Across
- 3. rocks that form when parent rocks get squeezed and heated, but do not melt
- 5. material from once-living organisms
- 6. a scientific theory that uses the fossil record and geologic time scale to explain how living things have changed over time
- 7. rocks that form as magma or lava cools
- 8. the numerical age, in years, of a rock or an object
- 10. a process that takes place on Earth’s surface, where rocks are exposed to the environment and get broken down by wind, rain, freezing/melting
- 13. the development of desert-like conditions due to human activities and natural processes - no longer useful for food production
- 17. a special way of determining the age of rocks (non-living things); scientists measure the amount of radioactive material that is trapped in minerals to determine how much time has passed since the mineral formed
- 22. a well tested explanation for why or how things happen the way they do
- 24. the plate boundary between two plates that move toward each other; collide
- 25. plastic-like layer within the mantle; it is very hot and flexible
- 26. a process that moves large amounts of rock up to Earth's surface and to higher elevations; this is associated with mountain building
- 28. molten rock that is inside the Earth
- 29. the action that occurs at a convergent boundary where the denser plate sinks below the less dense plate
- 30. the scientific law that states that in undisturbed rock layers, the oldest rocks are at the bottom
- 31. the development of land for houses and other buildings near a city
Down
- 1. the age of rocks or geologic features compared to other rocks and features nearby
- 2. the mountain ranges at the bottom, middle of the oceans; these are much longer than any mountain range on land
- 4. molten rock that erupts onto the Earth’s surface
- 7. the one variable that is changed on purpose in an experiment
- 9. the plate boundary between two plates where the plates slide past each other
- 11. this includes the crust and the uppermost part of the mantle
- 12. - the time it takes for half of the original material to decay or change composition
- 14. rocks that form from weathering and erosion and then compacted and cemented together
- 15. the removal of large areas of forests for human purposes
- 16. the thick, middle layer in the solid part of the Earth; convection currents happen here
- 18. a fossil that represents a species that existed on earth for a short length of time, were abundant, and inhabited many locations
- 19. the measured results of the experiment
- 20. the brittle, rocky outer layer of the Earth
- 21. the plate boundary between two plates that move away from each other
- 23. the contamination of the environment with substances that are harmful to life
- 27. data and observations that are collected through scientific processes (observations, investigations and experimentation)