Nena was an ancient minor supercontinent. Nena consisted of the cratons of Arctica, Baltica, and Antarctica. A supercontinent is a mass of land comprising more than one continental core, or craton. ... A craton is an old and stable part of the continental crust that has survived the merging and splitting of continents and supercontinents for at least 500 million years. ... Arctica was an ancient continent approximately 2. ... Baltica is the craton beneath northwestern Eurasia. ...

Chronology

• ~1.8 billion years ago, the supercontinent Columbia was formed. All of the pieces of Nena were together.
• ~1.5 billion years, the supercontinent Columbia disintegrated, leaving Nena as one of the continents.
• ~1.1 billion, Nena became part of the supercontinent Rodinia.
• ~750 million years ago, Rodinia broke apart into two minor supercontinents, Protolaurasia and Protogondwana, as well as the continent Congo. Most of Nena was in Protolaurasia, but Eastern Antarctica was in Protogondwana.
• ~600 million years ago, all land was in one major supercontinent, Pannotia.
• ~540 million years ago, Pannotia rifted apart. All of the cratons of Nena separated. Arctica rifted into Siberia and Laurentia nearly rifted apart. Thus ended Nena.