Feature
Earth's outer shell suffered a catastrophic break on 6 February last year, when a major fault came to life in southern Turkey. The Anatolian peninsula suddenly lurched to the southwest by as much as 11 metres relative to the Arabian peninsula. Nearly 60,000 people died in one of the most devastating earthquakes of modern times.An earthquake such as this occurs because Earth's crust is divided into shifting tectonic plates. The forces behind plate tectonics play a part in determining nearly everything about Earth, from its climate to the evolution of life.Despite its importance, plate tectonics has remained somewhat of a mystery. Since the early twenty-first century, geologists have been gathering data in search of answers as to when and how plate tectonics began. But these studies have produced a mess of often-contradictory results. "You can have 30 people with 30 different specialisms and we will probably come up with 30 different numbers," says petrologist Michael Brown at the University of Maryland in College Park."It is remarkable, the level of uncertainty over the start time of the process that controls the Earth system today and makes for our habitable planet," says Peter Cawood at Monash University in Melbourne, Australia. The uncertainty is so great that it extends across 85% of the planet's 4.5-billion-year history, he says.However, a consensus is slowly starting to take shape. Sifting through years of data, researchers are finding ways to make sense of the various analyses. Although many uncertainties remain, the history of plate tectonics is finally coming into view.