Lecture: Shetland - Scottish geology in the wrong order!
Speaker:
Entry Fee
Members: Free
Visitors: £5.00
Date and Time
19:30 -
Location
Bath Royal Literary and Scientific Institution, 16-18 Queen Square, Bath BA1 2HN
Lecture Description
The Shetland Isles are something of an enigma. Even weather maps often miss them off and few people realise that they are 80 miles north to south! Chris has been visiting them for nearly 30 years and over that time has come to love Shetland, its geology, landscape and people. Only in recent years has the geological story begun to be told with any degree of accuracy and even now there are lots of problems still to be solved.
The Shetlands are traversed by a number of major north-south strike slip faults that are thought to be a continuation of the Great Glen fault line. As a result there are slivers of Lewisian, Moinian and Dalradian rocks and even repetition on an east-west traverse. (Hence the title of the talk!)
To really hot things up there‘s a classic sequence on Unst and Fetlar that amount to an ophiolite complex. There‘s even material from below the Moho! In a bizarre twist, there‘s serpentine (along with talc) on Unst that tops the UK with the Lizard of Cornwall providing the very similar tail. A recent survey has revealed high levels of rare earth elements and even Platinum on Unst. The sequence is topped off with 1500 metres of an amazing meta-conglomerate.
The overlying Devonian geology is no less spectacular with the sandstones forming the UK‘s highest cliffs on Foula. On the Eshaness peninsula and on the island of Papa Stour, amazing Devonian volcanics can be seen comprising both basalts and rhyolites. No talk on Shetland would be complete without mention of the offshore geology that gives rise to the large oil industry that has been the lifeblood of the islands‘ economy for over 30 years.
By the end of this talk you will all know rather more about our most northerly outpost!