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