The world’s oldest meteorite crater is really, really old - 3 billion years old, in fact. And when the 19-mile (30 km) wide meteorite landed on what is now Greenland, it made the biggest crater on earth.
The original crater has been estimated by researchers to have been about 310 miles (500 km) wide, but since the land has eroded since then, it currently measures only about 62 miles (100 km) across. The team led by Danish researcher Adam Garde of the Geological Survey of Denmark and Greenland found crushed rocks in a circular shape and deposits of potassium-feldspar that could only have been liquified by extremely high heat.
Only about 180 impact craters have been discovered on earth, although our planet was likely to have had as many craters as the moon. Most have been destroyed, however, by such processes as plate tectonics, and even wind and rain erosion.
The discovery of this giant crater has sparked a gold rush of sorts. One-third of the impact craters contain significant deposits which include precious metals such as gold, nickel, and other metals, along with valuable minerals, and a Canadian mining company is already exploring the region for mineable deposits.
The previous record for the oldest crater was generally believed to be South Africa’s Vredefort crater. This crater is the largest visible crater in the world, but is believed to be only about 2 billion years old.
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