Throughout the greater part of Moen the strata of the drift are undisturbed and horizontal, as are those of the subjacent Chalk; but on the north-eastern coast they have been throughout a certain area bent, folded, and shifted, together with the beds of the underlying Cretaceous formation. Within this area they have been even more deranged than is the English Chalk-with-flints along the central axis of the Isle of Wight in Hampshire, or of Purbeck in Dorsetshire. The whole displacement of the Chalk is evidently posterior in date to the origin of the drift, since the beds of the latter are horizontal where the fundamental Chalk is horizontal, and inclined, curved, or vertical where the Chalk displays signs of similar derangement. Although I had come to these conclusions respecting the structure of Moen in 1835, after devoting several days in company with Dr. Forchhammer to its examination,*
(* Lyell, "Geological Transactions" 2nd series volume 2 page
243.)
I should have hesitated to cite the spot as exemplifying convulsions on so grand a scale, of such extremely modern date, had not the island been since thoroughly investigated by a most able and reliable authority, the Danish geologist, Professor Puggaard, who has published a series of detailed sections of the cliffs.
These cliffs extend through the north-eastern coast of the island, called Moens Klint,* where the Chalk precipices are bold and picturesque, being 300 and 400 feet high, with tall beech-trees growing on their summits, and covered here and there at their base with huge taluses of fallen drift, verdant with wild shrubs and grass, by which the monotony of a continuous range of white Chalk cliffs is prevented.
(* Puggaard, "Geologie d. Insel Moen" Bern 1851; and
"Bulletin de la Societe Geologique de France" 1851.)
(FIGURE 47. SOUTHERN EXTREMITY OF MOENS KLINT (PUGGAARD).
A. Horizontal drift.
B. Chalk and overlying drift beginning to rise.
C. First flexure and fault. Height of cliff at this point,
180 feet.)
(FIGURE 48. SECTION OF MOENS KLINT (PUGGAARD), CONTINUED
FROM FIGURE 47.
S. Fossil shells of recent species in the drift at this point.
G. Greatest height near G, 280 feet.)
In the low part of the island, at A, Figure 47, or the southern extremity of the line of section above alluded to, the drift is horizontal, but when we reach B, a change, both in the height of the cliffs and in the inclination of the strata, begins to be perceptible, and the Chalk Number 1 soon makes its appearance from beneath the overlying members of the drift Numbers 2, 3, 4, and 5.
This Chalk, with its layers of flints, is so like that of England as to require no description. The incumbent drift consists of the following subdivisions, beginning with the lowest: