THE 



GEOLOGICAL MAGAZINE 



NEW SERIES. DECADE VI. VOL. II. 



No. VII— JULY, 1915. 



OZRIG-IZDT.A.r, AETIOLES. 



I. — The Geological Age of the Cabeara Maebles. 



By Professor T. G. Bonney, Sc.D., F.E.S., and the Eev. H. H. Winwood, 



M.A., F.G.S. 



T I ^HE statuary marbles of Carrara have been repeatedly asserted to 

 _|_ be metamorphic limestones of earlier Mesozoic or later Palaeozoic 

 age. Similar statements were once frequent in regard to other 

 mountain regions, but they have one by one dropped out of geological 

 literature. This, however, is such a hardy perennial as to be still 

 repeated in petrological and other textbooks. 1 Doubts, however, were 

 felt by the first author in 1878, and these became almost certainties 

 after 1886, but as each visit was only for a few hours, 2 and did not 

 allow of a proper examination of the rocks in situ, he deferred 

 writing on the subject till he could spend a longer time at Carrara. 

 That opportunity, however, never came, and is not now likely to 

 occur ; but on finding not long since that his friends, Professor Boyd 

 Dawkins and the Rev. H. H. "Winwood, had visited the quarries in 

 1898, and the latter had published an account of the district, with 

 a sketch-section drawn by the former, 3 he communicated with them, 

 and the following paper summarizes the experience of the three, 

 which it is hoped may help in laying another metamorphic ghost. 4 



1 See, for example, Text-booh of Petrology, vol. ii, Sedimentary, F. H. Hatch 

 and B. H. Bastall, 1913, p. 250. In books of earlier date the marbles are said 

 to be Lower Jurassic, Building and Ornamental Stones, E. Hull, 1872, p. 127 ; 

 Triassic, TraiU de G&ologie, A. de Lapparent, 1906, p. 1100 ; Upper Triassic 

 on the Carta Geologica dellaLiguria, by A. Issel and S. Squinabol (1891), and 

 they are associated with micaceous schists in a short text published with the 

 map. They are assigned to the same age in a description of an excursion to 

 Carrara, Bollettino delta societd Geologica Italiana, vol. xxi, p. 163, 1902, 

 which classes some underlying schists and marbles as Permo-Carboniferous, 

 and some schists beneath those as indeterminate Palaeozoic, and gives the 

 following succession of the overlying beds, from the base of the Miocene 

 sandstones and conglomerates : Eocene, sandy and calcareous strata ; Upper 

 Cretaceous, varied deposits ; Lower Cretaceous, limestones ; Tithonian, Lias 

 and Bhastic, various ; all these being more or less fossiliferous. W. P. Jervis, 

 however, I Tresori sotteranei dell' Italia, vol. iv, p: 261, 1889, regards the 

 marbles as pre-Palseozoie. A summary of Italian opinion prior to 1878 is given 

 in this Magazine by Professor G. A. Lebour (1878, pp. 289 and 382). He 

 adopts Coquand's verdict for a Carboniferous age. 



2 Unfavourable weather made both shorter than had been intended. 



3 Proceedings of the Cotteswold Naturalists' Field Club, vol. xiii, p. 57. 



4 For the paragraph marked thus § Mr. Winwood is mainly responsible ; for 

 those marked thus IT Professor Bonney. 



DECADE VI. — VOL. II.— NO. VII. 19 



