Fintry Hills Lava Member

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

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

Name[edit]

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

Lithology[edit]

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[edit]

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[edit]

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[edit]

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

Distribution and regional correlation[edit]

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[edit]

Mid Visean (Arundian to Asbian).

References[edit]

  1. 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)