Little Cornard Brick Pits

CRAG

PITS

IN

CHILLESFORD—BUTLEY—SUTTON

AREA

225

There is a smaller remnant of Coralline Crag at Tattingstone but the largest extends from the mouth of Butley Creek, Gedgrave, to the Aide, which cuts through it, and extends beyond Aldeburgh to Thorpeness where it is not now visible above sea level. However, blocks of it are cast ashore by storms.

T h e Coralline Crag was deposited in a sea of which the climate was like that of the Mediterranean. It is now regarded as the only Pliocene deposit in England, all the other crag beds having rightly been moved from the Pliocene to the Pleistocene. Actually there are very few corals in this crag—only about 4 species.

H.

E.

P.

SPENCER.

L I T T L E CORNARD BRICK PITS These exposures visited by the Society lOth. Sept., 1955, exhibit several points of unusual interest. Thanet Beds of The Lower London Tertiaries occupy most of the lowest, most westerly pit, with a fragment of Reading Beds above.

Sands and gravels overlie these, often showing remarkable contortions from a Stour Valley glacier. Above and cutting down into these is a complicated boulder clay series in which is included a lake deposit of the finely laminated silts known as " varves " in which each pair of coarse-fine laminae is generally held to represent a year's deposit. If so nearly 4,000 years would seem to have been occupied by the deposition of the section seen— some 15 feet thick—the top of which is very chalky.

T h e more typical Chalky Boulder Clay which follows this appears to include several boulders of reconstituted chalk, one over thirty yards long and containing apparently Pleistocene freshwater shells.

T h e question then arises : are these true boulders ? In any case one must first envisage a Pleistocene glacier or lce sheet eroding chalk and pouring its chalky milk into a lake, thus forming a lacustrine silt so rieh in calcium carbonate that one may call it a reconstituted chalk. If the masses are not boulders the deposition

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LITTLE CORNARD BRICK PITS

took place on this spot and that is the end of the story—except that the evolution of the valley removed the lake and most of its deposits. But if future excavation (if possible) shows them to be boulders, the deposition will have occurred elsewhere and one must invoke a further chapter to their history and probably another glacial period, since the reconstituted chalk, after consolidation and probably uplift, must have been ploughed into by a later glacier which broke off and carried away these pieces and, melting, dropped them here.

E L E P H A N T AT STOKE BY NAYLAND.—Late in October, having heard from the foreman of the Alresford Sand and Ballast Co's pit at Thorrington St., Stoke by Nayland, of a large and curious object in his quarry, I went there and found a good sized tusk of a mammoth, Elephas primigenius, lying conveniently on an almost level platform, still in situ, some 16 feet down in the river terrace gravels laid down at the junction of the ancient Stour and Box. Originally about 9 feet long, it was 6 ft. 3 in. (central measurement) when I first saw it and rather over 7 in. in diameter, the dragline excavator having caught its point and shattered two feet of it or more before the operator with remarkable promptitude spotted it and stopped the machine. Some 6 in. of the hollow and therefore fragile proximal end feil off later. It was the left tusk of almost certainly a male elephant as suggested by Mr. H. E P. Spencer who came over from Ipswich to take photographs.

One could well imagine the dead animal, swept down by the torrent, grounding at the spot and lying on its left side with one tusk buried in the gravel—tili the rest of the body feil to pieces and was carried away, leaving this relic.

As it was not wanted by Ipswich Museum, where there are several specimens, nor by that of Colchester which as yet does not go in for natural history, I carried out the necessary hardening and strengthening process myself. The whole thing was a mass of cracks, one might almost say of fragments though in their proper position, and pieces were liable to fall off at the slightest provocation. After due preparation, however, it was removed to my home more or less intact and is now undergoing further treatment.

F. H. A.

ENGLEHEART.