Page:VCH Suffolk 1.djvu/55

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GEOLOGY Mr. F. J. Bennett has described mottled clay and loam at Wattis- field, from which coarse red pottery was formerly made ; while at the kiln west of the church at Rickinghall Superior, 12 feet of dark lamin- ated sandy clay with freshwater shells and plant remains was observed by him beneath the Boulder Clay and Glacial Sand. Again at Knattishall he noticed about 15 feet of blue and grey clay overlain by 3 feet of sandy loam/ Brickearth also occurs at Reddenhall, Rushbrooke, Wetherden, Stowmarket, Needham Market and Boxford ; some beds, as noticed further on, are found in the Middle Glacial Drift, while other deposits are of distinctly later date. Near Brandon and Santon Downham there are patches of Glacial loam and gravel, the loam being sometimes dug to a depth of 10 feet for brickearth. To these loamy beds, which are more prominently developed on the Norfolk side of the Ouse, Mr. Skertchly applied the name ' Brandon Beds ' — they occur in places beneath Boulder Clay, and from £ome beds which he-regarded as equivalent, he recorded the finding of flint flakes and implements.^ Boulder Clay was not however to be seen above the loam in which the implements were found, and hence doubt necessarily exists with regard to the high antiquity which he assigned to the implement-bearing deposits. Near Mildenhall the loam furnishes a good soil. Loam occurs above the Chalky Boulder Clay at Bury St. Edmunds, often merely as weathered and decalcified surface portion of it. GLACIAL SANDS AND GRAVELS The same difficulty which is experienced with the loams is met with in the case of the older Pleistocene sands and gravels. Cases occur where it is difficult to fix the position of some of the deposits. This is natural enough when we bear in mind that gravels are used up again and again at diflxrent periods, and that contemporaneous organic remains and the evidence of stratigraphical position are often wanting. The greater part of the sand and gravel of Suffolk is beneath the Chalky Boulder Clay and belongs to the Middle Glacial division of S. V. Wood, jun. In the eastern part of the county we find a great spread mainly of sands, often very fine in grain and minutely current-bedded. Much of it looks as if it might have been wind-drifted. The beds extend from Gorleston, Bradwell and Belton to Fritton, Herringfleet Hills, Lound and Hopton ; they occur at Oulton, Carlton Colville and Kirkley, and further south on the higher grounds over much of the eastern margin of the county, where they rest on the Crag series. The sands and gravels are from a few feet up to 100 feet in thick- ness, and they contain in places, especially at Gorleston and Corton, shelly patches somewhat like those of the Crag, and with many broken ' 'Geology of the country around Diss, Eye, Botesdale and Ixworth,' Geol. Survey (1884), p. 12. ' ' Geology of South-western Norfolk,' etc., Geol. Survey (1893), pp. 49-51. 19