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Blue areas show uplift; dots show quakes

In August 2007, Manchester was shaken by a swarm of earth tremors. The first quake (August 10) centred on Clayton recorded 2.5 on the Richter Scale and was felt across Reddish, Didsbury, Failsworth and Denton. The most recent tremor was felt at 05:46 on August 30.

But it's now been revealed for the first time that parts of Manchester have risen by approximately 7cm in just 11 years. So the ground is moving. And it鈥檚 shaking too. But are they linked?

Following the August earthquakes, a leading satellite mapping company NPA Group decided to match historical ground motion information derived from satellite radar data with earthquake epicentres.

What they found was a striking correlation between ground uplift and seismicity (earthquake activity) across the city shown on the map above.

The blue areas on the map are where the ground has risen 鈥� these correspond to Salford up to Prestwich; New Moston and Harpurhey; Audenshaw; and from Clayton to the city centre. The latter area closely matches Manchester鈥檚 recent earthquake zone. [The star is the epicentre of the August 30 quake]

Linked

So what is the underlying cause? Adam Thomas is NPA鈥檚 project consultant:

Seismograph of Clayton quake (Aug 10)

"The mechanisms linking the observed ground motion and earthquake activity are not fully understood but the correlation between the two is compelling. We are investigating this with the The British Geological Survey (BGS) and hope to make a further announcement soon. Meanwhile, this unique source of information is something that individuals and professionals need to consider very seriously."

Dr Roger Musson, a seismologist with the BGS said they鈥檙e confident the earthquakes are not the cause of the uplift. But it鈥檚 possible that the reverse is true:

"We know what鈥檚 causing the earthquakes. The British Isles is being compressed from the North West as the Atlantic plate gets wider and pushes Europe against Africa. You can think of it as a jigsaw that is sat on the table and you start to squeeze it from two opposite directions. Most of the disruption will occur at the sides but it will probably break up at a weak point in the middle too.鈥�

As to what is causing the ground to lift up, I have absolutely no idea. But it鈥檚 possible that the ground uplift is a contributory factor to the earthquakes."