﻿554 MR. T. F. SIBLY OX THE CARBONIFEROUS [Aug. 1905, 



(iii) Isolated exposures in the Seminula-Zoue. 



(1) A good exposure of beds assigned to the base of this zone occurs, high 



up on the right-hand side of the narrow valley which furrows the 

 side of Milton Hill, in an east-southeasterly direction, below Rans- 

 combe House. 



(2) A horizon near the base of S L is well exposed in two adjoining quarries, 



lying a little north of Milton Road, between Manor Road and Ash- 

 combe Park Road, at the eastern end of the town. The beds displayed 

 are extremely fossiliferous, and have yielded an abundant and inter- 

 esting brachiopod- and coral-fauna. 



(3) Several small exposures in the village of Worle and its immediate 



neighbourhood furnish evidence of the eastward extension of the 

 Seminula-Zone. 



(b) The Area North of the Fault. 



The beds represented on the north side of the fault all belong to 

 the Seminula-Zone. 



In the western half of the area, between the fault, on the coast, 

 and St. Kew's Steps, the exposures are few and not very good. The 

 beds, which are all included in S 1? have a general strike of about 

 E. 17° "N. The coast-section extends rather more than 1000 yards 

 eastward from the fault ; but, since the coast-line runs practically 

 parallel to the strike, the thickness of beds exposed is small. In 

 this section, the upper beds are fossiliferous limestones; the lower 

 beds are comparatively-unfossiliferous ironstained limestones. The 

 former can be seen in several small exposures along the Kewstoke 

 Koad, running through Weston Woods, and in a small roadside 

 quarry, about 500 yards west of the Kewstoke Tollgate. In the 

 escarpment above the Tollgate, the upper part of S 1 is exposed. 



In the eastern half of the area, the exposures are somewhat 

 better. The highest beds represented [SJ are exposed in three 

 quarries lying close together under the eastern end of Worle Hill. 

 The effect of the fault is clearly displayed at this level by an over- 

 fold of the beds, which can be interpreted by an examination of the 

 quarries. The accompanying section (tig. 2) illustrates this fold. 



Fig. 2. — Section across the eastern end of Worle Hill, showing the 



overfold in the Seniinula-S^s. 



S. P N. 



G= SYRINGOTHYBIS-ZOSE. S=SE2JINULA-ZOXE . f= Fault. 



[Length of section = 770 feet.] 



The portion of the section marked C indicates the general dip of the beds 

 south of the fault. 



In the northernmost quarry, the beds dip 20° southwards, the 

 general strike being E. 7° N. These beds have been folded over 



