Lithosphere 50–140 km thick (but beneath the mid-ocean ridges is no thicker than the crust), while continental lithosphere has a range in thickness from about 40 km to perhaps 280 km; the upper ~30 to ~50 km of typical continental lithosphere is crust. The mantle part of the lithosphere consists largely of peridotite. The crust is distinguished from the upper mantle by the change in chemical composition that takes place at the Moho discontinuity. Oceanic lithosphere consists mainly of mafic crust and ultramafic mantle (peridotite) and is denser than continental lithosphere, for which the mantle is associated with crust made of
Costing the Earth Costing the Earth Costing the Earth is a programme on BBC Radio 4 about the environment. According to the programme´s website, it looks at man's effect on the environment and how the environment reacts, questioning accepted truths, challenging those in charge and reporting on progress towards improving the world. The programme reports on all matters relating to the environment. The most recent series has covered topics as diverse as the impact of having a baby on the environment and Germany's energy revolution. Notably the series worked with BBC2's Newsnight programme and the BBC World Channel's Our World to produce a