Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/418

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" From Moonlight Head to the mouth of the Gellibrand river a very peculiar suite of beds occur. The fossils they contain are evidently Miocene ; but, with the exception of being very similar in composition to the leaf-bed occurring between the Aire river and Castle Cove, and also to the beds composing the cliffs about a mile east of Point Addis, they appear to have no equivalents on any other portion of the coast. About a quarter of a mile east of the mouth of the Gellibrand, these beds terminate abruptly, with Pliocene Tertiary resting on and against them. From this point they gradually rise to the eastward, at an angle of about 10°, for about two and a half miles, when they rest horizontally, or nearly so, on the Mesozoic sandstones ; thence they continue, with slight undulations, along the coast to the east. The following section, shown in the cliffs from near the Gellibrand river for about two and a half miles eastward, will, I think, give approximately the thickness of these beds.

" Commencing at sea-level we have : — (1st) 45 feet greyish-brown Carbonaceous sandstone, showing false bedding, and containing hard concretionary nodules and fragments of carbonized wood ; (2nd) 50 feet of thin ferruginous sandy beds, with small rounded quartz pebbles, the uppermost beds containing fossils, principally Cuculloea, Cytherea, and Nautilus, labelled No. 6; (3rd) 125 feet of nearly black argillaceous beds, containing a few rounded quartz pebbles sparingly interspersed. Crevices in these beds contain the same yellow basic sulphate of iron previously mentioned. In the middle portion of these beds a few fossils are found, chiefly a species of Petraia, numbers of a small Turritella, aggregated in patches, and a few sharks' teeth, labelled No. 7. [The Petraia above mentioned is Trochocyathus meridionalis, Duncan, which is accompanied by Trochocyathus Victorioe and Cycloseris tenuis, Duncan.] These fossils occur chiefly in a very hard stratum, the hardness of which alone distinguishes it from the softer beds of similar colour with which it is interstratified. (4th) 35 feet of yellow and red ferruginous sandy strata without fossils ; (5th) 40 feet of black beds similar to those just described, with the exception that they apparently contain no fossil shells ; but wherever you examine them, numerous small branching markings, like Algae, are found. Specimens obtained, labelled No. 8. The same is observed in all the black beds of this section ; also in those between the Aire river and Castle Cove, and in the strata before referred to, about a mile east of Point Addis. Above this we get white, yellow, and red sandy clay, passing up into rounded quartz-pebble drift, probably Pliocene, together about 50 feet. Total thickness from (1st) to (5th) inclusive, about 250 feet. "West of the Gellibrand the miocene strata are of an entirely different character, and occupy a very wide area. They occur in the cliffs along the coast for nearly forty miles, and extend north nearly to Camperdown, where they pass under the basalt. For thirty chains from the mouth of the Gellibrand the cliffs are entirely composed of Postpliocene tertiary sandstone ; the Miocene beds dipping to the east then commence. A section ten chains further along the coast gives, above sea-level : —