Lithosphere of these xenoliths have been investigated by many methods, including analyses of abundances of isotopes of osmium and rhenium. Such studies have confirmed that mantle lithospheres below some cratons have persisted for periods in excess of 3 billion years, despite the mantle flow that accompanies plate tectonics. Lithosphere A lithosphere ( ["lithos"] for "rocky", and ["sphaira"] for "sphere") is the rigid, outermost shell of a terrestrial-type planet, or natural satellite, that is defined by its rigid mechanical properties. On Earth, it is composed of the crust and the portion of the upper mantle that behaves elastically on time scales of
What on Earth! What on Earth! What on Earth! (French: "La Terre est habitée!") is a 1966 National Film Board of Canada animated short co-directed by Les Drew and Kaj Pindal. The film is a mockumentary, introduced in its opening credits as produced by the "National Film Board of Mars" that takes a humorous look at car culture from the point of view of fictional Martians, who mistake automobiles for Earth's true inhabitants and people as their parasites. It attempts to examine the sociology of the automobile as the dominant species on earth, and makes wild guesses about the lifestyle, feeding habits, mating