The assessment of the conservation value of geological sites
in the marine environment was undertaken by the Centre for Applied
Oceanography, University of Wales Bangor on behalf of the Joint
Nature Conservation Committee Contract Number F90-01-655.
This study follows on from the feasibility study carried out by the
University in 2003
('The Conservation of
Nationally Important Marine Geoscience Sites: a feasibility study'
(Furze, 2003).
The generation of a preliminary list of prospective offshore
candidate sites within the pilot study area has proved to be
difficult; this is primarily attributable to both a deficiency with
respect to original data and also the availability of existing
data. During the compilation of the report it has become clear that
a more significant volume of data is available in relation to
coastal sites as opposed to those located further offshore.
Data procurement via the BGS is ongoing and will be submitted
at a later date as an addendum to this report. The initial list of
prospective candidate sites has, as a consequence, been restricted
and comprises 49 possible locations. Of these, 15 are existing
coastal geomorphology Geological Conservation Review (GCR) sites
which have been assessed in order to justify possible extensions
into the marine environment. The majority of the remaining 34 sites
have been identified by sources within the School of Ocean
Sciences, University of Wales, Bangor and from sites listed within
the British Geological Survey's Offshore Regional Reports relating
to the geology of the Irish Sea and Cardigan Bay. It is, however,
considered highly likely that many more additional and smaller
prospective sites exist within the pilot study area but have as yet
either to be identified or the data related to them is restricted
in terms of its distribution or availability.
During the initial phase of the numerical assessment, when
reviewing the status of the existing coastal GCR sites, it became
clear that additional criteria needed to be considered in order to
more accurately assess the possible justification of boundary
extension. When assessing the scientific criteria it became evident
that all existing coastal GCR sites, together with their
prospective extension zones, consistently produced high scores;
however, it was considered that any possible justification for an
extension into the marine environment would also need to account
for a site's 'dependence' upon its immediately adjacent marine
environment. This dependence would primarily relate to contemporary
processes, for example sediment supply and erosion, which would
not/could not necessarily apply to the offshore sites. It was
considered that these active processes probably needed to be
considered and quantified within the threat criteria section for
existing GCR's only, and as a consequence, a 'Correction' factor
has subsequently been introduced. The introduction of a correction
factor related to a coastal sites inter-dependence upon its
adjacent marine environment and its assessed threat value has
introduced a 'corrected threat factor' which often enhances the
initially evaluated threat factor.
During the initial search, review and assessment of the
potential sites, it became clear that most sites have as yet to be
either formally identified, named or even assigned technically
appropriate scientific descriptions. For the purposes of this
report reference numbers have been assigned to the sites
assessed.
The marine thematic block assigned to an individual site has,
in some cases, not been entirely clear. For example, in the case of
the roches moutonnées, rock pinnacles, sea mounds and submarine
canyons; the features primarily fall within the category related to
the Quaternary, as glacial/postglacial processes have resulted in
their formation or appearance. It must, however, be noted that
other thematic blocks relating to solid geology could also be
utilized in these cases.
Tables have been produced for both the offshore sites and
coastal GCR's in an attempt both to illustrate and highlight
potentially more important sites which may warrant conservation or
extension within the marine environment. The tables have been
constructed using scores produced via the scientific criteria
section. In cases where equal values for the aforementioned
criteria have been produced, a secondary driving mechanism related
to the site's potential threat criteria has been implemented. For
the purposes of this report, lower potential threat values are
deemed to accentuate a site's position in relation to the site's
importance and it's potential conservability.
The top scoring offshore site was assigned potential geotope
status, whilst the second placed site was defined as potentially
three separate 1st order sites nested within larger second order
conservation zones. The majority of the other assessed sites were
defined as prospective 1st order Marine Earth-science Conservation
Areas (MECA's).
The table produced in relation to the coastal sites seemed
consistent with the initial assessment conducted within the
feasibility report in that it highlighted many of the sites that
would possibly benefit from an extension into the sub-tidal
environment. These include the sites of Ainsdale, Ynyslas,
Newborough and Morfa Dinlle.
No attempt was made to define an accurate boundary with regard
to any potential site's exact location and lateral extent. This was
largely due to the lack of available data with respect to the
majority of sites subjected to numerical evaluation. For the top
scoring sites warranting potential conservation, a much more
detailed study would be required in order to accurately define and
delineate their exact lateral extension within the marine
environment.