OO W. G. WOOLNOUGH. 



The views of the last two authors are merely of the nature 

 of suggestions as neither has had the opportunity of examin- 

 ing the area personally. 



Jutson and Simpson 1 have called the Tertiary Marine 

 Beds of Albany, the "Plantagenet Series." These beds 

 are recognizable in the area under consideration and occur 

 abundantly on the Kalgan River. Patches of them can be 

 seen right up to the foot of the Stirling Range itself. 



Geology of the Stirling Ranges (Lithology). 

 Geologically the mountains are of extreme interest and 

 importance. The great bulk of the south-western portion 

 of Western Australia is composed of crystalline rocks; 

 granites in great variety, gneiss, greenstone, (including 

 chiefly quartz-doierite and epidiorite), and acid and basic 

 crystalline schists. Comparatively few areas of unaltered 

 or little altered sediments occur. 



The mountains are built up of a series of undoubted 

 sediments amongst which quartzite and slaty shale pre- 

 dominate. No limestones are known and conglomerates 

 are extremely rare. The base of the formation is nowhere 

 exposed, the contacts with the crystalline formation being 

 either igneous or faulted. For the most part the sediments 

 lie in horizontal or very gently dipping layers, but, locally, 

 steep dips are exhibited and sharp folds and overfolds are 

 not wanting. Evidence will be adduced to indicate that 

 heavy normal faulting and subordinate overthrusting have 

 occurred. The portion of the formation which is exposed 

 is certainly not less than 3000 feet. 



The quartzites and slates alternate very regularly through- 

 out the entire series, though there is a slight preponderance 

 of the former at lower levels and of the latter at higher 



1 Jutson, J. T. and Simpson, E. S. — Notes on the geology and physio- 

 graphy of Albany. Proc. Roy. Soc. W. A., Vol. n, 1915-16, pp. 45- 58. 



