RECENT SUBMERGENCE OF COAST AT NARRABEEN. 229 
EVIDENCE OF RECENT SUBMHRGENCEH or COAST 
AT NARRABEEN. 
By T. W. EpGEWoRH DAVID, B.A., F.R.S., Professor of 
Geology, University of Sydney, and GERALD H. 
HALLIGAN, F.G.S., Hydrographic Officer, Public 
Works Department. 
[With Plates XXXVIII., XXXIX.] 
[Read before the Royal Society of N. S. Wales, September 2, 1908. ] 
I. Introduction.—IN view of the general physical features 
of the coast line of New South Wales for some distance to 
the north and south of Sydney, as well as of evidence 
supplied by bores and shafts in the neighbourhood of our 
coastal areas, it seems clear that one of the most recent 
movements of the coast line had been a negative one, that 
is sea level had risen in relation to the land. To state it 
otherwise, there had been recently a positive movement 
of the ocean. 
In a paper contributed to the Royal Society of New 
South Wales by Messrs. R. Etheridge, J. W. Grimshaw, 
and T. W. H. David,’ a description was given of a submerged 
forest at Shea’s Creek, near where Cook’s River enters 
Botany Bay. The trees of this submerged forest grew at 
a depth of 15 feet below high water, being in position of 
growth with numerous roots extending out over 12 to 15 
feet from the parent stem. The trees all belong to species 
which are now found in the immediate neighbourhood. In 
places the old forest was found to pass into a bed of peat. 
Three aboriginal tomahawks were discovered in association 
* R. Etheridge, T. W. E. David and J. W. Grimshaw, On the Occur- 
rence of a Submerged Forest with the Remains of a Dugong, at Shea’s 
Creek, Sydney, this Journal, xxx, 1896, pp. 158 - 185, pl. viii. — x1. 
