U3A Geology Group – activities in 2019

Talks 11th January - AGM; followed by David Dickinson: “Coal, Where would we be without it?” The industrial revolution which began in during the 18th Century was made possible by this country’s ample coal deposits. The conversion of carbon into heat allowed us to exploit iron ore deposits, construct steel structures and harness steam power. 8th February – Emeritus Prof Chris King: ”Volcano in the Mendips – would we survive?” With excellent practical demonstrations throughout, Chris illustrated the evidence for 425 yr old volcanoes in the Mendips. He outlined the different categories of volcanic eruption that can occur and said that those that took place in the Mendips were similar to that of Mt St Helens in 1980, i.e. explosive. So too were the Tintagel volcanoes in the Carboniferous. 8th March – Dr Danny Clarke-Lowes: “Libyan Geology – looking for oil”: Libya culturally is divided into two parts by the Gulf of Sirt. The present impasse over ownership of Libya’s oil stems from this divide. The largest oil fields lie in the otherwise deserted Sirt Basin (an extensional oil province similar in many ways and scale to the North Sea but predominantly with Cretaceous reservoirs rather than Jurassic), positioned inland from the Gulf of Sirt. 12th April – Dr Stan Coates: “Geology and mineral resources of Afghanistan.” Stan introduced us to the geology and mineral resources of Afghanistan and explained the difficulties in carrying out fieldwork in this area and of working and living in Kabul. 10th May – Jan Robertson: “Have some Madeira, M’Dear” - an alcohol-free look at the island of Madeira (but with appropriate cake). Jan explained how it came to be, what geology can be seen there and how that geology affects the way people live. 14th June – Richard Edmonds: “Jurassic Coast”. Richard gave an overview of the wonderful geological sequences displayed along this World Heritage Coastline in anticipation to our visit to parts of it in June. 12th July – Jenny Landon: “Yellowstone: A slumbering super-volcano”. In 1872 Yellowstone was designated as the first National Park in the USA on account of its natural wonders. Since then we have learned that this site has been responsible for some of the biggest and most explosive volcanic eruptions on Earth. But will it erupt again with devastating consequences? 9th August - Dr Doug Robinson : "The Making of the Mendips" (in anticipation of our visit in September). Doug gave us an insight into the journey of Somerset over hundreds of millions of years from the southern hemisphere to its present latitude explaining how the various types of rocks to be found in the present-day Mendips were formed along the way. 13th September – No meeting. 11th October – Brendan Shaw: “Fossils”. Using examples from his collection, Brendan focussed on the invertebrate fossils: explaining the different types: moulds, casts and trace fossils etc. and how these came to be formed. He explained how the changing nature of the fossils formed over different era could be used in the relative dating of rocks. 8th November – Dr Peter Grainger: “Formation of (part 4)”: “We continued our exploration of the geology of SW England up the geological column through the Jurassic and Cretaceous from 200 to 66 million years ago. We looked at the effect of the break up of Pangaea and a return to marine conditions on the sedimentary rock types laid down and the life in and around the sea. As the Atlantic opened up and sea levels continued to rise throughout the Cretaceous the distinctive chalk formed and tectonic activity again started to create new structures in the South West.” 13th Dec – Christmas activities: bring-and-share festive food. A ‘science forum’ for members to tell interesting science facts plus a ‘fake news’ quiz.

Group Visits and Hands-on Sessions Friday 25th January - sedimentary rocks - led by Nigel Spencer. Sedimentary rocks cover 2/3 of the Earth’s surface, yet only amounts to 8% of the volume of the Earth’s crust. They are formed by the transformation of pre-existing rocks… Friday 22nd February – metamorphic rocks with lots of examples – led by Nigel Spencer. Friday 22nd March – metals and ores - led by David Dickinson with contributions to the displays by members. Monday 8th April – Walk at Hele Bay then on to . Car share. Saturday, 18th May – Car share visit to School of Mines, Exeter University, Penryn Campus. A day led by Calum Beeson who explained what could be learned using their various high- tech equipment. He also discussed the beautiful museum exhibits and in the afternoon we had a long hands-on teaching session with the petrological microscopes. Thursday 27th June – Coach Trip to Lulworth Cove and Durdle Door with walks led by Andrew Griffiths. He guided the group through the ages as we walked from Stair Hole to Lulworth Cove beach then along to spectacular Durdle Door. Andrew informed us about the stages of deposition and how the strata were then modified during the Variscan Orogeny. Thursday 18th July – Car-share to Sandymouth near Bude for a walk led by Jane Anderson for the National Trust who explained the highly folded layers of mainly Carbonifeous rocks exposed in the beach cliffs. Friday 6th September – Jurassic Coast boat trip from Exmouth with geology commentary by Richard Schrivener. A leisurely sail Eastwards looking closely at this fascinating and geologically very important stretch of coastline (but rather a rough ride back!). Monday 23rd September – A walk in the Mendips led by Dr Doug Robinson, starting at Deer Leap and going on to Ebbor Gorge. The geology included a section from the Lower to Upper Carboniferous. This area saw intense coal exploration in the mid to late 1800s, with remnants of coal shafts and an adit in the area but none were productive. The beds dip south and have good outcrops of fossiliferous limestone and quartzite. A major thrust fault; the Ebbor Thrust, cuts through the rocks with the oldest Carboniferous bed juxtaposed against the youngest. Thursday 24th October – Car share to Bristol to see the Museum and behind-the scenes tour of the Geology section. Friday 25th Oct – The first of this year’s ‘hands-on’ sessions: Members brought along their own samples of rocks, fossils or minerals that they found interesting and wished to show the others or maybe wanted opinions on what they were.

Friday 22nd November – Norman Govier gave an illustrated talk about the history of the mining carried out in and around with displays of the rocks and minerals found in this area.