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Features: March 2012

geodetic control disk

Surveying on the National Mall

The 2011 earthquake near Washington, DC, shook the nation’s capital with enough force to crack stones and loosen mortar in the Washington Monument. But not all effects of the earthquake are visible to the naked eye. What if the ground underneath the Monument shifted because of the quake? Experts from the National Geodetic Survey are nearing completion of a leveling survey that will help answer this question. More...