W. H. Hudleston — CreechhaiToic in Purbeck. 149 



II. — Creechbakkow in Purbbok. — No. 2.^ 



By W, H. HuDLESTOX, M.A., F.R.S., F.G.S. 



Additional Points in Stratigraphy. 



IN my paper published in the Proceedings of the Dorset Field Club 

 (vol. xxiii), I dwelt at some length on certain borehole sections 

 made towards the northern base of Creechbarrow with a view to the 

 discovery of Pipeclay. This course was adopted in the hope that 

 a study of these sections might throw some light on the strati- 

 graphical relations between the Creechbarrow Beds on the hilltop 

 and the Pipeclays lower down, if indeed there are any strati- 

 graphical relations beyond a mere jumble of irregular deposits whose 

 precise orientation can never be disentangled. Whether this latter 

 supposition is the true one or not, the exceptional character of the 

 Creechbarrow Beds, as a local feature, remains the same, even 

 although we cannot decide whether they go under, over, or into the 

 Pipeclay series. Before attempting any further speculation as to 

 the possible stratigraphy of the region I will call attention, at any 

 rate, to its topography as shown in the accompanying figure. 



A 

 B 



!^:;^^?sii^»i!wa«^*^»;««?5^«ir^ 



///////// '///////rj/// 



^^— Pipe-clay Series 



nSSO.-.Creechbarrow-beds 



IIIIll...Chail< 



Fig. 1. — Creechbarrow from the north-east, based ou a photograph by the late 

 Mr. Laurence Pike. 



A. Summit of CreechbarroAv, 637 feet. 



B. The eastern spur. 



C. The northern ridge (approximate dip slope). The hilltop limestone extends 



along this ridge as far as the 500 feet contour. 

 D D. The Pm-beck HiU ; maximum elevation 654 feet, just behind Creechbarrow. 



E. Blackhills Plantation, about the 300 feet contour. 



F. Spoil-heaps of the clay workings. 



North-East Side of Creechbarroio : Additional Particulars as to the 

 Creechbarrow Beds. — From the above figure the topographical 

 relations of the Creechbarrow Beds to the Pipeclay series can be 

 seen at a glance ; the former looks down upon the latter. It is 



1 No. 1 appeared in the June number of the Geological Magazine for 1902. 

 It was then intimated that the subject would be treated more fully in the Proceedings 

 of the Dorset Field Club. This has been done, and a portion of the additional matter 

 is now, by the kind permission of the Publication Committee of the Dorset Field 

 Club, reproduced in the Geological Magazine. This portion relates mainly to the 

 lithology and palseoutology of the Creechbarrow Beds. — W. H. H. 



Plate XI, illustrating this paper, will appear in the May number with the remaining 

 part of the article. — Edit. Geol. Mag. 



