Mull Lava Group

Mull Lava Group
Stratigraphic range: Palaeocene epoch, Palaeogene
Type	Group
Sub-units	Mull Central Lava Formation, Mull Plateau Lava Formation, Staff Lava Formation
Overlies	Moine Supergroup and Mesozoic sedimentary rocks
Area	840sq km
Thickness	1800 m (estimated)
Lithology
Primary	basalt lavas
Location
Country	Scotland
Extent	Isle of Mull, Ardnamurchan, Morvern
Type section
Named for	Isle of Mull

The Mull Lava Group is a Palaeogene lithostratigraphic group (a sequence of rock strata) in the west Highlands of Scotland. The name is derived from the Isle of Mull where they are most extensively seen, forming the bedrock across much of the island. They extend into the mainland peninsulas of Ardnamurchan and Morvern and also out to sea.

Lithology and stratigraphy

The Group consists of around 1800 m thickness of lavas erupted from the Mull Central Volcanic Complex and display a range of chemistries. The Group includes (in descending order, i.e. oldest last):

• Mull Central Lava Formation
• Mull Plateau Lava Formation
  • Ben More Pale Member
  • Ben More Main Member
• Staffa Lava Formation
  • Ardtun Conglomerate Member
  • Gribun Mudstone Member (known as the Beinn Iadain Mudstone Formation in Morvern)

These three formations were formerly known as the Staffa, Main and Pale ‘suites’ of the Plateau Group ^[1]

References

1. Emeleus, C.H.; Bell, B.R. (2005). British Regional Geology: the Palaeogene Volcanic Districts of Scotland (Fourth ed.). Nottingham: British Geological Survey. pp. 69–77. ISBN   0852725191.