Ellen, R. and Callaghan, E. 2015. Geodiversity Audit of Spireslack and Mainshill Wood Surface Coal Mines. British Geological Survey Commerical Report CR/15/126. 70pp.
Spireslack Locality 17: Devonian strata
NGR: [276090 630849]
| Key category of interest | Rarity | Quality |
|---|---|---|
| 1. Stratigraphy | 5 | 2 |
| 2. Sedimentary rocks | 3 | 3 |
| 3. Quaternary deposits | 4 | 4 |
Access: The face is difficult to access due to a deep pond — access possible elsewhere over very uneven ground. Current safety: Little evidence for recent rock fall in exposed face, but uneven surfaces and waterlogged conditions underfoot.
Measures to enhance site: Create bridge over pond and even out surfaces to allow easier access. Create viewing platform in front of pond.
Key categories in order of interest (1 = primary interest); Rarity, 5 = only example in Spireslack, 1 = many examples in Spireslack; Quality 5 = exceptional preservation in Spireslack, easy access/viewing potential 1 = average preservation in Spireslack, difficult access/viewing potential
Photograph overview with polygon boundary
Aerial
Site description
Geology
The merit of this site is in its context: a major fault has displaced the Carboniferous strata against Devonian strata at the far eastern margin of the site, providing a natural cut off for mining operations. Following the Devonian era, which was dominated by fluvial and clastic systems, the Carboniferous saw more swamp-like environments developing, causing the formation of vast amounts of coal. The purpose of this locality in the geodiversity audit is to provide a sense of scale for the site and to illustrate the importance of the Carboniferous strategically within
Scotland compared to rocks of other geological periods. The Devonian strata, the Swanshaw Formation at this locality, are composed of massive red-brown medium and coarse-grained terrestrial sandstones with subordinate pebble beds. Peat overlying till is visible above the rock face, although not as accessible in the Quaternary deposits described in locality 16.
Access and enhancement suggestions
Access is impeded by a pond but an appreciation of the massive sandstone can be given without crossing the pond. Levelling of the ground to provide access to the face and providing a crossing over the pond would enable hands on access to the older strata.