Geology of Greenland

Greenland is the largest island on Earth. Only one-fifth of its surface area is exposed bedrock, with the rest covered by ice. The exposed area is about 410,000 km².

The geology of Greenland is mainly made up of crystalline rocks from the Precambrian Shield. In the Nuuk area, these rocks are among the oldest bedrock in Greenland, shaped billions of years ago. The bedrock around Nuuk includes two major types: dark Amitsoq gneiss and younger Nuuk gneiss, forming a western gneiss complex that is about 3,600 million years old.

The Isua Greenstone Belt in southwest Greenland contains some of the oldest bedrock on the planet, around 3,800 million years old. This area is important for understanding how Earth's surface looked billions of years ago and holds a large magnetite resource.

Greenland has large deposits of rare-earth oxides at Kvanefjeld. The first gold mine, Nalunaq, opened in 2004 near Nanortalik. It is located in the Ketilidian Orogenic Belt and contains gold-quartz mineralization dated to between 1.77 and 1.80 billion years ago.

The Skaergaard intrusion in eastern Greenland is a layered mafic intrusion formed 55 million years ago during the opening of the North Atlantic Ocean. It is one of the best examples of such formations in the world. Recent studies suggest a hot mantle plume rises from the core–mantle boundary to the mantle transition zone beneath central Greenland.

Fossils

Scientists have found many old remains, called fossils, in Greenland, especially along the east coast. These fossils are from different times, ranging from very old to more recent times. Two important fossils from a time called the Devonian are Acanthostega and Ichthyostega. In a place called Jameson Land from even later times, scientists discovered early examples of mammals during trips led by Farish Jenkins. In another area called the Fleming Fjord Formation, they found tracks made by ancient creatures, along with other interesting fossils like temnospondyls, phytosaurs, and early turtles.