Darvel Lava Member
Darvel Lava Member (DLLA), Dunlop-Eaglesham Block, Carboniferous, Midland Valley of Scotland
The Darvel Lava Member is part of the Clyde Plateau Volcanic Formation.
Name
Previously named the Darvel lavas. See MacPherson and Phillips (1997)[1]; Phillips and MacPherson (1996)[2]; MacPherson et al. (2000)[3].
Lithology
The Darvel Lava Member consists of alkali basalts and basanites. Near the unit top, trachybasalt also occurs.
Stratotype
The type area is the Dunlop–Eaglesham moors between Glasgow, Kilmarnock and Hamilton, limited to around Darvel (NS 6000 4000) and Newmilns (NS 5000 3700) just north of the Inchgottrick Fault.
Lower and upper boundaries
The Darvel Lava Member is unconformable on the mainly lithic arenite succession of the Lower Devonian Swanshaw Sandstone Formation (see Browne et al., 2002)[4].
The member is mainly overlain by the Kirkwood Formation of the Strathclyde Group. The contact is considered unconformable with the volcaniclastic sedimentary rocks draping an eroded land surface formed from the member. Locally, the member is interbedded with, or overlain by, the Gowk Stane Volcaniclastic Member.
Thickness
Not known.
Distribution and regional correlation
Dunlop–Eaglesham moors between Glasgow, Kilmarnock and Hamilton, limited in area around Darvel (NS 6000 4000) and Newmilns (NS 5000 3700) just north of the Inchgottrick Fault.
Age
Mid Visean (Arundian to Asbian).
References
- ↑ 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
- ↑ 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
- ↑ 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)
- ↑ Browne, M A E, Smith, R A, and Aitken, A M. 2002. Strati-graphical framework for the Devonian (Old Red Sandstone) rocks of Scotland south of a line from Fort William to Aberdeen. British Geological Survey Research Report, RR/01/04