Harelaw Lava Member

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Harelaw Lava Member (HWLA), Dunlop-Eaglesham Block, Carboniferous, Midland Valley of Scotland[edit]

The Harelaw Lava Member is part of the Clyde Plateau Volcanic Formation.

Name[edit]

Previously named the Harelaw Lavas. See MacPherson and Phillips (1997)[1]; Phillips and MacPherson (1996)[2]; MacPherson et al. (2000)[3].

Lithology[edit]

The Harelaw Lava Member consists of trachyte, trachyandesite and trachybasalt lava.

Stratotype[edit]

The type area is the Dunlop–Eaglesham moors between Glasgow, Kilmarnock and Hamilton, discontinous across an area around Halker (NS 4100 5000), Neilston (NS 5200 5800), Glenouther Rig (NS 4800 4800) and Blackwood Hill (NS 5500 4700).

Lower and upper boundaries[edit]

The base is unconformable on the Moyne Moor and Neilston lava members that consist of basaltic lavas.

The member is overlain by the Upper Flow Moss Lava Member. The contact is considered unconformable and locally intrusive. The trachytic lava flows are thought to have had significant dome-like topographical expression immediately after eruption.

Thickness[edit]

More than 70 m.

Distribution and regional correlation[edit]

Dunlop–Eaglesham moors between Glasgow, Kilmarnock and Hamilton, discontinous across an area around Halker (NS 4100 5000), Neilston (NS 5200 5800), Glenouther Rig (NS 4800 4800) and Blackwood Hill (NS 5500 4700).

Age[edit]

Mid Visean (Arundian to Asbian).

References[edit]

  1. MacPherson, K A T, and Phillips, E R. 1997. The geology of the Clyde Plateau Volcanic Formation of the Kilmarnock district (Sheet 22E), central Scotland. British Geological Survey Technical Report, WA/97/88
  2. Phillips, E R, and Macpherson, K A T. 1996. Petrology, geochemistry and classification of the Clyde Plateau Volcanic Formation, Kilmarnock district (Sheet 22), Midland Valley, Scotland. British Geological Survey Technical Report, WG/96/24
  3. MacPherson, K A T, Smith, R A, and Akhurst, M C. 2000. Geology of the Kilmarnock district. Sheet description of the British Geological Survey, Sheet 22E (Scotland)