106 Miss Eyton — Newer Deposits of North Shropshire. \ 



III. — On the Pleistocene Deposits of North Shbopshike. J 



By Miss Charlotte Eiton.^ 



IN Professor Harkness's very interesting paper " On the Middle 

 Pleistocene Deposits," he alludes to the beds described by Mr. 

 George Maw, " in the valley of the Severn, between Bridgenorth and 

 Shrewsbury, which seem to accord with the shell-bearing beds of 

 Ireland." ^ 



The Pleistocene deposits of Shropshire (of which I have attempted 

 a brief description in my little work on the Geology of North 

 Shropshire^) are of much greater extent and importance than the Severn 

 valley beds (which, however, represent a very interesting portion of 

 them). They cover a large part of the North Shropshire plain, both 

 on t\\Q east and west, and are found both north and south of the 

 Wrekin and the adjacent Carboniferous anticlinal. The lowest of 

 these beds is a stiff blue clay, containing rounded, not striated 

 pebbles, with Lias-fossils, which covers the country for some miles . 

 west of Shrewsbury. It lies upon the upper Bunter Sandstone, 

 between the base of the Keuper beds, as seen at Pimhill and Harmer- 

 hill, and on the Severn. A section obtained by a well-sinking at Dunn's 

 Heath, about three miles from Shrewsbury, gave a. thickness of 104 

 feet before water was reached. Similar sinkings in different parts of 

 its extent give about the same thickness, varying only by a few feet, 

 though in one instance, at Leaton, a very short distance from Dunn's 

 Heath, water was found at a much less depth. 



The clay is visible on the surface at Leaton brickfield, the Old 

 Woods, Fennymere, and Petton.* It is difficult to determine its 

 exact boundary, as much of it is concealed by the overlying drifts, 

 but it seems to extend westward up to the base of the small Keuper 

 hills of Nesscliffe and the Clyffe, and then, following the low ground 

 west of Grinshill and Hawkestone, to continue northward in the 

 direction of Ellesmere, before reaching which it is thickly overlaid 

 with drift. A portion of the clay near the Hayes Farm was found 

 to be loaded with crystals of perfectly clear calcareous spar. The 

 only shell which I have been able to obtain from this bed is a small 

 but very perfect specimen of Fusus antiqims, from the Old Woods 

 clay-pit, very different from the shattered remains of the overlying 

 bed. Mr. Gwyn Jeffreys does not consider it a glacial form.^ 



^ It seems right to say that this paper was written before the publication of the 

 article by Mr. Searles "Wood, Jun., otherwise, perhaps, the opinion of Prof. Hark- 

 ness might not have been adopted quite so implicitly, although it coincides with 

 the idea I had previously conceived. The key to the problem in Shropshire lies in 

 the position of the blue clay, and confirmatory evidence may be found in the many 

 still undetermined fragments of shells which abound in the overlying beds. Next 

 summer's work may add Tellina obliqua or Nucula Cohholdia to our fauna. — C. E., 

 Jan., 1870. 



' Geol. Mag., Dec, 1869, p. 546. 



3 Notes on the Geology of North Shropshire, chap. 6. 



* The Geological Surveyors give a thickness of 120 feet to the drift near Petton. 



^ See a section given by Mr. G. Maw, south of Workington, Lancashire, where a 

 lower blue clay is exposed, overlaid by reddish, silty clay. Geol. Mag., Vol. VI. 

 Feb., 1869, p. 72. 



