The Geology and Physiography of tbk VVongong-Cardup Auea. 
265 
19 -THE GEOLOGY AND PHYSIOGEAPHY OF THE 
WONGONG-CARDUP AREA 
By 
Brendan P. Thomson, B.Se. (Hons.). 
Read 10th June, 1911; Pul)lisibed 5th October, 1942. 
CONTENTS. 
I. Introdnction ... 
11. Physiography : 
A. General Relief 
B. Drainage 
III. Structural Geology and Field Distribution of the Rocks ; 
A. Granite and Gneiss ... 
B. Cardup Series 
C. Basic Intrusives 
D. Later Rocks ... 
Page 
265 
266 
266 
268 
269 
270 
270 
IV. Petrography : 
A. Aplogranites, Gneisses and associated Basic Xenoliths 
B. Cardup Series 
C. Basic Intrusives of Post-Cardup Age 
D. Quartz Veins and Barite ... 
E. tjater Rocks ... 
271 
274 
275 
276 
278 
V. Conclusions : 
A. Age of the Cardup Scries and its relation to the Granitic Rocks 279 
B. Darling Scarp 279 
G. Comparison of the Wongong-Cardup, Armadale and Gosnells Areas 280 
VI. Geological History of the Area ... ... ... ... ... ... 281 
VII. Acknowledgments 282 
VIII. List of References ... ... ... ... ... ... ... ... 282 
I. INTRODrCTION. 
The Wongong'-Cardup area lies about 20 miles south-south-east of 
Perth. It extends for four and a half miles along the Darling Scarp, -which 
forms the west(>rn edge of the Darling Peneplain (Jutson, 1934, p. 81), 
from Cardup I>rook in the south, to half a mile north ol‘ Wongong Brook 
and it eovc'rs about six square miles. 
The rocks, bounded on the west by the sediment '.ry Cardup series, 
<onsist mainly of granites and g'lieisses of tin' Pre-Cambrian Darling Com- 
plex (Clarke, 1938, p. 21). These roeks are all intnided by later green- 
stone dykes. The geology gcmerally is similar to that of the Armadale area 
(Prider, lf)41). The examination of the art‘n was coiuhuded to deterraiiie 
whether the f(‘atnres of this small elos('ly mapp(‘d Armadale area were 
maintained to (he south, and to obtain further data regarding the extent 
of the CarduD series and its relation to the granitic rocks. Good exposures 
of the Cardup sediments have been made at Byford and Cardup where the 
slates are (piarried for the manufacture of pressed bricks. 
.1 m)/A'2 
