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You are here > Home > Out & About > Classic
Sites:
Mull - Staffa
(Other classic sites nearby on Mull include Ardtun
Leaf Beds, Loch Ba Ring
Dyke and MacCulloch's
Tree)
'Fingal's Cave' on the Isle of Staffa is internationally famous, having
been the inspiration for musicians, artists, poets and writers for many
years, most notably for Mendelssohn's 'Hebridean Overture'. The island
and cave was brought to the attention of the scientific world by Sir Joseph
Banks (1743 - 1820) who was on route to Iceland on a natural history trip.
In his writings he compares the island's appearances to lava, and it should
be noted that this came before Hutton's
'Theory of the Earth'. The island is composed of columnar basalt and overlying
'slaggy' basalt, erupted as lava flows from the Palaeogene
Mull volcanic centre.
Columnar jointing - as viewed from above on
the Isle of Staffa. © Scottish Natural Heritage.
The Isle of Staffa - a popular tourist attraction
for visitors to Scotland's Inner Hebrides. © Scottish Natural Heritage.
The lava flows on the island were erupted early in the history of the Mull
volcanic centre. The columnar jointing, commonly found in these flows is typical
of the early lava flows only. The presence of ash layers and thin soil horizons
indicate explosive activity and intervening quiet periods respectively. The
composition of these lava flows also differs from the later flows by being
the most silica-rich flows - thought to have formed due to shallower accumulations
of the magma before eruption. These flows are known as the Staffa Magma Type
member and are also seen at Carsaig, Ardtum, Ulva and near Tobermory.
Note: The Mull volcanic centre forms part of the North Atlantic Palaeogene
Igneous Province, along with the other centres of Skye, Arran, Ardnamurchan,
Rum and St. Kilda.
Further reading:
Emeleus, C.H. & Gyopari, M.C. 1992. British Tertiary Volcanic
Province, Geological Conservation Review, Series No. 4. Joint Nature
Conservation Committee, Peterborough, 259 pp.
Emeleus, C.H & Bell, B.R. 2005. British regional geology: the
Palaeogene volcanic districts of Scotland (Fourth edition). (British
Geological Survey, Nottingham.
Stephenson, D. 2005. Mull and Iona - A Landscape Fashioned by Geology.
Produced by: Scottish Natural Heritage & British Geological Survey.
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