Arkley, S. L. B., Browne, M. A. E., Albornoz-Parra, L. J. and Barron, H. F. 2011. East Dumbartonshire Geodiversity Audit. British Geological Survey Open Report, OR/09/19. 265pp.

EDC 16: Finniescroft Wood, Lennoxtown

Grid reference: [NS 62328 76845]

Site type: Natural section

Site ownership: Not known

Current use: Private country

Field surveyor: Sarah Arkley & Luis Albornoz-Parra

Current geological designations: None

Date visited: 13th March 2009

Site map

(Figure 16) Finniescroft Wood Location Map

Summary description

Disused limestone quarry.

The Hurlet Limestone marks the base of the Lower Limestone Formation. Immediately underlying the Hurlet Limestone is the Alum Shale and Hurlet Coal

The Hurlet Seam (including both the limestone and coal) is one of the most important datum lines within the Carboniferous sequence, as it was the lowest workable seam which could be recognised over wide areas of western Scotland. (Hinxman, 1920). The limestone is generally 3 to 4 ft thick north of the Clyde, dark grey in colour and largely composed of encrinital debris, the coal is usually soft, contains pyrite and is of poor quality, a thin layer of 'alum shale' separates the two. (Robertson, 1937).

The alum shale at one time supplied material for a considerable alum industry nearby. The coal was only valuable for burning the lime on the spot. The lime however, was of good quality and extensively worked.

The Hurlet Limestone is visible in small stream exposures, containing crinoid debris.

EDC 16: Stratigraphy and rock types

Age: Lower Carboniferous Formation: Lawmuir Formation

Rock type: Sedimentary Rock Cycles of the Strathclyde Group Type

Age: Lower Carboniferous Formation: Lower Limestone Formation

Rock type: Sedimentary Rock Cycles of the Clackmannan Group Type

Age: Lower Carboniferous Formation: Hurlet Limestone, Lower Limestone Formation

Rock type: Limestone

Assessment of site value

Access and safety

Aspect/Description

Road access and parking Parking is possible for one or two cars at both the SW and NE end of the wood,

Safety of access Within the wood access is over rough uneven ground

Safety of exposure Some steep ground is very wet and slippery. Also when viewing outcrops within the stream care should be taken on slippery rocks

Permission to visit No permission sought

Current condition Small outcrops kept clean by flowing water

Current conflicting activities

None

Restricting conditions None

Nature of exposure Stream exposure

Culture, heritage & economic

Historic, archaeological & literary associations

Adjacent to Campsie Alum Works. Rating: 3.

Aesthetic landscape Wooded area. Rating: 2.

History of earth sciences None known. Rating: 0.

Economic geology Workings in Hurlet Limestone, Alum Shale and coal. Rating: 3.

EDC 16: Geoscientific merit

EDC 16: Finniescroft Wood, Lennoxtown. Geoscientific merit.

Total Geoscientific merit score 31

Current site value

Community Few people would venture into the woods which cover the site of 5 the old quarry, however there is a signed footpath which runs just north of the woods. Rating: 4.

Education Importance of this site is due to the presence of the Hurlet Limestone which was quarried extensively in the area, but the outcrops are not that impressive from an educational point of view, although gain value due to their proximity to the forme Campsie Alum Works, SE of Lennoxtown. Rating: 4.

Fragility and potential use of the site

Fragility Erosion, Natural Overgrowth

Potential use School

Geodiversity value

The main value of this site is the presence of the Hurlet Limestone, this unit was extensively worked across the Central Scotland and surviving exposures are rare. Rating: 3.

Photographs

(Photo 84) Beds of crinoidal limestone outcropping in the stream. Looking SW.

(Photo 85) A more resistant limestone bed forms a small waterfall in the stream. Looking WSW.

(Photo 86) Iron-rich water issuing from the bank- side. Looking SSE.

Bibliography