Trust's first geological reserve
Many people will now be aware from the media that the Trust
has its first geological reserve. This is Harvey's Pit at St
- not any old Tom, Dick or Harvey but the Harveys of Hayle,
the great builders of Cornish engines. The pit was the source
of their moulding sand, and so has very great significance for
the industrial archaeology of Cornwall. Not much is visible
now - a rusting piece of rail, tips of waste sand, and the main
working face, but all so overgrown with over 60 years of oak,
hazel, brambles, nettles, moss - hardly a geological site at
so why are we excited?
Well, firstly, it's the first, and the negotiations by the
solicitors have been protracted. The site was originally offered
to the Royal Geological Society of Cornwall who generously
turned it over to the Trust as a body with experience of
managing reserves. We hope that this experience will soon
include managing several geological reserves.
Secondly, the pit is not any old sandpit but is an SSSI in the
Erth Beds, thought to be the only material of its age in
though there is material of the same age preserved in North
West France (as well as beneath the Atlantic). The age is late
Pliocene, a mere two million years ago or slightly less, and a
marine clay in the nearby Vicarage Pit, owned by the Church
Commissioners, has yielded abundant fossils many of which
indicate a Mediterranean climate and a shallow water depth
(maybe less than lOm). Since the St Erth Beds are found at a
height of 37-50m, this suggests a sea level at the time of
probably about 45m higher than today. Much of the scientific
work was done in the early 1970s (and Professor Frank Mitchell
who led it has deposited his field papers, and much else, in the
St Erth archive at the Trust) but there are many questions still
unanswered - and new scientific techniques to be used.
The undisturbed sand, at the edges of the pit, is the material
which will need to be studied and of course this is a finite
resource: clean off a face and within a year it will be smeared
with soil and being colonised by plants, and need cutting back
again. For this reason all cleaning of the faces needs to be
science-led, and we hope researchers will want to decipher
more of the story from the St Erth Beds.
In the meantime the Trust has as its first geological reserve a
site of international importance, with the potential for adding
more information to the history of the climate and sea levels
of the last few million years, an area of major research
and, of course, of public concern for whatever light it may
throw on potential future changes.
At our AGM on 13th November, Dr Roger Jones will be
talking about making Postcards from the Past and the work of
the BBC Natural History Unit. If you cannot make it at
3.OOpm at Camborne School of Mines, he is also talking at
Bodmin Community College at 7.OOpm. Both talks are
Geological Heritage - please collect one from Allet or ask for
one to be sent to you.
Look out for Cornwall's Geology and Scenery - an
Introduction by Professor Cohn Bristow. This new book
explaining local geology for the layman is ava ilable from book
shops in the county at £13.99 paperback or £17.99 hardback.
The next meeting of the Otter Group will be held at Five
Acres on Saturday 12th October from 1045am until 500pm.
The morning session will deal with otter survey methods and
during the afternoon there will be an opportunity to visit local
rivers to look for signs of otters. If time allows, there will
slides on Californian sea otters. Anyone interested in otters,
and particularly in recording, is very welcome. Please bring
your own lunch - tea and coffee will be provided.
Reptile and Amphibian Group (CRAG)
Amphibians and reptiles continue to hit the headlines Bhs
Frogwatch, newt pond restoration at Hayle, a rare neotenous
newt - one which grows to adult size but remains a tadpole - at
Pencalenick School and terrapins at Swanpool have all helped
to raise the Trust's profile. We've recently set up a partner
group - DRAG - with the Devon Trust, but we're still
desperately short of volunteers willing to do the survey work
so essential to conserving our own native herptiles.
Trust Education Officer Mark Nicholson shows Swanpool visitor Tristan Peck, aged four, what a 50p-sized baby terrapin from a pet shop (left hand) will eventually become. Photo Sion Brackenbury.
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