 The ‘Vibroseis’ exploration technique (performed with vibrators) was developed by the Continental Oil Company (Conoco) during the 1950s and was a trademark until the company's patent lapsed.Today, seismic vibrators are used to perform about half of all seismic surveys on land.The largest seismic vibration truck in the world, known as 'Nomad 90’, weighs 41.5T and has a 90,000 lbf force.