ENGINEERS WHO really do make the earth move now have every shake, rattle and roll watched from space, the ICE heard last week.
Geotechnical engineers showcased an exciting new technique that analyses radar images collected by satellite over the past ten years to detect otherwise imperceptible ground movements across the planet - providing a new tool in the global battle to predict geological disasters.
Nigel Press and Ren Capes from NPA Satellite Mapping told members how the Permanent Scatterer Interferometry (PSInSAR) system was able to measure the ground movements associated with the construction of the Jubilee Line Extension in London.
Engineers who feel that GPS could provide the same service would be mistaken. GPS is less sensitive, more expensive and can not normally go back in time, Press told the Society for Earthquake and Civil Engineering Dynamics organised meeting.
Large tracts of land with thousands of control points can be measured with the PSInSAR system. This ability means that national maps of ground movement are achievable and there is also the potential to monitor movements prior to natural geological disasters including volcanoes and earthquakes.
Lessons learnt from natural ground movement are potentially the most valuable, as those induced by engineering works are already well understood.
But, as natural processes affecting ground movements are expected to be exacerbated by predicted climate change, the attraction of this particular system looks set to increase.