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Symposium on Remote Sensing for Resources Development and Environmental Management / Enschede / August 1986 
An evaluation of potential uranium deposit area by Landsat data 
analysis in Officer basin, South-Western part of Australia 
H.Wada & K.Koide 
Power Reactor and Nuclear Fuel Development Corporation, Tokyo, Japan 
Y.Maruyama & M.Nasu 
Asia Air Survey Co. Ltd, Tokyo, Japan 
ABSTRACT: An evaluation of potential uranium deposition area was carried out by the Landsat MSS data analysis. 
As a denominator land coverage, depth of basement rock and density of vegetation are chosen. The area well 
evaluated in Officer basin area lie on the mining or the prospecting area at present time. 
1 INTRODUCTION 
Economic uranium mine is identified into some typical 
type by geological condition, (1) sedimentary deposit 
(2) related with unconformity (3) hydro thermal type 
(4) volcanic origin, etc. The purpouse of this study 
is to evaluate the possible area of sedimentarty ura 
nium deposit with using Landsat imagery. 
In general, the ultimate sources of uranium are 
granite, granitic detritus, and silicic volcanic ash 
and flows. Uranium was leached from the source rocks 
and transported in solution by oxygen-rich ground 
water and then migrated into porous sandstone or con 
glomerate beds. Within these eventual host rocks the 
migrating water encountered reducing conditions caus 
ed by the presence of organic material, natural gas 
or hydrogen sulfide,etc. The environment of chemical 
change from oxidizing to reducing caused the uranium 
to precipitate as oxide minerals, primarily uraninite, 
which coat sand grains and fill pore spaces in the 
host rock. According to these processes of develop 
ment the environment of uranium deposition can be 
estimated to have following conditions. 
A. The area is surrounded by the mountains composed 
of the ultimate source of uranium such as granitic 
rocks. 
B. The depositional condition 
(1) The area of sedimentary rocks distribution is 
extensive. 
(2) The thickness of sedimentary rocks is high 
(possiblity of ground water). 
(3) Existing the high porocity in the bed (host 
rock). 
(4) Succesion of high porocity zone (paleo chan 
nel) . 
(5) The reducing agent : organic material or natu 
ral gas in the host rocks. 
The sedimentary uranium deposit can be realized 
under two conditions, one is the area suppling urani 
um to oxdized ground water and the other is the re 
ducing zone to precipitate it in the sedimentary 
rocks. 
All of the condition for uranium deposition, which 
mentioned above is not possible to be analysed only 
by Landsat imagery. Thus, the some of those condi 
tion for uranium deposition are analysed by Landsat 
MSS data in this paper. And evaluation of the possi 
ble area was taken place from the view points of the 
thickness and extent of sediments and succession of 
high porocity zone (paleo channel). 
2 AREA STUDIED 
2.1 Location 
The area studied is located in the southern part of 
Officer basin, South-east Australia. There is among 
Figure 1. Location of studied area 
Long. 122°30’ - 125°00' E and Lat. 28°00' ~31°00' N 
(Fig. 1). 
2.2 Topography and climate 
It is on the south-western part of Great victoria 
desert. The basin generally is flat or gently undu 
lated, of which is mainly sand dune. 
Climatic condition is arid ~ semi arid. As annual 
amount of presipitation is l80 ~ 200 mm and evapora 
tion is more than 2000 mm, the river is dried up in 
the most of year. 
Average temperature is 30 ~ 35°C in summer and is 
18°C in winter. Area is covered by barren vegetation 
such as spiniphex, marry, marblegum, etc. 
2.3 Geology 
Geological structure of West Australia is composed 
of pre-Cambrian western shield and some of the sedi 
mentary basin on it. 
Officer basin extending on the eastern margin of 
Yilgam block is composed of granitic and metamorphic 
rock. Sedimentation was taken place during lower Pa 
leozoic to Tertiary under the neritic and continental 
environment. Lower part of sedimentary rocks is 
called Patterson formation which is clay dominant 
Permian system. This formation was eroded to make 
the continuous valley in it. Sedimentation in Creta 
ceous and Tertiary covered these valley unconformably. 
They are composed of conglomerates, sandstone, silt 
and clay.