Implements of Sub-Crag Man in Norfolk

Abstract

Few English deposits have aroused more disputation among geologists than the Crag beds of Norfolk and Suffolk, and on many of the points raised there is as yet no general agreement. This more particularly applies to the sands, gravels, and clays associated with the Norwich Crag, one school considering them part of the Crag formation and therefore Pliocene, and another believing them to be glacial and Pleistocene. Doubt on this matter has had an important bearing on the discovery of Sub-Crag implements in Norfolk, though I believe that the evidence is now incontrovertible. With regard to the basement-bed of the Crag, whether of the Coralline, Red, or Norwich Crag, which appear to have been successive deposits in the order given, the geological evidence as to position and antiquity—though not as to the conditions under which it was deposited—is not disputed. Mr. F. W. Harmer, F.G.S., says:—“In consequence of a combined movement of elevation iu the southern part of this region, and of subsidence towards the north, the whole Crag basin moving as on a pivot, its southern margin was gradually shifted, the sea retiring towards the north.