The Geology and Physiography of the Gosnells Area. 245 
18 .-THE GEOLOGY AND PHYSIOGEAPHY OP THE 
GOSNELLS AREA 
By 
C. E. S. Davis, B.Sc. (Hons.). 
Read 10th June, 1941; Published 2nd October, 1942. 
CONTENTS. 
I. Introduction ... 
II. Physiography : 
A. General Features 
B. Darling Scarp 
C. Streams 
D. Remnants of the Peneplain 
E. Effect of Geology on Topography 
F. Springs 
III. Structure and Distribution of the Rocks : 
A. Xenoliths 
B. Granite 
C. Acid Intrusives into Granite 
1). Cardup Series 
E. Basic Dykes ... 
F. Edge of the Pre-Cambrian Rocks 
G. Laterite : 
(1) High Level 
(2) Low Level 
H. Later Superficial Deposits ... 
IV. Petrology : 
A. Xenoliths 
B. Granite 
C. Acid Intrusives : 
(1) Pegmatite and Aplite 
(2) Quartz Masses 
D. Cardup Series ; 
(1) Arkose and Slate 
(2) Sandstone 
(3) Metamorphism 
E. Basic Intrusives ; 
(1) Uralitised Quartz Dolerite (Epidiorite) 
(2) Biotite Epidiorite 
(3) Biotite-Epidote Veins 
(4) Porphyritic Epidiorite 
V. Geological History ... 
VI. Acknowledgments 
VII. Bibliography ... 
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1. INTRODUCTION. 
The Gosnells Area lies 15 miles south-east from Perth, on the long, 
straight Darling Scarp which separates the loAV-lying plain (on which Pertli 
stands) from the level Darling plateau whose surface is about 1,000 feet 
above sea level. The Darling Scarp here forms the western boundary of 
the Pre-Cambrian rocks which outcrop over so much of Western Australia, 
j 331/42 
