Across
- 2. boundary, where plates slide sideways past each other
- 5. absence of oxygen
- 6. boundary, where two plates are moving away from each other
- 10. a radioactive form of an element
- 12. tectonics, a theory explaining the structure of the earth's crust
- 14. boundary, when two plates come together
- 16. hotter (less dense) material rises while colder (more dense) material sinks
- 18. the branch of science concerned with earthquakes
- 19. a large stable block of the earth's crust forming the nucleus of a continent
Down
- 1. the influence of closely associated species on each other in their evolution
- 3. devoid of life
- 4. the branch of geophysics concerned with the magnetism in rocks that were induced by the earth's magnetic field at the time of their formation
- 5. requiring oxygen
- 7. the time taken for the radioactivity of a specified isotope to fall to half its original value
- 8. wave, an elastic wave in the earth produced by an earthquake
- 9. a meteor that survives its passage through the earth's atmosphere such that part of it strikes the ground
- 11. zone, where two lithospheric plates come together, one riding over the other
- 13. relating to or resulting from living things
- 15. dating, used to arrange geological events in a sequence
- 17. a detailed description or representation on a map of the natural and artificial features of an area