Bryan, W. H. (Walter Heywood)

University of Queensland eSpace

University of Qyeensland 
PA PERS 
D E PA RT M E N T  OF GEOLOGY 
Volume 1 (New Series) 1938 Numbers 5 and 6 
5. The Establishment of a Seismological Station in 
Brisbane, Queensland 
BY 
W. H. BRYAN, M.C., D.Sc. 
6. The Gayndah Earthquake of 1 935 
BY 
W. H. BRYAN, M.C. , D. Sc. , and F. W. WHITEHOUSE, Ph. D. , M.Sc. 
REPRINTED 
from 
THE PROCEEDINGS OF THE ROYAL SOCIETY OF QUEENSLAND 
VOJ .. XUX, Noa. 9 aad 10, pp. 104-105 and 1 06-1 19 
JUNE, 1938 
THE E STABLISHMENT OF A SEI SMOLOGICAL 
S TATION I N  BRI SBANE, QUEENSLAND. 
By 
W. H. BRYAN, D.Sc. 
Geology Department, Uni'versity of Q ueensland. 
[Reprinted from the Proceedings of tke Royal Society of Qu,ee nsland, 
Vol. XLIX., No. 9, pp. 104-105. ] 
DAVID WHYTE, Governl!:ent Printer, B1·isbane. 
104 VoL. XLIX., No. 9 .  
The Esta brisll ,ment  of a Seismological St at io 11 w B risbane, 
Queensland. 
BY W. H. BRYAN, D.Sc. 
Geology Department, l "  niversity of Queensland. 
[ R.ead before the Royal Societ�· of Queensland,  �5th October, 193 7 . ]  
D DRING the past there has existed very little local interest in  seis-
mology. This lack of enthusiasm for a science that elsewhere has 
many ardent stU\dents is almost certainly due to the fact that perceptible 
earthquakes are of raz·e occurrence in Queensland. Thus since the 
-establishment of the University of Queensland twenty-seven years ago 
there have been only two noteworthy earthquakes within the State. The 
first of these occurred in 1918, and was investigated by Hedley1 some 
years later. The second, which took place on 12th April, 1935, and 
which has been described b�· Bryan and Whitehouse,2 vvas of sufficient 
intensity to arouse considerable popular interest. In a statement made 
in the public press at this time, the writer deplored the fact that there 
was no seismograph in operation within the State and urged the neces­
sity of establishing a seismological station in this part of Australia. 
Following this appeal a gentleman who wishes to remain anonymous, 
but who was an early student at the University of Qu eensland, gener­
ously offered to provide the money necessary to purchase a Milne-Shaw 
Seismograph ( No. 58) . 
Subsequent to the acceptance of this generous offer the Council for 
Scientific and Industrial Research was approached with the request that 
a second similar 1\-iilne-Shaw instrument be obtained in order to make 
the proposed station of greater value and more self-contained. This 
request was favourably received and a second instrument (No.  60 ) thus 
secured. 
THE SITE.* 
The temporary site selected for the station in which these instru­
ments are housed is in the basement of the new University Library. 
This position has many things to recommend it, the principal being its 
convenience, for it is closely adjacent to the Department of Geology, 
from which the station is controlled. The chief adverse factors are the 
absence of solid rock tnl' which to base the foundations ( the Library 
building having been erected on a relatively unconsolidated river terrace 
alluvium ) ,  and the nearness to the city. But since many excellent 
stations are successfully operating under somewhat similar conditions 
these objections were not thought sufficiently strong to warrant the 
selection of a less co�venient site. , . 
The most suitable part of the basement having been selected, it 
was bricked off to form a light-proof and draught-proof room with a. , 
reasonably equable temperature. 
The exact position of the site was carefully :fixed by Mr. F. James. 
M.Sc., Lecturer in Surveying at the University of Queensland, as 
L atitude 27 ° 28' 41" S. ,  Longitude 153° 1' 52" E . ,  Elevation 15 metres. 
Mr. James was also responsible for fixing the direction of tbP 
meridian within the seismograph cellar. 
1 Trans. R.oy. Geog. Soc. Qld. Vol. 1, p. 151, 1925. 
2 Proc . R.oy. Soc. Qld. Vol. 49, pp. 106-119. 
* The permanent site of the station will be within the University of Queensland 
grounds at St. Lucia, where eminently suitabl13 conditions should be found when 
the University is finally established there. 
ESTABLISHMENT OF A SEISMOLOGICAL STATION IN BRISBANE. 105 
THE FOUNDATIONS. 
The two instruments are set up on a single foundation designed bv 
the writer in co-operation with Mr. N. L. Thomas, of the Governmenr. 
Architect 's Department. 
The foundation consists of a solid monolith of concrete weighin� 
approximately 9i tons. It is not reinforced in any way, and the 
concrete was poured as one continuous operation. The foundation is 
L-sharped, one side of the L being carefully aligned on the meridian 
and the other side at right angles to this. The whole concrete monolith 
is sunk 2 feet into the earth, is independent of and free from the 
foundations of the building, and is separated from the concrete floor of 
the cellar by a dry moat 5 inches wide and 8 inches deep . 
THE SEISMOGRAPHS. 
The instruments consist of a pair of Milne-Shaw horizontal pendulum 
seismographs with electro-magnetic damping. Each instrument has been 
adjusted to a period of 12 seconds, a damping ratio of twenty to one, 
and a magnification of 250. 
Of the instruments as set up No. 58 registers the north-south 
component and No. 60 the east-west component. 
The recording system is an optical one, the record being received 
on special Bromide B paper secured to a drum which is operated by a 
-clockwork mechanism. 
THE TIMING ARRANGEMENTS. 
The time signals appearing on the ·record are controlled by a 
synchronome clock with half-minute impulses, alternate pulses of which 
are selected by another synchronome mechanism to give minute breaks 
on the record, each with a duration of 3 seconds. The hour is recorded 
as the first of three half-minute signals. The daily error in the station 
time is determined by comparing it by means of a radio receiving set 
with Eastern Australian Standard Time as broadcast by Station 4QG. 
Corrected times are finally converted to Greenwich Mean Time for 
purposes of record. 
CONCLUSION. 
The trials already conducted have on the whole been most satis­
factory. Local disturbances obtrude themselves only when heavy 
hammering is being done on the floors and walls of the still incomplete 
building that houses the station. On the other hand, those records of 
earthquakes that have been recorded are . very satisfactory on account 
-of their clarity, and more particularly in the ease with which the initial 
impulse of the preliminary waves can be marked off from the microseisms. 
The station is in touch with other earthquake observatories in 
Australasia and elsewhere, both directly and indirectly, through the 
Seismological Research Committee of the Australian and New Zealand 
Association for the Advancement of Science. 
Situated as it is on the margin of the actively seismic Pacific basin, 
this new observatory should play an important part in international 
seismology, more particularly as it helps to bridge the large gap in the 
chain of circum-Pacific stations that hitherto has existed between Sydney 
and Java. 


The establishment of a Seismological Station in Brisbane, Queensland

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The establishment of a Seismological Station in Brisbane, Queensland

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