Dr. Woolacott — A Raised Beach in Durham. 71 



■estuarine deposit, also of somewhat similar age, has been described 

 from Kirmington, in Lincolnshire, at an elevation of 60-80 feet,^ 

 and that^ there are evidences of late Glacial and Post-glacial uplifts 

 in the Wash ^ and West Norfolk ^ and other parts of England. 



While the Raised Beach at Easington is in itself of much interest, 

 yet it is, as stated in the beginning of this paj)er, in connexion with 

 the formation of a considerable part of the upper sands, leafy, 

 stony, stoneless, and prismatic clays that the uplift proved by it 

 (and the higher beach in Noi'th Durham) becomes of importance in 

 general Glacial geology. It is clear that much of the material along 

 the east coast of England and up the buried Pre-glacial valleys of 

 the " Tyne " and " Tees "/ etc. — which has been considered to 

 be true boulder clay is in reality reassorted clay (both stony and 

 stoneless clays), or which has been conjectured to have been 

 deposited in Glacier-lakes (leafy clays), or which has been thought 

 to be of Fluvio-glacial origin (sand and gravel) — is of estuarine 

 and marine origin, and was formed when the coastal region was 

 embayed near the end of the Glacial period. The scarcity of the 

 fossil remains in the clays and sands of estuarine origin may be partly 

 owing to the turbid nature of the waters brought about by the rapid 

 denudation of the Glacial and Fluvio-glacial deposits, and also to 

 the comparatively short period and to the rather rapid nature of the 

 movements during which they were deposited. It seems obvious 

 that after the retreat of the ice-sheet and the incoming of the sea 

 a marine fauna would be able to establish itself much more quickly 

 than an estuarine or freshwater one in the north of England. Tracks 

 of some form of locomotive life are common on some of the layers of 

 the leafy clays, but no shells have been observed by any geologist. 

 Shells and bored pebbles are reported to have been found in some 

 clays in a brickfield near Harton, but Mr. E. Merrick, who has made 

 a detailed study in the field of the clays of the Tyne and Wear 

 districts, has never found any shells in them, although he has 

 verified the occurrence of the bored pebbles. A molluscan 

 estuarine fauna has not yet been proved to have inhabited the Tyne 



1 B.A. Report, Cambridge, 1904, p. 272. In this section there is a deposit 

 of laminated clay with estuarme shells, etc., at about 70-80 feet above sea- 

 level. It is underlaid by Purple Drift (= Main or British Drift of Durham 

 Coast) and above it is a well-worn beach -shingle, prmcipally of battered flints 

 and a clay with foreign stones. Is this clay a true boulder clay ? Is it Hessle 

 clay ? If so, it is the equivalent of the Durham Prismatic Clay and other 

 reassorted clays which are not of direct Glacial origm. The Kirmmgton 

 deposit is, in my opmion, late Pleistocene, and may be similar in age to the 

 raised marine deposits of the Durham littoral and contemporaneous with some 

 of the leafy and other clays of the Tyne Valley, etc. The evidence does not 

 appear to be sufficient to prove the Kirmington deposit to be an Interglacial 

 (or even an Interval) deposit, see Lamjilugh, " The Interglacial Problem iu 

 the British Isles " : International Geological Congress, Canada, 1913, p. 3. 



^ Geology in the Field, p. 175. 



* Woodward's Geol. of England and Wales, p. 555. 



* e.g. the Brown clay. Common clay, etc., of the Tyne valley. 



