Geological Sites | Leeds
| Bradford | Calderdale
| Kirklees | Wakefield
 STATUS:
Local Geological Site
OTHER DESIGNATIONS:
COUNTY: West Yorkshire
DISTRICT: Bradford
OS GRID REF SE 987 367 to 980 364
OS SHEET 1:50,000 Landranger 104 Leeds and Bradford
OS SHEET: 1:25,000 Outdoor Leisure 21 South Pennines
BGS Geological 1:50,000 Sheet 69 Bradford (Solid and Drift Edition)
FIRST DESIGNATED by West Yorkshire LGS Group in 1996
DATE OF MOST RECENT SURVEY West Yorkshire Geology Trust in February 2009
SCIENTIFIC INFORMATION produced by Neil Aitkenhead
DESIGNATION SHEET UPDATED August 2009
SITE DESCRIPTION:
The designated area is a small site covering the two cloughs above Ponden
reservoir. The
steams have cut into a series of Upper Carboniferous mudstones, siltstones
and
sandstones which show many features which indicate the environment in
which the rocks
were deposited. The steep sandstone cliff of Ponden Kirk shows Scotland
Flags and
Midgeley Grit. In the stream beds is an exposure of Keighley Bluestone
amongst
mudstones and siltstones.
HISTORICAL ASSOCIATIONS:
Contains marine bands used for zoning by Bisat and Hudson. The Keighley
Bluestone
was much used for road stone in previous times and quarried extensively
in the Ponden
area. Green and Russell (1878) recorded that there is a band of hard,
blue, closely
grained rock in the Keighley area, used for road metal and known locally
as the ‘Blues’.
EDUCATIONAL VALUE:
Suitable for secondary and higher level students wishing to study Namurian
sedimentation and the identification of fossilised flora and fauna.
Ponden Clough is
unwooded allowing the geomorphological processes of the locality to
be seen. The
varied rock succession in this section represents repeated cycles of
palaeoenvironmental
change from marine flooding, marking a rise in sea level, then gradual
encroachment of
river delta deposits, followed by river abandonment and soil development.
AESTHETIC CHARACTERISTICS:
There are extensive views over moorland and unspoilt countryside. The
area has strong
connections with the Bronte Sisters especially at Top Withins and
Ponden Hall.
ACCESS AND SAFETY:
The site can be reached by a 2km moorland walk via Lower Slack. Alternatively
the
lower sections can be reached along the track via Upper Ponden.
Walking boots and
waterproof clothing are essential. Plenty of parking is available
alongside Ponden
Reservoir (SE 9920 3695). However, the stream beds are rocky
and the slopes above are
very steep.
|
