Page:VCH Suffolk 1.djvu/57

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GEOLOGY from the Westleton shingle.' It is a subdivision that may be repre- sented in the Crag Series at Easton Bavent and Southwold, and it may be remarked that the pebble gravel at the northern end of Southwold cliff, regarded by Prestwich as ' Westleton Beds,' ' is clearly a part of the Crag Series, which probably extends over the whole of Southwold. We find, in fact, re-arranged Chillesford Clay in the Middle Glacial sands at Dunwich, shingle in the sands at Pakefield and Kirkley, reconstructed Crag in the sands at Gorleston. As before mentioned, we find on the Chalk tracts in north-western Suffolk much sand of no great thickness, as on Lakenheath Warren. It is a region known as the ' Fieldings,' and noted as subject to sandstorms. As long ago as 1668, Thomas Wright gave a brief description of the devastation caused by the drifting of sand, but the trouble has been exaggerated by subsequent writers owing to the title of Wright's paper, ' A curious and exact Relation of a Sand-floud, which hath lately over- whelmed a great tract of Land in the County of Suffolk.'^ He remarked that previously the sand had been drifted by the south-west winds over many acres of land, but that it had first reached the bounds of Downham (known as Santon Downham or Downham Arenarum) some 30 or 40 years prior to 1668, and eventually a number of meadows and pastures were ruined by ' the extream Sandiness of the Soyl, the levity of which, I believe, gave occasion to that Land-story of the Actions that use to be brought in Norfolk for Grounds blown out of the Owners possession.' Until improved by the application of marl this was no doubt the poorest land in the county. The greatest thickness of sand and gravel (mostly sand) is 100 feet, recorded at Market Weston near Bury St. Edmunds, in which district the beds rest on Chalk. Coarse mixed gravel, often with lumps of Chalk, occurs in places below, in, and above the Chalky Boulder Clay, and is perhaps more intimately connected with the Boulder Clay than the mass of the Middle Glacial sands and pebbly gravels. It may mark places where the debris-laden ice was melted, and its constituents were distri- buted by torrential streams. Thus gravel with boulders of limestone, sandstone and grit occurs beneath Boulder Clay at Great Horringer ; coarse gravel is hkewise found at Gallows Hill, south-east of Needham Market ; and a mass of chalky gravel was observed in the Boulder Clay at Halesworth. Some of the patches of gravel now seen on Boulder Clay may have occurred originally in it before the surface had been lowered by denudation. Coarse gravel with large flints occurs at Cockfield and Lavenham, and gravel over Boulder Clay has been exposed to a depth of i 2 to 18 feet at Tostock, Elmswell, Woolpit and Shelland ; a mass of it extends from Great Waldingfield to Cornard Heath, Newton Green and Assington ; it is met with also to the north and west of Lowestoft and Gunton, north of Hopton and at Herringfleet Hall. Where the gravel occurs at ' ^art. Journ. Geol. Soc. Ivi. 724 ; Proc. Geo/. Assoc, xvii. 453. » Ibid, xxvii. 462. ' Phil. Trans, iii. (1668), 725. 21