Across
- 3. molten rock on Earth's surface
- 5. A dense sphere of solid iron and nickel at the center of Earth
- 7. an era when dinosaurs existed; means "middle animal life"
- 13. the layer of Earth below the crust; upper part is solid and lower part is semi-solid
- 14. a rock that has changed from another rock because of heat, pressure, or a chemical reaction
- 18. the study of fossils
- 21. the hard outer layer of Earth made of crust and hard, upper mantle; broken into tectonOuter core
- 22. rock that forms when melted rock (magma or lava) cools and hardens
- 24. any remains, trace, or imprint of animal or plant life preserved in Earth's crust
- 25. Cycle transformation that changes one type of rock into another
- 26. a subdivision of a geologic period
- 27. a span of time within an era
Down
- 1. an era when trilobites, corals, brachiopods, early fish, and early amphibians existed; means "ancient animal life"
- 2. a crack in Earth's crust where movement can occur
- 4. the fluid portion of the mantle that has special properties
- 6. formed on the exterior of Earth
- 8. a broad span of geological time based on the general type of life existing during that time
- 9. a layer of hot, liquid metals surrounding the innercore
- 10. the period of time ranging from the formation of Earth about 4.6 billion years ago to today
- 11. formed in the interior of Earth
- 12. molten rock under the earth's surface
- 15. an orderly arrangement of atoms and molecules with a specific shape determined by its chemical composition
- 16. a fossil that characterizes a particular period of time
- 17. All the fossils throughout the history of the Earth
- 19. Name for the time in earths early history that accounts for ninety percent of earth's time, but only cellular organisms lived.
- 20. an era when mammals exist; means "recent animal life"
- 23. Rigid outer layer of the Earth.
- 26. the largest division of geologic time