Across
- 1. devices that reflects sound waves off of objects underwater and records the echoes
- 3. when crust sinks down into the mantle at a colliding boundary
- 4. a drawing that is used to represent a word or an idea
- 6. the process when molten adds new crust to the Earth’s bodies of water
- 7. a type of writing made of wedge-shaped marks
- 8. an undersea valley where the crust sinks toward the mantle
Down
- 1. a sharp reed that is used to make marks in clay tablets
- 2. a chain of mountains that is part of a system of underwater mountains
- 5. a mixture of copper and tin, and used to make better tools
- 6. someone who is specialized in writing and is a record keeper