Held at: | Hereford Public Library |
Reference: | Local collection |
Source: | Transactions of the Woolhope Naturalists’ Field Club ,1932 & 1952 |
Title: | Guest Contribution: Fossils from Wain Herbert Quarry, Newton |
Place name: | Newton |
Date: | The Devonian Period in Geological time, about 400 million years ago |
Description:
REMARKS ON OLD RED-SANDSTONE FOSSILS IN WAYNE HERBERT QUARRY, NEWTON, HEREFORDSHIRE.
By G. H. Jack, M.Inst.C.E., F.R.I.B.A., F.S.A., F.G.S. (Read 30th June, 1932.)
It was my intention to write a Paper on the fossil fishes of Herefordshire, but as soon as I had settled down to the task I realised how indefinite the present state of our knowledge is in reference to the great sub-division of geological strata known as Old Red Sandstone. I came to the conclusion that it was hopeless for me to endeavour in a short paper to criticise the views of those who had written on the subject previously either in regard to the sequence of the strata or as to the correct inference which should be drawn from the fossil remains.
Speaking broadly, the character of the rocks of the Old Red Sandstone vary considerably in different areas, for instance, whereas it is thought likely that the great thickness of red rocks in Shropshire, Brecon, Hereford, and South Wales as laid down in an inland fresh water lake, rocks of the same age in Devonshire were clearly of marine origin, and further, the Scottish Old Red Series show other distinctive characteristics.
The rocks which surround this spot belong to the lower series of the Old Red Sandstone formation, and while some eminent geologists consider there is no break or unconformity between the upper beds of the Silurian and the lower beds of the Carboniferous, others have strong reason to believe that somewhere in the middle of the series there is a distinct break, and go so far to suggest that even the Old Red Sandstone of Herefordshire may be in some parts marine in character.
Certain it is that the conditions prevailing during the Silurian period were completely altered in the next age, as illustrated by the vast thickness of red rock superimposed on the sandstones and limestones of the Upper Silurian System. Under what conditions this great mass was laid down is still a matter of conjecture, but it is certain that in Herefordshire there must have been large stretches of shallow water disturbed by shifting currents, as indicated by the false bedded sandstone which is clearly seen in the quarry faces where we stand.
A distinctive feature of the Old Red Sandstone of Herefordshire is the scarcity of any fossil remains of aquatic plants or animals. It is thought that the peroxide of iron in the strata has destroyed any remains which might have existed in times past, but whatever the cause, the finding of fossils is exceedingly rare in this particular formation. That being so, you are here to-day to inspect an exposure in the Old Red Sandstone formation on the 700 feet contour line, which contains, a large number of detached bony plates of early fishes, possibly the ventral shields of the Genus Pteraspis.
The finding of so many of this particular part of the fishes presents a problem. How is it none of the other parts occurs? The only theory I can advance, which I do with some trepidation, is that currents which obviously existed at this place separated the parts in accordance with their weight, depositing the heavier ones in one place and the lighter ones in another, but I hope you gentlemen will think the matter out for yourselves and endeavour to find a better solution.
The quarrymen have put aside a considerable number of these fossils, which are open to your inspection, and you will notice that some of the shields still retain the bluish enamel with which they were once coated.
I am sorry not to be able to give you an address in greater detail, and I hope that what I have said will be fairly well understood, and at any rate I trust that this interesting discovery of an horizon in the Old Red Sandstone, which is to some extent fossiliferous, will encourage some of our Members to devote some time to its study, which is not only interesting geologically but plays a great part in building up the beautiful country for which Herefordshire is so famous.
WAYNE HERBERT QUARRY by B. B. Clarke, M.A., M.Sc.
(from the Transactions of 1952)
The rocks exposed here are 700 feet O.D. The quarry lies off the road south west of Newton school, beyond Wayne Herbert farm, overlooking the Monnow valley. The rocks are sandstones and the fossils obtained from them over a number of years indicate that they belong to the zone of Pteraspis crouchi in the Dittonian. The fossils are now housed in the British Museum and are described as being in a superb state of preservation. This quarry was selected for a visit from members of the International Geological Congress in 1948. Dr. E. I. White and Mr. H. A. Toombs prepared a guide for this excursion, and they have kindly provided from this and their other records the following list of fossils from this important site.
Most of the fossils are Ostracoderm fishes, but in addition specimens of two different classes of Arthropods—Crustaceans and Arachnids—have been found.
Among the Ostracoderms Pteraspids and Cephalaspids are the most common. Besides the zone fossil, P. crouchi, there are three distinct varieties of Pteraspis rostrata-toombsi, virgoi and waynensis. Poraspis sericea has also been found here. Twelve distinct species of Cephalaspis occur including C. jacki. Eight of the twelve are peculiar to this quarry. Weigeltaspis also occurs. In addition to these Ostracoderms fragments of Acanthodians of various sorts have also been found-The Crustacean finds are also of great interest and include Prearcturus gigas believed to be an Isopod. The Arachnid finds are those of the large Eurypterid Pierygotus cf. anglicus. Thislarge scorpion-like animal is well known from the Ludlovian rocks and passes up from the Silurian into the Grey Downtonian where it has been recorded from Ledbury. It is however very unusual to find it as high up the Old Red Sandstone succession as this.
On the occasion of the Club's visit we found the fossil horizon to be a band of very hard greenish grit near the bottom of the quarry. A complete ventral disk of P. crouchi was found and some other Ostracoderm fragments. There were also plant fragments.
Geological techniques and knowledge has moved on in the 75 years since the fossils of Wayne Herbert were first reported. A present day appreciation of their significance can be found on the JNCC website.
Observations:
Gavin Hayes Jack was the County Surveyor and Bridgemaster of Herefordshire County Council from 1907 to 1933. He was a prominent member of the Woolhope Club and contributed articles to the Transactions. He was President of the Club in 1916. The quarry at Wain Herbert farm was worked for local road stone for many years and Mr Jack became familiar with it in this context.
B. B. Clarke was an eminent local Geologist and was President of the Club in 1940.
The two items above are reproduced from the Transactions of the Woolhope Naturalists’ Field Club with the permission of the Central Committee
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