Page:Great Neapolitan Earthquake of 1857.djvu/245

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BRECCIAS AND CONGLOMERATES.
195

enter into their composition. One of the most beautiful examples is furnished by certain conchiliferous breccia, in the vicinity of Cosenza, with fragments of granite, and a great quantity of mica, which at first sight one might say was formed of granite, and which might lead the unskilful to think that they had found granite filled with marine shells like sedimentary rocks. The limestone of this series, whether tufaceous or compact, is more abundant beneath, or in the more ancient deposit; whilst the argils and sands usually occupy the upper position whenever they are found with the limestone. As to the conglomerate of large pebbles, it may be considered the most recent sub-Apennine deposit, as it is never found beneath any other kind of neptunian rock of this series. It is frequently found lying on rocks of the preceding series; the conglomerate on which Ripacandida is built, and that on which the city of Lavello is founded, furnish us with examples in the vicinity of the Vulture; the latter deposit of conglomerate extends level for many miles, from the tavern of Rendina, to the northern district of the territory of Lavello. The southern declivities of the Vulture which are included in the name Monticchio, are formed of deep deposits of the same conglomerate, which will by-and-by claim our attention. The cities of Venosa and Carbonara are also built on extensive deposits of large pebble conglomerate, the arrangement of which differs so much from that of the preceding instances, because it lies on conchiliferous sub-Apennine marl, which is distinctly visible near La Fontana de' trenta Angeli, little more than two miles N.N.E. of Venosa. The immense quantity of pebbles which are frequently found heaped together in the heart of our Apennines is an evident proof of the great diluvial action to which these regions were subjected after the deposition of the supercretaceous rocks. Abandoning the inquiry into the unknown cause of this catastrophe, we may, with better hope of success, seek to discover whether it preceded the emergence of Southern Italy from the sea, or whether it was subsequent to it. Of these opinions, the second is perhaps the more likely to be true, as no marine fossils have ever been found in the conglomerate of which we have spoken; and although we have never been so fortunate as to meet with any land animal remains, yet in the Mineralogical Museum

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