OR/14/063 Evaluating East Lothian’s geodiversity

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Whitbread, K, Ellen, R, Callaghan, E, Gordon, J E, and Arkley, S. 2014. East Lothian geodiversity audit. British Geological Survey Internal Report, OR/14/063.

Audit site selection: data sources and criteria[edit]

Potential geodiversity sites were identified by review of available documents and datasets, and through consultation with members of Lothian & Borders Geoconservation. Information sources consulted included:

  • SSSI and GCR documentation (SNH)
  • BGS 1:10 000 geological standards maps and fieldslips
  • BGS BritPits database of Mines and Quarries
  • The Haddington Geological Memoir (McAdam and Tulloch, 1985[1])
  • Lothian Geology: An excursion guide (A D McAdam and E N K Clarkson, 1986[2])
  • Existing scientific literature

From this assessment, 31 potential geodiversity sites were identified for field assessment (Table 3, Figure 5) based on their geoscientific merit according to criteria for valuing the educational, scientific, historical and aesthetic value of sites developed by GeoConservation UK (RIGS).

The selection of sites was made to ensure a comprehensive geological and geographical spread within the East Lothian area, with a focus on the highest quality and most significant geological features of the region.

Geodiversity auditing[edit]

Field auditing was carried out between March and December 2014 by BGS staff (Rachael Ellen, Elieen Callaghan, Sarah Arkley, Katie Whitbread, Hugh Barron and David Millward), with assistance from Mike Browne (Lothian and Borders Geoconservation). The Quaternary sites were audited on behalf of the BGS by John Gordon (Scottish Geodiversity Forum). The criteria used to evaluate the sites are discussed below. As far as possible landowners were contacted prior to visiting or accessing sites, but it was not possible to establish ownership for every site visited.

Data were collated digitally in ARC GIS and reviewed with information from aerial photography, Ordnance Survey topographic maps and BGS digital geological datasets. Site boundaries (discussed below) and key audit data have been supplied to ELC in conjunction with this report.

Of the 31 potential local geodiversity sites identified for field assessment, full audits were conducted at 30. The remaining site, several disused sandstone quarries near Gullane was not audited as the quarries are now fully overgrown and no rock exposures were found.

Defining site boundaries[edit]

The site areas have been delineated through the generation of Shapefiles in ESRI ArcGIS. The method used for delineating site boundaries was developed in discussion with East Lothian Council officers.

The site boundary defines the total area considered to be integral to the geodiversity site and is consistent with a suggested protection zone that is considered to necessary to maintain the integrity of the geodiversity site.

The site boundary may comprise one or a number of areas of exposed geological features including rock outcrops, landforms and any adjacent geologically significant areas considered integral to the site due to landscape and access considerations. In coastal areas, the site boundaries extend offshore to the Mean Low Water Springs defined on Ordnance Survey 1:10 000 scale topographic maps.

The site boundaries are displayed in the maps in the attached site valuations and have been provided as a separate ArcGIS Shapefile. The Shapefile should be regarded as providing the definitive site boundary for reference purposes.

Figure 5    Location map of East Lothian Geodiversity Sites.
Table 3    List of geodiversity sites in East Lothian and sites visited but not included as geodiversity sites
No Site Easting Northing Main feature(s)
ELC_1 Gala Law Quarry 353607 663348 Lower Palaeozoic rocks, fossils
ELC_2 Burn Hope 370105 669951 Lower Devonian sedimentary rocks, fluvial geomorphology
ELC_3 Gin Head (Tantallon) 359439 685331 Lower Carboniferous palaeontology
ELC_4 Dunbar Shore 368100 679300 Carboniferous intrusive igneous and sedimentary rocks (Ballagan Formation), coastal geomorphology
ELC_5 North Berwick Shore 356026 685471 Carboniferous volcanic rocks (Garleton Hills Volcanic Formation), coastal geomorphology
ELC_6 Yellow Craigs Shore 350749 686061 Carboniferous volcanic rocks (Garleton Hills Volcanic Formation)
ELC_7 Old Markle Quarry 358385 677010 Carboniferous volcanic rocks (Garleton Hills Volcanic Formation)
ELC_8 Blaikie Heugh, Balfour Monument 357631 673049 Carboniferous volcanic rocks (Garleton Hills Volcanic Formation), landscape
ELC_9 Kippielaw 358373 675519 Carboniferous volcanic rocks (Garleton Hills Volcanic Formation)
ELC_10 Dirleton Castle 351616 682954 Carboniferous volcanic rocks (Garleton Hills Volcanic Formation), historical association
ELC_11 Craigs Quarry 350852 683556 Carboniferous volcanic rocks (Garleton Hills Volcanic Formation)
ELC_12 Peppercraig Quarry 350800 674500 Carboniferous volcanic rocks (Garleton Hills Volcanic Formation), historical association
ELC_13 Gullane Shore 346590 683094 Carboniferous sedimentary rocks (Gullane Formation), coastal geomorphology
ELC_14 Kilspindie Shore and Aberlady Point 344707 680205 Carboniferous sedimentary rocks (Aberlady and Lower Limestone formations), coastal geomorphology
ELC_15 Prestonpans Shore 338063 674308 Upper Carboniferous sedimentary rocks (Limestone Coal and Upper Limestone formations)
ELC_16 Cockenzie to Port Seton Shore 340377 675935 Upper Carboniferous sedimentary rocks (Upper Limestone, Passage and Lower Coal Measures formations)
ELC_17 Esk Valley 334206 669403 Middle Coal Measures Formation
ELC_18 Pencraig Quarry 357286 676536 Intrusive igneous rocks
ELC_19 North Berwick Law 355847 684235 Geomorphology and Carboniferous plugs
ELC_20 Kidlaw Quarry 350689 664322 Intrusive igneous rocks
ELC_21 Cheese Bay 349242 685684 Carboniferous palaeontology
ELC_22 Garleton Hills 351017 676294 Glacial landforms
ELC_23 Kidlaw Errattic 350976 664604 Glacial deposit and landforms
ELC_24 Lochhouses 361415 682176 Coastal deposits
ELC_25 Seacliff, Scoughall Shore 361506 684062 Coastal landforms
ELC_26 Thorntonloch 376110 673220 Coastal landforms (sandstone)
ELC_27 Whitekirk 358181 681015 Glacial landforms
ELC_28 Tyne Estuary & Belhaven Bay 364408 679790 Coastal landforms
ELC_29 Gullane Bents 347961 683605 Coastal dune system
ELC_30       Aberlady_Bay 346004 681262 Coastal landforms
- Gullane Sandstone Quarries No exposures, partially infilled and overgrown

Geology and geoscientific merit[edit]

The geodiversity site is considered to be represented by the area within the Site Boundary. The assessment of the site condition and valuation of the geodiversity applies to all components of the site that lie within the Site Boundary area.

Site Type[edit]

Geodiversity sites are classified according to the type of exposure or feature and the current use of the site (Table 4, Table 5).

Stratigraphy and Rock Types[edit]

The chronostratigraphic age (e.g. ‘Carboniferous’), lithostratigraphic group and formation (Table 1), as well as the main lithogy for each site are recorded for reference purposes. More details of the main lithologies, their relation to any sub-lithologies that may be present, and the nature of geological structures or other features of interest are given in the geological description.

Table 4    Site Type classification scheme
Site type Description
Natural Section Natural outcrop of one or more geological features forming a linear exposure (river section, cliff face, shoreline etc)
Natural Exposure Natural outcrop of geological feature
Natural Landform Constructional or erosion geomorphological feature (valley, crevasse, dune, all Quaternary features etc)
Natural View Collection of geological features forming a landscape overview interpretation
Mine Workings Feature produced by minerals/coal workings (adit, spoil, hush etc)
Quarry Workings Feature produced by stone/aggregate workings (quarry, pit, waste dumps etc)
Artificial Section Section exposure created artificially by work to construct a road/track/path etc
Excavation Artificially created exposure (excavation — not related to any of the above)
Table 5    Current Use classification scheme
Current Use Description
In Use Feature still used for primary purpose (working quarry etc) as defined by the FEATURE criteria
Disused Feature no longer used for primary purpose and has no other current use
Urban Feature is on publicly accessible lands (but not recreational lands) within the urban limits (allotments, road verges etc)
Open Country Feature is on natural countryside with no unique use (mountains, national park land etc)
Agricultural land Feature is used/forms part of land used for agricultural purposes (farm fields and grazing areas etc)
Recreation Feature is on land specifically designed or modified for recreational uses (parks, picnic areas, etc)
Industrial Feature is on land used for industrial purposes (including waste land forming part of/owned by an industrial complex)
Domestic Feature falls within the limits of private lands associated with dwellings (gardens, stately home grounds etc)

Geoscientific Merit Criteria[edit]

The geodiversity sites have been evaluated according to their geoscientific importance which has been assessed in terms of the relative rarity and quality of key geological or geomorphological attributes that can be seen at the site. The key attributes assessed are:

  • Lithostratigraphy — features indicative of an important stratigraphic horizon and helping to define the sequence of geological strata
  • Sedimentology — features related to depositional processes and settings
  • Igneous/Mineral/Metamorphic — intrusive or extrusive igneous rocks, metamorphic rocks and minerals, and mineral vein deposits
  • Structural geology — faults, folds, shear zones or other deformation features
  • Palaeontology — fossils or trace fossils
  • Geomorphology — landforms and features representative of, or demonstrating, key depositional and erosional processes occurring at the earth’s surface

A single site may have more than one attribute, but is unlikely to have all of them. The rarity and quality of the site attributes have been scaled using the classification schemes defined in Table 6.

Where published materials, such as articles or books, provide details of aspects of the sites geology, the literature sources are also noted. Unpublished materials such as leaflets may be available for some sites, and may be mentioned elsewhere in the site report.

An overall geoscientific merit value statement represents the overall geoscientific value of the site using the rarity and quality scales in Table 6. The overall value summarises the scaling for the relevant attributes, but also includes consideration of the relative importance of the site in terms of its geological uniqueness or conversely, the degree to which it is representative of a larger terrain or unit. For instance a site may be of high value because it is extremely rare, but also because it is an excellent example of rocks that are characteristic of a particular geological terrain or time period.

Table 6    Geoscientific Merit criteria (NB: Midland Valley refers to the region between the Southern Uplands in the south and the Highland Boundary Fault in the north)

Rarity

International Few examples world-wide
National Few UK examples
Regional Few Midland Valley examples
Local Few examples in East Lothian

Quality

Excellent Exceptional preservation and exposure of features
Good Well preserved and exposed features
Moderately Good Moderately well preserved and exposed features
Poor Poorly preserved and exposed features

Cultural, heritage and economic importance[edit]

Known associations between the geodiversity of a site and people (whether locally or nationally) are discussed in terms of aesthetic, historical and economic associations. Cultural associations may include literary, aesthetic, musical or social connections, or sites that have significance for the development of the study of the earth sciences. Historical associations may reflect past military, religious or cultural connections, particularly those associated with strategic landform sites. The extraction of building stone and natural resources including coal and lime are considered in terms of economic associations, these may be active or historic.

The potential uses of the site for research, higher/further education, school education or community development were considered along with potential development activities or information materials that could enhance the use of the site by the local community, education groups and other visitors.

Site condition, access and safety[edit]

Access and Safety[edit]

The nature of access routes to enter or view sites is an important consideration. The ease of road access and parking, near to the site, along with considerations of the safety of access paths and the safety and condition of the exposure are described in the site report.

Current conflicting activities and restricting conditions, such as tides, shooting restrictions and other activities for which the sites may be used are noted in the report. These are known activities only, and it should be noted that there may be further restrictions to site access that are not known to the authors. Visitors to the sites are responsible for preparing their own risk assessments where necessary. The Scottish Outdoor Access Code provides further information on land access in Scotland.

Fragility[edit]

The condition of each site and the stability of rock or sediment exposures were assessed visually during the field survey. Full ground stability assessments were beyond the scope of the survey. Factors affecting the condition of rock exposures at the sites include weathering/erosion, natural overgrowth of vegetation, the effects of sample/fossil collecting, fly tipping and the dumping of waste and construction or other development activities.

References[edit]

  1. MCADAM, A D, and TULLOCH, W. 1985. Geology of the Haddington district. Memoir of the Geological Survey, 1:50 000 Sheet 33W (Scotland).
  2. MCADAM, A D, and CLARKSON, E N K. 1986. Lothian geology: An excursion guide. (Edinburgh: Edinburgh Geological Society, Scottish Academic Press).