Precambrian gneisses that comprise the Torngat Mountains are among the oldest on Earth and have been dated at roughly 3.6 to 3.9 billion years old.[2] Geologists recognize the gneisses of the Torngats as a part of the Canadian Shield or Laurentian Upland,[3] which, composing the very old North American Craton, split from the continent of Rodinia roughly 750 million years ago to form the geologic core of North America.[4]