Page:Quarterly Journal of the Geological Society of London, vol. 35.djvu/57

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GEOLOGY OF NORTH GIPPSLAND, VICTORIA.
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GEOLOGY OF NORTH GIPPSLAND, VICTORIA.

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formations similar to those I have now endeavoured to describe are met with until Mount Tambo is reached beyond Omeo.

The subjoined diagram section of the Mount-Tambo beds (fig. 11) is condensed from the sections which I have worked out to illustrate the paper I have already mentioned.

Fig. 11. — Diagram Section across the Mount-Tambo beds.

B.W. 8crubby Creek. Mount Tambo. N.E.

a. Tambo beds.

b. Bindi Limestone.

c. Qnartz-porphyrie3.

Granites. Silurian.

We have here the lowest part of a synclinal fold resting uucon- formably on the Bindi Limestone, and in a basin of the " Lower Palaeozoic rock-foundation." The series commences with a thick coarse conglomerate of pebbles of quartz, indurated slates, and other siliceous rocks, and extends upwards, through sandstones, grits, and red rubbly shales, to another thick bed of somewhat similar but less coarse conglomerate. From this point the mountain slopes rapidly into lower country. All these beds to the second conglo- merate thin out to the southward, and are entirely wanting in Bindi.

The remainder of the series gradually becomes finer in character until the uppermost beds are all rather fine sandstones and slaty shales.

Conglomerates show again at the next margin of the basin, and I regard these as being the probable equivalents of the second con- glomerate. Shortly following that conglomerate I have found a thick band of compact yellowish or whitish felstone, which is in places quartziferous. But I am quite unable at present to say whether it may represent the felstones of Tabberabbera, Maximilian Creek, and the Snowy Bluff, or whether it is a very large intrusive mass.

A great irregular dyke-like mass of diorite (?) is also visible in one section, but does not seem to show either to the north or south along the strike of the Tambo beds, and is doubtless intrusive.

I was unfortunately unable to find the plant-bearing shales men- tioned by Mr. A. R. C. Selwyn * ; but bearing the fact stated by him in mind, and considering the marked resemblance in the lithological character, the sequence, and stratigraphical position of the Tambo beds, their resemblance to those of Iguana Creek becomes strongly

  • Intercolonial-Exhibition Essajs, 1866, "Notes on the Physical Geogra-

phy, Geology, and Mineralogy of Victoria," p. 15.