ANNIVERSARY ADDRESS OF THE PRESIDENT. Ixvii 



that in Ireland conditions permitted the deposit of the cretaceous 

 rocks in that portion of the British area. 



Ranging doAvn from Somerset and Wilts into Dorsetshire, the 

 cretaceous rocks are seen overlapping various members of the oolitic 

 series, so that in the vicinity of the country noticed by Mr. Weston, 

 the great clay deposit known as the Oxford clay supports cretaceous 

 rocks. In a section given by Mr. Weston he shows a continuation of 

 the Hastings sands as reposing on the Purbeck beds, founding this 

 view on the organic remains discovered in the beds, and on their 

 general character ; and he also shows some tertiary accumulations 

 where they had not been previously noticed. The line of section 

 where the Ridgway fault traverses it exposes a clay, which from its 

 appearance and fossils Mr. Weston regards as a portion of the Oxford 

 clay beneath, forced up through the line of fracture, so as to occupy 

 a position between the greensand beneath the chalk and the beds, 

 supposed to be Hastings sands. In a district of this kmd, where 

 one series is overlapping another, where there has been much move- 

 ment producing bending of the beds, and where denudation acting 

 unequally exposes the beds cut into under various aspects, much 

 care and circumspection are necessary ; and Mr. Weston, while he 

 gives his own views on the subject, wishes them to be recorded merely 

 as appearing to reconcile apparent difficulties. 



In his paper on the salt-field of Cheshire and the adjoining di- 

 stricts Mr. Ormerod notices numerous movements of the beds and 

 faults. He infers that " dislocations affecting the North Staiford- 

 shire coal-field, the chief Cheshire coal-field, and a considerable part 

 of Cheshire, centre in or near Shutlingstow." 



With regard to the movements to which the coal district in question 

 has been subjected, we must take them in connection with the irregular 

 protrusion of the mountain or carboniferous limestone of Derbyshire, 

 the coal district of the same county, and the continuation of the 

 whole northerly into Yorkshire ; and by so doing we find, — though 

 minor squeezes have depressed or elevated areas of greater or less 

 dimensions, these minor portions taking a variety of forms, — that a 

 great uprise has taken place in a north and south direction for a con- 

 siderable distance, throwing oif coal-fields to the right and left. As 

 we find dislocations in other parts of England, breaking through the 

 mountain limestone and coal-measures, some evidently after their 

 beds had been contorted and bent, anterior to the deposit of the new 

 red sandstone series, since the latter repose quietly without break 

 upon faults, sometimes great, denudation having planed away the 

 broken surface, so that horizontal beds could be continuously de- 

 posited, while other dislocations have affected all the rocks, it be- 

 comes interesting to learn how far the Cheshire and Staffordshire 

 faults may be separated a"S regards geological time. 



It will have been seen from the communication of Professor 

 Ramsay and INIr. Aveline, taken in connection with the memorandum 

 of Professor E. Forbes on the organic remains in part of the district 

 noticed by them, that there would appear to be evidence of coast 

 deposits on the previously disturbed bed of the Llandeilo flag and 



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