Upper Palaeozoic Rocks . 
61 
Sketch-map, the extension of the Upper Paleozoic rocks up to 
the Main Divide, and their continuity with those of the Macalister 
country. 
On the ranges between the Jamieson and the Ilowqua, and 
between the Howqua and the Delalite Rivers, are huge masses 
of red breccia-conglomerate resting on the Silurian rocks, near the 
boundary of the Upper Palaeozoic, in the same manner as in the 
Avon country. 
The general resemblance to one another of the rocks in various 
localities throughout the eastern Upper Palaeozoic area justifies 
the general provisional reference of the whole series to the Upper 
Devonian period, which the Iguana Creek beds serve to identify. 
At Mount Tambo, on the Main Divide, occurs a large outlier, 
of Upper Paheozoic rocks, resembling, in general lithological 
character, the Avon Sandstones, and containing, according to 
Mr. Selwyn, similar plant-impressions. 
Mr. A. W. Ilowitt’s map, and his accompanying essay on the 
Devonian rocks of North Gippsland, supply the following infor* 
mat ion as to the character and mode of occurrence of this outlier. 
The foundation oil which the Mount Tambo beds rest is granite 
on the south, Upper Plutonic quartz-porphyries, &e., ou the 
south-east and west, and metamorphic crystalline schists on the 
north-east. A small vestige of the Middle Devonian limestones 
of the Hindi group also passes under the Mount Tambo beds, at 
the south-eastern margin of the latter. 
Ascending Mount Tambo from the north-eastern side, the 
first layer of the Upper Palaeozoic series, resting on the meta- 
morphic rocks, is a coarse conglomerate, without any sign of strati- 
fication, and composed of rounded fragments of quartzite, quartz, 
and indurated slates, with a few boulders and pebbles of siliceous 
quartz-conglomerate. 
This conglomerate bed becomes finer upwards, and passes into 
a coarse reddisli-ycllow grit with sub-angular fragments of quartz 
and indurated slate, overlaid by a bed of about 50 feet in thickness 
of rubbly brick-red or purplish rock, showing little sign of strati- 
fication. * On this are sandstones, about 40 feet thick, followed by 
about 120 feet of coarse to fine conglomerate ; then a second bed 
of red rubbly rock overlaid by coarse conglomerate, forming the 
summit of the mountain. The total thickness of these beds is 
nearly 1,500 feet, and their dip is south-westerly at from 37° to 
45°. Following the descending ridge south-westerly in the direc- 
tion of the dip, the last-mentioned conglomerate is followed by 
yellowish sandstone and sandy shales, with a covering of con- 
glomerate. (Fig. 23.) 
A gradual change commences from here ; the beds become finer 
and more argillaceous ; the dip becomes more vertical, and is finally 
reversed to the opposite direction, when it gradually becomes more 
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