the Alps and Apennines in Liguria. 407 
and all the other formations of the district. The gneisses and 
amphibolites he regarded as primitive and the granite as intrusive in, 
and therefore more recent than, the same. The superposition of the 
gneiss on the Permo-Carboniferous near Quiliano in the south-west 
corner of the area is, in his view, due to an inverted fold (rovescia- 
mento), the normal sequence of gneiss and Verrucano appearing 
further north, near Altare. He regards the Savona crystalline massif 
as forming part of the inner Alpine belt of massifs from Monte Rosa 
to the Grajan, Eastern Cottian, and Maritime Alps, and the Savona 
eneisses as akin to those of Gran Paradiso and La Levanna (Grajan 
Alps) rather than to those of Mont Blanc. 
2. Under a novel aspect the problem was presented in an important 
memoir with maps and sections by Rovereto in 1909.’ His pains- 
taking survey of both the crystalline and sedimentary formations of 
the area led him to the conclusion that the reversed, anomalous 
sequence of the gneiss and the Permo-Carboniferous series is best 
explained by a local and partial overthrust or displacement of gneissic 
and granitic rocks from the eastern to the western part of the area. 
This conclusion he bases on the following grounds :— 
(1) That the Permo-Carboniferous island between Savona and 
Santuario presents all the characteristic features of a ‘window’ 
which discloses that formation as the substratum, here assumed to 
form an anticline. 
(2) That in the south-western part of the massif the gneiss mass to 
which the Permo-Carboniferous strata are adjacent on either side 
rests against the latter obliquely in opposite directions, and is there- 
fore fan-shaped, whereas the gneiss mass north-east of the Santuario 
_island is essentially isoclinal. 
(3) That in that island the eastern contact line of the Permo- 
Carboniferous schists and the gneiss is comparatively normal and 
undisturbed, whilst the western contact line exhibits marked 
. unconformity, contortions, and brecciation. 
Hence the inference that the eastern part of the crystalline massif 
is a ‘‘rooted’’ and the western part a ‘‘transported”’ area, viz. a 
cover-sheet by displacement.? The gneisses and amphibolice rocks of 
the massif are, according to Rovereto, Pre-Carboniferous, and the 
granite erupted in the Upper Paleozoic.* 
38. A much bolder and sweeping interpretation of the Savona 
massif is that of Termier and Boussac in their brilliant memoir of 
1 G. Rovereto, ‘‘ Zona dei Ricoprimenti del Savonese’’: Boll. Soc. geol. It., 
1909, p. 389 et seq. This memoir was preceded by two preliminary notes on 
the same subject in 1895. 
2 This fan-structure, shown in general section Fig. 2, rests on the 
assumption that the adjoining Permo-Carboniferous island on the right is an 
anticline, not a syncline. 
3 Besides this solution Rovereto adumbrates three others, which, however, 
he considers less tangible: the first assumes the whole massif to be a rooted, 
the second a transported area, and the third assumes not only the Savona area 
but the whole of the Apennines to be a series of transported cover-sheets. 
4 Franchi (op. cit., p. 64) refers to the granite as being on the eastern border 
intrusive also in the cale-schists and pietre verdi; these being Mesozoic, the 
granite would be much younger than Upper Paleozoic. 
