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
The Crust Brothers The Crust Brothers The Crust Brothers, a band formed by Stephen Malkmus and members of Silkworm (Michael Dahlquist, Tim Midgett, and Andy Cohen), released one album, "Marquee Mark", a live recording of their December 5, 1997, show at the Crocodile Cafe in Seattle, Washington. MTV reporter Tayloe Emery wrote an article for MTV Music News and reported that the show was a benefit for the Washington Wilderness Coalition organized by Trevor FitzGibbon to protect roadless areas. "One of the goals of the coalition is to pressure government officials to push forward laws that would serve to protect the wilderness area,