Structure of the Earth obducted onto the continental crust and preserved as ophiolite sequences. Many rocks now making up Earth's crust formed less than 100 million (1) years ago; however, the oldest known mineral grains are about 4.4 billion (4.4) years old, indicating that Earth has had a solid crust for at least 4.4 billion years. Earth's mantle extends to a depth of 2,890 km, making it the thickest layer of Earth. The mantle is divided into upper and lower mantle. The upper and lower mantle are separated by the transition zone. The lowest part of the mantle next to the core-mantle boundary is
Journey to the Center of the Earth (2008 direct-to-video film) Earth's crust and into the very mantle of the Earth. This is where the operators encounter hidden dangers awaiting them at the Earth's core. The team has to deal with prehistoric creatures in order to both save the research team and to return safely to the surface of the Earth. Journey to the Center of the Earth (2008 direct-to-video film) Journey to the Center of the Earth (released in the UK as Journey to Middle Earth) is a 2008 direct-to-DVD film created by The Asylum and directed by David Jones and Scott Wheeler. The film is a loose adaptation of