C— GEOLOGY 73 



but their relationship to the river-gravels, and particularly to the last 

 cold episode of the Barnwell Station Beds, has not been determined. 



The succession at the well-known locality of High Lodge, Mildenhall, 

 raises problems which have not yet been solved. Prof. Marr recog- 

 nised an Upper and a Lower Chalky Boulder Clay separated by gravels 

 and brickearths which have yielded numerous implements of so-called 

 Mousterian type, but including hand-axes related to the pre-Mousterian 

 industry in Germany. The workmanship resembles somewhat that 

 of the Clactonian flake-industry and may, according to Miss Dorothy 

 Garrod, be a development from it. In the present state of our know- 

 ledge, we can only correlate the Upper Boulder Clay of this area with 

 the Upper Chalky Drift, and the Lower Boulder Clay with the Chalky- 

 Jurassic facies. 



Traces of Man's existence in the area after the formation of the Upper 

 Chalky Drift of southern Norfolk and Suffolk can be found only in the 

 surface-deposits. These usually occur on the slopes or floors of valleys. 

 Mr. Reid Moir has found what he claims to be implements of Mousterian 

 manufacture in the Upper Chalky Drift (Boulder Clay) near Ipswich, 

 but agreement on the nature of the flaking has not yet been secured. 

 Moreover, he has recently stated that he has found the same type in 

 the upper part of the Chalky-Jurassic Boulder Clay — a claim which, if 

 admitted, would be difficult to reconcile with our ideas of the strati- 

 graphical sequence. However, on the slopes of a small valley near 

 Ipswich Mr. Moir has found a succession of floors, the two uppermost 

 of which contain Upper Mousterian and Aurignacian implements respec- 

 tively. These floors prove that the local and minor topographical 

 features must have attained their present form before Upper Mousterian 

 times, for only hill-wash (containing Solutrian blades) covers the deposits. 

 Even more significant is his discovery of an excellent section at the 

 bottom of the Gipping Valley, where at a depth of 15 feet below the river 

 alluvium (about i foot to 5 feet below O.D.) is a peaty loam containing 

 a floor of Early Mousterian (Combe-Capelle) age, associated with bones 

 of reindeer. This peaty bed was succeeded by a blue loam with Early 

 Solutrian blades, the whole being covered by gravel with many derived 

 implements. The surface-deposits of sand and loam here contain 

 Magdalenian and Neolithic types. In the estuary of the river Orwell, 

 below Ipswich, the well-known ' Submerged Forest ' or peat-bed, lying 

 at about 30 feet or more below O.D. and containing teeth of mammoth, 

 is covered first by shingly gravel and then by alluvial mud with 

 peaty partings. At the base of the latter is a floor, believed to be of 

 Magdalenian age. 



The relationship of the industries of Aurignacian and Magdalenian 

 Man to the glacial episodes thus cannot be determined in the Ipswich 

 district, but there is evidence, like that in the Fen country, of a subsi- 

 dence since Solutrian times. For the requisite connecting link we must 

 turn to north-western Norfolk, where there is a Boulder Clay still younger 

 than any yet mentioned. This ' Brown Boulder Clay ' was recognised 

 long ago by the officers of the Geological Survey as the latest Boulder 

 Clay of the Wash area, being very different lithologically from the Chalky 



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