Abundance of the chemical elements in the Sun and outer planets is similar to that in the universe. Due to solar heating, the elements of Earth and the inner rocky planets of the Solar System have undergone an additional depletion of volatile hydrogen, helium, neon, nitrogen, and carbon (which volatilizes as methane). The crust, mantle, and core of the Earth show evidence of chemical segregation plus some sequestration by density. Lighter silicates of aluminum are found in the crust, with more magnesium silicate in the mantle, while metallic iron and nickel compose the core. The abundance of elements in specialized environments, such as atmospheres, or
Journey to the Centre of the Earth (album) Six Wives of Henry VIII" in October 1972, and had accumulated some money and had written some music for it. The project developed in December 1972 when Wakeman took part in the orchestral concerts of The Who's rock opera "Tommy" at the Rainbow Theatre in London, which featured the London Symphony Orchestra, the English Chamber Choir, conductor David Measham, and musical arranger Wil Malone. Wakeman told his idea for "Journey to the Centre of the Earth" to the show's producer Lou Reizner, who put him in contact with Measham to further discuss plans. Wakeman then produced a demo tape that