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Bed was in 1746 by W. Arderon,* though the teeth of elephants found near Cromer were known from an earlier period; but it is to R. C. Taylor that the first geological description is due, and it is really wonderful how well at so early a date as 1822 and 1827+ he grasps the subject. Lyell in 1840 also wrote one of the best descriptions of the Drift deposits extant. Almost every geologist of note has written more or less upon the subject, and the latest information we can refer to is contained in the Survey Memoir by Mr. Clement Reid “On the Geology of the Country around Cromer, 1882,” accompanied by a very detailed section of the cliffs from Happisburg to Weyburn.
There is, unfortunately, a great deal of discordant information in existence, every observer taking a more or less individual view and differing from those who have gone before and even with himself. Doubtless this is due to two causes--the inconstant nature of many of the beds, the difficulty of examining them except in winter after storms, and then because of the talus, only from time to time, and in places; and, when found, the further difficulty of distinguishing and separating them.
Before describing the drift deposits, it will be well to glance at the beds underlying them. Without endorsing Mr. Clement Reid's section in every particular-- for I think there is much that is doubtful and much that will bear a different interpretation to that which he puts on it—we may recognise from the careful way in which the section has been constructed that it will form a good basis for future investigations. There is a great deal both of observation and inference—but especially the latter which permeates the whole in a way difficult to separate—which must be confirmed by others before they can be accepted. More especially is this caution needed when we find that in no one particular, on any subject, does he
* See“ Geological Survey Memoir of the Geology of the Country around Cromer," by Clement Reid (page 20.)
† “On the Geology of East Norfolk."-Phil. Mag., 1827. # "On the Boulder Formation of East Norfolk.”—Phil. Mag., May, 1840.
unqualifiedly agree with any other geologist. And I may be permitted further to add that there is very little of the con siderable amount of physical theory stated or involved in the Memoir with which I can myself agree.
The succession now given is :-Chalk, Weyburn Crag, Lower Fresh Water Bed, Forest Bed (estuarine), Upper Fresh Water Bed, Leda Myalis Bed, Arctio Fresh Water Bed. This ends the Pliocene series ; then come the Glacial : 1st Till Intermediate Till, 2nd Till, Contorted Drift, Glacial Gravel and Sand of various ages, Valley Gravel and Loam of Post Glacial age finishing the whole. The Forest Bed, though the name is retained for an estuarine series from 1 foot to 21 feet thick, is practically abolished, the stools of trees, thought by all other observers to have been rooted in the ground, being looked upon as snags floated down by a river and deposited in its estuary, this river being no other than our old friend the Rhine, of which, to use Professor Hull's phrase, a Palæo-Physiographical Map is given. As I am writing elsewhere on this subject, I shall say no more.*
The Drift deposits I personally examined in 1881† from Mundesley to Weyburn. At Mundesley, after leaving the celebrated Post Glacial Valley cut through the beds, in which interesting mammalian remains have been found, we come upon a chalky Till (Reid's 2nd Till), much resembling what is called the great chalky boulder clay, overlain with stratified sunds and gravels, and over these stratified sands are in places gravels that I believe to be post glacial. Beneath this Till the
survey section states there occur clay, loam, and sand, with fresh water shells and arctic plants (Salix Polaris, Betula Nana, dc.) At one point the upper surface of the chalky clay presented a very defined line of erosion in the form of two anticlinals overlain with stratified gravels. Beyond this was bedded stratified chalky clay overlying the
* See “ Some suggestions on the Cromer Forest Bed.” Geo. Mag. May, 1883.
t“On the Chalk Masses in the Contorted Drift of Cromer " Q.J.G.S., May, 1882.
Till, the base being concealed by talus. As we get towards Trimmingham the sands and gravels hitherto roughly stratified begin to be affected by contortions, the first contortion shewing a tongue of the chalky boulder clay (Cromer Till) forced up eastwardly into the san is above. Beyond, the chalky Till takes the form at the surface of a section of a ridge with concave sides, the sands above being contorted, while at the east side they are level and stratified. The next section I have is a sketch of the Southern Chalk Bluff, which is shewn on my diagram. Above this lies chalky Till, with a very distinct contorted line of erosion separating it from the overlying sands which appear to be, a certain distance above, regularly bedded. On the right hand flank of the chalk
my sketch shews sand and gravel lying on it. A talus of drift had fallen down through the depression in the centre of the bluff. Up to this section there was a well-markedline of division or erosion at the top of the Till. Beyond this point and before coming to the Northern Bluff, my sketch shews a ridge of chalky Till rising into the contorted sands. We now arrive at the Northern Chalk Bluff, the subject of so much speculation. It is represented in my section sheet figs. 1–4* When I saw it, it was capped with contorted drift, mostly sands, but the base of the cliff of drift flanking it on either side was obscured by talus. I judged the Ohalk Bluff projected about 15 yards beyond the face of the line of cliff. I will return to this subject later. Between the Northern Bluff and Sidestrand is seen a banded arrangement of drift lying on Till. It has been pushed up, and even beyond the vertical at one place, as figured, and bent back horizontally and upwards as shewn in figure 6. Another contortion nearer Sidestrand shews a banded bed bent back into the figure S. At various points beyond this, before reaching the tunnel at Sidestrand, are to be seen at the base
* These and the following figures agree with those in my paper on the “Chalk Masses in the Cromer Drift" Q. J. G. S., May, 1882, which can be referred to for the illustrations, as they are numbered as here given.
of the cliff stratified beds of flint gravel with laminated sand and clay of yellow, white, and blue colours. Some of the beds of sands and gravels are false bedded. These beds rise from 5ft. 6in. to 15ft. above the beach. Unfortunately, when I saw these beds they could only be distinguished by scraping the superficial dirt from them, and I had not time to attempt to separate and trace them. On the Survey section they are
, all classified and coloured together, but it is stated “ the upper part of the Forest Bed (shewn in the cliff) is here very sandy and penetrated by small roots.” According to the Memoir, the Leda Myalis bed does not occur, or rather has not been recognised between Beck Hithe and Mundesley; so this, according to Mr. Reid's interpretation, must all be “ Forest Bed”, certainly, from what I saw of it a very misleading title.
Between Sidestrand and Cromer the cliff is all of contorted drift. There are two chalk boulders at the base and some masses of reconstructed chalk, quarried for lime, in the contorted drift near the lighthouse.
North of Cromer the drift becomes very much contorted, twisted in all sorts of fantastic shapes, with stratified bands bent backwards and forwards like a ribbon. Side or cross sections which can be seen in places shew that this twisting and knotting is the same at right angles to the cliff. A few yards sliced off the cliff at intervals would sbew sections which would vary as much as slabs of figured timber sawn off the bole of a tree. In places the Till is to be seen andis. turbed, but in others worked and kneeded up into the overlying contortions. It is here that the enormous masses of chalk are found embedded in the contorted drift. The two phenomena are evidently related as cause and effect. The chalk masses are specially described in my paper, already referred to in the Q.J.G.S., so I need not repeat here what I have there said. Beds of stratified sand are to be traced at the base of the cliff, with in places interlaminations of clay.
The relations of the various beds, basing my views on what
I have myself seen and from a study of the information contained in the Survey Memoir, seem to bear this natural interpretation. The Forest Bed, notwithstanding Mr. Reid's peculiar views, is, I believe, a genuine Forest Bed ; knocked about and denuded it may be. I point to the fact that the forest portion occurs in the greatest profusion at the base. This is evident from the detailed sections of the Memoir. Mr. Savin, of Cromer, also informed me that he had seen hundreds of stumps of trees standing erect on the foreshore, although all those he had seen dug up had roots only a few feet long. Other geologists from the time of R. C. Taylor have seen the same.* These may have been locally moved as happens to some of the stools in our Post-glacial forest bed ; but it is straining at a gnat and swallowing a camel to suppose that the trees could have been cut off in hundreds at a particular level, floated down a river and replanted erect in such profusion. It appears to me the demand to be shewn fibres and small roots is asking for too much proof; we know that these decay and rot more readily than the wood. Geology is full of such difficulties, and often the only course open is to exercise common sense and weigh probabilities. According to my own view, the evidence all points to forest growth in situ, after denudation, and the laying down of the estuarine beds with which much of the remains of the forest have been worked up and mixed. The interstratified fresh water beds are only what are commonly met with in estuarine series. The Arctic conditions have undoubtedly supervened between the laying down of the estuarine series and the deposit of boulder clay, and may possibly be represented by a land surface (Arctic fresh water bed). The rootlet beds are younger than the estuarine series, but it is not easy to trace them out from the
* Mr. R. C. Taylor has minutely described the “ Fossil trees" and the strata in which they were embedded. He had the best of opportunities for examination during the excavations for the sea wall at Cromer, in 1825, and the evidence he gives of their being in their place of growth seems to me quite satisfactory.-See Trans. of Geo. Soc.—2nd Vol. 2nd Series, quoted by Mr. Henry Norton, F.G.S. in a paper to the Norwich Geo. Soc., May, 1877.