Pitstone
Quarry SSSI
Grid
reference: SP 934
145
Area
of site: 10.3 ha,
25.4 acres
Access,
location and parking:
Good parking at the College Lake Nature Reserve (pay for permit to park and
enter site). Gates are open from 10 am until 4 to 5.30 pm dependant on time of
year. Groups possible with coach parking possible.
Site
description: Also
known as College Lake and it is a nature reserve and conservation area for public use.
Entrance to the site is located close to Bulbourne. The section notified for
SSSI coverage is the area of the Middle and Upper Pleistocene deposits – the
grid reference given is that of the ‘channel’ location.
Geological
interpretation:
The disused quarry was used to extract Lower to Middle Chalk for the cement
industry. The Lower Chalk is now mostly flooded as the old workings have become
the area of a deep lake and shallow water wetland area for nature. However, the
far slopes do show the Middle Chalk, although gradually becoming less exposed
due to slope degradation and plant colonization.
There
are good examples of Chiltern dipslope deposits all over the site, of Middle to
Upper Pleistocene age. Slope processes, such as solifluction are visible in
several areas. A number of channels occur in the slope deposits, which were
infilled with water-lain deposits. Three channels yielded significant faunal and
floral assemblages and showed they were of different ages. The oldest is claimed
to be a new interglacial period occurring between the Hoxnian and the Ipswichian
interglacials. It lies stratigraphically below the second channel deposit which
contains hippopotamus bones and is thought to represent the Ipswichian
interglacial (the last interglacial). The evaluation of these various
channel-fills and their stratigraphic relationship continues, making this an
important stratigraphic site for the Pleistocene.
Current
and potential educational use
(geology, ecology, archaeology, industrial archaeology):
The site is of excellent value for education, although the channel locality is
not open for viewing. There is a display of fossils and reconstructions on site
and other geology to view.
Conservation
interest:
To maintain the integrity of all the potential geological resources.
Threats
to site (present and future): None envisaged as it forms part of a nature conservation area.
Constraints
(basic risk assessment): usual risks for open public access nature site.
Development
potential:
This site could make an excellent RIGS site. The RIGS coverage is for the
geology of the remaining site, not that already protected under the SSSI
notification.
Reference
list/bibliography:
Recommendations:
Develop the interpretation of the chalk geology and slope deposits for public
enjoyment, other than the ‘channel’ area which is under SSSI protection.