Across
- 4. The solid material found in the centre of some planets at extremely high temperature and pressure, distinct from the liquid outer core
- 8. the upper layer of the earth's mantle, below the lithosphere, in which there is relatively low resistance to plastic flow and convection is thought to occur
- 10. credited as the first to develop a theory of plate tectonics
- 12. a current in a fluid that results from convection
Down
- 1. a layer inside a planetary body bounded below by a core and above by a crust. Mantles are made of rock or ices
- 2. the rigid outer part of the earth, consisting of the crust and upper mantle
- 3. the outermost shell of a terrestrial planet. Earth's crust is generally divided into older, thicker continental crust and younger, denser oceanic crust
- 5. core a fluid layer about 2,400 km thick and composed of mostly iron and nickel that lies above Earth's solid inner core and below its mantle
- 6. new crustal material is formed at oceanic ridges and spreads outward at a rate of several centimetres per year
- 7. suggested that new ocean crust was formed along mid-oceanic ridges
- 9. irregularly shaped slab of solid rock, generally composed of both continental and oceanic lithosphere
- 11. a pattern of magnetic anomalies running in parallel stripes and virtually symmetrically on either side of the ridge