Across
- 4. tide occurs twice a month when the sun and moon are at a right angle to the earth
- 5. and fall both have equal daytime and night time
- 6. eclipse moon’s shadow
- 7. when one object in space blocks another from view; a shadow
- 9. has longer days and shorter nights
- 11. currents transfers heat from one place to another
- 12. floor spreading the process by which molten material adds new oceanic crust to the ocean floor
- 13. boundary where two plates move past each other in opposite directions
- 15. the rise and fall of sea levels
- 17. the process by which oceanic crust sinks beneath a deep ocean trench and back into the mantle at a convergent plate boundary
- 19. tectonics the theory that pieces of earth’s lithosphere are in constant motion driven by convection currents in the mantle
Down
- 1. boundary where two plates move away from each other
- 2. a theory that suggests all the continents were once connected
- 3. has shorter days and longer nights
- 8. boundary where two plates move towards each other
- 9. caused by the tilt of earth’s axis
- 10. ocean ridge an undersea mountain chain where new ocean floor is produced
- 14. tide caused by the alignment of the sun and moon with the earth
- 16. eclipse earth’s shadow
- 18. ocean trench a deep valley along the ocean floor