SCIENCE AND INDUSTRY. 
) 
The Roma Beret Notes one hee Rcccut 
Flow of Gas. 
By W. E. CAMERON, B.A., Deputy Chief Geologist, Queensland. , 
During the drilling of the present (No. 4) bore in April of last 
year, gas was first noticed by the driller in the bailings from a sandy 
shale from 3,602 to 3,610 feet, and again in sandstones from 3,665 to 
3,677 feet, and from 3,680 to 8,690 fect. As the drilling, following the 
usual Californian practice, was being done with a full column of water, 
exercising a pressure of nearly 1,500 Ibs. per square inch on the gas in 
the top gas stratum, and correspondingly greater pressure on the lower 
strata, the gas could not flow into the bore unless it had a pressure 
exceeding that of this column of water. Not having that pressure, no 
flow of gas was obtained while the column of water remained above it. 
It was not judged advisable at the time to test these strata for gas, — 
as it was not considered that the main gas stratum met with in the 
previous bores had been reached, and no very great flow of gas was 
expected from them, as no gas had been reported at these depths from 
the previous bores. There was also the risk involved in bailing the 
10-in. casing with a column of water of about 3,500 feet standing behind 
it. However, inthe recent repairs to the 8-in. casing, which has become 
fast at the bottom of the bore, the column of water in the bore was 
lowered some 520 feet, with a consequent lowering of the pressure of the 
water column on the gas stratum. This allowed gas to flow into the 
bore for about half-an-hour, the subsequent filling of the casing with 
water shutting off the flow. Subsequently, in cutting the casing at 
3,624 feet, the column of water in the bore was lowered some 880 feet, 
with a consequent still further lowering of the pressure of the water 
column on the gas stratum, which was thus enabled to discharge all the 
water from the bore and flow unchecked, with ‘the consequent revelation 
that these strata contain very much greater quantities of gas than was 
judged possible from the records of the previous bores put down to 
them. ‘ 
Pressure or THE Gas. 
There has been considerable controversy as to the pressure under 
which the gas at Roma exists in the strata. By some the pressure 
has been regarded as insignificant on account of the small flows met with 
in the two previous bores when compared with the enormous yolumes of 
gas met with in oil-bearing strata in other parts of the world. The 
volume of flow, however, is in direct proportion to the size of aperture 
through which the flow takes place. In the two previous bores, the flow 
was seriously obstructed—in the one case by having to pass through a 
column of water of nearly 3,700 feet in depth, and in the other case by 
having to pass a set of drilling tools which were fast in the bottom of | 
the bore, and which nearly blocked its total diameter. The small 
volume of gas, therefore, in these flows formed no criterion of the 
content of the strata, and could not be correctly taken as indicating 
an insignificant pressure. 
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