Notes on Some Suffolk Crag Localities

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NOTES ON SOME SUFFOLK CRAG LOCALITIES R. A. D .

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MARKHAM

The Coralline Crag at Tattingstone

SECTIONS

at Tattingstone, near Ipswich, are of interest in showing Red Crag resting on Coralline Crag; one such section was figured by Prestwich (1871). This small outcrop, on the site of a proposed reservoir, is 10 miles from the next Coralline Crag outcrop near Sutton. An attempt to dig to the base of the Coralline Crag at Tattingstone Hall (TM 143374) was made by C. Allen, B. Keeble, and the writer in April, 1963, by kind permission of Mr. R. Caldwell. The base was not reached because of the presence of water in the excavation; water also stopped early attempts by Charlesworth (1835) and Lyell (1839). About 4J feet of Coralline Crag was exposed below the Red Crag, and digging showed another feet (2 feet 5 inches under water), making a total of 11 feet of Coralline Crag without reaching the base. Lithologically the Coralline Crag was as described by Whitaker (1885), but the bottom foot was orange-coloured. A number of bands of nodules (of indurated shelly limestone) were found, the nodules 7 feet 9 inches from the top of the Coralline Crag in the section measured being associated with a pink-coloured band. Only a few fossils (Lyell, 1839) have been recorded from the Coralline Crag at Tattingstone, probably because of the fragmentary condition of specimens. The following were found in 1963:— Bivalve molluscs Area lactea, Limopsis pygmaea, Glycimeris glyeimeris, Astarte, Woodia digitaria, Ostrea, Anomia, Corbula, Spisula, Pteromeris corbis, Diplodonta rotundata, Chlamys, Ensis, Venus ovata. Gastropods 'Natica', Turritella, Scala, Calliostoma. Bryozoans, including Cellaria. Coral—Sphenotrochus intermedius. Echinoid spine; Barnacles; Foraminifera; Fish otoliths. Boswell (1913) gives a sketch-map of the Coralline Crag outcrop at Tattingstone. Its known underground extent was slightly enlarged in 1967 when Mr. R. F. Harwood brought the writer's attention to a temporary excavation at Tattingstone Place (TM 140368); this section showed over a foot of Red Crag resting on about 4 feet of Coralline Crag.


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