IV.—The Upper Trias of Leicestershire

Extract

Although the Rhætic beds are not exposed continuously along the eastern boundary of the Keuper outcrop, they have been proved at many points from the River Trent in the north on the Nottinghamshire border to Glen Parva in the south. South of this point there is so much drift, and borings within the Liassic outcrop have been so isolated or shallow, that there is a gap in our knowledge of the intervening ground between the last point and the Rugby district. The Countesthorpe boring, carried to a depth of over 600 feet, encountered Upper Keuper beneath the Drift, with no intervening Rhætics. Commencing in the north in the Gotham district the two outliers are capped above the Red Marl and Tea-green Marl with Rhætic beds, and Lower Lias Limestone (Ps. planorbe zone) above. At Ash Spinney at the south end of the southern outlier, and at the east end of Crownend Wood, Black Shales with Avicula contorta crop out; and on the west side septaria are seen. On the north-west side of the northern outlier at Cottager's Hill Protocardium phillipianum has been found in a well-section near the lane. Rhætic shales are seen in the shafts driven for gypsum works about Gotham.