[ 758 ] 

 LXXXI. Proceedings of Learned Societies. 



GEOLOGICAL SOCIETY. 



[Continued from p. 632.] 



May 13th, 1914.— Dr. L. Smith Woodward, F.R.S., President, 

 in the Chair. 



r PHE following communications were read : — 



1. ' The Scandinavian Drift of the Durham Coast, and the 

 General Glaciology of South-East Durham.' By Charles Taylor 

 Trechmann, B.Sc, F.G.S. 



The present communication summarizes observations carried out 

 for some time on the superficial deposits of South-East Durham 

 and the lower Tees Valley. It practically embraces the area repre- 

 sented, on the two Geological Survey 1-inch Drift maps, Sheet 103 

 N.E. (New Series 27) and Sheet 103 S.E. Evidence relating to 

 the pre-Glacial levels and contours of the land in the Permian and 

 Triassic areas lias been collected and examined. This supports 

 the conclusion that, immediately prior to the oncoming of glacial 

 conditions, the land stood at not less than 100 feet above its 

 present level. 



The fissures and depressions of the Middle and Upper Magnesian 

 Limestones on the eastern side of the Shell-Limestone reef have 

 been instrumental in preserving relics of the material brought by 

 the earliest ice- sheet which invaded the district from the "North 

 Sea. This material proves to be absolutely devoid of the ordinary 

 glacial erratics of the North of England and Scotland, found in 

 the overlying main Drifts. Several narrow vertical fissures are 

 filled with masses of red sandstone, red, grey, and green marl, peat 

 and masses of peaty wood, and Magnesian Limestone, both of 

 immediately local occurrence and of material strange to the 

 district. 



The Scandinavian Drift proper occurs about midway between 

 Hartlepool and Seaham Harbour, and occupies a position near the 

 middle of the stretch of coast-line where the red fissures are seen. 

 It has been preserved in a pre- Glacial depression and fissure in the 

 underlying Magnesian Limestone, extending over slightly under a 

 quarter of a mile. It is represented by a transported shelly clay 

 containing a fauna of Arctic affinities, which recalls that of some 

 of the basement clays of Flamborough and Holderness. Among 

 other erratics, a big boulder of titaniferous syenite was found resting 

 immediately upon the Magnesian Limestone near the southern end 

 of this section ; special notice was taken also of a very big laurvigite- 

 syenite (5 feet long) and two rather smaller rhomb-porphyries 

 lying on the shore opposite this place. 



All the stones (between 300 and 400 specimens) found in this 

 clay were collected and examined. The greater part of them are 

 well- glaciated crystalline rocks, many of which (the typical Chris- 

 tiania eruptives) certainly are, and the greater part may be, of 

 South Norwegian origin. Permian limestone, red sandstone, Chalk, 

 and splintered flints also occm\ 



