This page explains the National Landslide Database (NLD) on the BGS GeoIndex under the following headings:
The National Landslide Database holds over 16 500 records of landslides and is the definitive source of landslide information for Great Britain; it excludes Northern Ireland, Isle of Man and the Channel Islands.
Each landslide within the National Landslide Database is identified by a National Landslide Database ID number and a point location, as shown on this map. The National Landslide Database ID number represents an individual survey of a landslide, rather than just the landslide itself. This is because there could be several phases of movement within or extensions to the same landslide, particularly if it is a large and complex one. Subsequent surveys of the same landslide may be recorded in the database with the same National Landslide Database ID number but with a new Survey Number.
|Location||South of Scarborough, North Yorkshire, England|
|Grid checked by BGS||Y|
|First known date||1993|
|Last known date||1993|
|Reference||Holbeck Hall case study|
The point symbols at the designated location do not reflect the size and shape of the corresponding landslide, but just denote the recorded presence of a landslide within a range of accuracy.
How do I get a map of the landslide extent?
Where possible, each point is located at the highest point on the landslide backscarp feature. This is not always possible to locate as, for example, backscarp information is often omitted from older geological maps. In these cases, the highest point on the mapped landslide polygon is used. If this information is not available, the point is located approximately.
How is the point location accuracy expressed?
In the 1990s, BGS inherited approximately 8500 landslide records from the then Department of Environment (DoE). This survey was carried out by Geomorphological Services Limited (GSL) and involved their staff searching through the literature, including BGS maps and reports, to gain as much information about landslides in Great Britain as possible.
These landslides were recorded as either six-figure grid references (1 km accuracy) or eight-figure grid references (100 m accuracy) thereby incorporating a considerably large locational inaccuracy when displayed on a map. The BGS Landslides Team has been working for several years to re-locate these landslides with more accuracy and to remove duplicates or incorrect entries inherited from the DoE database. This process is still underway and will take several more years to complete.
Consequently, the data are displayed in the GeoIndex to show if the landslide record has been validated by the team.
|Y||The Landslides Team have validated this landslide point correctly to within a range of accuracy.|
|N||The Landslides Team is yet to validate this landslide.|
|+||U||The Landslides Team has tried to find information about this landslide but the original reference material is unavailable.|
Each point, which has been validated by the Landslides Team, is given an accuracy range. This is expressed as ±10 metres, ±100 metres or ±1000 metres unless a specific range is known (e.g. GPS).
If the landslide is from BGS geological maps, there will be a mapped extent of the landslide from the time of mapping. This can be obtained by contacting firstname.lastname@example.org or by purchasing the geological map extracts. This is not a geomorphological map.
Most of the data have come from BGS geological maps. The following are the various sources of data included in the database; these are written as bibliographic references in the table in the GeoIndex:
BGS cannot provide the references given in the table free of charge.
Paper geological maps at 1:50 000 and 1:10 000 scale and the accompanying memoirs or sheet explanations are available to purchase through the BGS shop. Digital map data are available to purchase through email@example.com.
BGS memoirs and sheet explanations can be purchased or viewed in the BGS library.
BGS reports may not be available due to confidentiality.
Non-BGS reports — BGS cannot provide these without written consent from the authors.
Council records cannot be obtained through BGS. Please contact the appropriate council.
Media reports cannot be obtained through BGS. They may still be available online or the media can be contacted direct to request the report.
Data is supplied in accordance with the GeoReports Terms & Conditions.
In addition to the terms and conditions above; important notes about the National Landslide Database data:
Copyright in materials derived from the British Geological Survey's work, is owned by the Natural Environment Research Council (NERC) and/or the authority that commissioned the work. You may not copy or adapt the data, or provide it to a third party, without first obtaining NERC's permission. Please visit the IPR web pages or contact the BGS Head of Intellectual Property Rights, British Geological Survey, Environmental Science Centre, Keyworth, Nottingham NG12 5GG. Telephone: 0115 936 3100. Email: firstname.lastname@example.org.
© NERC 2012 All rights reserved.