Page:Great Neapolitan Earthquake of 1857.djvu/415

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of crumbly limestone rock have taken place, from both its faces, but chiefly from that on the south side, where the detached masses have fallen from the ends of nearly vertical ill-defined beds, whose strike is N. W. and S. E. This, like every case of fallen rock that I have so far observed, has been detached from a vertical or nearly vertical bed, where, owing either to the joints of the beds themselves or to cross fissures, there was little or no adherent connection with the adjacent rock; in fact, cases of loss of equilibrium and fall by inertia, and not of rending asunder through the solid stone, and dislocation by the direct energy of the shock.

Upon the opposite or west flank of the Vallone, and further south, stands Diano, the town from which it takes its name, upon a low, stumpy, jutting-out spur, of soft limestone, to the eastward of the great range (see Photog. page 165, No. 108, Part I).

The main direction of this spur, is nearly due north and south by compass, rising gradually from the plain at the north end; and it is completely cut off from contact with the great lateral chain of mountain, except at nearly the level of the plain, by the long lateral Vallone del Raccio, which brings in one of the great feeders to the Calore on its left bank, and whose bed in the bottom of the vallone, seems to lie in the line of a great dislocation.

This town has suffered comparatively little by the shock, many fissures, and a few of the old ill-built miserable class of houses thrown down, direction apparently north to south, none affording good data.

The beds of limestone rock at both sides of the valley, from above Atena southward to below Diano on the west,