The BGS Lexicon of Named Rock Units — Result Details
Bonaly Volcanic Member
| Computer Code: | BNY | Preferred Map Code: | BNY |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Pridoli Epoch (SO) — Lochkovian Age (DO) | ||
| Lithological Description: | Lowest flows are feldspar phyric andesites and upper flows are fine-grained andesites. Feldspar phyric olivine basalts and pyroxene-andesites, trachybasalts, rhyolites and trachytes are also present. | ||
| Definition of Lower Boundary: | Not exposed. Faulted against Ballagan Formation to the north and overlain by Kinnesswood Formation to west. | ||
| Definition of Upper Boundary: | Unconformable: upper flows of andesites and basalts overlain by conglomerates and grits of Greywacke Conglomerate Formation and rhyolite of Bell's Hill Volcanic Member. | ||
| Thickness: | 350m maximum | ||
| Geographical Limits: | Pentland Hills. | ||
| Parent Unit: | Pentland Hills Volcanic Formation (PDH) | ||
| Previous Name(s): | Bonaly Group [Obsolete Name And Code: Use BNY]
(BOG)
Beds C, E [Obsolete Name and Code: Use BNY] (-1372) Bonaly Volcanic Formation [Obsolete Name and Code: Use BNY] (-1373) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Reference Section | Crags forming north slope of White Hill. Feldspar-phyric andesites and fine grained andesites. | ||
| Type Section | Dean Burn, draining north west slopes of Capelaw Hill. Feldspar-phyric olivine basalt and pyroxene andesite, interbedded trachybasalt, and thin rhyolites. | ||
| Reference(s): | |||
| Browne, M A E, Smith, R A, and Aitken, A M. 2002. Stratigraphical 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. 67 pp. | |||
| Peach, B N, Clough, C T, Hinxman, L W, Grant Wilson, J S, Crampton, C B, Maufe, H B and Bailey, E B, 1910. The geology of the Neighbourhood of Edinburgh (2nd edition). Memoir of the Geological Survey of Scotland, Sheet 32 (Scotland). | |||
| Mitchell, G H. 1962. The geology of the neighbourhood of Edinburgh. (Explanation of Sheet 32) Third Edition. (Reprinted 1980). Memoir of the Geological Survey of Great Britain (Scotland). | |||
| Mykura, W, 1960. The Lower Old Red Sandstone igneous rocks of the Pentland Hills. Bulletin of the Geological Survey of Great Britain, No.16, 131-155. | |||
| Cameron, I B and Stephenson, D, 1985. British Regional Geology: The Midland Valley of Scotland (3rd Edition). (London: HMSO for British Geological Survey). | |||
| Geikie, A, 1897. The Ancient Volcanoes of Great Britain. Vol.1, 317-325. (London: Macmillan). | |||
| Howell, H H and Geikie, A, 1861. The Geology of the neighbourhood of Edinburgh (1st edition). Memoir of the Geological Survey, Scotland. | |||
| Mykura, W, 1986. Pentland Hills. 161-173 in Lothian Geology. An Excursion Guide. McAdam, A D and Clarkson, E N K (editors). (Edinburgh: Scottish Academic Press.) | |||
| Thirlwall, M F, 1988. Geochronology of Late Caledenian magmatism in northern Britain. Journal of the Geological Society, Vol.145, 951-967. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| S032 S032 | |||