Sentinel-1 Relative Land Motion Map of the UK 2015-2017
About this Map
This relative land motion map was generated by Geomatic Ventures Limited (GVL) using its in-house advanced interferometric SAR (InSAR) analysis of over 2000 Sentinel-1 satellite images acquired from 2015-2017. More detailed information may be found in the FAQ. The resulting data is copyright Geomatic Ventures Limited 2018.
You can browse the UK Relative Land Motion Map by following the link below which will also allow you to zoom, pan and search for a location or postcode. You can also choose the background and use a slider to reveal the satellite image or map underneath.
Some rectangles highlighting examples of land motion have been included. Please click on them to identify:
Coal Mining. At the beginning of the 20th century, UK coal production was the largest in the world and employed more than one million workers. Since then, production declined with a high rate of pit closures in the 1980s and 1990s, ending with the last deep coal mine being closed in 2015. After decades of groundwater pumping in deep mines, water pumps were turned off after abandonment, causing water levels to rise and resulting in large areas of surface rebound (uplift - blue on the map). However, there are still many instances of collapsing mineworkings deep underground that can lead to surface subsidence (red/brown on the map), decades after closure. Examples of such effects are seen extensively over former coal fields and we have highlighted those in:
Leigh, Greater Manchester
Open Cast Mines, South Wales. Although underground coal mines have been abandoned, there are still a number of open-pit coal mines active across the country. In this highlighted section of the survey, they are clearly seen as red/brown (subsiding) patches, which is actually due to the lowering of the surface level during extraction rather than collapse underground. The largest of the subsiding areas is the open cast mine at the Tower Colliery site in Hirwaun. and the cluster of three red areas a few miles to the east is at Ffos-y-fran, Merthyr Tydfil, which is the largest opencast mine of its kind in Britain.
Peatland, Flow Country, Caithness and Sutherland. Scotland's Flow Country is the largest extent of blanket bog in Europe and the largest single terrestrial carbon store in the UK. It was heavily damaged and fragmented when thousands of miles of drains were cut in the 1980s. Drained peat subsides and, as it subsides, it becomes a significant source of greenhouse gases (globally, drained peat contributes almost 6% of total man-made CO2 emissions). In this land motion map, subsiding areas can easily be identified (in red/brown) and thus the extent of the damage can be assessed. This information can provide valuable inputs to international reports on emissions submitted to the UNFCCC, the Kyoto Protocol and the EU. It also provides useful evidence on the success of restoration campaigns, important for reporting on carbon sequestration.
The Sands of Forvie, Aberdeenshire. The Forvie National Nature Reserve is one of the largest and most undisturbed sand dune systems in Britain. In this map, we can see extensive motion (red/brown) in the north of the reserve, probably due to the drifting of dunes and erosion effects.
Civil Engineering - Northern Line Extension, Kennington Park, London. A subsidence bowl (red/brown on the map) of more than 500m across can be seen centred on Kennington Park in London, just east of The Oval. This is likely due to the sinking of a shaft which completed in November 2017 as part of the works extending the Northern Line of the London Underground to Battersea.
Civil Engineering - Proposed HS2 Phase 2 Rail Route. The HS2 is a planned high-speed rail route, due for completion in the 2030s, that includes links from Birmingham to Manchester and Leeds. As can be seen on the map, parts of the route go through some of the most dynamic areas of coal mining subsidence in England. Careful consideration is taken when planning and maintaining road and rail routes through these regions.
Landslides, Mallerstang, Cumbria. At this location, there are a number of tracks of almost a kilometre in length moving down the hillside from east-to-west (blue on the map) that represent slow-moving landslides into the Eden Valley (see FAQ for more details). Monitoring such landslides is important as they could eventually lead to major threats to infrastructure and the environment.
Soil Compression, Troon Golf Courses. Golf courses are major users of water, sometimes providing their own source through wells and boreholes drilled on their property. This activity along with general soil erosion due to the action of water can lead to subsidence across the course.
Landfill, Little Packington, North Warwickshire. This site, along the M42 near the NEC, was a former gravel quarry, closed in 2015 after almost 50 years dealing with Birmingham's waste. Subsidence (red/brown on the map) is a consequence of shifting solid waste and the decomposition of garbage and can be an indication of leachate, which may cause pollution. Land stability is also an important pre-requisite for the reclamation of landfill sites.
Unknown, Willand, Devon. This almost 2km-wide area of significant (up to 2cm/year) uplift (blue on the map) has been detected by this survey, and in several independent satellite acquisitions. It affects a section of the M5 and also a major railway line. Although we have yet to identify the cause, the fact that vegetated and urban classes are rising in unison suggests it lies deep underground...
HS2 route downloaded from: https://data.gov.uk. Contains public sector information licensed under the terms of the Open Government Licence v3.0.
Sentinel-1 Frames Used
GIA – Glacial Isostatic Adjustment
GPS – Global Positioning System
GVL – Geomatic Ventures Limited
InSAR – Interferometric SAR
ISBAS – Intermittent Small Baseline Subset
SAR – Synthetic Aperture Radar
UNFCCC – United Nations Framework Convention on Climate Change