20 Rev. W. D. Conybeare on the Phenomena of Geology 



well as in England, horizontal: throughout Germany and 

 France such is their general situation, excepting in the vici- 

 nity of the great, though local disturbances which have ele- 

 vated the Alpine and Pyrenean chains. 



Partial disturbances are however yet observable. In the 

 lias of Bristol, instances of faults of about 200 feet sometimes 

 extending for more than a mile, and attended with contorted 

 strata, &c. have been noticed in my paper on the South-west coal 

 fields, in the-Geological Transactions. The view of East cliff' in 

 the same memoir presents some smaller faults ; in my present 

 neighbourhood, on the Glamorganshire coast, the lias which 

 reposing on new red sandstone crowns the summit of Pen- 

 narth Point, is towards the centre of that headland depressed 

 about 100 feet to the sea level by a complicated fault. On the 

 north of Barry Island is a fault which must be nearly 200 

 feet, throwing down the lias, and producing at the fracture 

 curved and vertical strata. This fault strikes the contiguous 

 shores of the mainland, and extends over an interval of a mile. 

 Many other faults occur in the lias of this coast, which yet 

 strikingly exhibits the decreasing energy of the convulsive 

 forces in this as compared with the preceding period; for the 

 carboniferous limestone is often exhibited towards the base of 

 the cliffs, (its strata elevated 70 degrees,) on which the red 

 marl and lias repose horizontally; disturbances in the lias of 

 the Yorkshire coast are mentioned in the surveys of Young 

 and Phillips : and the analogous formations of Scotland, in 

 the Brora coal-field, &c. are much deranged : indeed, from 

 their relation to the adjacent primitive mountains it appears 

 probable that the elevation of the latter was in part, at least, 

 effected during this period. 



The oolitic formations have been less examined in this re- 

 spect. I may however mention, that in the neighbourhood of 

 Bath I have found in the hills above Bitton, the inferior oolite 

 to participate in a fault affecting the lias, and throwing the 

 beds down about 200 feet. In the cliffs west of Bridport har- 

 bour on the Dorsetshire coast, a considerable fault accom- 

 panied with vertical strata may be observed. The distur- 

 bances affecting the oolites of the Weymouth district and Isle 

 of Purbeck, must however be referred to the great convulsion 

 which has affected the whole of that part of our coast and the 

 Isle of Wight, subsequently to the deposition of the chalk 

 formation, and during the tertiary period. The analogous 

 formations of the Jura chain are much disturbed, the whole 

 chain exhibiting in places an arched section ; but these con- 

 vulsions must be referred to the forces which have elevated 

 the Alps, and which certainly continued their action until 



the 



