Across
- 1. A person who specializes in writing and serves as a record keeper
- 5. The process by which crust sinks back into the mantle at a colliding plate boundary
- 6. A deep undersea valley where crust sinks towards the mantle
- 7. ocean ridge An undersea chain of mountains that is part of a long system of underwater mountains
- 8. A device that reflects sound waves off underwater objects and records the echoes
- 9. A sharpened reed used to press markings into clay tablets
Down
- 2. A mixture of copper and tin; used to make stronger tools
- 3. A type of writing made up of wedge-shaped markings
- 4. A picture or drawing that represents a word or idea
- 10. floor spreading The process by which molten material adds new crust below Earth’s bodies of water