TRANSACTIONS OF SECTION C. 377 
it is bounded by low-lying plains (Kainozoie strata), which gradually broaden 
towards the west until they merge into one another. To the south Wilson’s 
Promontory (granite), South Gippsland (Mesozoic), and the Cape Otway district 
(Mesozoic) rise above the plains. The highland area is essentially a dissected 
peneplain sinking from some 5,000 feet above sea level in Gippsland to 900 feet 
at its western extremity; the only Kainozoic rocks upon it are river-gravels, 
lake-deposits, and volcanics. | 
The plains (500 feet) are areas of Kainozoic sedimentation with some inter- 
bedded and overlying volcanic rocks; the sedimentary series consists of 
lacustrine or estuarine beds, followed by marine clays (Oligocene), foraminiferal 
limestones (Miocene), and sandstones (Pliocene). These beds rest upon 
Paleozoic or Mesozoic rocks. 
On the surface of the ancient peneplain, 5,000 feet above sea level, (?) Miocene 
plant-remains and river-gravels are preserved beneath basalt at Dargo High 
Plains. This indicates a long pre-Miocene period of quiescence followed by a 
great uplift. This area has not been submerged during the Kainozoic. 
The nature of the Kainozoic series indicates that, outside the highland area, 
a gradual subsidence of considerable magnitude (Oligocene and Miocene), accom- 
panied by volcanic outbreaks (Miocene), was followed by re-elevation to a 
maximum of about 900 feet above sea level (Pliocene or post-Pliocene). There 
is evidence to show that the movements were not uniform in direction, though 
the net result was depression or elevation. Bass Strait is a recently sunken 
area in which equilibrium has not yet been established. 
The nearly horizontal position of the Kainozoic rocks indicates that the move- 
ments were vertical; and there are, moreover, examples of Kainozoic faults in 
which the differential movement amounts to 900 feet. 
The volcanic rocks are basaltic except for sporadic occurrences of alkali 
rocks in Kastern, Central, and Western Victoria. 
The Older Basalts are most abundant to the east of Melbourne. Some 
remnants occur on the ancient peneplain 3,000 feet above the present streams, 
but the most extensive areas are at lower levels in South Gippsland. At Flinders 
the Older Basalt underlies marine Miocene, and has been proved by boring to 
be over 1,300 feet thick, and to extend from sea level to that depth. In some 
instances the age can be conclusively proved, but in others the evidence is poor. 
These basalts are associated with the first great period of earth movements. 
The Newer Basalts are most extensively developed in the western district, 
where their northern boundary is not far from the 500 feet contour; here they 
overlie marine Kainozoics. Large areas are also found on the plateau west of 
Kilmore and along its northern flanks. The Newer Basalts are never covered 
by marine deposits, except recent accumulations near the coast, their surface 
is little denuded, and many of the cones of loose scoria are almost perfect. 
It appears that the Newer Basalts mark the close of the last great movement 
which elevated the marine Kainozoics. 
In New South Wales and South Australia earth movements on a grand scale 
took place during the Kainozoic period, yet volcanic action was comparatively 
insignificant. : 
7. The Tertiary Brown Coal-beds of Victoria. 
By H. Herman, B.C.H., M.M.E., F.G.S. 
The brown coal-beds of Victoria are probably the thickest yet recorded in 
the world. The more extensive areas are the La Trobe Valley, Alberton, 
Altona, and Lal Lal. Minor beds are widely distributed. 
The geological age has not yet been definitely fixed, except at Altona, where 
a brown coal-seam 140 feet thick underlies marine Oligocene beds. Flows of 
basalt overlie the brown coal in places, and underlie it in others. The range in 
age is probably from Oligocene upwards. Seams outcrop at Narracan, Thorp- 
dale, Dean’s March, Morwell, and Boolarra. 
Where below the surface the seams are prospected by boring. In many bores 
coal of several hundred feet in thickness is shown; one bore had an aggregate 
thickness of 781 feet of coal in a depth of 1,010 feet. The overburden is from 
a few feet to 500 feet deep. 
