264 DR. C. A. MATLEY ON THE [June I912, 



As a result of the field-work described above, I have been forced 

 to the conclusion that the Arden Sandstone Group, though varying 

 in thickness and lithological composition from place to place, forms 

 a persistent zone extending over all the area described. 



Although the stratigraphy would lead one to expect an outcrop 

 of the Arden Sandstone east of the Upper Marls of Fen End, 

 Wroxall, and Shrewlej^, I have been unable to find it. There is 

 abundant glacial drift about here, and it is possible that an old 

 scarp-slope of the Sandstone Group may be buried beneath these 

 superficial deposits. On the other hand, some miles to the north, 

 at Maxstoke Priory, there is a strong fault, having a north-and- 

 south direction, throwing down Keuper rocks on the west against 

 * Permian ' rocks on the east; and it is not unlikely that its course 

 is continued into the Keuper Marl country on the south, so as to cut 

 out the Arden Sandstone by throwing the Upper Marls on the west 

 against the Lower Marls on the east. 



Y. The Upper and Lower Keuper Marls axd the 

 Eh^tic Beds. 



The Upper Marls, though only some 100 to 160 feet in 

 thickness, occupy a considerable area of the ground described in 

 this paper. They consist mainly of red and chocolate-coloured 

 marls, usually with green mottlings ; but there are also occasionally 

 bands of Avell-laminated, chocolate, micaceous, marly shale and thin 

 beds of green shale and marl. In the rare instances in which 

 there is an opportunity of following the bedding of the marls for 

 some distance, as along the cuttings of the Birmingham & Stratford- 

 on-Avon Railway in 1907, before they were grassed over, green 

 bands only an inch or two thick can be seen to persist as far as 

 the section extends. These Upper Marls also contain a hard band 

 which forms a well-marked escarpment, or builds isolated hills 

 in many places, for example, at Yarningale Common and near 

 Claverdon, Preston Bagot, Bushwood, Tan worth-in- Arden, Wootton 

 Wawen, and elsewhere. There is an exposure close to Morton 

 Bagot Church of a hard, well-bedded, chocolate-coloured marl-rock, 

 which is probably the bed in question. The base of these Upper 

 Marls is seen in places, as at Henley-in-Arden railway-station, to 

 consist of alternating bands of red and grey marl. The top of the 

 Marls is rarely exposed, but the green marls (Tea-Green Marls) 

 immediately underlying the lihaetic are occasionally visible along 

 the margins of the lihaetic outliers. 



Of the Lower Marls the upper portion only is exposed in this 

 district. They consist of red, grey, green, and mottled marls 

 similar in character to those occurring above the Arden Sandstone ; 

 but, on the whole, they seem to be somewhat softer than the Upper 

 Marls. Gypsum occurs in them in the scarp-slope below the 

 sandstone near Henley-in-Arden, as is shown in the cuUing of the 

 railway to Lapworth; and again in the corresponding slope at 

 Spernall Park, where the mineral has been worked commercially. 



