Field Meeting in the Gault at Small Dole, near Henfield, Sussex: Sunday, 14 August 1960

Abstract

THE PRINCIPAL object of this meeting was to examine and collect fossils from the Gault (Middle and Upper Albian) exposed in the British Portland Cement Company's c1ayfield at Horton, one-quarter of a mile south of Small Dole (51/-). A short visit was first made, however, to the Henfield Brick Company's working in Weald Clay, one mile south of Henfield (51/-). Both exposures are situated on the west side of the A.2037, Henfield to Upper Reeding road. The Henfield Brick Co's. pit exposes some thirty feet of ferruginous clays, belonging to the Upper Weald Clay series, with, near the top, a thin seam of limestone crowded with shells of the freshwater gastropod Viviparus (Paludina) fluviorumJ. Sowerby. This Paludinalimestone, which is also known as Sussex Marble, yielded, as did the surrounding clay, bones and scales of the Wealden fish Lepidosteus, Large pieces of fossil wood in which the original cellulose has been mainly replaced by iron sulphide (pyrites) occurred on the weathered clay slopes, and employees of the company reported the finding there of large bones (presumably reptilian) during the summer of 1959. On arriving at the Gault exposure at Small Dole, the party took advantage of a temporary halt in the proceedings, made necessary by a heavy shower of rain, to consume lunch, after which examination of the extensive workings commenced. This clayfield is being developed rapidly and is, without doubt, already the largest man-made Gault exposure in England. The Gault, which is used together with Chalk in the manufacture of cement, is removed by multi-bucket excavator, working at the pit-side, and by bulldozers working across a large, flat arena. Conveyor belts transport the clay to a gigantic mixing and grinding tank from which it is pumped, as a high viscosity suspension in water, through twin pipelines to the company's Shoreham works at Reeding, two and a half miles to the south. The pit exhibits some ninety feet of highly fossiliferous clays of which fifty-five feet are referable to the Lower Gault and thirty-five feet to the Upper Gault. Ammonites collected over a period of several years show that the lowest part of the section is in the upper intermediusSubzone of the dentatus Zone, and the highest part in the orblgnyi Subzone of the