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A fascinating map detailing ground levels in central London has charted Crossrail’s route beneath the city.

Researchers at Imperial College London created the map based on data gathered over the last five years, calculating the average annual change in surface levels throughout the capital.

And cutting straight through the centre of the image is the new Crossrail line – highlighted in red.

The rail line was completed in 2015 after 1000-tonne boring machines excavated 26 miles of tunnels through the heart of the city.

Crossrail Tunnel July 2017 - In pictures 13 show all Crossrail Tunnel July 2017 - In pictures 1/13 Cable management systems installed in Stepney Green eastbound cavern crossrailtunnel0407 2/13 Overhead catenary system installed in Thames Tunnel crossrailtunnel0407 3/13 Engineers installing overhead catenary system in the Connaught Tunnel Crossrail 4/13 Cable management systems installed in Crossrail tunnel crossrailtunnel0407 5/13 Engineers installing overhead catenary system in the Thames Tunnel crossrailtunnel0407 6/13 New gantry installed over tracks at entrance to Victoria Dock Portal crossrailtunnel0407 7/13 Overhead catenary system installed in Thames Tunnel crossrailtunnel0407 8/13 Engineers installing the overhead catenary system in the Thames Tunnel crossrailtunnel0407 9/13 Engineers installing the overhead catenary system in the Connaught Tunnel crossrailtunnel0407 10/13 Overhead catenary system brackets and cable trays installed in entrance to Thames Tunnel crossrailtunnel0407 11/13 Cabling being installed in entrance to Thames Tunnel crossrailtunnel0407 12/13 Installing overhead catenary system in the Connaught Tunnel crossrailtunnel0407 13/13 Installing overhead catenary system in the Connaught Tunnel crossrailtunnel0407 1/13 Cable management systems installed in Stepney Green eastbound cavern crossrailtunnel0407 2/13 Overhead catenary system installed in Thames Tunnel crossrailtunnel0407 3/13 Engineers installing overhead catenary system in the Connaught Tunnel Crossrail 4/13 Cable management systems installed in Crossrail tunnel crossrailtunnel0407 5/13 Engineers installing overhead catenary system in the Thames Tunnel crossrailtunnel0407 6/13 New gantry installed over tracks at entrance to Victoria Dock Portal crossrailtunnel0407 7/13 Overhead catenary system installed in Thames Tunnel crossrailtunnel0407 8/13 Engineers installing the overhead catenary system in the Thames Tunnel crossrailtunnel0407 9/13 Engineers installing the overhead catenary system in the Connaught Tunnel crossrailtunnel0407 10/13 Overhead catenary system brackets and cable trays installed in entrance to Thames Tunnel crossrailtunnel0407 11/13 Cabling being installed in entrance to Thames Tunnel crossrailtunnel0407 12/13 Installing overhead catenary system in the Connaught Tunnel crossrailtunnel0407 13/13 Installing overhead catenary system in the Connaught Tunnel crossrailtunnel0407

Sitting up to 40 metres beneath the earth, the tunnelling project saw the creation of major new stations in central London and the Docklands and upgrades to the existing rail network over a period of three years.

But as the project took place the earth above it likely shifted down a few millimetres a year, researchers have said.

The data used in the map tracks these changes, showing in red where the ground has sunk down and in blue where it has risen up.

Most notable is the strong red line through the centre of the map, which researchers say is the new Crossrail route.

Large patches of red along the route line also mark Crossrail's 10 new stations on the Elizabeth line, set to open in December 2018.

According to the data map, created by Imperial College’s Christine Bischoff as part of her PhD project, the ground level above the line has sunk by 2mm per year on average.

This movement, known as ground settlement, is inevitable during engineering work, the scientists said.

Crossrail engineers carried out extensive work to stabilise the ground during construction, installing “compensation grouting” to minimise movement.

The rail firm said the amount of settlement on the project was lower than anticipated.

Co-supervising the research is Dr Philippa Mason of Imperial College who told the Standard: "That's definitely Crossrail.

“The red blobs [on the Crossrail route line] are where the stations are and you can see where the route splits."

Speaking of the falling ground levels, she said: "It’s fairly normal that there would be some settlement.

"[When] because you build something then the weight of it will cause [the ground] to settle and compress. We always expected to see some settlement."

Also visible is a large red patch to the east of Canary Wharf, an area of London undergoing major development and construction.

The dewatering of the deep Chalk aquifer for building projects - necessary to stabilise ground - could be the cause of this drop in the ground level.

"Drawing the water out makes the ground go down," Dr Mason said. "So it will go back up [after the work is finished]."

Meanwhile a large blue area in the south may have risen due to natural causes, Dr Mason said.

She explained the change in level could be due to ground swell after a large amount of rainfall.

Dr Mason added: "The bigger things you see are usually natural or due to water levels, while the smaller are often mad made... connected with building work."

The data was obtained from 150 remote sensing images captured by TerraSAR-X and other InSAR (Interferometric Synthetic Aperture Radar) sources.

It was processed using at TRE ALTAMIRA in Milan, Italy, using a technique called Permanent Scatterer Interferometry.

Read more on Crossrail and the key property hotspots along the Elizabeth Line: