452 Wood and Harmer— Geology of Norfolk and Suffolk. 

 nsroTiOES OIF ^y^:E!:]y^OII^s. 



Abstract of a Paper on " The Glacial and Post-glacial Struc- 

 ture OF Norfolk and Suffolk." By Messrs. Searles V. Wood, 

 Junr., and F. W. Harmer.^ 



(Read before the British Association at Norwich, August 20, 1868.) 



THIS paper was a summary of the results arrived at by the 

 authors, from a survey and mapping of the Crag and Glacial 

 beds of Norfolk and Suffolk, upon the Ordnance (one inch to the 

 mile) map, which they have been carrying on during the last four 

 years. The paper was illustrated with a large map, constructed 

 from their survey map, and copious detailed sections, traversing the 

 counties in various directions, without which the paper itself is diffi- 

 cult to be understood. The principal results at which the authors 

 have arrived at are as follows : — 



That the Fluvio-marine Crag of Thorpe, and Bramerton, and of 

 Wangford, Bulchamp, and Thorpe, near Aldboro', is coeval with the 

 newer part of the Ked Crag. 



That the Crag of Burgh, Horstead, and Coltishall, in the Bure 

 Valley, is a fluvio-marine development of the Chillesford shell bed, or 

 Crag of Easton and Aldeby, which, divided from the Eed and Fluvio- 

 marine Crag by an interval of sand of varying thickness, overlies the 

 Eed Crag at Chillesford, and the Fluvio-marine Crag (or old Nor- 

 wich Crag) at Thorpe and Bramerton. 



That the so-called Crag of Belaugh, in the Bure Valley, and the 

 so-called Crag of the Weyboume and Cromer coast, are newer than 

 the Chillesford beds (which, unless the pebble beds next mentioned 

 be a still higher part of the Crag series, form the uppermost of the 

 true Crag series), being characterised by the presence in profusion 

 of a shell unknown to any bed of the true Crag series from the 

 Chillesford clay downwards — viz., the Tellina solidula ; and were 

 introduced after an elevation of the Crag area had converted the 

 southern portion of it into land, and given rise over the northern por- 

 tion to extensive sands with pebble beds, which rest on and indent 

 the Chillesford clay in that northern portion. These sands with 

 pebbles occupy in the south of Norfolk, and north of Suffolk, the 

 same place relatively to the contorted Drift as is occupied on the 

 Cromer coast by the Weybourne sand (or so-called " Crag" of the 

 Cromer coast), the Cromer Till, and the indenting sand (or bed C 

 after-mentioned). These pebble beds may thus represent in time 

 either the whole or any one of the formations A, B, and C (described 

 further on) ; or they may form merely the closing bed of the true 

 Crag series,^ in which case the Weybourne sand, the Cromer Till, 

 and bod C are entirely unrepresented in the south of Norfolk and 

 north of Suffolk. 



That the forest beds of the coast extending from Eccles to 



^ The abstract has been most obligingly prepared and furnished by the authors ex- 

 pressly for publication in the Geological Magazine. — Edit. 



2 The authors arc inclined to think that the second of these alternatives is the true 

 one ; and they hope to clear up the point by means of a fossiUferous pebble-bed near 

 Bimgay. 



