
644 RECORDS OF THE S.A. MuseuM 
of the continental shelf seem to indicate by their directions, that the systematic 
diversions of stream channels may have been continued far out on to the shelf 
during periods of lowered sea level, 
During the whole period while Reedy Creck mouth was moving northward 
40 miles between the Tlundred of Kennion (inland from ITlatherleigh) and 
Blackford, Brown Cattle Creek seems to have maintained its mouth in a relatively 
fixed position, Its meanderin® channel through the ‘‘range’’? shows a rather 
mature valley with a terrace which runs ont into the air on the foreshore of 
Reedy Terrace. Deepening of the channel in Post-Reedy times has. been limited 
by the granitic stveam bottom over which it flows, 
Data on the headwaters of Reedy and Brown Cattle Creeks is not yet fully 
marshalled. Traeed inland these two waterways between them seem to have 
links with most of the streams coming off the old land surface to the east. 
However, the greater part of the drainage west of Naracoorte and Penola is now 
subterraneously established and it is difficult to be sure of some of the former 
connections. 
West of Naracoorte several streams flow out into lagoons and lakes. In 
understanding the formation of these lakes (e.g, Lake Roy, Bool Lagoon and 
Carey Swamp) an important factor which must not be overlooked is that of the 
level of the water table. This is always the base level of the cycle of karst drainage 
development, Thus during periods of low sea level there was an activation of the 
underground drainage proeesses and at the same time an increase of relief, In 
periods of rising sea level, the dramage basins became drowned and appeared as 
lakes. On the general thesis of a Post-glacial rise of sea level the latest, bistory of 
these drainage basins is one of lake Formation and growth concurrently with the 
Tise In watertable, 
EVIDENCE FOR SUBMERGED TERRACES OFF THE COAST OF THE 
SOUTH EAST OF SOUTIT AUSTRALIA. 
Admiralty chart, No, 1,014, Cape Jervis to Rivoli Bay, shows the continental 
shelf of the South East of South Australia with bathymetric data only sufficient 
to hint at locations and numbers of possible submerged terraces upon its slope. 
It seems clear that such low level terraces have existed, for there are indications 
that at different times during the history of Reedy Creek it has oceupied different 
river channels extending across the continental shelf, for example, south of Cape 
Buffon out from Lacepede Bay, out from Coalatoo and ont from Chinaman Well. 
Since the approximate times at which each of these different channels was in use can 
be determined, evidence of the limits to which each successive channel ean be 
traced on the continental shelf might be expected to indicate the order of suecession 
of low level terraces, 
