Surveying wide areas for such tiny changes is nearly impossible. But with advanced radar, geologists can now measure ground motions from space. Geophysics, v. 49, pages 1084-1096 . LME 320 Runnels, Curtis N. Environmental Degradation in Ancient Greece. Almost from the start of its construction 800 years ago, engineers have tinkered with this bell tower to keep it upright despite an unevenly sinking foundation.
Current efforts aim to stabilize the lean.
Chad L. Seeing Underwater with Background Noise. The crash of waves, the patter of rain, the thrum of ship's engines and other activities fill the oceans with ambient sound, much as the sun fills our sky with light. The Global Positioning System. LME 320 Two dozen satellites hovering thousands of miles up can locate your position on the earth's surface to within a few centimeters. Hollister, Charles D. Nadis, Steven Burial of Radioactive Waste under the Seabed.