Hutton's Section, Salisbury Crags

HOGG comes to Edinburgh on 11 and 12 July 2019

James Hutton by Sir Henry Raeburn, on display in the Scottish National Portrait Gallery

The History of Geology Group of the Geological Society of London and the Edinburgh Geological Society are organising an open meeting, Aspects of the History of Geology in Scotland and the North of England, at Surgeons’ Hall, Nicolson Street, Edinburgh.  This meeting will include presentations on Thursday 11 July, followed by a field day on Friday 12 July. Friday will feature a walking tour of sites linked with the history of geology around the city, such as Hutton’s Section on Salisbury Crags. Further details can be viewed at https://historyofgeologygroup.co.uk/scotland meeting.

 

EGS Strategy – Members’ Views

EGS Council is reviewing our five-year Strategy and would welcome views from the membership. The current strategy for 2015-19 is available online at www.edinburghgeolsoc.org/home/about-edinburgh-geological-society/.

Please complete a short online survey (it has only 4 questions) that asks for your feedback on what we do and your ideas for the future. There is a modest prize draw! You can find the survey at www.edinburghgeolsoc.org/survey/.

Deadline for responses – 31 March 2019.

Excursion Programme 2019

Location map for Excursion Programme 2019

Our bumper Excursion Programme for 2019  allows you to experience the superb range of geology that southern Scotland has to offer.   The programme starts on Wednesday 24 April with a short evening excursion around Corstorphine Hill, and runs right the way through to 20-22 September with the weekend excursion to Stonehaven and Highland Boundary Fault. In between these trips, there will be 16 others Wednesday evening (7-9pm), Saturday (all day) and Introductory excursions for new members (x3). Do try and take this opportunity to learn some field geology from our expert leaders.

Field Excursion to Ardross in Fife by Neil Mackenzie

Visit our website page Excursions to find out more details and how to book them.

 

Clough Medal

Clough Medal Lecture – Sideways views of Scottish Garnets: Insights into Metamorphic Processes

The Clough Medal is presented annually to a geologist whose original work has materially increased the knowledge of the geology of Scotland and/or the North of England, alternatively someone who is Scottish and has significantly advanced the knowledge of any aspect of geology. Find out more about Charles T Clough.

This year’s recipient is Dr Tim Dempster from the University of Glasgow School of Geographical & Earth Sciences in recognition of the exceptional contributions he has made to advancing the understanding of the geology of Scotland, particularly the metamorphic geology of the Highlands, where he has employed a wide range of technologies to better understand the processes; and his work as a dedicated and popular teacher of undergraduate students, using the Highlands of Scotland as a ‘natural laboratory’.

In this joint lecture with the Geological Society of Glasgow Dr Dempster talked about garnets, the workhorse of metamorphic petrologists.

Being capable of recording original compositions during growth, garnets allow determination of pressure-temperature paths and durations of metamorphic events.

Concentrating on the contact zone between the garnet and its surrounding minerals, a 3D image of the garnet rather than a thin section – which would offer too small an area for clear analysis – was created. Then the team projected a ‘map’ of the adjacent minerals on the garnet’s surface and variations in its chemistry, e.g. the Calcium content, were recorded.

This way of analysing the garnet showed that the crystal’s growth itself can change the chemistry of the surrounding matrix and hence the reaction path during growth, leading to a ‘false’ temperature recording. Dr Dempster’s studies of garnets from the Scottish Highlands therefore question some key concepts of metamorphic equilibrium.

Background reading: Dempster, T. J., La Piazza, J., Taylor, A. G., Beaudoin, N. and Chung, P. (2017) Chemical and textural equilibration of garnet during amphibolitefacies metamorphism: The influence of coupled dissolution-reprecipitation. Journal of Metamorphic Geology, 35, 1111-1130.