The BGS Lexicon of Named Rock Units — Result Details
Carnethy Volcanic Member
| Computer Code: | CAHI | Preferred Map Code: | CAHI |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Pridoli Epoch (SO) — Lochkovian Age (DO) | ||
| Lithological Description: | Feldspar-phyric and fine-grained microporphyritic basalts and andesites. Flows have amygdaloidal tops and bases. | ||
| Definition of Lower Boundary: | Conformable: where pale lilac or pink trachytes and andesites of the Woodhouselee Volcanic Member are overlain by feldspar-phyric and fine-grained microporphyritic basalts and andesites. | ||
| Definition of Upper Boundary: | Not seen: faulted against Carboniferous strata to the east. | ||
| Thickness: | Approximately 200m seen | ||
| Geographical Limits: | Pentland Hills. | ||
| Parent Unit: | Pentland Hills Volcanic Formation (PDH) | ||
| Previous Name(s): | Carnethy and Hillend Volcanic Formation [Obsolete Name and Code: Use CAHI]
(-2044)
Carnethy and Hillend Group [Obsolete Name and Code: Use CAHI] (-2043) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Type Area | Carnethy Hill and Hillend, South Edinburgh, Midlothian. | ||
| Type Section | Extensive exposures of porphyritic olivine-basalt and pyroxene andesite on east slope of Caerketton Hill and Hillend Hill. | ||
| Reference Section | Exposures of the distinctive 'Carnethy porphry' (Mykura, 1960, p.142) in several disused quarries on the south east slopes of Carnethy Hill. Olivine-basalt with sub-parallel phenocrysts of tabular labradorite up to 26mm long. | ||
| Reference(s): | |||
| 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). | |||
| 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. | |||
| MacGregor, A G. 1935. Guide to Geological Excursion in and around Edinburgh. Geological Survey Centenary. H.M.S.O. Field Trip Guides. | |||
| Flett, J S. 1914. The geology of the district around Edinburgh. Edited by Monckton, H W. Proceedings of the Geologists' Association, Vol. 25, Part 1, 1-18 and p. 40 (Bibliography). (London: Stanford.) | |||
| Cameron, I B, and Stephenson, D. 1985. British Regional Geology: The Midland Valley of Scotland (3rd Edition). (London: HMSO for British Geological Survey.) | |||
| 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. | |||
| 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). | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| S032 S032 | |||