Across
- 2. what makes a matchhead catch fire
- 5. people who explore caves
- 7. space rock that burns up in earth's atmosphere
- 8. a ____ channels molten rock called lava
- 9. a scientist who studies rocks
Down
- 1. each person on earth uses two tons of this mineral per day
- 3. the deepest ___ ever drilled on earth is 40,230 feet
- 4. a spacerock that makes it to earth's surface
- 6. molten rock
- 7. if you open a ___ it is the same all the way through