Wednesday, April 11, 2018

Mapping Britain's Ups & Downs

The Relative Land Motion map showing subsidence on Wanstead Flats in East London

A new interactive map of the United Kingdom plots very small changes in elevation to show where the country is experiencing subsidence and where the land is experiencing uplift. Zoom in on any location on the Relative Land Motion Map of the UK and you can find out whether an area saw any warping of the land surface between 2015 and 2017.

On the interactive map areas colored red have experienced subsidence and areas colored blue have seen uplift. These small movements in land surface have been detected by comparing imagery captured by the Sentinel-1 satellite. Satellite interferometry has been used to detect small changes in different satellite images of the same location. In this way it is possible to show where the land surface has experienced subsidence or uplift over time.

In the UK most changes to the levels of the land surface are caused by "groundwater levels, underground mining, landslides, surface erosion (such as in open-cast mines) and soil compression (such as in drained peatlands)".

On the interactive map some examples of areas that have seen changes to land surface levels have been highlighted on the map. The white rectangles show areas where mining, civil engineering projects or geological features have caused significant subsidence or uplift. ​If you select one of these rectangles on the map a small information window will open explaining why the area has experienced warping of the land surface.

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