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which is close to the west. In the railway cutting faulting is observable, but again no igneous 
rocks are to be seen. A mile or two to the west of the line, Mount Lawton and the Mooyonee 
peaks rise sharply out of the rolling country. Bo far as we can discover, they have never been 
examined, but they look like outcrops of igneous rocks, probably basalts. II so, there may be 
a concealed dyke or sill close beneath the surface at the quarry. Similar porcellanites were observed 
near Beaudesert, where the cause was undoubtedly an underlying sill. Dr. Jensen tells me that 
he observed a similar occurrence near Taroom, and thinks that it may ha ve been caused by an escape 
of natural gas which took fire and fused the surrounding rocks. There is no trace of gas escaping 
at present, and I think that the brecciation and fusing is too marked to be due to this cause. To 
produce the effects observed, the volume and pressure of gas would necessarily be great. 1 have 
seen gas escaping in great volume and under great pressure from beds not unlike those south of 
Juandah, but the result was that a very distinct crater was formed, and of this there is no sign. 
Such craters are usually circular and funnel-shaped. I have seen them between 30 and 40 feet 
in diameter and at least 20 feet deep. I think there would be some sign of crater formation if 
this occurrence was due to the escape and burning of natural gas. I am therefore inclined to believe 
that the phenomenon is due to the concealed presence of an igneous intrusive or spontaneous 
combustion in the underlying coal seam. 
Dr. Jensen's traverse northward from Roma to beyond Injune represents the facts so far 
as I can judge. Our own observations made during a comparatively short stay in this district 
closely agree with his. Coal seams of inferior quality outcrop in, what he would call, the Upper 
Walloons, a few miles north of Roma. In his Lower Walloons a 5-ft. seam of coal of good quality, 
associated with highly carbonaceous shales, has been found in two bores about 2 miles south of 
Injune in shafts about 80 feet deep. A similar seam was found at (funnewin, about 400 feet 
below the surface, 8 or 9 miles south of Injune. This is apparently the same seam, so the Walloons 
have a general dip to the south of about 40 feet to the mile. 
Coal seams are also exposed south of the Divide in Bungil Creek and its tributaries, Downfall 
Creek, Bungeworgorai Creek and its tributaries, Flagstone Creek, possibly in the Lower Walloons, 
though their position south of the Divide and their proximity to a thick bed of massive sandstone 
suggests a Middle Walloon horizon. The dips generally are to the S.E., though there is some 
evidence of both folding and faulting in places. The bore near Ounnewin passed through speckled 
sandstones, the specks consisting of small fragments of carbonaceous matter scattered through 
5. Folding in Coal Seam. Walloon Coal Measures, Bungeworgorai Creek, Orallo District. 
Photo., A. W. 
the rocks. We found similar sandstones outcropping a few miles to the west of Ciumewin. We 
were fortunate in finding the cores of the bore at Ounnewin, though it was impossible to get a 
section of the beds from them which would, have been useful. The cores show, however, that 
bands of dark and highly carbonaceous shales are interbedded with the speckled sandstones. 
The beds are just as lenticular and false-bedded as in the Juandah district, a good section showing 
this being observed in a gorge on the Bungeworgorai Creek, some miles to the N.W. of Orallo. 
