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Geological Sites | Leeds | Bradford | Calderdale | Kirklees | Wakefield
SITE DESCRIPTION Limestones, mudstones and sands of the Permian Brotherton Formation (Upper Magnesian Limestone) are seen in a series of exposures adjacent to the Aire and Calder Navigation Canal. Locality 1: Knottingley Old Hall, SE 499 241 A 5m high exposure of limestone is revealed in the grounds of Knottingley Old Hall. The limestone is finely bedded and gently undulating with vertical joints. The notice in the park comments on the opening of the quarry in 1830. Only one section of these rock faces is designated as a RIGS. Locality 2: SE 498 239 Exposures of honey coloured dolomitic limestone are seen in a 5m high rock face to the east of Gagge Bridge. The limestone shows parallel bedding varying from 5 to 50cm in thickness. This is largely overgrown and only 10m of the face is exposed. Locality 3: SE 497 240 Small exposures of limestone are revealed in the north bank of the canal above Gagge Bridge. The limestone is dolomitic with conchoidal fracture showing no reaction to hydrochloric acid. The bedding varies in thickness from 5 to 50cm. At the west end of this band, the dip of the limestone is locally 15o-20o. Locality 4: SE 499 239 Further exposures of Magnesian Limestone are revealed along the west side of Jackson Bridge, though this site is largely overgrown now. The limestone is very finely bedded with laminations. Locality 5: SE 501 238 Two exposures of limestone are to be found at right angles immediately to the east of Jackson Bridge. This excellent 7m high exposure exhibits true and apparent dip, faulting, laminated bedding and deposits of weathered sandstone. The faces are difficult to approach because of the growth of brambles and nettles, but the face can still be seen from a distance. The section under the road bridge is accessible and shows many interesting features.
EDUCATIONAL VALUE: Localities 1 and 5 are situated further away from the canal bank and have safe flat access to Permian Limestone exposures. The canal side sites are not recommended for educational use. ACCESS AND SAFETY: There is good access to canal side sites via the newly
landscaped areas north of the canal. Sites 2, 3, and 4 are immediately
adjacent to the canal and are potentially dangerous. Locality 5 at Jackson
Bridge is more suitable for supervised parties being situated further
away from the canal. To avoid canal side sites altogether, use Locality
1 at Knottingley Old Hall where there is safe access to the Permian Limestone.
All the sites are accessible by wheelchairs along the canal paths.
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