerly and south-easterly dips of the Walloon strata has 
already been referred to. The outcrops form part of the edge of the (treat Artesian Water Basins 
of Central Queensland, some of the sandstones constituting the intake beds for the water supplies 
which lie at great depths in the centres of the basins. 
C. Surface Deposits. 
A few brief notes on some of the surface deposits may be of interest. 
Pebble beds are widely distributed over the surface between Miles and Taroom, and again 
in parts of the area north of Roma. A noteworthy concentration of pebbles is to be seen in a 
quarry about lmile west of Miles. My notes show that I first considered them to be river gravels, 
but their wide distribution made this difficult to accept subsequently. The pebbles consist 
chiefly of red quartzites, white quartz, some decomposed porphyrite and much silicified wood, all 
rounded and waterworn. The quartzites, quartz, and porphyrites appear to have travelled from 
the north-east, where there are outcroppings of similar rocks. The silicified wood need not have 
travelled far, for it occurs both in the sandy shales of the Walloons and the Marine Cretaceous 
above. Some specimens are facetted in a way that suggests ice action, while others very distinctly 
have the form of wind facetted stones often found in desert areas. The word Dreikanter ” 
has been applied to some of these forms, but some authorities limit the term to one particular 
shape of wind-facetted stone regardless of the fact that all the other forms are but modifications 
of the “ Dreikanter ” form caused by the shifting of the stone on the surface under the action 
of the wind. Coining a name, we might call these “ Aeoliths " or “ Aeocoigns.” 
These beds may represent old river courses, and, if so, would indicate that the major 
tributaries of the Darling once extended over the present “ Divide,” their head waters having 
been captured by the streams now flowing north from the “ Divide.” The “ Divide ” would 
therefore, be of comparatively recent origin, due probably to changes in elevation in this part 
of the continent. 
On the other hand, these pebble beds and scatters of pebbles may be remnants of a basal 
conglomerate due to the wearing back of a cover of Marine Cretaceous from over the Walloon 
belt, and the pebbles which suggest glacial facetting may have been derived from the Permo- 
Carboniferous deposits which lie to the north-east. 
D. Igneous Rocks. 
The Walloon country is not unduly disturbed by the intrusions of igneous rocks. Andesitic- 
basalts have pushed through the Walloons and form the bold mountains which run northwards 
from the neighbourhood of Toowoomba, and are known as the Bunya Mountains, east of Dalby. 
Another large area of basalt occurs to the north of Roma, being especially well developed in Mount 
Hutton and in the Carnarvon Range. Between these points several minor developments of 
basalt and porphyrites occur, some of which have not yet been mapped. A basalt dyke cuts 
through the Middle (?) Walloon strata at Gunnewin, a few miles to the north of Orallo. "Patches 
of basalt have been observed also at one or two places in Gubberamunda and near Yingerbay, 
eastward of Orallo. The Mooyonee Peaks and Mount Lawton, south-west of Juandah, are 
suspected to be basaltic hills, but they have only been inspected from a distance so far. However, 
wide areas are free from any sign of igneous intrusives, which cannot have affected the oil-bearing 
possibilities of the strata in this region to any serious extent, 
E. Petroleum Surface Evidences. 
Any one who attempts to form an opinion as to the existence of petroleum in commercial 
quantities in the Walloon strata of this part of Queensland from surface evidences must find 
himself faced with very great difficulties. Tn the first place, no seepages of either oil or natural 
