Geology of the United States A slice of the Earth from the Pacific Ocean through the Pacific Northwest might look something like the adjacent image. Beneath the Cascades, a dense oceanic plate plunges beneath the North American Plate; a process known as subduction. As the oceanic slab sinks deep into the Earth's interior beneath the continental plate, high temperatures and pressures allow water molecules locked in the minerals of solid rock to escape. The water vapor rises into the pliable mantle above the subducting plate, causing some of the mantle to melt. This newly formed magma rises toward the Earth's surface to erupt, forming a
Journey to the Centre of the Earth (album) flee the forest for the Lidenbrook Sea and enter a dark tunnel that plunged deep into rock which they blast through with dynamite. The explosion causes an earthquake, and they become trapped in an active volcano shaft which projects them to the surface of the Earth by Mount Etna in Sicily. The concerts and album were first announced in October 1973, and organised during a break when Yes were touring "Tales from Topographic Oceans". Two sell-out performances were held at 6 and 8 p.m. on Friday 18 January 1974 at the Royal Festival Hall in London, attended by 3,000 people