Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/414

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very late in the time when the extinct antetypes of the existing Australian mammalian fauna nourished.

The basalt immediately above the coralline limestone limits superiorly the marine fossiliferous series. Its equivalents in time were, in all probability, the clay, the ferruginous sandstones, and the sandy limestones which cover the so-called Miocene to the north- west of the Glenelg ; and these beds, which are well-developed on high ground, form the upper gold-drifts.

A great upheaval, probably affecting the whole of Central Australia, occurred after this outburst, and determined the present configuration of the land, which has suffered from no glacial conditions, but from great denudations of all kinds, the encroachment of sand, the formation of salt lakes, and repeated volcanic outbursts. It is evident that a vast basaltic layer covers the fossiliferous beds, the drift upon them, and the old rocks where they are not covered by those tertiaries to which the names of Miocene and Pliocene have been given.

The section at Spring Creek, by Mr. Daintree, exhibits the succession of beds in the marine fossiliferous tertiaries as follows : —

( Upper Miocene.) feet.

Hard thin-bedded sandy limestone, the calcareous portion consisting almost entirely of corals 80

(Middle Miocene.)

Soft, brown, sandy clay 80

Brown, blue, and yellow sandy clays 30

Very hard crystalline sandstone 1

Brown sandy clay poor in gypsum 12

Very hard crystalline sandstone 1

Brown sandstone containing abundance of gypsum 5

Blue marl containing septaria, gypsum, and iron-pyrites 10

Friable thin sandstone with thin bands of gypsum 8

(Lower Miocene.)

Very hard crystalline sandstone 1

Soft brown sandstone with thin bands of harder material 4

Soft brown sandstone 13

Thin-bedded brown sandstone 20

Blue and grey friable sandstone 8

273

M'Coy and Selwyn have used the European nomenclature ; but I prefer to term the series Cainozoic ; and as it appears to me that the upper member of the fossiliferous series is merely a deep-sea deposit (in a general sense) and contemporaneous with those below it, I cannot see the propriety of terming it Pliocene. The term Cainozoic is infinitely preferable here.

Nor can I distinguish between the fossiliferous series and the sands, clays, and ferruginous beds above it, except in admitting the