Geological Sites | Leeds
| Bradford | Calderdale
| Kirklees | Wakefield
 STATUS: RIGS
OTHER DESIGNATIONS:
COUNTY: West Yorkshire
DISTRICT: Wakefield
OS GRID REF. 5 localities listed separately
OS 1:50,000 Landranger 105 York and Selby
OS 1:25,000 EXPLORER 290 York and Selby
BGS 1:50,000 Sheet 78 Wakefield
FIRST DESIGNATED by West Yorkshire RIGS Group in 1996
DATE OF MOST RECENT SURVEY October 2007 by West Yorkshire Geology Trust
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.
HISTORICAL ASSOCIATIONS:
The Brotherton Formation was quarried for burning for agricultural lime,
as it is largely magnesia-free, according to the Wakefield memoir,
p167. Three quarries in the Knottingley area were still being worked
for agricultural lime in 1940, though the canal sides sites are not
mentioned, so had presumably stopped working by then. Some of the quarries
in the Knottingley area also produced good building stone, used for
churches in the area.
 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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