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GCG Study Tour - Doing More With Less

Collection viewing 1

The Geology Curators Group was set up in 1974 to improve the state and status of geological collections in public institutions and to encourage the highest standards of curatorial care. With a comprehensive upgrade of the storage facilities at Guernsey Museums & Galleries scheduled to be more or less completed as far as the geological collection was concerned, Spring 2013 seemed like a good time to invite the UK-based group to visit.

Long-time GCG member Alan Howell, Guernsey's Senior Curator and resident natural historian, issued the casual invitation last year, not really expecting it to be accepted. The Geology Curators Group committee was keen to come however, so a two day study tour programme was drawn up, emulating similar events in the past. The first day was to include formal presentations, a chance to see the collections and a discussion session around the theme of 'Doing More With Less'. The second day would be a field trip looking at the geology of Guernsey led by experienced Channel Island geologist Dr John Renouf. View photo gallery...

Day 1 - Thursday 25 April 2013

It was apparent the previous day that there was a problem. Only by travelling well in advance had two of the expected seven UK delegates reached the island. Nobody else arrived on Wednesday due to flight disruption by fog and it was obvious that even if the weather cleared enough to allow flights in, we could not expect a full complement of delegates until lunchtime at the earliest. The programme of presentations and the visit to the collections were hastily moved to the afternoon. Something had to go and unfortunately that was the general discussion session.

After lunch the meeting opened with a welcome and overview of the museum service by Guernsey's Director of Museums, Dr Jason Monaghan. He started out by pointing out the differences between Guernsey and the UK in terms of political affiliation and funding for the service. He then covered the scope of the service with its three museum sites and some eighty historic sites around the island. 

Alan Howell then described the history of the geology collections, interwoven with a general history of public museum development in the island. The two parallel lines of development being the Lukis family collections bequeathed to the States of Guernsey in 1907 and the Guille-Allès Museum established as part of a private philanthropic trust in the 1880s. The moves and meagre curatorial history of these collections were described and illustrated, together with recent developments since they were brought together (but not amalgamated) in 1978.

The most recent advance in the care of these collections has been a one million pound capital programme (spread over four years) to upgrade the storage provision at the museum's curatorial and technical base. The background and methodology of this project was described by Clive Martin, Operations Manager for the service. The scheme has benefited greatly from the services of an experienced and sympathetic project manager from the Treasury & Resources department, an excellent main contractor and the forbearance of staff who have all been affected by the ongoing works. By judicious planning it has been possible to upgrade the building area by area without actually moving the collection off-site, saving considerably on removal costs, staff time and risk of damage to items in transit. As far as the geological collection was concerned this has simply meant carrying the specimens downstairs into a new, controlled environment. The environmental controls are the best that could be achieved to meet the appropriate British Standards within the available budget.

After a short refreshment break the party made the ten minute walk to the collections facility in St John Street and were given free access to the main run of mobile shelving housing the bulk of the geological collection. The racking by Brunzeel was custom built to take the grey plastic Alibert Eurotrays which have been used to house most of this collection since the late 1980s. The trays were formerly housed in free-standing dust proof wooden cabinets and the service is currently researching the retro-fitting of doors on the racks to prevent dust ingress.

Day 2 Friday 26 April 2013

Experienced Channel Island geologist Dr John Renouf had been invited and very kindly agreed to lead a field trip for the group to examine the geology of Guernsey. To start the day he gave a short overview presentation at the museum for the benefit of our UK visitors. Then, in company with several local geology enthusiasts the party moved by car to visit the first locality of the day. This was Spur Point towards the north of the island where the St Peter Port Gabbro is exposed and displays spectacular layering due to varying concentrations of hornblende crystals. The gabbro is a very varied rock and this was easily demonstrated by the actual outcrops and the range of pebbles on the beach.

The party then moved anticlockwise around the island to Cobo Bay on the west coast for a short stop to view the distinctive pink Cobo Granite. This is a very even-grained rock which cuts very well and can be seen in many buildings around the island, though it is not currently being quarried. The group then moved south to L'Eree and stopped at both sides of the headland. On the north side the L'Eree Granite was examined with its large banded orthoclase phenocrysts and consideration was also given to the evidence for past sea level changes in the low cliff. Moving to the south side the sea level change evidence was made even more obvious by the 8 metre raised beach exposure near the slipway. Dr Renouf is particularly involved with geological matters relating to local archaeology (especially sea level changes) and spent some time on the headland pointing out areas of archeological interest before leading the group to visit the nearby Creux Es Fees passage grave - one of the historic sites managed by the museum service.

After lunch the group moved along the south coast and drove down to Petit Bot Bay to examine the Icart Gneiss. This rock is more than 2 billion years old and started life as a porphyritic granite. The large feldspar crystals are still apparent but to a varying degree they have been squeezed and 'streaked out' by the ancient earth movements which changed the granite into a gneiss. The Icart Gneiss forms most of the cliffs along Guernsey's south coast.

The final stop of the day took us to Guernsey's south-east extremity at Jerbourg, near the Doyle Monument. From there the group walked down the cliff path network to Divette, pausing above Marble Bay to view the 8 metre wave cut platform visible as a ledge on the foreshore. At Divette ancient metasediments were examined which are even older than the Icart Gneisses within which they occur. A massive quartz vein was also visible - part of a system which cuts right across the Jerbourg headland. Then, taking the cliff path again, the party moved on to the final locality on the east side of St Martins Point. The objective here was a fallen block of calcified loessic head, containing occasional calcareous concretions with cold climate non-marine mollusc sub-fossils. Dr Renouf left the party to explore this themselves (in order to catch his flight home) but no concretions were subsequently found.

Despite the unfortunate loss of the first half day and the relatively small number of participants involved, the meeting was well received by those who took part. The weather caused a loss of time at the beginning and great inconvenience for all concerned but certainly came up trumps on the second day. Almost anyone who visits the coast of Guernsey on a sunny day in spring is sure to enjoy the experience.

  • Collection viewing 2
  • Spur Point 2
  • Spur Point 3
  • Spur Point 4
  • Spur Point 5
  • Spur Point 6
  • Cobo Granite
  • L'Eree 1
  • L'Eree 2
  • Petit Bot 1
  • Petit Bot 2
  • Divette 1
  • Divette 2
  • St Martins 1
  • St Martins 2