Fintry Hills Lava Member

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Fintry Hills Lava Member (FHLA), Fintry-Touch Block, Carboniferous, Midland Valley of Scotland

Fintry Hills Lava Member is part of the Clyde Plateau Volcanic Formation.

Name

Previously named the Fintry Hills Group (see Francis et al., 1970)[1].

Lithology

The Fintry Hills Lava Member consists predominantly of plagioclase-macrophyric basalt lavas (‘Markle’ type) with a fairly high proportion of microporphyritic basalts and rare basaltic-trachyandesite (mugearite). Tuff occurs locally at (NS 6409 8794).

Stratotype

The type area is in the highest parts of the Fintry Hills, north-east of Glasgow (NS 6369 8867 to NS 6321 8911) (Francis et al., 1970)[1].

Lower and upper boundaries

The basal basalt of the member lies apparently conformably or disconformably on trachybasalt of the Shelloch Burn Lava Member. The upper boundary is eroded but not exposed.

Thickness

More than 122 m. The top of the member is eroded.

Distribution and regional correlation

The member is restricted to the Fintry–Touch Block (Francis et al., 1970)[1] and specifically to the Fintry Hills, north-east of Glasgow. These rocks crop out across the hilltops of the central part of the Fintry Hills (NS 6369 8867 to NS 6321 8911).

Age

Mid Visean (Arundian to Asbian).

References

  1. Jump up to: 1.0 1.1 1.2 Francis, E H, Forsyth, I H, Read, W A, and Armstrong, M. 1970. The geology of the Stirling district. Memoir of the Geological Survey of Great Britain, Sheet 39 (Scotland)