Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/641

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On the Succession of the Upper Triassic, Rhaetic, and Older LiASSic Deposits near Hommona in North Hungary. By M. Paul.

[Proc. Imp. Geol. Institute, Vienna, 31st July, 1869.]

The succession of these deposits in descending order is as follows : —

White- veined Limestones, occasionally dolomitic, constantly associated with layers of quartz.

Grey Marly Shales, alternating with compact Limestone -beds, containing Pentacrinites, Lima (?), and other indistinct organic remains (24-28 feet).

Limestone with Plicatula intus-striata, Ostrea Haidingeriana, Pecten, &c. (6-12 feet).

Limestone, with large Megalodon sections (3-4 feet).

Limestone, with Terebratula gregaria (6-12 feet).

Dolomitic Marl (3 feet).

Limestone, with Lithodendra (9 feet).

Limestone, with abundance of Terebratula gregaria, which is associated in the deeper nodular layers with Cephalopods and Gasteropods (24—30 feet).

Marly Limestones, with Plicatula intus-striata, Ostrea Haidingeriana and Pecten (6 feet).

Soft dark Shales (3 feet).

Dolomitic Marls, more compact (3 feet).

Soft Marls, alternating with more compact beds (3 feet) .

Dark red, very crumbly Marl-shales (12-18 feet).

Quartzite and coarse Quartz-sandstone, very like that occurring in the Lias (30-36 feet).

Dark Shales, with distinct, compact beds, which are sometimes quartzitoid (36-48 feet).

Variegated Marls in thin layers, somewhat dolomitic (120-180 feet).

? Dolomitic Breccia.

The white-veined Limestones are overlain by Dolomites containing Belemnites, and these by Limestones with hornstone and traces of Crinoidal Limestone, which may represent the superior Jurassic deposits.

This section proves that the white-veined Limestone, so widely spread in the Carpathians, and generally referred to the Trias, belongs, with its subordinate Dolomites and Quartzite-beds, to the Lias. It is not, however, the lowest stage of that formation, as is proved by the Quartzites of the Little Carpathians, between which and the Kossen beds a great deposit of dark-coloured Limestone is intercalated. This section reveals another fact of interest with regard to the Kossen beds, namely, that Bivalves and Brachiopods may alternately predominate repeatedly, so that they do not stand to each other in the relation of constant stratigraphical horizons. [Count M.]