On Glacial Sections at York, and their Relation to Later Deposits

Abstract

The various deposits of boulder-clay, sands, gravels, brick-earths, warp and peat, near York, have been sufficiently exposed by building operations, brick fields, and gravel pits to show this very simple relation. Resting upon the deep-seated Triassic rocks lies the irregular boulder-clay, which forms all the higher ground, reaching in Severn’s Mount to 100 feet above the river Ouse. Where the stream escapes from between its undulations, the top-most layers have been washed and re-arranged as glacial gravels. Its hollows have been levelled up with the sediment thus produced, forming the brick-earths and warpy clays; whilst peat deposits have completed the work where the depth, elevation, or remoteness of the original hollow prevented the brick-earths from accomplishing that end. An examination of Plate XXIII., Fig. 1, will show the following relations. The glacial beds form the chief feature of the region, not only monopolising all the ground more than about 30 feet above the Ouse level (or 50 to 60 feet above that of the sea), but also forming extensive low-lands, except close by the river. Where these are sandy, and rest on clay, healthy commons still remain, such as Tilmire, Langwith, Strensall, and Riccall. At present, unfortunately, there are no good sections in the glacial beds, but their character can be made out near the New Goods Station, at several points round the Mount, especially on Holgate Hill, and also at the Poppleton junction of the Harrogate and North lines, about two miles out. But, before discussing former exposures, it ...