The BGS Lexicon of Named Rock Units — Result Details

Portree Hyaloclastite Formation

Computer Code: POHY Preferred Map Code: PoHy
Status Code: Full
Age range: Paleocene Epoch (GP) — Paleocene Epoch (GP)
Lithological Description: Predominantly tuffs, with fragments of glassy and devitirified olivine basalt and also accretionary lapilli. The tuffs are interspersed with thin amygdaloidal basalt flows and pillowed basalts. Interflow sediments are sporadically present as typically plant-bearing volcaniclastic sandstones and siltstones.
Definition of Lower Boundary: This is the earliest of the Paleocene volcanic formations and is typically unconformable on the underlying Jurassic strata. Plant-bearing beds are also common at this juncture.
Definition of Upper Boundary: Overlain by the Beinn Edra Formation in northeastern Skye and by the slightly younger Ramasaig Formation farther west.
Thickness: c.30m
Geographical Limits: Northern Skye.
Parent Unit: Skye Lava Group (SKYL)
Previous Name(s): Palagonitic Tuffs and Plant Beds [Obsolete Name and Code: Use POHY] (-2981)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Reference Section  Craig Ulatota, north of Portree, Skye. Emeleus and Bell, 2004. 
Reference(s):
Anderson, F W, and Dunham, K C. 1966. The geology of northern Skye. Memoirs of the Geological Survey of Great Britain, Scotland. Sheet 80 and parts of sheets 81, 90 and 91. Edinburgh, HMSO. 
Bell, B R, and Williamson, I T. 2002. Tertiary igneous activity. 371-407 in The Geology of Scotland, 4th Edition. Trewin N H (editor). (London: The Geological Society.) 
Emeleus, C H and Bell, B R. 2005. British Regional Geology: the Palaeogene volcanic districts of Scotland (Fourth Edition). (Nottingham: British Geological Survey.) x + 214pp. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S080 S080 S081 S090 S091 S081